LNGC DISHA Issue and Update Control .................................................................................. 2 Cargo Machinery Symbols and Colour Scheme .............................................. 3 Part 1 Design Concept of Vessel 1.1 Principal Particulars...........................................................................1 - 1 1.1.1 Principal Particulars of the Ship ............................................. 1 - 1 1.1.2 Principal Particulars of Cargo Machinery............................... 1 - 3 1.1.3 Maker List............................................................................... 1 - 4 1.1.4 General Arrangement .............................................................. 1 - 6 1.1.5 Tanks and Capacity Plan ......................................................... 1 - 7 1.2 Rules and Regulations .......................................................................1 - 8 1.3 Design Concept of the Cargo System ..............................................1 - 12 1.3.1 Cargo Containment System Principle ................................... 1 - 12 1.3.2 Membrane Cargo Containment............................................. 1 - 14 1.3.3 Deterioration or Failure ........................................................ 1 - 19 1.4 Hazardous Areas and Gas Dangerous Zone.....................................1 - 21 Part 2 Properties of LNG 2.1 Physical Properties, Composition and Characteristics of LNG .........2 - 1 2.2 Characteristics of LNG ......................................................................2 - 4 2.2.1 Flammability of Methane, Oxygen and Nitrogen Mixtures ....2 - 4 2.2.2 Supplementary Characteristics................................................2 - 5 2.2.3 Properties of Nitrogen and Inert Gas ......................................2 - 6 2.2.4 Avoidance of Cold Shock to Metal .........................................2 - 8 2.3 Health Hazards ..................................................................................2 - 9 Part 3 Integrated Automation System (IAS) 3.1 General ..............................................................................................3 - 4 3.2 IAS Overview ....................................................................................3 - 5 3.3 IAS Function Operation.....................................................................3 - 7 3.4 IAS Mimics........................................................................................3 - 9 Part 4 Cargo and Ballast System 4.1 Cargo Containment System ............................................................... 4 - 2 4.2 Cargo Piping System ......................................................................... 4 - 3 4.2.1 Liquid Line ............................................................................. 4 - 3 4.2.2 Vapour Line............................................................................. 4 - 3 4.2.3 Spray Line............................................................................... 4 - 4 4.2.4 Gas Line (One Tank Operation).............................................. 4 - 4 4.2.5 Fuel Gas Line.......................................................................... 4 - 4 4.2.6 Vent Line................................................................................. 4 - 4 4.2.7 Inerting/Aeration Line ............................................................ 4 - 4 4.3 Cargo Pumps.................................................................................... 4 - 10 4.3.1 Main Cargo Pumps ............................................................... 4 - 12 4.3.2 Stripping/Spray Pumps ......................................................... 4 - 14 4.3.3 Emergency Cargo Pump ....................................................... 4 - 16 4.4 Cargo Compressors.......................................................................... 4 - 18 4.4.1 HD Compressors................................................................... 4 - 18 4.4.2 LD Compressors ................................................................... 4 - 22 4.5 H/D & L/D Gas Heater .................................................................... 4 - 26 4.6 LNG Vaporizer................................................................................. 4 - 28 4.7 Forcing Vaporizer ............................................................................ 4 - 30 4.8 Vacuum Pumps ................................................................................ 4 - 32
Cargo Operating Manual 4.9 Custody Transfer System .................................................................4 - 35 4.9.1 Custody Transfer System ......................................................4 - 35 4.9.2 CTS Operation ......................................................................4 - 37 4.9.3 HSH Float Level Gauge ........................................................4 - 44 4.9.4 Trim-List Indicator................................................................4 - 46 4.10 Nitrogen Production System ..........................................................4 - 48 4.11 Inert Gas and Dry Air Generator ....................................................4 - 50 4.12 Fixed Gas Detection System ..........................................................4 - 52 4.13 Cargo & Ballast Valve Control System..........................................4 - 58 4.13.1 Cargo Valve Control System ...............................................4 - 58 4.13.2 Ballast Valve Control System..............................................4 - 60 4.14 Relief Systems ...............................................................................4 - 62 4.14.1 Cargo Tank Relief Valves....................................................4 - 62 4.14.2 Primary and Secondary Insulation Space Relief Valves......4 - 62 4.14.3 Line Relief Valves ...............................................................4 - 62 4.15 Ballast Piping System ....................................................................4 - 64 4.15.1 General Description ............................................................4 - 64 4.15.2 Ballast Water Management (Ballast Exchange) ..................4 - 65 4.16 Loading Computer .........................................................................4 - 70 4.16.1 ON-Line and OFF-Line Mode ............................................4 - 70 4.16.2 Software Configuration.......................................................4 - 70 4.16.3 Explanation of the Ship Manager Screen ............................4 - 71 4.17 Portable Gas Detector ....................................................................4 - 72 4.17.1 Portable Combination Gas Detector....................................4 - 72 4.17.2 Portable Methane Gas Detector ..........................................4 - 73 4.17.3 Portable Oxygen Monitor....................................................4 - 74 4.17.4 Portable CO2 Analyzer .......................................................4 - 75 4.17.5 Dew Point Meter .................................................................4 - 76 Part 5 Cargo Auxiliary and Deck System 5.1 Temperature Monitoring System........................................................5 - 3 5.2 Insulation Space Nitrogen Control System ........................................5 - 5 5.3 Cofferdam Heating System................................................................5 - 8 5.3.1 Glycol Water Heater................................................................5 - 8 5.3.2 Cofferdam Heating System ...................................................5 - 10 5.3.3 Hull Ventilation .....................................................................5 - 12 5.4 Fire Fighting System........................................................................5 - 14 5.4.1 Fire and Deck Wash System..................................................5 - 14 5.4.2 Water Spray System ..............................................................5 - 16 5.4.3 Dry Powder System ..............................................................5 - 18 5.4.4 CO2 System...........................................................................5 - 22 5.4.5 Fire Detection System...........................................................5 - 23 5.5 Auxiliary F.W. Cooling System........................................................5 - 28 Part 6 Cargo Operations 6.1 Insulation Space Tests........................................................................6 - 2 6.2 Post Dry Dock Operation...................................................................6 - 4 6.2.1 Insulation Space Inerting ........................................................6 - 4 6.2.2 Drying Cargo Tanks ................................................................6 - 8 6.2.3 Inerting Cargo Tanks.............................................................6 - 10 6.2.4 Gassing-up Cargo Tanks .......................................................6 - 12 6.2.5 Cooling Down Cargo Tanks ..................................................6 - 16
3
6.3 Ballast Passage................................................................................ 6 - 18 6.3.1 Cooling Down Tanks prior to Arrival....................................6 - 20 6.3.2 Spraying During Ballast Voyage ...........................................6 - 22 6.4 Loading ........................................................................................... 6 - 24 6.4.1 Preparations for Loading .......................................................6 - 24 6.4.2 Cargo Lines Cool Down........................................................6 - 24 6.4.3 To Load Cargo with Vapour Return to Shore ........................6 - 28 6.4.4 Nitrogen Set-up During Loading...........................................6 - 32 6.4.5 De-Ballasting.........................................................................6 - 34 6.5 Loaded Voyage with Boil-Off Gas Burning .................................... 6 - 36 6.5.1 Normal Boil-Off Gas Burning...............................................6 - 36 6.5.2 Forced Boil-Off Gas Burning................................................6 - 38 6.6 Discharging with the Gas Returning from the Shore ...................... 6 - 40 6.6.1 Preparations for Unloading ...................................................6 - 40 6.6.2 Liquid Line and Arm Cool Down before Discharging ..........6 - 43 6.6.3 Discharging ...........................................................................6 - 46 6.6.4 Ballasting...............................................................................6 - 50 6.7 Pre-Dry Dock Operations................................................................ 6 - 52 6.7.1 Stripping and Line Draining..................................................6 - 52 6.7.2 Tank Warm Up ......................................................................6 - 54 6.7.3 Inerting ..................................................................................6 - 56 6.7.4 Aeration .................................................................................6 - 58 Part 7 Emergency Procedures 7.1 Vapour Leakage................................................................................. 7 - 2 7.2 Liquid Leakage ................................................................................. 7 - 3 7.3 Water Leakage to Barrier Space ........................................................ 7 - 6 7.4 Fire and Emergency Breakaway........................................................ 7 - 6 7.5 Emergency Cargo Pump Installation................................................. 7 - 8 7.6 One Tank Operation ........................................................................ 7 - 12 7.6.1 Warm Up (No.3 Tank) ...........................................................7 - 12 7.6.2 Inerting ..................................................................................7 - 14 7.6.3 Aeration .................................................................................7 - 16 7.6.4 Drying and Inerting ...............................................................7 - 18 7.6.5 Gassing-up Cargo Tank .........................................................7 - 20 7.6.6 Cool Down ............................................................................7 - 22 7.7 Ship to Ship Transfer....................................................................... 7 - 23 7.8 Jettisoning of Cargo ........................................................................ 7 - 24 Part 8 Ship-Shore Item 8.1 General.............................................................................................. 8 - 1 8.1.1 Particulars of Deck Machinery............................................... 8 - 1 8.2 Mooring Facilities ............................................................................. 8 - 5 8.2.1 Performance of Mooring Facilities......................................... 8 - 5 8.2.2 Hydraulic Power System for Deck Machinery....................... 8 - 5 8.2.3 Mooring Arrangements for the LNG Terminal....................... 8 - 6 8.3 Location of Manifold and Details ................................................... 8 - 10 8.4 Location of Landing Area for Shore Gangway ............................... 8 - 12 8.5 Emergency Shutdown and Cargo Tank Protection Scheme ............ 8 - 17 8.6 Ship Shore Link .............................................................................. 8 - 22 8.7 Mooring Load Monitoring System.................................................. 8 - 25
Issue and Update Control
LNGC DISHA
Cargo Operating Manual
Issue and Update Control
Safe Operation
Illustrations
This manual was prepared by:
The safety of the ship depends on the care and attention of all on board. Most safety precautions are a matter of common sense and good housekeeping. These are detailed in the various manuals available on board. However, records show that even experienced operators sometimes neglect safety precautions due to too much familiarity with the ship’s operation. Therefore, the following basic rules must be remembered at all times.
All illustrations are explained in the text and are located either within the text where sufficiently small or above the text, so that both the text and illustration are accessible when the manual is laid face up. When the text concerning an illustration covers several pages, the illustration is duplicated above each page of text.
PENTATECH CO., LTD. For any new issue or update, please contact: Ansan Business Incubator, 932, Wongok-Dong, Danwon-Gu, Ansan-Si, Gyeonggi-Do, Korea E-Mail: [email protected]
1. Never continue to operate any machine or equipment that appears to be potentially unsafe or dangerous. Always report such a condition immediately. 2. Make a point of testing all safety equipment and devices regularly.
Although the ship is supplied with shipbuilder’s plans and manufacturer’s instruction books, there is no single handbook that provides guidance on complete operating systems.
3. Never ignore any unusual or suspicious circumstances, no matter how trivial. Minor symptoms often appear before a major failure occurs.
The purpose of this manual is to fill some of these gaps and to provide the ship’s officers with additional information that is not usually available on board. It is intended to be used in conjunction with the other plans and instruction books already on board and in no way replaces or supersedes them.
4. Never underestimate the fire hazard of petroleum products, whether fuel oil or cargo vapour.
In addition to containing detailed information of the machinery and related systems, the machinery manual provided by each vendor, contains safety procedures, and procedures to be observed in emergencies and after accidents. Used in conjunction with the SMS MANUAL, this information is designed to ensure the safety and efficient operation of the ships. For quick reference to the relevant information, the manual has been subdivided into Parts and Sections, which are detailed in the general list of contents in the preceding pages.
Where flows are detailed in an illustration these are shown in colour. A key of all colours and line styles used in an illustration is provided on the illustration. The details of colour coding used in the illustrations are defined in the colour scheme. The symbols used in the manual adhere to international standards, and keys to the symbols used throughout the manual are given on the following pages. Notices The following notices occur throughout this manual:
5. Never start a machine remotely from the control room without checking visually if the machine can be operated satisfactorily. In the design of equipment and machinery, devices are included to ensure that, as far as possible, in the event of a fault occurring, whether on the part of the equipment or the operator, the equipment concerned will cease to function without danger to personnel or damage to the machine. If these safety devices are neglected, the operation of any machine is potentially dangerous.
Warning Warnings are given to draw the reader’s attention to operation where danger to life or limb may occur. ! Caution Cautions are given to draw the reader’s attention to operations where danger to life or limb may occur. Note ! Notes are given to draw the reader’s attention to points of interest or to supply supplementary information.
Description This book draws reference and other information from appropriate plans or instruction books. For more information, please refer to: 1) Books and Publications contained in the SMS Directory 2) SMS Manual In many cases, the best operating practice can only be learnt by experience. Where the information in this manual is found to be inadequate or incorrect, details should be sent to the Hull Piping Design Team of DSME, so that revisions may be made to the manuals of other ships of the same class.
The concept of this Cargo Operating Manual is based on the presentation of operating procedures in the form of one general sequential chart (algorithm) which gives a step-by-step procedure for performing operations. The manual consists of introductory sections, which describe the systems and equipment that are fitted and their method of operation, related to a schematic diagram, where applicable. This is then followed, where required, by the detailed operating procedures for the system or for the equipment involved. The overview of machinery operations consists of a basic operating algorithm, which sets out the complete procedure for operations, ranging from preparing the plant for operation from dead ship condition, to shutting down the plant in readiness for dry dock. Each machinery operation consists of a detailed introductory section, which describes the objectives and the methods of performing the operation related to the appropriate flow sheet shows the pipelines in use and the directions of flow within the pipelines. The details of valves, which are OPEN during the different operations/functions are provided in the text for reference.
4
Issue and Update Control
LNGC DISHA
Cargo Operating Manual
Cargo Machinery Symbols and Colour Scheme STANDARD SYMBOL VALVE, COCK, STRAINER, PIPE FITTING & INSTRUMENT SYMBOL
DESCRIPTION
SYMBOL
B'FLY LUG TYPE
DESCRIPTION
SYMBOL
OPEN
CLOSE
SYMBOL FM
SEPARATOR
QUICK CLOSING WIRE (STR/ANG) H
DESCRIPTION
FLOW METER
SPECTACLE FLANGE (NORMAL OPENED/CLOSED)
HORN
B'FLY FLANGE TYPE
REM. HD. B'FLY WAFER
ORIFICE PLATE
EJECTER
BALL FULL BORE SOLID
REM. HYD. B'FLY FLANGE
SPOOL PIECE
AUTO FILTER
BALL 3-WAY (T - TYPE/L - TYPE)
SELF CLOSING SPRING (STR./ANG)
AIR VENT GOOSE NECK PIPE
PORTABLE TANK
COCK 2-WAY
SAFETY (STR./ANG)
AIR VENT GOOSE NECK (FLOAT/SCR.)
HULL TANK
COCK 3-WAY ( T - TYPE/L - TYPE)
STORM VERT. SWING CHECK STR.
AIR VENT (FLOAT/FLOAT SCR.)
CENTRIFUGAL PUMP
FLOW CONT. BALL FLOAT
STORM VERT. SWING CHECK STR.
SOUNDING CAP SELF CLOS'G WEIGHT WITH SELF CLOS'G COCK
GEAR PUMP
FLOW CONT. BALL FLOAT CHECK
TEMP. CONROL 2-WAY WAX
SOUNDING CAP NORMAL
HAND PUMP
FLOW CONT. 2-WAY DISC/DIAPHRAGM
TEMP. CONTROL 2-WAY PNEU.
SOUNDING CAP DK PIECE
SCREW PUMP
GLOBE (STR./ANG)
TEMP. CONTROL 3-WAY WAX
SOUNDING CAP SELF CLOS'G WEIGHT PEDAL WITH SELF CLOS'G COCK
MONO PUMP
GLOBE SDNR (STR./ANG)
TEMP. CONTROL 3-WAY ROTARY PISTON
FILLING CAP
PISTON PUMP
SOLENOID 2-WAY (STR.)
TEMP. CONTROL 2-WAY ROTARY PISTON
MUD BOX (ANG./STR.)
VISC. CONTROLLER
GATE NON-RISING
TEMP. CONTROL 3-WAY ROTARY PISTON WITH HANDLE
ROSE BOX
F.W FOUNTAIN
H
HOSE GLOBE (STR./ANG)
GLOBE SDNR WITH HOSE CONNECTOR (STR/ANG) MAGNETIC 2-WAY (STR./ANG)
MAGNETIC 3-WAY
H
WS
WS H WS
REM. HYD. B ' FLY WAFER PISTON WITH HANDLE
WASH BASIN LEVEL GAUGE WITH VALVE (FLAT/CYLINDRICAL TYPE)
WATER SEAL GATE
NON-RETURN FLAP
BELL MOUTH
NON-RETURN SWING
BLANK FLANGE
P
H
P
H
RGB (0, 0, 255)
STRIP LINE
RGB (0, 255, 255)
VAPOUR LINE
RGB (226, 0, 255)
GAS LINE
RGB (253, 253, 0)
STEAM LINE
RGB (255, 0, 0)
N2 LINE
RGB (255, 89, 0)
IG LINE
RGB (74, 74, 74)
LO LINE
RGB (255, 218, 0)
FO LINE
RGB (0, 0, 0)
GLY. W. LINE
RGB (0, 255, 175)
SEA W. LINE
RGB (0, 255, 0)
F.W LINE
RGB (0, 0, 255)
HYD. OIL LINE
RGB (255, 0, 168)
DO LINE
RGB (255, 135,0)
COND. LINE
RGB (0, 0, 255)
AIR LINE
RGB (128, 159, 255)
BILGE LINE
RGB (0, 255, 0)
COLLER PLATE TYPE LEVEL GAUGE (DIAL FLOAT/FLOAT) TYPE OR
MAKER SUPPLY
STEAM TRACING AND INSULATION LEVEL GAUGE WITH VALVE (DIAL TYPE)
NON-RETURN LIFT (STR./ANG)
CARGO LINE
SHELL/TUBE TYPE HEAT EXCH.
WATER SEAL GLOBE (STR)
WATER SEAL REM. ELEC. B ' FLY WATER WITH HANDLE
Symbol Colour
DESCRIPTION
REM. HYD. B'FLY LUG
B'FLY WAFER TYPE
S
STANDARD SYMBOL VALVE, COCK, STRAINER, PIPE FITTING & INSTRUMENT
INSULATION
BOSS AND PLUG
SIGHT GLASS
HYD. OIL PIPE
NON-RETURN BALL WITHOUT SPRING
DRESSER COUPLING
STRAINER Y-TYPE
CONTROL AIR PIPE
NEEDLE STR.
SLEEVE COUPLING
STRAINER SIMPLEX
CAPILLARY TUBE
LOCK (OPEN/CLOSE)
BELLOWS COUPLING
STRAINER DUPLEX
ELECTRIC CABLE
NEEDLE 3-WAY TEST
NOZZLE
STEAM TRAP FLOAT TYPE
DECK
PRESS. CONT. PRIMARY PNEU.
FLEXIBLE HOSE
STEAM TRAP DISC TYPE WITH V/V
PRESS. CONT. REDUCING PNEU.
HOPPER
FILTER REGULATOR
LOCAL INSTRUMENT
PRESS. CONT. REGULAT'G
OVERBOARD
STEAM TRAP BIMETAL TYPE
REMOTE CONTROL INSTRUMENT
QUICK CLOSING PNEU. (STR/ANG)
REDUCER
SEAL POT TANK SIPHON
QUICK CLOSING HYD. (STR/ANG)
BRANCH
LOOP SEAL PIPE SIPHON
5
XS
AUX. SWITCH
Symbols and Colour Scheme
Part 1 Design Concept of Vessel 1.1 Principal Particulars...........................................................................1 - 1 1.1.1 Principal Particulars of the Ship ............................................. 1 - 1 1.1.2 Principal Particulars of Cargo Machinery............................... 1 - 3 1.1.3 Maker List............................................................................... 1 - 4 1.1.4 General Arrangement .............................................................. 1 - 6 1.1.5 Tanks and Capacity Plan ......................................................... 1 - 7 1.2 Rules and Regulations .......................................................................1 - 8 1.3 Design Concept of the Cargo System ..............................................1 - 12 1.3.1 Cargo Containment System Principle ................................... 1 - 12 1.3.2 Membrane Cargo Containment............................................. 1 - 14 1.3.3 Deterioration or Failure ........................................................ 1 - 19 1.4 Hazardous Areas and Gas Dangerous Zone.....................................1 - 21
Part 1 Design Concept of the Vessel
LNGC DISHA Part 1 : Design Concept of Vessel
Cargo Operating Manual Design speed
1.1 Principal Particulars 1.1.1 Principal Particulars of the Ship Shipbuilder
Yard Number Ship Name Delivered Nationality Port of Registration Call Sign Inmarsat-B I.D. TEL TEL TEL TEL TEL TEL FAX DATA HSD TELEX Type of Cargo Type of Ship Stem Stern Navigation Classification
Daewoo Shipbuilding and Marine Engineering Co., Ltd. Okpo Shipyard Republic of Korea 2210 DISHA 2004 Malta Valletta 9HSJ7
321 553 310 Wheel House 321 553 314 Captain 321 553 315 Radio Space 321 553 316 Cargo Control Room 321 553 317 Auto Telephone 321 553 318 321 553 311 321 553 312 391 036 850 321 553 313 LNG Segregated Ballast LNG Carrier Bulbous Bow and Raked Stem Transom Ocean Going Bureau Veritas : I + HULL + MACH, Liquefied Gas Carrier/LNG, Ship type 2G (-163 °C 500 kg/m3 0.25 bar ), Unrestricted Navigation, +VeriSTAR-HULL, + AUT-UMS, + SYSNEQ-1, + MON-SHAFT, INWATERSURVEY IRS (Indian Registry of Shipping) Length Overall 277.0 m Length Between Perpendiculars 266.0 m Breadth Moulded 43.4 m Depth Moulded 26.0 m Design Draught 11.4 m Scantling Draught 12.5 m Cargo Tank Capacity 138,097 m3 Gross tonnage 94058 Tons Net tonnage 28217 Tons Freeboard 8773 mm from deck (Sunken deck) Displacement 100149 Tons at the design draft of 11.4 m Deadweight 70151 Tons at the design draft of 11.4 m
Ballast Draft Cargo Tank Safety Valve Insulation Safety Valve Fuel Oil Consumption per day Guaranteed boil-off rate
19.6 knots with 90% MCR, with 21% sea margin 20.5 knots with 90% MCR, without sea margin 9.4 m 25 kPag 1 kPag 166.8 Tons per day. 0.15% per day
Steering gear Maker Type No. of Sets Torque Hyd. Pump capacity Motor Ballast stripping eductor Type
Main Turbine Maker No. of Sets Type Output Steam Pressure Steam Temperature
Hose handling crane Maker Type No. of Sets Capacity Provision handling crane Maker Type No. of Sets Capacity
TTS MCV1800-10-24Ex Electro-Hydraulic 2 10 Tons
TTS MCV1800-15-16 Electro-Hydraulic 2 15 Tons
Part 1 Design Concept of the Vessel
LNGC DISHA Anchor Maker Type No. of Sets Weight Anchor chain cable Maker Type
Cargo Operating Manual
Kum Hwa Cast Steel HHP 3 13,350 kg
No. of Sets Dimension
Dai Han Anchor Chain Flash butt welded extra high Strength steel (Grade Q3A) 2 102 mm Dia
Air capstan Maker Type No. of Sets Capacity
Yong Nam Marine Mach. Pneumatic type 4 0.5 Tons X 25 m/min.
Fire wire reel Maker Type No. of Sets Wire Rope Size
Yong Nam Marine Mach. Air motor driven type 2 38 mm Dia. X 90 m
Accommodation ladder Maker Type No. of Sets
Sam Gong Co., Ltd. Vertical self stowing type 2
Mooring Rope Type No of Sets Size
6 X 36 IWRC Galv’d 20 + 2(SPARE) 42 mm Dia. X 275 m
1-2
Part 1 Design Concept of the Vessel
LNGC DISHA
Cargo Operating Manual
1.1.2 Principal Particulars of Cargo Machinery Main Cargo Pumps Type; Capacity: No. of sets: Spray/Stripping Pumps Type: Capacity: No. of sets:
Shinko SM350 Rated at 1,650 m3/h x 177 m 8 (2 per cargo tank)
Shinko SM65-2 Rated at 50 m3/h x 160 m 4 (1 per cargo tank)
Emergency Cargo Pumps Type: Shinko SMR200 Capacity: Rated at 550 m3/h x 175 m No. of sets: 1 HD. Compressor Type: Capacity: No. of sets:
Cryostar CM 400/55 32,000 m3/h x 203 kPag 2
LD. Compressor Type: Capacity: No. of sets:
Cryostar CM 300/45 8,000 m3/h x 196 kPag 2
LNG Vapourizer Type: Mass flow Heating: No. of sets:
Cryostar 65-UT-38/34-5.9 10,788 kg/h Steam at 700 kPag 1
Forcing Vapourizer Type: Mass flow: Heating: No. of sets:
Cryostar 34-UT-25/21-3.6 6,790 kg/h Steam at 800 kPag 1
High Duty Gas Heaters Type: Mass flow: Heating: No. of sets:
Cryostar 108-UT-38/34-3.8 22,600 kg/h Steam at 700 kPag 1
Low Duty Gas Heaters Type: Mass flow: Heating: No. of sets:
Cryostar 21-UT-38/34-3.2 7,906 kg/h Steam at 700 kPag 1
Mist Separator Type: Mass flow: No. of sets:
Cryostar VMS-10/12-1000 5,800 kg/h 1
Vacuum Pumps Type: Capacity: No. of sets:
MPR industries P100 1,250 m3/h 2
Steam Heater for Glycol Water Type: BEU 323-1800 Capacity: 130L (steam) / 57L (glycol) Heating: Steam at 700 kPag No. of sets: 2 Electric Heater for Glycol Water Type: TB100E Capacity: 80 kW x 440V Heating: Electric No. of sets: 1 Nitrogen Generator Type: Capacity: Dew point: Outlet pressure(min/max): No. of sets:
Air Products Nitrogen Generator 120 Nm3/h at 97%N2 -70 °C 600/950 kPag 2
Nitrogen Buffer Tank Capacity: Working Pressure: Hydrostatic test pressure: No. of sets:
37 m3/h 1 MPag 1.5 MPag 1
Inert Gas Generator Type: Capacity: Inert Gas Dry Air Inert Gas/Air Dew Point: Delivery Pressure: Max. 0₂content: No. of sets:
Safety Valve for Primary Insulation Spaces Type: Fukui 6” x 6” Capacity: 2,146 Nm3/h Set Pressure: 1 kPag No. of sets: 8 Safety Valve for Secondary Insulation Spaces Type: Fukui 6” x 6” Capacity: 2,146 Nm3/h Set Pressure: 1 kPag No. of sets: 8 Drain cooler Type: Capacity: No of sets:
Shell / Tube Type 95 m3/h 1
Cargo Machinery Room Exhaust Fan Type: MXDN-1000/410 Air Volume: 48,000 m3/h No. of sets: 2 Cargo Motor Room Supply Fan Type: AQ-800/380 Air Volume: 21,000 m3/h No. of sets: 2 Cargo Hoses Temp. Range: Working Pressure: Capacity: No. of sets:
-200 °C up to +80 °C 1MPag/150 psig 8” X 4m 4
Safety Valve for Cargo Tank Type: Fukui 10” x 12” Capacity: 27,700 Nm3/h Set Pressure: 25 kPag No. of sets: 8
1-3
Part 1 Design Concept of the Vessel
LNGC DISHA
Cargo Operating Manual
1.1.3 Maker List NO.
1) Hull Part NO. 1
EQUIPMENT CRYOGENIC HOSE
MAKER FLEXTRACO. B.V.
DWG NO. DV3010101
MAKER ADDRESS & TELEPHONE FLEXTRACO B.V
TEL. 31-0-10-521-5422
SAMBONG CO.
CHR.
FAX. 31-0-10-521-8420
TEL. 02-839-2322
HUXGENSSTRAATIOA2665
13
AGENT
14
FAX. 02-839-2335
3
ILJIN AND CO.
NOZZLE
KOREA
CARGO PUMP
SHINKO IND, LTD.
DV8140104
1500-8,
15
DV3510101
5
LNG VAPORISER
FORCING VAPORISER
CRYOSTAR-
5-7-21, OHZU, MINAMI-KU, TEL. 082-508-1000
SAMKONG TRADING
HIROSHIMA JAPAN
TEL. 051-246-7793
FAX. 082-508-1020
ZONE INDUSTRIELLE BP48 TEL. 33-389-70-2727
TACHYON CO.
FRANCE SA
F-68220
TEL. 02-514-4516
FRANCE
FRANCE
CRYOSTAR-
DV3510102
DV3510102
FRANCE SA
6
GAS HEATER
CRYOSTAR-
DESINGUE, FAX. 33-389-70-2900
ZONE INDUSTRIELLE BP48 TEL. 33-389-70-2727 DESINGUE, FAX. 33-389-70-2900
Location Frame Number 138-157 48-71 67-71 48-67 60-63 48-60 48-60
Total
S.G.=0.980 Capacities
Center of Gravity
Volume 3 100% (m )
Weight 98% (Tons)
L.C.G. (m)
V.C.G. (m)
3533.9 1009.6 261.7 709.9 38.0 225.6 225.6
3393.9 969.6 251.3 681.8 36.5 216.7 216.7
110.14 -83.59 -77.80 -85.71 -83.80 -89.80 -89.80
12.81 16.59 16.07 16.71 17.97 19.57 19.57
6004.3
5766.5
Diesel Oil Tanks Compartment
DO. Stor. Tk(P) DO. Serv. Tk(P) DO. Tk for IGG Total
1-7
Location Frame Number 40-47 44-47 40-47
Max. F.S.M. 4 M 2798 102 18 84 3 11 11
S.G.=0.850 Capacities Volume 3 100% (m )
Center of Gravity
Weight 98% (Tons)
332.7 37.7 131.3
277.1 31.4 109.4
501.7
417.9
L.C.G. (m)
V.C.G. (m)
-98.15 -96.60 -98.66
16.30 23.72 23.68
Max. F.S.M. 4 M 115 6 85
Part 1 Design Concept of the Vessel
LNGC DISHA
Cargo Operating Manual
Lubricating Oil Tanks Compartment
Main LO. Grav. Tk(S) Main LO. Sett. Tk(S) Main LO. Stor. Tk(S) D/G LO. Stor. Tk(S) D/G LO. Sett. Tk(S) T/G LO. Stor. Tk(S) T/G LO. Sett. Tk(S) Main LO. Sump Tk(C)
Classification The vessel, including her hull, machinery, equipment and outfits shall be constructed under the survey of the Bureau Veritas (herein called the “Classification Society”), and shall be distinguished in the register by the symbols of: I + HULL + MACH, Liquefied Gas Carrier/LNG, Ship type 2G (-163 °C 500 kg/m3 0.25 bar ), Unrestricted Navigation, +VeriSTAR-HULL, + AUT-UMS, + SYS-NEQ-1, + MON-SHAFT, INWATERSURVEY The vessel shall be classed with the Indian Registry of Shipping (IRS) with equivalent notations.
Rules and Regulations The Vessel shall be registered in the above port and shall comply with the following Rules and Regulations. All rules and regulations of the country of registry, the classification society, and the relevant government authorities of India and Qatar, known at the time of signing of the contract and are enforceable at any time within 5 years from the date of the delivery of the vessel, shall be implemented prior to delivery. a)
Rules and Regulations of the country of registry and the Indian registry.
cc) IMO Resolution A.868(20) “Guidelines for the control and Management of Ship’s Ballast Water to Minimize the Transfer of Harmful Aquatic Organisms and Pathogens (except ballast water management plan)”.
k) ILO Convention concerning Crew Accommodation on Board Ship (No. 92 and 133). l)
Certificates
ILO Codes of Practice, Safety and Health in Dockwork, 1977 as amended in 1979.
The Builder shall obtain the following certificates and deliver to the Owner at the time of the Vessel’s delivery in triplicate, one (1) original and two (2) copies:
m) DNV notation F-AMC for structural fire protection and equipment except Pt. 6 ch.4 Sec.2 B201 and C100. n) OCIMF “Standardization of Manifolds for Refrigerated Liquefied Gas Carriers (LNG)”. o) OCIMF “Mooring Equipment Guidelines, 1997 (Compliance with the Guidelines shall be as specified in Group 4)”. p) OCIMF “Ship to Ship Transfer Guide (Liquefied gases)”. q) SIGTTO “Guidelines for the Alleviation of excessive Surge Pressure on ESD, 1987. r)
SIGTTO “Recommendations and Guidelines for Linked Ship/Shore Emergency Shutdown of Liquefied Gas Cargo Transfer”.
b) Maritime Rules and Regulations of the loading/unloading ports.
s)
SIGTTO “Recommendations for the Installation of Cargo Strainers”.
c)
t)
IMO Resolution A.330(IX) “Safe Access to working in large ballast space”.
International Convention on Load Lines, 1996 with the Protocol of 1988.
bb) IMO Circular letter No. 2224 dated at 26th May 2000 (Amendments to the International Convention for the Safety of Life at Sea, 1974, as amended (SOLAS)).
Rules and Regulations of USCG for Foreign Vessels Operating in the Navigable Waters of the United States including pollution prevention except in Alaskan waters. . CFR title 33-part 155, 156, 159 and 164 . CFR title 46-part 154
a)
Builder’s Certificate issued by the Builder.
b)
Classification Certificate issued by the Classification Society.
c)
International Load Line Certificate issued by the Classification Society.
d)
International Tonnage Certificate issued by the Classification Society or other assigned Authority.
e)
International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk issued by the Classification Society or other assigned Authority.
f)
International Oil Pollution Prevention Certificate issued by the Classification Society or other assigned Authority.
g)
Suez Canal Special Tonnage Certificate issued by the Classification Society or other assigned Authority.
h)
Cargo Ship Safety Radio certificate issued by the Classification Society or other assigned Authority.
d) International Convention for the Safety of Life at Sea, 1974 with the Protocol of 1978/1988 and Amendments up to 1997 including International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC-code).
u) IMO Resolution A.468(XII) “Code on Noise Levels on Board Ships”. v) IMO Resolution A.601(15) “Provision and Display of Manoeuvring Information on Board Ships”.
i)
Cargo Ship Safety Construction Certificate Classification Society or other assigned Authority.
e)
International Convention for the Prevention of Pollution from Ships, 1973 (Annex I, IV, V & VI (Regulation 12, 13 and 16)), as modified by the Protocol 1978 and Amendments up to 1997 (herein called “MARPOL 73/78”).
w) IMO Resolution A.686(17) “Code on Alarms and Indicators”.
j)
Cargo Ship Safety Equipment Certificate issued by the Classification Society or the assigned Authority.
k)
Convention on the International Regulations for Preventing Collisions at Sea, 1972 with the Amendments up to 1993.
y) IEC publication 533 “Electromagnetic Compatibility of Electrical and Electronic installation on Ships”.
Statement of compliance with USCG Rules and Regulations for Foreign Vessels carrying liquefied gases in bulk issued by the Classification Society.
l)
Statement of Compliance of EIAPP for Auxiliary Engine issued by the Classification Society or other assigned Authority.
m)
Statement of Compliance of MARPOL Annex VI for Incinerator issued by the Classification Society or other assigned Authority.
f)
g) International Convention on Tonnage Measurement of Ships, 1969. h) International Telecommunication Convention, 1973 with annex and revisions 1974, 1982 and 1983/87. i)
Rules of Navigation of the Suez Canal Authority including Regulations for the Measurement of Tonnage.
x) International Electrotechnical Commission “Electrical installation in Ships”.
z)
(IEC)
Publication
92
ISO Draft Proposal No. 6954 “Guidelines for Overall Evaluation of Vibration in Merchant Ships, 1984”.
aa) VDI 2056 “Criteria for Assessment of Mechanical Vibrations in Machines”.
1-9
issued
by
the
Part 1 Design Concept of the Vessel
LNGC DISHA n)
Statement of Compliance of IAPP for Nox issued by the Classification Society or other assigned Authority.
o)
Deratting Exemption Certificate issued by the Korean Government.
p)
Cargo gear Certificate corresponding to ILO forms issued by the Builder for Provision Cranes and Deck Cranes.
q)
Adjustment certificates for magnetic compass issued by the Builder.
r)
Crew Accommodation Certificate corresponding to ILO Convention No.92 and 133 issued by the Classification Society or other assigned Authority.
s)
Certificates for all Custody Transfer Instruments and Cargo Tank Calibration Tables issued by Independent Society mutually agreed between the Owner and the Builder.
t)
Statement of compliance of F-AMC for structural Fire protection and Equipment only except pt.6 ch.4 Sec.2 B201 and C100.
u)
Other Certificates including Manufacturer’s Certificates and Builder’s Certificates which are normally issued for Machinery, Equipment and Outfit of the Vessel.
Cargo Operating Manual
The Builder shall provide with necessary assistance in preparing for and obtaining approval from the government authorities of the loading and discharging port for calibration of CTS and cargo tank table. If the formal certificate(s) are not obtained at the time of the Vessel’s delivery, the Builder shall furnish the Owner with the provisional certificate(s). In such case(s), the Builder shall deliver the formal certificate(s) to the Owner as soon as available after the Vessel’s delivery.
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Part 1 Design Concept of the Vessel
LNGC DISHA
Cargo Operating Manual
Illustration 1.3.1a Cargo Tank Lining Reinforcement
Void Area
Cofferdam Reinforced Area Secondary boxes........... Type RS Primary boxes................ Type RP
Primary Membrane
Secondary Membrane
Non Reinforced Area Secondary boxes........... Type S Primary boxes................ Type P
Ballast
Primary Insulation Boxes
Void Cofferdam
Secondary Insulation Boxes
Pipe Duct Ballast Tank
Pipe Duct
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Part 1 Design Concept of the Vessel
LNGC DISHA
Cargo Operating Manual
1.3 Design Concept of the Cargo System
1.3.1 Cargo Containment System Principle
General Description
The cargo tanks are of double membrane, Gaz Transport No.96-2 Evolution System design.
The Cargo Containment System consists of four double insulated cargo tanks encased within the inner hull and situated in-line from forward to after. The spaces between the inner hull and outer hull are used for the ballast and will also protect the tanks in the event of an emergency situation, such as collision or grounding. The cargo tanks are separated from other compartments, and from each other, by five transverse cofferdams, which are all dry compartments. The ballast spaces around the cargo tanks are divided into two double bottom water ballast tanks, two wing water ballast tanks, port and starboard for each cargo tank. The wing water ballast tanks extend to the side of the cargo tanks and as far up as the trunk ways. The LNG to be transported is stored in the four cargo tanks numbered 1 to 4, from fore to aft. All cargo tanks have an octagonal transverse section matching with the supporting inner hull. Each tank between the two transverse bulkheads is composed of a prism placed in a direction parallel to the keel plate. The boundaries of the tanks are as follows: 1) One flat bottom, parallel to the keel plate raised along the ship’s plating by two inclined plates, one on each side. 2) Two vertical walls each extended at their upper parts by an inclined plate, in order to limit the liquid free surface effect when the tanks are full. 3) One flat top parallel to the trunk bottom. Cargo tank No.1 is slightly different in shape due to its position in the ship. It has a polygonal section and the lengthwise walls are almost parallel to the ship’s plating.
Thermal expansion coefficient = (1.5±0.5) 10-6 mm/°C between 0°C and –180°C (Less than approx. ten times for stainless steel AISI 304 type) Charpy Test at -196°C, > 120 J/cm2
The inner hull, i.e. the outer shell of each of the cargo tanks, is lined internally with the Gaz Transport integrated tank containment and insulation system. This consists of a thin, flexible membrane called the primary membrane, which is in contact with the cargo, a layer of plywood boxes filled with Perlite called the Primary insulation, a second flexible membrane similar to the first one called the secondary membrane and a second layer of boxes also filled with Perlite in contact with the inner hull called the Secondary insulation. The double membrane system meets the requirement of the relevant regulations on the Cargo Containment System to provide two different ‘barriers’ to prevent cargo leakage.
The coefficient of thermal expansion is low enough to enable flat, rather than corrugated sheets, to be used. The entire surface area of the membrane is thus in contact with the supporting insulation, so that the load which the system is able to carry is limited only by the load bearing capacity of the insulation.
Thus, the tank lining consists of two identical layers of membranes and insulation so that in the event of a leak in the primary barrier, the cargo will be contained indefinitely by the secondary barrier. This system ensures that the whole of the cargo hydrostatic loads are transmitted through the membranes and insulation to the inner hull plating of the ship.
Perlite is obtained from a vitreous rock of volcanic origin which, when heated to a high temperature (above 800°C), is transformed into very small balls. These balls have diameters that measure between a few hundredths to a few tenths of a millimeter. The cellular structure so obtained from the process gives the expanded Perlite its lightness and thus its excellent insulation properties. The water repellency of the Perlite is reduced by a silicon treatment.
The function of the membranes is to prevent leakage, while the insulation supports and transmits the loads and, in addition, minimizing heat exchange between the cargo and the inner hull. The secondary membrane, sandwiched between the two layers of insulation, not only provides a safety barrier between the two layers of insulation, but also reduces the convection currents within the insulation. The primary and secondary insulation spaces are under a pressure controlled nitrogen atmosphere. The primary space’s pressure must never exceed the cargo tank pressure in order to prevent the primary membrane from collapsing inwards. In normal operation, the pressure in the primary and secondary insulation spaces shall be maintained between 0.2 kPag and 0.4 kPag. Construction of the Insulation and Barriers The primary and secondary barriers are identical and are fabricated from cryogenic invar 36% nickel steel, with a very low coefficient of thermal expansion, 0.7 mm thick). The composition of the invar is as follows: Ni C Si Mn S P Fe
: : : : : : :
The primary and secondary insulation spaces are made up of boxes fabricated from plywood and filled with expanded Perlite. This insulation system allows free circulation of nitrogen and therefore permits gas freeing or inerting to be carried out in the barrier spaces without difficulty.
The insulation is distributed over the hull in two specific areas : 1) Reinforced area located in the upper part of the tank and covering approximately 30% of the total tank height (including the tank ceilings). This area is fitted with reinforced type boxes. 2) Standard area (or non-reinforced area) covering approximately 70% of the tank height (including the tank bottom). This area is fitted with normal boxes (refer to Illustration 1.3.1a). The secondary and primary boxes in the reinforced area are specially built using thicker internal stiffeners to resist the impact that can be created by the liquid sloshing inside the tanks. The primary reinforced boxes have two 12 mm thick plywood covers stapled on it. The secondary insulation is 300 mm thick, whereas the primary insulation is 230 mm is thick. (The designed boil-off rate, i.e. 0.15% of the total cargo tanks, and volume per day govern the thickness).
Secondary Barrier (INVAR : 0.7mm) Primary Insulation Box(230mm) Liquid Dome
Primary Barrier(INVAR : 0.7mm)
Vapour Dome
Discharge Line
Filling Line Tripod Mast
Main Cargo Pumps Ballast Tanks
Pipe Duct
Stripping/Spray Pump
INVAR : Fe-36% Nickel Alloy
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Part 1 Design Concept of the Vessel
LNGC DISHA 1.3.2 Membrane Cargo Containment The plywood boxes forming the secondary insulation are laid on the ship’s inner hull, through the transition of a hard epoxy bearing product deposited on the box in the shape of ropes by means of an automatic depositing machine. These ropes have adjustable thickness and compensate for the flatness defects of the inner hull. The boxes are held in position by stainless steel coupler rods that are anchored to the inner hull through their welded sockets. To absorb the ship’s hull deformation, each coupler is fitted with an elastic coupling made up of several spring washers, which are tightened down on the setting plates for secondary boxes by securing nuts (refer to Illustration 1.3.2a). The number of spring washers used depends on the location of the box. Boxes on the ballast boundaries have a higher number of spring washers (5) because the hull deformation has the largest effect on this area. A continuous invar tongue is held in slots running along the whole length of each secondary box cover. The secondary membrane strakes are resistance seam welded with the continuous tongues in between.
Cargo Operating Manual With this system, the membranes are directly connected to the inner hull so that any membrane tension is directly and uniformly taken by the ship’s structure (refer to illustrations 1.3.2b and 1.3.2c). In the secondary and primary insulation spaces respectively, the gaps between the secondary boxes and the primary boxes are insulated with a combination of rigid insulating materials and glasswool.
Punching Device If the primary membrane is damaged and leaks LNG into the primary insulation space, to avoid catastrophic damage to the primary membrane the punching device shall be used before discharging the tank. See section 7.2. The inspection chamber and gauge header is removed and the punching messenger device is fitted on the gate valve. When dropped through the gate valve, the messenger device punches through the primary membrane.
Cargo Tank Outfitting
Actual data measured by ITS/NKK. Unit : mm
A vapour dome is located near the geometrical center of each cargo tank ceiling. Each vapour dome is provided with the following: 1) A vapour supply/return line to supply vapour to the tank when discharging, vent vapour from the tank whilst loading and also vent the boil-off when the tank contains cargo.
TANK NO.
A
B
C
D
E
1
940
420
92
62
21
2
920
420
94
64
21
3
920
420
96
66
21
4
930
420
94
64
21
2) Spray line arrangement for cooldown purposes.
A : Distance to aft bulk head from the gauge
The primary boxes are secured in position by collar studs. The collar studs are screwed into setting (clamp) plates for collar studs linked to the setting plate for secondary boxes by two securing screws. A plywood bridge is installed between the two setting plates to limit any thermal conduction through the box fixations.
3) Two pressure/vacuum relief valves set at 25kPa and –1kPa, venting to the nearest vent mast.
B : Distance to center line of vessel (to starboard)
To allow some flexibility, each collar stud is fitted with an elastic coupling, similar to those on the secondary boxes.
5) Liquid line safety valves exhaust.
Each collar stud is fitted with a single spring washer and tightened down on the setting plate for primary boxes by securing nuts. The primary insulation boxes have lipped invar tongues stapled along slots running lengthwise. Continuous invar tongues are positioned in the lip of the fixed tongues on the boxes. The primary membrane strakes are resistance seam welded with these tongues in between. Each primary and secondary membrane strake terminates on an invar angle structure, 1.5 mm thick, fitted around the perimeter of each transverse bulkhead and welded to it. Due to their superposition, the secondary and primary membranes cross each other in both ways, forming a square tube. This is prefabricated to allow an easier erection process and attached to the double hull by 4 anchoring bars.
C : Level above true zero where float becomes buoyant in liquid with a density of 470 kg/m3.
4) Pick-up for pressure sensors.
In addition, each cargo tank has a liquid dome located near the ship’s center line at the aft part of the tank. The liquid dome supports a tripod mast made of stainless steel (304 L), suspended from the liquid dome and held in position at the bottom of the tank by a sliding bearing to allow for thermal expansion or contraction depending on the tank environment. The tripod mast consists of the main discharging pipes and emergency pump well, in the form of a three-legged trellis structure, and is used to support the tank access ladder and other piping and instrumentation equipment.
The level gauge is correctly set when, at an average tank temperature of 15°C, with the float resting on the float support, value “C” is obtained as reading. D : Level above true zero of the float support attached to the stilling well. E : Immersion of the float in a liquid with a density of 470 kg/m3
The instrumentation includes temperature and level sensors, independent high level alarm sensors and cargo pump electric cables. The two main cargo pumps are mounted on the base plate of the tripod mast, while the stripping/spray pump is mounted on the pump tower support. An emergency pump column, a float gauge column and the filling line are also located in the liquid dome. The four cargo tanks are connected to each other by the liquid, vapour and stripping/spray headers which are located on the trunk deck. The nitrogen mains supplying the primary and secondary insulation spaces, and other services directly associated with the cargo system, are also located on the trunk deck together with the fire main and deck spray main.
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Part 1 Design Concept of the Vessel
LNGC DISHA
Cargo Operating Manual
Illustration 1.3.2a Construction of Containment System– Securing of Insulation Boxes
Primary Membrane
Setting Plate For Primary Box Setting Plate For the Collar Stud
Fabric Seal Plywood Bridge Primary Box
Bearing Product
Stainless Steel Plate Spot Welded To Nut
Bevel Washer Secondary Membrane
Setting Plate For Secondary Box
Secondary Box Insulating Material
Secondary Box
Bearing Product Packing Washers
Paper Packing Double Hull Plating
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Part 1 Design Concept of the Vessel
LNGC DISHA
Cargo Operating Manual
Illustration 1.3.2b Construction of Containment System – Flat Area
Plywood Box Cover Primary Invar
Primary Box Insulating Material Insulating material
Insulating Material
Plywood Bridge Insulating Material Wedge
Perlite Insulation
Packing Washers Secondary Box
Secondary Invar
Epoxy Rope Bearing Product
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Part 1 Design Concept of the Vessel
LNGC DISHA
Cargo Operating Manual
Illustration 1.3.2c Construction of Containment System – Corner Part
Illustration 1.3.2.d Construction of Containment System – Longitudinal Dihedral
Primary Box Secondary Box
Position of Longitudinal Dihedral
Primary Membrane
Secondary Membrane
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Part 1 Design Concept of the Vessel
LNGC DISHA 1.3.3 Deterioration or Failure The insulation system is designed to maintain the boil-off losses from the cargo at an acceptable level, and to protect the inner hull steel from the effect of excessively low temperature. If the insulation efficiency should deteriorate for any reason, the effect may be a lowering of the inner hull steel temperature, i.e. a cold spot and an increase in boil-off from the affected tank. Increased boil-off gas may be vented to the atmosphere via No.1 vent mast. The inner hull steel temperature must, however, be maintained within acceptable limits to prevent possible brittle fracture. Thermocouples are distributed over the surface of the inner hull, but unless a cold spot occurs immediately adjacent to a sensor, these can only serve as a general indication of steel temperature. To date, the only reliable way of detecting cold spots is by frequent visual inspections of the ballast spaces on the loaded voyage.
Cargo Operating Manual If a cold spot is detected either by the inner hull temperature measurement system, or by visual inspection, the extent and location of the ice formation should be recorded. Small local cold spots are not critical and, provided a close watch and record are kept as a check against further deterioration and spreading of the ice formation, no further action is required. If the cold spot is extensive, or tending to spread rapidly, salt water spraying should be carried out. In the unlikely event that this remedy is insufficient and it is considered unsafe to delay discharge of cargo until arrival at the discharge port, the final recourse will be to jettison the cargo via a spool piece fitted at the cargo liquid manifold, using a single main cargo pump.
Illustration 1.3.3a Hull Steel Grades A
The grade of steel required for the inner hull of the vessel is governed by the minimum temperature this steel will reach at minimum ambient temperature, assuming that the primary barrier has failed, so that the LNG is in contact with the secondary membrane.
E E
A
A
E
For the contiguous hull, environmental conditions are issued from the USCG rules. y Air temperature = -18°C y Sea water temperature = 0°C y Wind speed = 5 knots y LNG in contact with the secondary barrier. For the outer hull, conditions are based on IGC y Air temperature = 5°C y Sea water temperature = 0°C y No wind y LNG in contact with the secondary barrier The minimum temperature of the inner steel will be about -26°C. For these conditions, Classification Societies require a steel grade distribution as shown in Illustration 1.3.3a, where the tank top and top longitudinal chamfer are in grade ‘E’ steel, and the remaining longitudinal steelwork grade ‘DH’, both grades having a minimum operating temperature of –30°C. The transverse watertight bulkheads between cargo tanks are of grade ‘A’ with glycol water heating system.
E
DH
A
E
DH
A
DH
D
D A
In addition to the failure of the membrane, local cold spots can occur due to failure of the insulation.
Pipe Duct
Watertight Bulkhead Between Cargo Tanks
Minimum Operating Temp
While the inner hull steel quality has been chosen to withstand the minimum temperature likely to occur in service, prolonged operation at steel temperatures below 0°C will cause ice build-up on the plating, which in turn will cause a further lowering of steel temperature due to the insulating effect of the ice. To avoid this, glycol heating coils are fitted in the cofferdam spaces, of sufficient capacity to maintain the inner hull steel temperature at 0°C under the worst conditions.
Grade A -5
A
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A
and maximum plate thickness
15mm
Grade E -30
40mm
Grade D -20
20mm
Grade EH -30
40mm
Grade DH -30
20mm
Part 1 Design Concept of the Vessel
LNGC DISHA
Cargo Operating Manual
Illustration 1.4a Hazardous Areas and Gas Dangerous Zone Plan
NO SMOKING NO SMOKING
+AUT-UMS
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Part 1 Design Concept of the Vessel
LNGC DISHA 1.4 Hazardous Areas and Gas Dangerous Zone (See Illustration 1.4a) Under the IMO code for the Construction and Equipment of Ships Carrying Gases in Bulk, the following are regarded as hazardous areas: Gas dangerous spaces or zones, are zones on the open deck within 3.0 m of any cargo tank outlet, gas or vapour outlet, cargo pipe flange, cargo valve and entrances and ventilation openings to the cargo compressor house. They also include the open deck over the cargo area, and 3.0 m forward and after of the cargo area on the open deck up to a height of 2.4 m above the weather deck, and a zone within 2.4 m of the outer space of the cargo containment system where such spaces are exposed to the weather.
Cargo Operating Manual All electrical equipment sited in hazardous areas is of the intrinsically safe type. Fresh air intakes, supply and exhaust ventilators for the cargo machinery room, cargo electric motor room, side passage and pipe duct are provided. When testing enclosed spaces for the presence of natural gas, it is important to ensure that pockets of gas are not trapped near deckhead structure, etc. In the case of a leak or spillage of LNG the following procedure must be carried out ; 1) Isolate the source of LNG. If loading or discharging, stop a operations and close the manifold valves. 2) Summon assistance by sounding the alarm. 3) Protect hull form possible risk of cold fracture.
The entire cargo piping system and cargo tanks are also considered gas dangerous. In addition to the above zones, the Code defines other gas-dangerous spaces. The area around the air-swept trunking, in which the gas fuel line to the engine room is situated, is not considered a gas dangerous zone under the above Code. All electrical equipment used in these zones, whether a fixed installation or portable, is certified ‘safe type equipment’. This includes intrinsically safe electrical equipment, flame-proof type equipment and pressurized enclosure type equipment. Exceptions to this requirement apply when the zones have been certified gas free, e.g. during refit. Safety Precaution The piping system fitted on board enables the cargo system to be operated safely. Provided that certain procedures are followed. Since flammable gases are involved, inert gas or nitrogen gas is used to eliminate the possibility of an explosive mixture existing in the cargo system during any part of the gas-freeing operation. The system will also enable the cargo tanks to be purged with inert gas or nitrogen prior to filling with cargo tanks. The piping has been arranged to eliminate the possibility of pockets of gas or air remaining after gas-freeing or purging. The gas freeing process follows a distinct cycle from cargo vapour, to inert gas, to air, is displaced by good quality inert gas before air is introduced into the tanks. The reverse procedure is adopted when preparing the ship for resumption of service after dry docking or lay-up. Boil-off gas is supplied to the main boilers through an air-swept trunk that is continuously monitored for gas leakage. Any interruption or failure of the gas supply initiates a closure of the gas supply and an automatic nitrogen purge of the whole engine room gas supply system.
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Part 1 Design Concept of the Vessel
Part 2 Properties of LNG 2.1 Physical Properties, Composition and Characteristics of LNG .........2 - 1 2.2 Characteristics of LNG ......................................................................2 - 4 2.2.1 Flammability of Methane, Oxygen and Nitrogen Mixtures ....2 - 4 2.2.2 Supplementary Characteristics................................................2 - 5 2.2.3 Properties of Nitrogen and Inert Gas ......................................2 - 6 2.2.4 Avoidance of Cold Shock to Metal .........................................2 - 8 2.3 Health Hazards ..................................................................................2 - 9
Part 2 Properties of LNG
LNGC DISHA
Cargo Operating Manual
Part 2 Properties of LNG 2.1 Physical Properties, Composition and Characteristics of LNG Natural gas is a mixture of hydrocarbons which, when liquefied, form a clear colourless and odourless liquid. This LNG is usually transported and stored at a temperature very close to its boiling point at atmospheric pressure . (approximately –160°C) The actual LNG composition of each loading terminal, such as Qatar and e.g. Abu Dhabi, will vary depending on its source and on the liquefaction process, but the main constituent will always be methane. Other constituents will be small percentages of heavier hydrocarbons, e.g., ethane, propane, butane, pentane, and possibly a small percentage of nitrogen. A typical composition of LNG is given in Table 2.1b, and the physical properties of the major constituent gases are given in Table 2.1a. For most engineering calculations (e.g. piping pressure losses), it can be assumed that the physical properties of pure methane represent those of LNG. For custody transfer purposes, however, when accurate calculation of the heating value and density is required, the specific properties based on actual component analysis must be used. During a normal sea voyage, heat is transferred to the LNG cargo through the cargo tank insulation, causing vapourization of part of the cargo, i.e. boil-off.
The composition of the LNG is changed by this boil-off because the lighter components, having lower boiling points at atmospheric pressure, vapourize first. Therefore the discharged LNG has a lower percentage content of nitrogen and methane than the LNG as loaded, and slightly higher percentages of ethane, propane and butane, due to methane and nitrogen boiling off in preference to the heavier gases.
Table 2.1b Composition of LNG Ras Laffan
Das Islands
Standard
Methane
(mol %)
CH4
90.28
84.5
89.63
Ethane
(mol %)
C2H6
6.33
12.9
6.32
n-C3H8
2.49
1.5
2.16
n-C4H10
0.49
0.5
1.20
The flammability range of methane in air (21% oxygen) is approximately 5.3 to 14% (by volume). To reduce this range, the air is diluted with nitrogen until the oxygen content is reduced to 2% prior to loading after dry docking. In theory, an explosion cannot occur if the O2 content of the mixture is below 13% regardless of the percentage of methane, but for practical safety reasons, purging is continued until the O2 content is below 2%. This safety aspect is explained in detail later in this section.
Propane
The boil-off vapour from LNG is lighter than air at vapour temperatures above -110°C or higher, depending on the LNG’s composition (See Fig. 2.1d), Therefore, when vapour is vented into the atmosphere, the vapour will tend to rise above the vent outlet and will be rapidly dispersed. When cold vapour is mixed with ambient air, the vapour-air mixture will appear as a readily visible white cloud due to the condensation of the moisture in the air. It is normally safe to assume that the flammable range of the vapour-air mixture does not extend significantly beyond the perimeter of the white cloud.
Average Molecular Weight
Butane
(mol %) (mol %)
Iso-Butane
(mol %)
i-C4H10
0.00
0.00
0.00
Pentane
(mol %)
n-C5H12
0.02
0.00
0.00
Iso-Pentane
(mol %)
i-C5H12
0.00
0.00
0.00
Nitrogen
(mol %)
N2
0.41
0.6
0.69
17.88
18.56
18.12
-160.8°C
-161.0°C
-160.9°C
461.8
456.8
459.4
54,414
54,031
54,090
Boiling Point at Atmospheric Pressure Density (kg/m3) Higher Specific Energy (kJ/kg)
The auto-ignition temperature of methane, i.e. the lowest temperature to which the gas needs to be heated to cause self-sustained combustion without ignition by a spark or flame, is 595°C. Table 2.1c Properties of Methane Boiling point at 1 bar absolute (0.1MPaA)
Table 2.1a Physical Properties of LNG
-161.5°C 426.0 kg/m3
Liquid density at boiling point
Molecular Weight
Methane
Ethane
Propane
Butane
Pentane
Nitrogen
CH4
C2H6
C3H8
C4H10
C5H12
N2
16.042
30.068
44.094
58.120
72.150
28.016
Boiling Point at 1 bar absolute
°C
-161.5
-88.6
-42.5
-5
36.1
-196°C
Liquid Density at Boiling Point
Kg/m3
426.0
544.1
580.7
601.8
610.2
808.6
0.554
1.046
1.540
2.07
2.49
0.97
619
413
311
311
205
649
3 to 12.4
Nonflammable
Vapour SG at 15°C and 1 bar absolute Gas volume/liquid volume Ratio at Boiling Point and 1 bar absolute Flammable Limits in air by Volume
%
5.3 to 14
3 to 12.5
2.1 to 9.5
2 to 9.5
Auto – Ignition Temperature
°C
595
510
510/583
510/583
Gross Heating Value at 15°C normalIso -
kJ/kg
55,550
51,916
50,367
49,530 49,404
49,069 48,944
Vaporization Heat at Boiling Point
kJ/kg
510.4
489.9
426.2
385.2
357.5
2-1
Vapour SG at 15°C and 1 bar absolute (0.1MPaA)
0.554
Gas volume/liquid volume ratio at -161.5°C at 1 bar absolute (0.1MPaA) Flammable limits in air by volume Auto-ignition temperature Higher Specific Energy (Gross Heating Value) at 15°C Critical temperature Critical pressure
619 5.3 to 14% 595°C 55,550 kJ/kg -82.5°C 4.6 MPaA
199.3
Part 2 Properties of LNG
LNGC DISHA
Cargo Operating Manual Pressure mbar A
Variation in Boiling Point of Methane with Pressure (See Fig 2.1d Density Ratio Methane/Ambient Air Versus Temperature) The boiling point of methane increases with pressure. This variation is shown in the diagram for pure methane over the normal range of pressures on board the vessel. The presence of the heavier components in LNG increases the boiling point of the cargo for a given pressure.
1300
1250
The relationship between the boiling point and the pressure of LNG will approximately follow a line parallel to that shown for 100% methane. 1200
1150 100% Methane
+20 0 - 20
1100
Lighter than air
- 40 Methane vapour temperature
1050
- 60 - 80
1000
-100 -120 Heavier than air
950
-140 -160
900
-162
1.5
1.4
1.3
Ratio =
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
Density of Methane vapour
-161
-160.5
-160
-159.5
-159
-158.5
Temperature
Fig 2.1e Boiling Point of Methane with Pressure
Density of Air
(Density of air assumed to be 1.27 kg/m3 at 15
-161.5
)
Fig 2.1d Density Ratio Methane/Ambient Air Versus Temperature
2-2
Part 2 Properties of LNG
LNGC DISHA
Cargo Operating Manual
Illustration 2.2.2a Flammability of Methane, Oxygen and Nitrogen Mixtures
21
Area EDFE flammable
B E
20
! Caution This diagram assumes complete mixing which, in practice, may not occur.
19 F
18 17 16
Y
15 14 G 13 12 % O x y g e n
M N
Mixtures of air and methane cannot be produced above line BEFC
X D
11 10 9 8 7 6 5 Area HDFC capable of forming flammable mixtures with air, but containing too much methane to explode
4 3 2 1 A 0
10
H 20
30
40
50
60
70
80
Z
90
C 100
Methane % Area ABEDH not capable of forming flammable mixture with air
2-3
Part 2 Properties of LNG
LNGC DISHA 2.2 Characteristics of LNG 2.2.1 Flammability of Methane, Oxygen and Nitrogen Mixtures The ship must be operated in such a way that a flammable mixture of methane and air is avoided at all times. The relationship between gas/air composition and flammability for all possible mixtures of methane, air and nitrogen is shown in the diagram above. The vertical axis A-B represents oxygen-nitrogen mixtures with no methane present, ranging from 0% oxygen (100% nitrogen) at point A, to 21% oxygen (79% nitrogen) at point B. The latter point represents the composition of atmospheric air. The horizontal axis A-C represents methane-nitrogen mixtures with no oxygen present, ranging from 0% methane (100% nitrogen) at point A, to 100% methane (0% nitrogen) at point C. Any single point in the diagram within the triangle ABC represents a mixture of all three components, methane, oxygen and nitrogen, each present in a specific proportion of the total volume. The proportions of the three components represented by a single point can be read off the diagram. For example, at point D: Methane: 6.0% (read on axis A-C) Oxygen: 12.2% (read on axis A-B) Nitrogen: 81.8% (remainder) The diagram consists of three major sectors: 1.
The Flammable Zone Area EDF. Any mixture the composition of which is represented by a point that lies within this area is flammable.
2.
Area HDFC. Any mixture the composition of which is represented by a point that lies within this area is capable of forming a flammable mixture when mixed with air, but contains too much methane to ignite.
3.
Area ABEDH. Any mixture the composition of which is represented by a point that lies within this area is not capable of forming a flammable mixture when mixed with air.
Using the Diagram Assume that point Y on the oxygen-nitrogen axis is joined by a straight line to point Z on the methane-nitrogen axis. If an oxygen-nitrogen mixture of composition Y is mixed with a methane-nitrogen mixture of composition Z, the composition of the resulting mixture will, at all times, be represented by point X, which will move from Y to Z as increasing quantities of mixture Z are added.
Cargo Operating Manual Note ! In this example point X, representing changing composition, passes through the flammable zone EDF, that is, when the methane content of the mixture is between 5.5% at point M, and 9.0% at point N. Applying this to the process of inerting a cargo tank prior to cool down, assume that the tank is initially full of air at point B. Nitrogen is added until the oxygen content is reduced to 13% at point G. The addition of methane will cause the mixture composition to change along the line GDC which, it will be noted, does not pass through the flammable zone, but is tangential to it at point D. If the oxygen content is reduced further, before the addition of methane, to any point between 0% and 13%, that is, between points A and G, the change in composition with the addition of methane will not pass through the flammable zone. Theoretically, therefore, it is only necessary to add nitrogen to air when inerting until the oxygen content is reduced to 13%. However, the oxygen content is reduced to 2% during inerting because, in practice, complete mixing of air and nitrogen may not occur. When a tank full of methane gas is to be inerted with nitrogen prior to aeration, a similar procedure is followed. Assume that nitrogen is added to the tank containing methane at point C until the methane content is reduced to about 14% at point H. As air is added, the mixture composition will change along line HDB, which, as before, is tangential at D to the flammable zone, but does not pass through it. For the same reasons as when inerting from a tank containing air, when inerting a tank full of methane it is necessary to go well below the theoretical figure to a methane content of 1.5% because complete mixing of methane and nitrogen may not occur in practice. The procedures for avoiding flammable mixtures in cargo tanks and piping are summarised as follows: 1.
Tanks and piping containing air are to be inerted with nitrogen or inert gas before admitting methane at ambient temperature until all sampling points indicate 1.0% vol. or less oxygen content.
2.
Tanks and piping containing methane are to be inerted with nitrogen before admitting air until all sampling points indicate 1.0% vol methane.
It should be noted that some portable instruments for measuring methane content are based on oxidising the sample over a heated platinum wire and measuring the increased temperature from this combustion. This type of analyzer will not work with methane-nitrogen mixtures that do not contain oxygen. For this reason, special portable instruments of the infrared type have been developed and supplied to the ship for this purpose.
2-4
Part 2 Properties of LNG
LNGC DISHA 2.2.2 Supplementary Characteristics When spilled on water: 1) Boiling of LNG is rapid, due to the large temperature difference between the product and water. 2) LNG continuously spreads over an indefinitely large area, it results in a magnification of its rate of evaporation until vapourization is complete.
Cargo Operating Manual 5) The heat necessary for the vapourization of LNG comes from the outer environment of the cargo tanks leaking through the cargo tank insulation. As long as the generated vapour is continuously removed by maintaining the pressure as substantially constant, the LNG remains at its boiling temperature.
LNG is a mixture of several components with different physical properties and in particular with different vapourization rate; the more volatile fraction of the cargo vapourizes at a greater rate than the less volatile fraction. The vapour generated by the boiling of the LNG contains a higher concentration of the more volatile fraction than the LNG.
6) If the vapour pressure is reduced by removing more vapour than is generated, the LNG temperature will decrease. In order to make up the equilibrium pressure corresponding to its temperature, the vapourization of LNG is accelerated because of an increased heat leak into the cargo tanks.
The properties of the LNG, i.e. the boiling point, density and heating value, have a tendency to increase during the voyage.
3) No coherent ice layer forms on the water. Reactivity 4) Under particular circumstances, with a methane concentration below 40%, flameless explosions are possible when the LNG strikes the water. It results from an interfacial phenomenon in which LNG becomes locally superheated at a maximum limit until a rapid boiling occurs. However, commercial LNG is far richer in methane than 40% and would require lengthy storage before ageing to that concentration. 5) The flammable cloud of LNG and air may extend for large distances downward (only methane when warmer than -100°C is lighter than air) because of the absence of topographic features which normally promote turbulent mixing. Vapour Clouds 1) If there is no immediate ignition of an LNG spill, a vapour cloud may form. The vapour cloud is long, thin, cigar shaped and, under certain meteorological conditions, may travel a considerable distance before its concentration falls below the lower flammable limit. This concentration is important, for the cloud could ignite and burn, with the flame traveling back towards the originating pool. The cold vapour is denser than air and thus, at least initially, hugs the surface. Weather conditions largely determine the cloud dilution rate, with a thermal inversion greatly lengthening the distance traveled before the cloud becomes nonflammable. 2) The major danger from an LNG vapour cloud occurs when it is ignited. The heat from such a fire is a major problem. A deflagrating (simple burning) is probably fatal to those within the cloud and outside buildings but is not a major threat to those beyond the cloud, although there will be burns from thermal radiations. 3) When loaded in the cargo tanks, the pressure of the vapour phase is maintained as substantially constant, slightly above atmospheric pressure. 4) The external heat passing through the tank insulation generates convection currents within the bulk cargo. Heated LNG rises to the surface and boils.
Methane is a greenhouse gas and as such a pollutant. Cryogenic Temperatures Contact with LNG or with materials chilled to its temperature of about -160°C will damage living tissue. Most metals lose their ductility at these temperatures; LNG may cause the brittle fracture of many materials. In case of LNG spillage on the ship’s deck, the high thermal stresses generated from the restricted possibilities of contraction of the plating will result in the fracture of the steel. The Illustration 1.3.3.a and 2.2.3a shows a typical ship section with the minimum acceptable temperatures of the steel grades selected for the various parts of the structure. Behaviour of LNG in the Cargo Tanks When loaded in the cargo tanks, the pressure of the vapour phase is maintained as substantially constant, slightly above atmospheric pressure. The external heat passing through the tank insulation generates convection currents within the bulk cargo; heated LNG rises to the surface and boils. The heat necessary for the vapourization of LNG comes from the outer environment of the cargo tanks leaking through the cargo tank insulation. As long as the generated vapour is continuously removed by maintaining the pressure as substantially constant, the LNG remains at its boiling temperature. If the vapour pressure is reduced by removing more vapour than generated, the LNG temperature will decrease. In order to make up the equilibrium pressure corresponding to its temperature, the vapourization of LNG is accelerated because of an increased heat leak into the cargo tanks. If the vapour pressure is increased by removing less vapour than is generated, the LNG temperature will increase. In order to reduce the pressure to a level corresponding to the equilibrium with its temperature, the vapourization of LNG is slowed down and the heat transfer from LNG to vapour is reduced.
2-5
Part 2 Properties of LNG
LNGC DISHA
Cargo Operating Manual
2.2.3 Properties of Nitrogen and Inert Gas
Hazards
Nitrogen
Warning Due to the absence or to the very low content of oxygen, nitrogen is an asphyxiant.
Nitrogen is used for the pressurization of the insulation spaces, for purging of cargo pipe lines, fire extinguishing in the vent mast and for the sealing of the gas compressors. It is produced either by the vapourization of liquid nitrogen supplied from shore, or by generators whose principle is based on hollow fiber membranes to separate air into nitrogen and oxygen. Physical Properties of Nitrogen Nitrogen is the most common gas in nature since it represents 79% in volume of the atmospheric air. At room temperature, nitrogen is a colourless and odourless gas. Its density is near that of air, 1.25 kg/m3 under the standard conditions. When liquefied, the temperature is –196°C under atmospheric pressure, density of 810 kg/m3 and a vapourization heat of 199 kJ/kg.
At liquid state, its low temperature will damage living tissue and any spillage of liquid nitrogen on the ship’s deck will result in failure as for LNG. Inert Gas Inert gas is used to reduce the oxygen content in the cargo system, tanks, piping and compressors in order to prevent an air/CH4 mixture prior to aeration post warm up, before refit or repairs and prior to the gassing up operation post refit before cooling down. Inert gas is produced on board using an inert gas generator supplied by SMIT, which produces inert gas at 14,000 Nm3/h with a –45°C dew point burning low sulphur content gas oil. This plant can also produce dry air at 14,000 Nm3/h and –45°C dew point (see section 4.11 for more details). The inert gas composition is as follows: Oxygen:
< 1.0% in vol.
Carbon dioxide:
< 14% in vol.
Carbon monoxide:
< 100 ppm by vol.
Sulphur oxides (SOx):
< 2 ppm by vol.
Nitrogen oxides (NOx):
< 65 ppm by vol.
Nitrogen:
balance
Dew point:
< -45°C
Soot(on Bacharach scale):
0(= complete absence)
Properties of Nitrogen Molecular weight:
28.016
Boiling point at 1 bar absolute (0.1MPaA) :
–196°C
Liquid SG at boiling point:
1.81
Vapour SG at 15°C and 1 bar absolute (0.1MPaA) : 0.97 Gas volume/liquid volume ratio at –196°C :
695
Flammable limits:
Non
Dew point of 100% pure N2 :
Below –80°C
Chemical Properties Nitrogen is considered as an inert gas; it is non flammable and without chemical affinity. However, at high temperatures, it can be combined with other gases and metals.
The inert gas is slightly denser than air: 1.35 kg/m3 abt at 0°C. Warning Due to its low oxygen content, inert gas is an asphyxiant.
2-6
Part 2 Properties of LNG
LNGC DISHA
Cargo Operating Manual
Illustration 2.2.3a Temperature and Steel Grades
Note ! For environmental conditions, refer to section 1.3.3 Deterioration or Failure.
+20.4
LNG On Secondary Barrier
Steel Grade Selection
Grade A Grade E
-22.8
-27.1
-21.5
Insulation Thickness Secondary = 300 mm + Primary = 230 mm 530 mm
Grade A
Grade E
-22.5
-20
Cofferdam Without Heating
Steel Grade Selection
Grade E
Grade A
Grade E
Grade A
Grade E
+5
-15.9
Grade E
Dimensioning case for heating system and full redundancy ie 2 x 100% capacity -19.1
Grade E
Insulation Thickness Secondary = 300 mm + Primary = 230 mm 530 mm
Grade A
Grade E
Grade A
Grade E
Dimensioning case for heating system and full redundancy ie 2 x 100% capacity
-16
-14
Grade D
-60.8
LNG Cargo Temperature = -163℃
Cofferdam With Heating
Cofferdam Without Heating
-64.0
Grade E
Grade A
Grade D
-53 -55
Grade D
Grade D
-5.2
-3 -6.9
0
Grade E
0
LNG Cargo Temperature = -163℃
Cofferdam With Heating
-15.8
-23.3
0
-25.9
-16.9
-20.8
Grade A
Grade E
+5
-19.4
LNG On Secondary Barrier
Grade A
Grade B
-4.0
Grade B
0
Grade B
-1.6
Grade B
-3.3
Grade A
0
Grade B Grade B
-9
Grade B
-1.9
Grade D
Grade A
℃
Air Temperature Inside Compartment
℃
Air Temperature Inside Compartment
℃
Inner Hull Steel Plating Temperature
℃
Inner Hull Steel Plating Temperature
Double Hull & Compartment Temperatures & Steel Grade Selection in way of Tanks No. 2, 3, 4
Grade A
Grade B
Grade D
Double Hull & Compartment Temperatures & Steel Grade Selection in way of Tanks No. 1
2-7
Part 2 Properties of LNG
LNGC DISHA 2.2.4 Avoidance of Cold Shock to Metal Structural steels suffer brittle fracture at low temperatures. Such failures can be catastrophic because, in a brittle steel, little energy is required to propagate a fracture once it has been initiated. Conversely, in a tough material, the energy necessary to propagate a crack will be insufficient to sustain it when it runs into a sufficiently tough material.
Cargo Operating Manual During any type of cargo transfer, and particularly welst loading and discharging, constant patrolling must be conducted on deck to ensure that no leakages have developed. In the event of a spillage or leakage, water spray should be directed at the spillage to disperse and evaporate the liquid and to protect the steelwork. The leak must be stopped, suspending cargo operations if necessary.
Plain carbon structural steels have a brittle to ductile behavior transition which occurs generally in the range of –50°C to +30°C. This, unfortunately, precludes their use as LNG materials (carriage temperature -162°C). The effect is usually monitored by measuring the energy absorbed in breaking a notched bar and a transition curve, as shown in Illustration 2.2.4a, which is typical for plain carbon steels.
In the event of a major leakage or spillage, the cargo operations must be stopped immediately, the general alarm sounded and the emergency deck water spray system put into operation (refer to section 5.4.2).
For this reason, materials which do not show such sharp transition from ductile to brittle fracture as the temperature is lowered, have found obvious application for use in cryogenic situations in general and particularly in liquid methane carriers, for example, invar (36% nickel-iron alloy), austenitic stainless steel, 9% nickel steel and some aluminium alloys such as 5083 alloy. All of these materials behave in a ductile manner at –162°C, so that the chance of an unstable brittle fracture propagating, even if the materials were overloaded, is negligible.
Illustration 2.2.4a Structural Steel Ductile to Brittle Transition Curve
Fracture transition range (mixed fracture appearance)
Brittle fracture
Ductile fracture
In order to avoid brittle fracture occurring, measures must be taken to ensure that LNG and liquid nitrogen do not come into contact with the steel structure of the vessel. In addition, various equipment are provided to deal with any leakages that may occur. The manifold areas are equipped with a stainless steel drip tray, which collects any spillage and drains it overboard. The ship, by way of the manifolds, is provided with a water curtain that is supplied by the deck fire main. The fire main must always be pressurized and the manifold water curtain in operation when undertaking any cargo operation. In addition, fire hoses must be laid out at each liquid dome to deal with any small leakages that may develop at valves and flanges. Permanent drip trays are fitted underneath the items most likely to cause problems and portable drip trays are provided for any other needs.
For a typical mild steel: T1 might be -30; T2 might be +15°C Although this depends on composition, heat treatment etc. the curve can shift to left or right.
Notched bar test Energy absorbed
T1
T2 Temperature
2-8
Part 2 Properties of LNG
LNGC DISHA
Cargo Operating Manual REACTIVITY DATA
2.3 Health Hazards FORMULA U.N. NUMBER FAMILY APPEARANCE ODOUR
CH4 2043 Hydrocarbon Colourless Odourless
METHANE
METHANE “fire damp” “marsh gas” LNG
THE MAIN HAZARD
EMERGENCY PROCEDURES FIRE
Stop gas supply. Extinguish with dry powder, Halon or CO2 . Cool surrounding area with water spray.
LIQUID IN EYE
DO NOT DELAY. Flood eye gently with clean fresh/sea water. Force eye open if necessary. Continue washing for 15 minutes. Obtain medical advice/assistance.
LIQUID ON SKIN
DO NOT DELAY. Treat patient gently. Remove contaminated clothing. Immerse frostbitten area in warm water until thawed. Obtain medical advice/assistance.
VAPOUR INHALED
Remove victim to fresh air. If breathing has stopped, or is weak/irregular, give mouth-to-mouth/nose resuscitation.
SPILLAGE
Stop the flow. Avoid contact with liquid or vapour. Flood with large amounts of water to disperse spill and prevent brittle fracture. Inform Port Authorities of any major spill.
AIR
No reaction.
WATER (Fresh/Salt)
No reaction. Insoluble. May freeze to form ice or hydrates.
OTHER LIQUIDS/ GASES
Dangerous reaction possible with chlorine.
CONDITIONS OF CARRIAGE NORMAL CARRIAGE CONDITIONS
Fully refrigerated.
GAUGING
Closed, indirect.
SHIP TYPE
2G.
VAPOUR DETECTION
Flammable.
MATERIALS OF CONSTRUCTION
PHYSICAL DATA BOILING POINT @ ATMOSPHERIC PRESSURE
-161.5°C
RELATIVE VAPOUR DENSITY
0.554
CRITICAL PRESSURE / CRITICAL TEMPERATURE
4.6 MPag / -82.55°C
MOLECULAR WEIGHT
16.04
SPECIFIC GRAVITY
0.42
ENTHALPY (kcal/kg)
7.0 68.2
COEFFICIENT OF CUBIC EXPANSION
0.0026 per °C @ -165°C
LATENT HEAT OF VAPOURIZATION
UNSUITABLE Mild steel.
Liquid @ -165°C @ -100°C
SUITABLE Stainless steel, aluminium, 9 or 36% nickel steel, copper.
SPECIAL REQUIREMENTS
Vapour 130.2 @ -165°C 140.5 @ -100°C
511 kJ/kg
None
FIRE AND EXPLOSION DATA FLASH POINT -175°C (approx.) FLAMMABLE LIMITS 5.3 -14% AUTO-IGNITION TEMPERATURE 595°C
HEALTH DATA TVL 1000 ppm
ODOUR THRESHOLD Odourless
EFFECT OF LIQUID
Frostbite on skin or eyes. Not absorbed through skin.
EFFECT OF VAPOUR
Asphyxiation - headache, dizziness, drowsiness. Possible low temperature damage to lungs, skin. No chronic effect known.
2-9
Part 2 Properties of LNG
LNGC DISHA
Cargo Operating Manual NITROGEN
FORMULA U.N. NUMBER FAMILY APPEARANCE ODOUR
N2 2040 Noble Gas Colourless Odourless
THE MAIN HAZARD
REACTIVITY DATA EMERGENCY PROCEDURES
FIRE
Non-flammable. Cool area near cargo tanks with water spray in the event of fire near to them.
LIQUID IN EYE
DO NOT DELAY. Flood eye gently with clean sea/fresh water. Force eye open if necessary. Continue washing for 15 minutes. Seek medical advice/assistance.
LIQUID ON SKIN
DO NOT DELAY. Handle patient gently. Remove contaminated clothing. Immerse frostbitten area in warm water until thawed. Obtain medical advice/assistance.
VAPOUR INHALED
Remove victim to fresh air. If breathing has stopped, or is weak/irregular, give mouth-to-mouth/nose resuscitation.
SPILLAGE
Stop the flow. Avoid contact with liquid or vapour. Flood with large amounts of water to disperse spill and prevent brittle fracture. Inform Port Authorities of any major spillage..
-195.8°C
RELATIVE VAPOUR DENSITY
0.967
VAPOUR PRESSURE 2 kg/cm (A)
2 @ -190°C 10 @ -170°C
MOLECULAR WEIGHT
28.01
SPECIFIC GRAVITY
0.9
ENTHALPY (kcal/kg)
Liquid 7.33 @ -196°C 34.7 @ -150°C
COEFFICIENT OF CUBIC EXPANSION
0.005 @ -198°C
LATENT HEAT OF VAPOURIZATION (kcal/kg)
47.5 17.3
No reaction.
WATER (Fresh/Salt)
No reaction. Insoluble.
OTHER LIQUIDS/ GASES
No reactions.
CONDITIONS OF CARRIAGE
PHYSICAL DATA BOILING POINT @ ATMOSPHERIC PRESSURE
AIR
NITROGEN
Vapour 54.7 @ -195°C 52.0 @ -150°C
NORMAL CARRIAGE CONDITIONS
Fully refrigerated.
GAUGING
Closed, indirect.
SHIP TYPE
3G.
VAPOUR DETECTION
Oxygen analyzer required.
MATERIALS OF CONSTRUCTION
@ -196°C @ -150°C
UNSUITABLE
SUITABLE
Mild steel.
Stainless steel, aluminium, 9 or 36% nickel steel, copper.
FIRE AND EXPLOSION DATA FLASH POINT Non-flammable FLAMMABLE LIMITS Non-flammable AUTO-IGNITION TEMPERATURE Non-flammable
SPECIAL REQUIREMENTS HEALTH DATA TVL 1000 ppm
High oxygen concentrations can be caused by condensation and enrichment of the atmosphere in way of equipment at the low
ODOUR THRESHOLD Odourless
temperatures attained in parts of the liquid nitrogen system; materials of construction and ancillary equipment (e.g. insulation) should be resistant to the effects of this. Due consideration should be given to ventilation in areas where condensation might occur to avoid the stratification of oxygen-enriched atmosphere.
EFFECT OF LIQUID
Frostbite on skin or eyes.
EFFECT OF VAPOUR
Asphyxiation. Cold vapour could cause damage.
2 - 10
Part 2 Properties of LNG
Part 3 : Integrated Automation System (IAS) 3.1 General ............................................................................................. 3 - 4 3.2 IAS Overview ................................................................................... 3 - 5 3.3 IAS Function Operation.................................................................... 3 - 7 3.4 IAS Mimics....................................................................................... 3 - 9
Part 3 Integrated Automation System (IAS)
LNGC DISHA
Machinery Operating Manual
Illustration 3.1.1a IAS Overview WHEEL HOUSE
EXT. VDU
CCR INMARSAT-B VIA SHIPS MODEM
ECR COLOR HARD COPIER
COLOR HARD COPIER
ODRM
EXTENSION VDU SYSTEM ALARM PRINTER
CARGO SYSTEM
LOGGING PRINTER
DOSS
DOSS
DOSS
MACHINERY SYSTEM
DOSS
DOSS
DOSS
DOSS
LOGGING PRINTER
ALARM PRINTER
DOSS
EXT. VDU NET (ETHERNET) MACHINERY EXT. VDU SERVER
DOGS
CARGO EXT. VDU SERVER
DOGS
DEO-NET (ETHERNET)
DOPC II
DOPC II
DOHS
PORTABLE EXTENSION VDU 8 SETS 2 SETS
TOTAL 12 RECEPTACLES FOR ACCOMMODATION AREA - CAPT. DAY RM - C/E DAY RM - 2/E DAY RM - 3/E RM - 4/E RM - 5/E RM - E/E RM - C/O DAY RM - 2/O RM - 3/O RM - NWK/O RM - G/E DAY RM
SERIAL I/F FOR CARGO SYSTEM - CUSTODY TRANSFER SYSTEM (DUAL) - LOADING COMPUTER (DUAL) - FLOAT TYPE LEVEL GAUGE SYSTEM - SHIPBOARD MANAGEMENT SYSTEM - GAS DETECTION SYSTEM FOR MACHINERY SYSTEM - SHIPBOARD MANAGEMENT SYSTEM - SHIP PERFORMANCE MONITORING SYSTEM - NO. 1 BOILER (DUAL) - NO. 2 BOILER (DUAL) - MAIN TURBINE (DUAL)
CARGO MIMIC DOHS PANEL
PERSONNEL DOHS ALARM SYSTEM
DOHS PERSONNEL EXTENSION DOHS ALARM SYSTEM DOHS ALARM PANEL
16 PANELS LEGEND DOSS : DEO OPEN SUPERVISORY STATION DOHS : DEO OPEN HISTORY STATION DOPC II : DEO PROCESS CONTROLLER II ODRM : OPEN DCS REMOTE MANAGER DOGS : DEO OPEN GATEWAY STATION
3-1
Part 3 Integrated Automation System
LNGC DISHA
Machinery Operating Manual
Illustration 3.1.1b IAS Overview
WHEEL HOUSE
PORTABLE EXTENSION VDUS
CCR
DOSS
DOSS
DOSS
DOSS
DOSS
DOSS
DOSS
DOSS
DOSS
EXT. VDU NET (ETHERNET)
OPT. CONV. OPT (2 FIBERS)
OPT (2 FIBERS)
DOGS
DOGS
DOHS DEO-NET (ETHERNET)
DOPC II
DOPC II
OPT. CONV.
OPT (2 FIBERS)
(FOR CARGO)
(FOR CARGO)
I/O
I/O
(FOR CARGO)
I/O
DOSS
OPT. CONV.
DOPC II OPT. CONV.
OPT. CONV.
I/O
OPT (2 FIBERS)
ECR
ELECTRIC EQUIPMENT ROOM
DOPC II
OPT. CONV.
I/O
OPT. CONV.
(FOR CARGO)
I/O
I/O
I/O
OPT (2 FIBERS)
OPT (2 FIBERS)
OPT (2 FIBERS)
OPT (2 FIBERS)
SIM
ECR CCR CARGO MIMIC PANEL
OPT (2 FIBERS)
I/O
OPT (2 FIBERS)
I/O
OPT (2 FIBERS)
I/O
OPT (2 FIBERS)
I/O
OPT (2 FIBERS)
I/O
OPT (2 FIBERS)
DOPC II
I/O
DOHS PERSONNEL EXTENSION DOHS ALARM SYSTEM DOHS ALARM PANEL
DOPC II
DOPC II
(FOR MACHINERY)
LEGEND DOSS : DEO OPEN SUPERVISORY STATION DOHS : DEO OPEN HISTORY STATION DOPC II : DEO PROCESS CONTROLLER II ODRM : OPEN DCS REMOTE MANAGER DOGS : DEO OPEN GATEWAY STATION OPT. CONV. : OPTICAL CONVERTOR SIM : SERIAL INTERFACE MODULE
OPT. CONV.
I/O
I/O
DOPC II
(FOR MACHINERY)
I/O
I/O
(FOR MACHINERY)
I/O
I/O
(FOR MACHINERY)
I/O
I/O
PERSONNEL DOHS ALARM SYSTEM
3-2
Part 3 Integrated Automation System
LNGC DISHA
Machinery Operating Manual
Illustration 3.1.1c IAS Overview
W/H
POWER SUPPLY CONCEPT PORTABLE EXTENSION VDUS
CCR
EXT. VDU
ODRM
DOSS4
DOSS3
DOSS2
DOSS1
DOSS
DOSS
DOSS
DOSS
COLOR HARD COPIER
LOGGING PRINTER
ALARM PRINTER
AC220V
CCC
UPS
A
c/o
AC220V (NORMAL) AC220V (EMERG.)
B
UPS1
A
B
C
C D
ECR
ELECTRIC EQUIPMENT ROOM CABINET
E F G
DOHS
H
DOGS
DOSS1
DOSS2
DOSS3
DOSS4
DOSS
DOSS
DOSS
DOSS
DOGS
ALARM PRINTER
I J
UPS
H
F
UPS1
G
UPS2
COLOR HARD COPIER
LOGGING PRINTER
UPS1
D
EQ ROM UPS CABINET
CARGO MIMIC DOHS PANEL
PS
PS
PS
E
ECR CABINET
PS
DOPC II
DOPC II
DOPC II
DOPC II
I/O
I/O
I/O
I/O
I
UPS1
J
UPS2 PS
ECR UPS CABINET
PS
PS
PS
DOPC II
DOPC II
DOPC II
DOPC II
I/O
I/O
I/O
I/O
LEGEND
DOHS PERSONNEL EXTENSION DOHS ALARM SYSTEM DOHS ALARM PANEL
DOSS : DEO OPEN SUPERVISORY STATION DOHS : DEO OPEN HISTORY STATION DOPC II : DEO PROCESS CONTROLLER II ODRM : OPEN DCS REMOTE MANAGER DOGS : DEO OPEN GATEWAY STATION
PERSONNEL DOHS ALARM SYSTEM
3-3
Part 3 Integrated Automation System
LNGC DISHA Part 3 : Integrated Automation System (IAS) 3.1 General The ship’s Integrated Automation System (IAS) has been designed, programmed, and installed by Yamatake Industrial Systems. Two entirely separate systems have been provided within the IAS for cargo/ballast operations (referred to the Cargo System) and machinery/electric generation plant operations (referred to the Machinery System). Other, independent control systems are interfaced either with the Cargo or Machinery Systems. The IAS has been designed to ease and logical for the operator. Most of functions are automatically run, but, at any time, the operator can be intervened.
Machinery Operating Manual An extension VDU network with receptacles for the portable VDU monitor is supplied to monitor the local status at the following locations: -
This system is capable of controlling and monitoring the main propulsion plant and Engine Room auxiliaries, and the electric generating plant system.
Captain’s Day Room Chief Engineer’s Day room 2/E Day Room 3/E Room 4/E Room 5/E Room E/E Room C/O Day Room 2/O Room 3/O Room NWK/O Room Gas/E Room
In addition, the system is capable of controlling and monitoring specified control valves, e.g. superheated steam temp., main turbine lubricating oil, the cooling water, etc. However, auxiliary pump Standby/Auto selection can also be carried out through this system. The following independent systems are interfaced with the Machinery System:
Portable and Extension VDU System The grouping of the alarms allows easy access for identification, action, and alarm handling. As even a momentary interruption of electrical power supply (220V AC) to the IAS could cause the failure of the IAS, a Uninterruptible Power Supply (UPS) system is installed for uninterrupted power supply to the designated IAS operator station.
Extension VDU System The extension VDU system is used in plant monitoring, not in plant operation. The extension VDU also does not require the use of alarms in its operation. There are two kinds of display for plant monitoring as follows. • Alarm summary display: Applies the both the Cargo and Machinery Systems A simplified alarm summary display designed for this system is provided, indicating 100 points of the latest alarms recorded for each of the Cargo and Machinery Systems. • Graphic display: Applies the both the Cargo and Machinery Systems Provides graphic displays designed for these systems. Plant monitoring display only.
B. VDR
Machinery System
This VDU system is only for monitoring, not operations. Both the cargo and machinery can be monitored anywhere, but only 4 users can concurrently connected.
-
Ship Performance Monitoring System No.1 Boiler and Common Part No.2 Boiler Main Turbine Voyage data recorder Shipboard Management System
Common A. Ship Board Management System B. VDR
Cargo System This system is used in the control and monitoring of the cargo and ballast auxiliaries and valves. In addition, automatic sequence control logic programs are provided for the cargo and ballast operations. Displays available include composed of overviews, operational graphics, monitoring graphics, operational guidance graphics and alarm displays. The emergency shutdown system (ESDS), cargo tank protection system (except the cargo tank filling valve close function due to the cargo tank level very high), and machinery trip and safety systems are totally operating independently of the IAS. Alarms for these systems are sent to the IAS. The cargo system signal from the dangerous zone inputs information through Intrinsic Safety barrier(I.S.). The IAS circuit between the dangerous zone and safety zone separate into Highway coupler module to maintain safety circuit condition. The equipment, which is relative to the I.S., supplis the power from I.S. transformer.
Printers Each cargo and machinery system has the following printers in each CCR and ECR. -
Alarm printer Logging printer
1set 1set
The alarm printer prints out alarm history with time information form the ship’s clock. The logging printer provides data logging function by fixed time and operator’s demand. Fixed time logging is initiated by the ship’s time.
Color Hard Copier This color hard copier is used for copying VDU displays. Two sets of Color Hard Copiers are furnished in the CCR and ECR. One is for the Cargo System and the other for the Machinery System.
The following independent systems are interfaced with the cargo system for date gathering, calculation and monitoring purposes: -
Custody Transfer System Loading Computer Float Type Level Gauge System Shipboard Management System Gas Detection System
Common A. Shipboard Management System
3-4
Part 3 Integrated Automation System
LNGC DISHA
Machinery Operating Manual
3.2 IAS Overview Maker
:
The DOSS has two type of keyboard.
Yamatake Industrial System
General As implemented on this ship, the IAS system controls and monitors almost all systems and equipments on board. The functions of the IAS are as follows:
y
Sequence Event
y
Message
Operation keyboard
y
Operator Change
Engineering keyboard
y
System Alarm
y
System Status
The Engineering keyboard is used for the software modification and installation only. The keyboard is furnished on the console with cover. The following figures indicate the layout of keyboard.
Query and retrieve events by various condition. Archive data into backup media. Reliability
System monitoring
Adoption disk mirroring
System operation Alarm handling, summary and acceptance
POWER GOOD FAIL
RESET
H/W Specification
Data logging and trending
STATS
CPU
Data interface to other system
7
8
9
Control of the extension alarm system
4
5
6
AUTO
SP
Operation planning and control
1
2
3
Control of the extension VDU system
.
0
-
Marine-DEO
MAN
!
"
Q
W
E
R
A
S
D
F
$
=
&
*
<
>
?
T
Y
U
G
H
J
I
O
P
K
L
-
CAS
OUT
Prev Page
SIL Next Page
RAM
: 256MB
HDD
: 18GB
DOGS(DEO Open Gateway Station
ENTER
ACK
: Intel Pentium ІІІ 850MHz
Message Clear
Execute
DOGS is a gateway between the DEO-NET and the Extension VDU.
Close Cancel TAB
Marine-DEO is a product name of the IAS(Industrial Automation System), This section describes the following each component specification of Marine-DEO.
DOSS
SP
Z
X
DOHS
: DEO Open History Station : DEO Open Gateway Station
ODRM
: Open DCS Remote Manager
DOPC ІІ
: DEO Process Controller ІІ
V
N
M
M
Prev Disp
Alpha Shift
Next Disp
Layout of Operation Keyboard
DOPC ІІ is a multi-function controller employing control loops, logic functions, sequence control, and I/O processing. - Built-in control / calculation algorithms - Sequence control implemented by CL (Control Language) - Distributed I/O for space saving
DOSS is a human-machine interface of Marine-DEO that runs on Windows 2000 operating system. The DOSS has the following features.
Layout of Engineering Keyboard
It is fully integrated with Marine-DEO and can be a client node for DOPC, DOHS for LNGC monitoring control.
DOHS is a historian and provides histories data for DOSS. Vessel data collection and historian; Collect process data at periodic basis. Collect various events. y
- Peer to peer communication with other DOPC ІІs over the DEO-NET - Memory back-up by flash ROM
Touchscreen in addition to trackball High resolution display (1280 X 1024)
- Remote I/O capability by fiber optic connection using the tag name basis
DOHS(DEO Open History Station)
Operational face plate facility One line alarm indication
ODRM is a facility which realize remote maintenance from land service center via satellite communication. DOPC ІІ(DEO Process Controller ІІ)
DOSS(DEO Supervisory Station)
Display call-up toolbar
Last Cancel
ODRM(Open DCS Remote Manager)
: DEO Open Supervisory Station
DOGS
C
DOPC ІІ consists of ; - DOCM(DOPC Control Module) It is a the main module of the DOPC ІІ consisting of the control modules and the communication interface modules. - Distributed I/O The I/O modules are mounted on DIN rail.
Process Alarm
3-5
Part 3 Integrated Automation System
LNGC DISHA
Machinery Operating Manual
DOCM(DOPC Control Module)
DOSS DOCM Configuration shows the DOCM system. The DOCM is composed of the following modules. Control Module(MSC) Ethernet Module(ETM)
DOHS
DEO-NET A DEO-NET B
X-BUS Module(XBM) Three sets of control module (MSC) have redundant configuration, and execute same processing synchronised each other. The ethernet module (ETM) and the X-BUS module (XBM) compare outputs of three (3) MSCs, and get data by “logic of majority”, i.e., 2 out of 3. Even though one of MSC outputs incorrect data, the remaining two (2) data are correct and used for the control and monitoring.
ETM E-1
E-A
ETM
E-2
E-B
E-3
E-A
E-2
E-B
MSC I-A
E-1
E-3
E-A
MSC I-B
I-1
MSC
I-A
I-2
I-3
E-B
I-B
I-1
XBM
I-A
I-2
I-B
I-3
XBM
DOCM X-BUS A X-BUS B I/O
~
I/O
DOCM Configuration
3-6
Part 3 Integrated Automation System
LNGC DISHA
Machinery Operating Manual
3.3 IAS Function Operation
Data Logging
Time Management The IAS operates with two time data. One is the marine DEO’s standard time, which could be GMT and the other is the ship’s time supplied from the ship’s chronometer. The ship’s time is used for alarm summary displays, alarm printing and report printing. Standard time is applied to trend data and fast alarm printing.
The logging printers of IAS are located as follows. 1) Cargo system – 1 set in CCR 2) Machinery system – 1 set in ECR
Alarm Management The IAS provides some kinds of alarms as follows. 1) Process Alarm Input from ship process by analog and digital signals. Temperature High, Level Low, Pressure High, etc. The alarms are indicated on the Alarm Summary Display within 2 seconds after receiving the signals on analog or digital input modules. Alarm Print out The alarm printers of the IAS are located as follows. 1) Cargo system – 1set in CCR 2) Machinery system – 1set in ECR The historical alarm information are printed out on the alarm printer with reference time. For the process alarm, the alarm printout provides the following events. ---- Alarm occurrence ---- Alarm acknowledgement ---- Alarm recovery The major printout item is as follows.
Example of Alarm Print-out Fast Alarm Function The fast alarm function is a high speed scanning function for finding out a trip cause. The fast alarms are recorded on the hard disk of DOSS automatically. Operator can display and print the recorded the fast alarms. If a equipment comes to trip, the procedure for finding out the trip cause as follows. 1) The representative trip alarm of this equipment is reported on the alarm summary display and the alarm printer. 2) The fast alarms are indicated on the dedicated display and printed on the logging printer with operator’s request. 3) The fast alarms are indicated and printed the order of its occurrence time. Operator can find out the trip cause for that equipment. To realize the Fast Alarm Function, The IAS applies specialized digital I/O modules, i.e. DISOE, Digital Input Sequence of Event. The DISOE provides high-resolution scanning within 20ms.
---- “ALM”, “ACK”, “RTN” ---- DATE/Time : YYYY/MM/DD XX:XX:XX (HH:MM:SS) ---- TAG name ---- Description The “ALM” is printed in red. In addition to the above, the system status changes including system abnormal are printed out on the alarm printer.
Example of Fast Alarm Print-out The available quantity of line of the fast alarm display is as follows. 25 lines/display Max. 2000 lines
3-7
The IAS provides data logging function in accordance with following specification. 1) Fixed time Report This report is printed out automatically in accordance with the selected time interval. (Based on Ship’s Time) 2) Demand Report This report is printed out by the operator’s request. The format of “Demand Report” is same as “Fixed Time Report”. The re-report function is available until next log is activated. Setting of the logging interval, the demand request and the re-reporting request are done from “System Operation Display” Extension Alarm System All alarms detected by the IAS are extended to extension alarm panels located in officer’s / engineer’s cabins and public spaces by the extension alarm system. The alarms are grouped to the extension alarm groups and the group alarm status is annunciated by the extension alarm panels. The alarm annunciation by the extension alarm panels is done by one audible buzzer and annunciation indicators corresponded to extension alarm groups. The extension alarm groups are shown on the following tables. Cargo system y Emergency shutdown y
Gas detection
y
Essential
y
Non essential
y
Cargo IAS abnormal
y Fire Machinery system y Boiler trouble y M/T Trip y M/T Auto power reduction y M/T abnormal y Generator abnormal y Gas detection in E/R y Essential alarm y Non essential alarm y Fire alarm y Personnel alarm y Mach. IAS system abnormal y Bilge
Part 3 Integrated Automation System
LNGC DISHA y
Machinery Operating Manual
E/R call from E/R
KEY
TOOLBAR
ASSOCIATE From Other Graphic Displays
Duty Engineer/Officer Selector Graphic Display
One set of the duty engineer /officer selector by lighting the push button for each cargo and machinery systems are furnished on the CCR and the ECR console as follows. When one of the button is lit, that indicates the UMS mode. For the cargo system:
Process Monitoring Alarm Monitoring Pumps, Valves, Controllers, etc. Manipulating
KEY
TOOLBAR
KEY ASSOCIATE
C/O
2/O
3/O
NWK/O
G/E Graphic Display
For the machinery system C/E
2/E
Trend Display
Pumps, Valves, Controllers, etc. Manipulating
3/E
4/E
5/E
TOOLBAR
ASSOCIATE
Trend Trace Monitoring
E/E SELECT
Personnel Alarm System The following lamps and push buttons are supplied for the personnel alarm system. Start/Stop buttons with buzzer on master panel furnished on ECR console : 1 set - Start/Stop push buttons on engine room entrance : 1 set - Reset push buttons in engine room : 9 sets “System ON” Lamp on W/H extension alarm panel.
: By Keyboard : By Toolbar : By Associated display call-up button : By select a desired alarm point
TOOLBAR
The Personnel Alarm System’s first setting time when activate the system is 27 min. After setting time, the system occur pre-warning to E/R column light. Then can activate the second setting time which is set 3 min. Display Function Assignment The DOSS provides the following major displays. Graphic Display Group Display Trend Display Alarm Summary Display The Graphic Displays take the initiative in operation basically. The function assignment and the relationship among displays are as follows.
4.10 Nitrogen Production System ..........................................................4 - 48 4.11 Inert Gas and Dry Air Generator ....................................................4 - 50 4.12 Fixed Gas Detection System ..........................................................4 - 52 4.13 Cargo & Ballast Valve Control System..........................................4 - 58 4.13.1 Cargo Valve Control System ...............................................4 - 58 4.13.2 Ballast Valve Control System..............................................4 - 60 4.14 Relief Systems ...............................................................................4 - 62 4.14.1 Cargo Tank Relief Valves....................................................4 - 62 4.14.2 Primary and Secondary Insulation Space Relief Valves......4 - 62 4.14.3 Line Relief Valves ...............................................................4 - 62 4.15 Ballast Piping System ....................................................................4 - 64 4.15.1 General Description ............................................................4 - 64 4.15.2 Ballast Water Management (Ballast Exchange) ..................4 - 65 4.16 Loading Computer .........................................................................4 - 70 4.16.1 ON-Line and OFF-Line Mode ............................................4 - 70 4.16.2 Software Configuration.......................................................4 - 70 4.16.3 Explanation of the Ship Manager Screen ............................4 - 71 4.17 Portable Gas Detector ....................................................................4 - 72 4.17.1 Portable Combination Gas Detector....................................4 - 72 4.17.2 Portable Methane Gas Detector ..........................................4 - 73 4.17.3 Portable Oxygen Monitor....................................................4 - 74 4.17.4 Portable CO2 Analyzer .......................................................4 - 75 4.17.5 Dew Point Meter .................................................................4 - 76
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.1a Cargo Piping System
CARGO EQUIPMENT CAPACITY
KEY
1. HIGH DUTY GAS HEATER : 22,600 kg/h
LNG VAPOUR LINE CG514 CG515
FROM IGG IG021 IG020
IG022
CG527
CG526
NO.2 HIGH DUTY COMP. CG510 CG511
CG522
CG512
CG521
FUEL GAS CG405 TO BOILERS
CG517
CG508
NO.2 LOW DUTY COMP. CG502
CS506
SYMBOL
FM
CS505
CG532 FORCING VAPORIZER
CG504
FM
NO.1 LOW DUTY COMP.
CS503
SP502 CG530
CS502
9. DEMISTER : 5,800 kg/h
CG533
CG501
CG503
CS501
8. LOW DUTY GAS COMPRESSOR : 8,000 m3/h
FM
CG518
CS504
7. HIGH DUTY GAS COMPRESSOR : 32,000 m3/h
N2 LINE
CG505
CG507 LOW DUTY GAS HEATER
CG520
6. STRIPPING/SPRAY PUMP : 50 m3/h
IGG LINE
NO.1 HIGH DUTY COMP. CG506
5. CARGO PUMP : 1,650 m3/h
CG509
FM
CG519
FM
4. LNG VAPORIZER : 10,788 kg/h
STRIPPING LINE
CG516
HIGH DUTY GAS HEATER
3. FORCING VAPORIZER : 6,790 kg/h
LNG LIQUID LINE
FM
CG523
CG525
CG002
CG513
SP501 CG524
2. LOW DUTY GAS HEATER : 7,906 kg/h
FM
LNG VAPORIZER
CN683 DEMISTER TO INS.PRESS.
FM
SP601
CG528
DESCRIPTION
SYMBOL
DESCRIPTION
BUTTERFLY VALVE
REMOTE HYD. CONTROL
GLOBE VALVE
AUTOMATIC CONTROL
LIFT CHECK VALVE
MANUAL CONTROL
SWING CHECK VALVE
REDUCER
SAFETY RELIEF VALVE
SPOOL PIECE
STRAINER
CS003 GAS MAIN VAPOUR MAIN CS002
CS004
CS001
STRIPPING/SPRAY MAIN
LIQUID MAIN
SP102
SP401
SP301
CF401
CF301
SP201
SP101 CF101
CF201
CF302
CF402
No.4 CARGO TANK
SP201
CF102
CF202
No.3 CARGO TANK
No.2 CARGO TANK
4-1
No.1 CARGO TANK
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Part 4 Cargo and Ballast System
Cargo Containment System Principle
4.1 Cargo Containment System
The cargo tanks are of a double membrane, Gaz Transport No.96-2 Evolution System design.
General Description
The inner hull, i.e. the outer shell of each of the cargo tanks, is lined internally with the Gaz Transport integrated tank containment and insulation system. This consists of a thin, flexible membrane called the primary membrane, which is in contact with the cargo, a layer of plywood boxes filled with Perlite called the primary insulation, a second flexible membrane similar to the first one called the secondary membrane and a second layer of boxes also filled with perlite in contact with the inner hull called the secondary insulation. The double membrane system meets the requirement of the relevant regulations on the cargo containment system that provides two different ‘barriers’ to prevent cargo leakage.
The Cargo Containment System consists of four double insulated cargo tanks encased within the inner hull and situated in-line from forward to after. The spaces between the inner hull and outer hull are used for the ballast and protect the tanks in an emergency situation such as collision or grounding. The cargo tanks are separated from the other compartments and from each other by five transverse cofferdams that are all dry compartments. The ballast spaces around the cargo tanks are divided into two double bottom wing tanks, port and starboard for each cargo tank. The double bottom tanks extend to the side of the cargo tanks as far up as the trunkways. The LNG to be transported is stored in the four cargo tanks numbered 1 to 4, from fore to after. All cargo tanks have an octagonal transverse section that matches the supporting inner hull. Between the two transverse bulkheads, each tank is composed of a prism placed in a direction parallel to the keel plate. The boundaries of the tanks are as follows:
The tank lining thus consists of two identical layers of membranes and insulation so that in the event of a leak in the primary barrier, the cargo will be contained indefinitely by the secondary barrier. This system ensures that the whole of the cargo hydrostatic loads are transmitted through the membranes and the insulation to the inner hull plating of the ship. The function of the membranes is to prevent leakage, while the insulation supports and transmits the loads and, in addition, minimises heat exchange between the cargo and the inner hull. The secondary membrane, sandwiched between the two layers of insulation, not only provides a safety barrier between the two layers of insulation, but also reduces the convection currents within the insulation.
1) One flat bottom, parallel to the keel plate raised along the ship’s plating by two inclined plates, one on each side.
The primary and secondary insulation spaces are under a pressure controlled nitrogen atmosphere. The primary spaces’ pressure must never exceed the cargo tank pressure to prevent the primary membrane from collapsing inwards. In normal operation, the pressure in the primary and secondary insulation spaces shall be maintained between 0.2 kPag and 0.4 kPag.
2) Two vertical walls each extended at their upper parts by an inclined plate, in order to limit the liquid free surface effect when the tanks are full.
Construction of the Insulation and Barriers
3) One flat top parallel to the trunk bottom.
The primary and secondary barriers are identical and are fabricated from cryogenic invar (a 36% nickel steel, with a very low coefficient of thermal expansion, 0.7 mm thick).
Cargo tank No.1 is slightly different in shape due to its position in the ship. It has a polygonal section and the lengthwise walls are almost parallel to the ship’s plating. Filling Limit for Cargo Tanks Level : The first precaution is to maintain the level of the tanks within the required limits, i.e.: Lower than a level corresponding to 10% of the length of the tank, Or Higher than a level corresponding to normally 70% of the height of the tank.
Thermal expansion coefficient = (1.5±0.5) 10-6mm/°C between 0°C and –180°C (about ten(10) times less than for stainless steel AISI 304 type) Charpy Test at –196°C, > 120 J/cm2 The coefficient of thermal expansion is low enough to enable flat, rather than corrugated sheets to be used. The entire surface area of the membrane is thus in contact with the supporting insulation, so that the load which the system is able to carry is limited only by the load bearing capacity of the insulation. The primary and secondary insulation spaces are made up of boxes fabricated from plywood and filled with expanded perlite. This insulation system allows free circulation of nitrogen and permits gas freeing or inerting to be carried out in the barrier spaces without difficulty. Perlite is obtained from a vitreous rock of volcanic origin which, when heated to a high temperature (above 800°C), is transformed into very small balls. These balls have diameters that measure between a few hundredths to a few tenths of a millimetre. The cellular structure obtained from the process gives the expanded perlite its lightness and thus its excellent insulation properties. The water repellency of the perlite is reduced by a silicon treatment. The insulation is distributed over the hull in two specific areas : 1) The reinforced area located on the upper part of the tank and covering approximately 30% of the total tank height (including the tank ceilings). This area is fitted with reinforced type boxes. 2) The standard area (or non-reinforced area) covering approximately 70% of the tank height (including the tank bottom). This area is fitted with normal boxes (refer to Illustration 1.3.1a). The secondary and primary boxes in the reinforced area are specially built with thicker internal stiffeners to resist the impacts which can be created by the liquid sloshing inside the tanks. The primary reinforced boxes have two 12 mm thick plywood covers stapled on it. The secondary insulation is 300 mm thick whereas the primary insulation is 230 mm thick. (The designed boil-off rate i.e. 0.15% of the total cargo tanks volume per day governs the thickness).
Part 4 Cargo and Ballast System
LNGC DISHA 4.2 Cargo Piping System Description The cargo piping system is illustrated in a simplified drawing (see Illustration 4.1a) showing only the principal features of the system. Liquid cargo is loaded and discharged via the two crossover lines at midship and is delivered to and from each cargo tank liquid dome via the liquid header that runs fore and aft along the trunk deck. Each crossover line at midship separates into two loading/discharging connections, port and starboard, making a total of four loading/discharge connections on each side of the ship. The cargo tank vapour domes are maintained in communication with each other by the vapour header running fore and aft along the trunk deck. The vapour main also has a cross connection at the midship manifold for use in regulating tank pressures when loading and discharging.
Cargo Operating Manual The Inert Gas and Dry-Air System (section 4.11), located in the Engine Room, is used to supply inert gas or dry air to the cargo tanks via piping which connects with the main cargo system through a double, non-return valve to avoid gas returning to the engine room. All of the cargo piping are welded to reduce the possibility of joint leakage. Flanged connections are electrically bonded by means of straps provided between flanges to ensure that differences in potential due to static electricity between the cargo and other deck piping, tanks, valves and other equipment are avoided. Both liquid and vapour systems have been designed in such a way that expansion and contraction are absorbed in the piping configuration. This is done by means of expansion loops and bellows on liquid and vapour piping, respectively. Fixed and sliding pipe supports and guides are provided to ensure that pipe stresses are kept within acceptable limits.
When loading, the vapour header and crossover, together with the HD compressors, are used to return the displaced gas from the tanks back to the shore installation. When discharging, the vapour header is used in conjunction with either the vapour crossover or a vaporizer, to supply gas to the tanks to replace the outgoing liquid cargo.
All sections of liquid piping that can be isolated, and thus possibly trapping liquid between closed valves, are provided with safety valves that relieve excess pressure to the nearest vapour dome. This is a safety measure, although normal working practice is to allow any remaining liquid to warm up and boil off before closing any such valves.
The stripping/spray line can be connected to the liquid crossover lines and can be used to drain or to cool down each cargo tank, and also to spray during discharging if the return vapour is insufficient.
All major valves such as the midship manifold (port and starboard) valves, also called ESD manifold valves, and individual tank loading and discharge valves, are remotely power operated from the IAS, so that all normal cargo operations can be carried out from the Cargo Control Room(CCR).
The vapour header and stripping/spray headers are both connected to the vapour dome of each tank. The vapour domes also house the tank safety valves, pressure pick up and three sample points. The spray line on each tank consists of two spray assemblies inside the tank at the top to distribute the incoming liquid into several spray nozzles to assist in evaporation and thus achieve a better cool down rate. The stripping/spray, liquid and vapour headers have branches to and from the cargo auxiliary’s room with connections to the compressors, heaters and vaporizer for various auxiliary functions. Removable bends are supplied for fitting where necessary to allow cross-connection between the various pipeworks for infrequent uses such as preparing for dry dock and recommissioning after dry dock. The vapour header connects the vapour domes to each other for venting of boil off gas, which discharges to the atmosphere through the vent mast riser No.1. The vapour main also directs the boil-off gas to the engine room for gas burning, via the LD compressors and LD gas heater.
4.2.1 Liquid Line The system comprises a 600\400A butt welded, cryogenic stainless steel pipeline connecting each of the four cargo tanks to the loading/discharge manifolds at the ship’s side by means of a common line. At each tank liquid dome, there is a manifold which connects to the loading and discharge lines from the tank to allow for the loading and discharge of cargo. This manifold on the liquid dome connects to the tank discharge lines from the port and starboard cargo pumps, the loading line, emergency pump well and spray line At certain points along the liquid line, blank flanges and sample points are fitted to facilitate inerting and aeration of system during refit. All sections of the liquid line outside the cargo tanks are insulated with a rigid polyurethane foam, covered with a moulded GRP cover to act as a tough water and vapour tight barrier
4.2.2 Vapour Line The system comprises a 750\600\500\350A cryogenic stainless steel pipeline connecting each of the four cargo tanks by means of a common line to the ship side vapour manifold, the compressor room and the forward vent mast. The line to the cargo compressor room allows the vapour to be used in the following manner:
When an ESD is activated, the manifold valves are closed, discontinuing loading or unloading operations.
Send the vapour to ashore during cargo loading by means of the HD compressors to control pressure in the cargo tanks.
A non-return valve is fitted at each cargo pump delivery valve. A 6 mm hole is drilled in the valve disc to allow the tank discharge lines to drain down and be gas freed. Non-return valves are also fitted at the discharge flange of the compressors. The spray/stripping and emergency cargo pump discharge lines have non-return valves located directly after the hydraulically operated discharge valves.
During ballast/loaded voyages, the boil-off gas is sent to the engine room via the LD compressors and the heater for use as fuel in the boilers.
A small 6 mm diameter spray nozzle is also fitted on top of each cargo pump discharge line inside the tank to cool down the pump tower leg to maintain a cold temperature through the complete discharge. Note ! Electrical bonding by means of straps is provided between bolted flanges. Whenever a section of pipe or piece of equipment is unbolted, the bonding straps MUST be replaced when the flanged joint is re-made.
4-3
During repair periods, the gas must be vapourized and used to purge-dry the cargo tanks. The line to the forward vent mast acts as a safety valve to all tanks and is used to control the tank pressure during normal operations. At certain points along the vapour line, blank flanges and sample points are fitted to facilitate inerting and aeration of system during refit. All sections of the vapour line outside the cargo tanks are insulated with a rigid polyurethane foam covered with a moulded GRP cover to act as a tough water and vapour tight barrier.
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.2.3 Spray Line
4.2.5 Fuel Gas Line
The system comprises a 80/65/40A butt welded, cryogenic stainless steel pipeline connecting the stripping/spray pump in each of the four cargo tanks to the stripping/spray header and serves the following functions by supplying LNG to:
During transportation of LNG at sea, gas vapour is produced due to the transfer of heat from the outside sea and air, through the tank insulation; Energy is also absorbed from the cargo motion due to the vessel’s movement.
Spray rails in each tank, used for tank cool down and gas generation. The main liquid line, used for cooling down lines prior to cargo operations, priming of discharge lines in all cargo tanks to prevent line surge when starting the main cargo pumps.
Under normal power conditions, the boil-off gas is used the fuel in the ship’s boilers. The gas vapour is taken from the vapour header and passed through the mist separator, then on into the LD compressors. It then passes through the LD gas heater before going to the ship’s boilers where it is burnt as fuel.
Supply LNG or LN2 to vaporizers for gas generation to cargo tank and heaters.
4.2.6 Vent Line At certain points along the spray line, blank flanges and sample points are fitted to facilitate inerting and aeration of system during refit. All sections of the spray line outside the cargo tanks are insulated with a rigid polyurethane foam covered with a moulded GRP cover to act as a tough water and vapour tight barrier.
4.2.4 Gas Line (One Tank Operation)
During normal operations the pressure in the tanks is controlled by the use of the boil-off gas in the boilers as fuel, or controlled via the forward vent mast and the common vapour line. Each cargo tank is also fitted with an independent means of venting, comprising of two 250A lines exiting the tank’s top into their own pilot operated relief valve. From here the gas passes through a 300A and/or 450A line into a vent mast where it is vented to the atmosphere.
The system comprises a 300A pipeline that can be connected to the vapour line and the forward vent mast for use when ‘One Tank Operation’ is required.
All vent masts are protected by the N2 purge fire smothering system.
The use of this line enables a single tank to be isolated and repair work to be carried out without having to warm up and inert the whole vessel.
At certain points along the vent line, sample points are fitted to facilitate inerting and aeration of system during refit.
The connection to each individual tank is by means of a spool piece between the 200A blank flanges situated at each vapour dome on the vapour and gas header.
Sections of the vent line outside the cargo tanks are insulated with a rigid polyurethane foam covered with a moulded GRP cover to act as a tough water and vapour tight barrier.
During single tank operations it is possible to connect to the Inert Gas Generator by means of a spool piece.
4.2.7 Inerting/Aeration Line
At certain points along the gas header, blank flanges and sample points are fitted to facilitate inerting and aeration of system during refit.
The system is comprised of a 450 mm flanged line that supplies inert gas/dry air to the cargo tanks and pipelines for inerting and drying during refit periods. The inert gas/dry air is supplied from the inert gas plant situated in the engine room. The line is connected to the vapour header, the gas header and the liquid header by means of a spool piece or isolation valve. By selective use of the spool pieces and flexible hoses, it is possible to inert/aerate all or a single cargo tank.
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Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.3.1a Main Cargo Pump Start Sequence Diagram
UNLOADING SEQUENCE
5
UNLOADING SEQUENCE
ABNORMAL STOP CONDITION
START
SEQ START/STOP SWITCH = "START"
ABNORMAL STOP CONDITION
1
N
WAIT (5SEC)
-SAME AS *A1 MARK -SAME AS *A2 MARK -PUMP STOP
Y OPERATION MODE IS SELECTED Y
N
PER-SET VALUE OF PUMP LOAD TO PUMP LOAD CONTROLLER
SEQ START/STOP SW ITCH STOP
DISCHARGE VALVE POSITION CONTROLLER MODE:CAS Y
OWN CARGO PUMP IS RUNNING N
Y
2
ANOTHER CARGO PUMP START FUNCTION IN SAME TK IS RUNNING N SET PRE-SET VALUE OF CARGO PUMP DISCHARGE VALVE Y POSITION TO CONTROLLER
-CARGO TK FILL V POSITION BAD PV -CARGO TK FILL V POSITION DEV ALARM -CARGO TK FILL V POSITION V FAIL LIST
(MODE:P-AUTO) ANOTHER CARGO PUMP IS SAME TK IS RUNNING
-ESDS -NO.1~4 TK PROTECTION(OR) -SEQUENCE STOP REQUEST -CARGO PUMP AMMERTER BAD PV -CARGO PUMP DISCH VALVE POSITION DEV ALARM -CARGO PUMP DISCH VALVE V FAIL LIST -NO.n TK LEVEL LV
LOAD CONTROLLER MODE:AUTO N *A1
CARGO PUMP START FUNCTION IS COMPLETED
ACTIVATE CHIME (10SEC) N *A2
ANOTHER CARGO PUMP IN SAME TK IS RUNNING
N
Y
N
8 STEP OR 4 STEP
Y FULL OPEN FILLING VALVE
8 STEP
4 STEP
8 STEP OR 4 STEP
4 STEP
8 STEP
FULL CLOSE LIQ ISO VALVE
SEQ START/STOP SWITCH STOP RUN PUMP
5 1
3
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Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
UNLOADING SEQUENCE
ABNORMAL STOP CONDITION
2
UNLOADING SEQUENCE
4
-SAME AS *A1 MARK -SAME AS *A2 MARK -PUMP STOP
DISCHARGE START CONDITION CHECK FILLING V POSITION>=95% AND LIQ ISO V POSITION<=2%
NOT COMPLETED NO
4
COMPLETED Y ANOTHER CARGO PUMP IN SAME TK IS RUNNING
-CARGO TK LIQ ISO V POSITION BAD PV -CARGO TK LIQ ISO V DEV ALARM -CARGO TK LIQ ISO V FAIL LIST
*A3
Y
N ANOTHER CARGO PUMP IN SAME TK IS RUNNING
N
N
Y
8 STEP OR 4 STEP
8 STEP OR 4 STEP
4 STEP
8 STEP
8 STEP OR 4 STEP 8 STEP
4 STEP
8 STEP OR 4 STEP
4 STEP
8 STEP
-FIL V <95% OR ISO.V>2% AND FIL V >2% OR ISO.V<50%
*1 DISCHARGE OPERATION START FULL OPEN
3
-SAME AS *A1 MARK -SAME AS *A2 MARK -PUMP STOP
DISCHARGE START OPE. FINISH CHECK FILLING V POSITION<=2% AND LIQ ISO V POSITION>=50%
Y
8 STEP
ABNORMAL STOP CONDITION
4 STEP
SEQUENCE ABNORMAL STOP PROCESSING
*A4
3
LIQ ISO VALVE FULL CLOSE
TIME (SEC)
-SAME AS *A1 MARK -SAME AS *A2 MARK -SAME AS *A3 MARK
3
FULL OPEN FILL VALVE FULL CLOSE A 10sec
B 40sec
TIME (SEC)
C 60sec
ACTIVATE CHIME(10SEC)
3
*1 THE SET-POINT OF POSITION CONTROLLER IS SET ACCORDING TO THIS DIAGRAM (MODE:P-AUTO)
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Cargo Operating Manual
UNLOADING SEQUENCE
ABNORMAL STOP CONDITION
3
N STRIPPING USE *3 N
-SAME AS *A1 MARK -PUMP STOP -CTS ABNORMAL
Y
STOP LEVEL >= L0*2
STOP *3
TK LEVEL <= L0 *2 + a 1
*4
TK LEVEL<= STOP LEVEL + a 2 Y
Y
STRIPPING INDICATION ON
N
*5
STOP INDICATION ON
-SAME AS *A1 MARK -PUMP STOP
ACTIVATE CHIME(10SEC)
REDUCE PUMP LOAD OF LOAD CONTROLLER AT P-AUTO MODE
*6
WAIT(60 SEC)
STOP PUMP
-SAME AS *A1 MARK
FULL CLOSE DISCHARGE VALVE
N
PUMP STOP Y
STOP AND STRIPPING INDICATION OFF
SEQ START/STOP SWITCH STOP
5 *2 L0:STRIPPING START LEVEL *3 PUMP STOP LEVEL DECIDES WHETHER A PUMP IS "STOP PUMP" OR "STRIPPING PUMP" *4 a1 :STRIPPING LEVEL BIAS *5 a2 :STOP LEVEL BIAS *6 SET POINT:51%
SET PRESET VALUE OF PUMP LOAD TO STRIP PUMP LOAD CONTROLLER
- ESDS - No.1~4 TK PROTECTION - CARGO TK LEVEL <= LOWLOW - CARGO TK LEVEL >=HIGH - CTS ABNORMAL - SEQUENCE STOP REQUEST - DISCHARGE VALVE FAIL LIST - DISCHARGE VALVE DEV ALARM - STRIP PUMP RETURN V/V FAIL LIST - STRIP RETURN VALVE FAIL LIST - STRIP RETURN VALVE DEV ALARM - STRIP PUMP AMMETTER BAD PV - STRIP HEADER PRESS BAD PV - DISCHARGE V POSITON BAD PV - STRIP RETURN V POSITION BAD PV
- SAME AS THE *A1 MARK - PUMP STOP
SET PRESET VALUE OF STRIP HDR PRESS TO STRIP HDR PRESS CONTROLLER
START CONTROL*1
ACTIVATE CHIME(10 SECS)
SEQ START/STOP SWITCH="STOP"
END
*1 DISCHARGE V/V POSITION CONTROLLER MODE : CAS STRIP PUMP LOAD CONTROLLER MODE : AUTO STRIP RETURN V/V POSITION CONTROLLER MODE : CAS STRIP HDR PRESS CONTROLLER MODE : AUTO
1. THIS DRAWING SHOWS ONE(1) CARGO TANK TYPICALLY. THE OTHER CARGO TANKS ARE IDENTICAL. 2. TAG NUMBERS ARE FOR EACH CARGO TANK FROM NO.1 TO NO.4. 3. THE ITEMS MARKED WITH * SHALL BE SUPPLIED BY MAKER CONCERNED. 4. THE FOLLOWING FUNTION SHALL BE PROVIDED: - BLOCKING OF LOW DIFFERENTIAL OR EQUAL PRESSURE TRIP (IAS) - BLOCKING OF THE TANK LEVEL LOW (CTS) - START BLOCKING AT LOW LEVEL - TRIP CAUSE INDICATION (IAS)
B
HS
TO CARGO PUMP TRIP TO CARGO PUMP START & STOP
FROM ESD FROM TPS
CT
STOP
T
OR
CSl
REMARKS :
A
HS 1&2
CSH
CP105 CP106 CP107 CP108
HS
NO.1 CP001.2 CP007.2 CP013.2 CP019.2
* SVB
ZT *
"BRANCH VALVE" CL110 CL210 CL310 CL410
0-1600 Kpa PT
PI
CP101 CP102 CP103 CP104
ZT ZSL *
BC/BC
NO.2 CARGO PUMP
PI
* SVB
CL101 CL201 CL301 CL401
CL102 CL202 CL302 CL402
0-1600 Kpa CP109 CP110 CP111 CP112
ZT *
CL100 CL200 CL300 CL400
CI101 CI201 CI304 CI401
PT
LOCAL
IAS SYSTEM
MAIN PANEL
LOCAL PANEL
ELEC. CABLE
PNEUMATIC
HYDRAULIC
PIPING
"FILLING VALVE"
* SVB
ZT ZSL *
CL105 CL205 CL305 CL405 CI103 CI203 CI303 CI403
NO.1 CARGO PUMP
UA1
UA2
COMMON TRIP
COMMON ALARM
EM'CY PUMP WELL
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Part 4 Cargo and Ballast System
LNGC DISHA 4.3 Cargo Pumps General Description The ship is fitted with submerged, electric, single-stage (the stripping/spray pumps are two-stage), centrifugal cargo pumps manufactured by Shinko Ind. Ltd . They are installed at the bottom of each tank. Two sizes of pump, main cargo and stripping/spray pumps are installed as fixed units, i.e. two main cargo pumps and one stripping/spray pump per tank. In addition, provision is made at each tank to introduce an emergency cargo pump in case of total cargo pump failure. One emergency pump is available on each ship.
Cargo Operating Manual Starting Procedure for the Main Cargo Pumps (See Illustration 4.3.1a) a)
Each cargo pump electric motor is protected from:
c)
Choose the discharge valve symbol for the pump to be started.
The following information appears on the lower side of the screen in the change zone. Valve’s reference % OPEN % CLOSE d) Open the discharge valve 25% (maximum) to prevent cargo pump vibration and pressure surge in the discharge line. If valve position does not correspond to the request, a time-out (valve failed) alarm is display and in this case check electric signal line or hydraulic system. The valve will change to the line process colour. e)
Choose the pump symbol for starting the pump. The following information appears on the right side of the screen (FACE PLATE). Pump’s reference
Overload (over current) Low-current (no load operation)
RUN INPUT
Imbalance between phases (single-phasing) Too long starting Under normal condition, the start method of the cargo pump is soft starting. If soft starting is not available, DOL (Direct On Line) starting can be used with selector switch, soft – direct, on each cargo pump panel of 6.6 kV CSBD. The power supply to the cargo pump motors is made available via cargo switchboards which are arranged in two independent sections that are normally operated as coupled, via bus-tie connection, or independently. The No.1 cargo switchboard supplies the No.1 pumps in all four tanks, while The No.2 cargo switchboard supplies the No.2 cargo pumps. Each the cargo switchboards can be supplied by either, or both, of the main switchboards. Due to high electrical load imposed on the cargo switchboards by the running of main cargo pumps, there is a limitation on the number of pumps that can be run depending on the electrical power management system (start block).
Note ! The starting duration is about 7 seconds for each pump.
b) Select the cargo mimics display.
Operation The cargo pumps are started and stopped from the Cargo Control Room (CCR) mainly via the IAS Schematic display and the associated Group displays. These are also accessed through the loading and unloading plans and monitor Schematic Displays. They will also be automatically stopped in the event of various shut down trips being activated both in relation to the cargo system and the pumps themselves.
Check to confirm that no pumps are in starting phase.
The manifold On-Off valves are controlled from the mimic screen, their status being indicated by the colour code governed by the limit switches.
Starting Procedure for the Stripping/Spray Pumps (See Illustration 4.3.1b) a)
Select the mimic display for the stripping/spray pump’s operation.
b) Choose the pump discharge valve symbol to start the pump. The following information appears on the bottom right hand corner of the screen in the ‘change zone’. Valve’s reference % OPEN % CLOSE c)
Open the discharge valve 25% (maximum) to prevent cargo pump vibration and pressure surge in the discharge line. If valve position does not correspond to the request, a time-out (valve failed) alarm is display and in this case check electric signal line or hydraulic system. The valve will change to the line process colour.
d) Choose the pump symbol for starting the pump. The following information appears on the right side of the screen (FACE PLATE). Pump’s reference
OUTPUT
RUN
STOP INPUT
INPUT
OUTPUT
Valve’s reference
OUTPUT STOP
INPUT OPEN INPUT OUTPUT
INPUT
Valve’s reference
CLOSE OUTPUT
Start the associated main cargo pump. Once the pump has started (the pump symbol changes from ‘White’ stop to run ‘Green’) open the discharge valve gradually from the operator station via the incremental button, to give the required flow-rate.
OUTPUT
OPEN INPUT
OUTPUT CLOSE
INPUT e)
OUTPUT
Start the associated stripping/spray pump.
The discharge pressure and pump motor amps are monitored and finally adjusted to ensure the most efficient operation as indicated in the pump performance graph, with due regard to the liquid head picked up from the cargo pump discharge flange.
The pumps should be started individually and sequentially, as required, with the discharge valve open (approximately 25%).
PUMP Capacity Total Head Suc. Head Liquid Name Temperature Specific Gravity Minimum Flow
Motor : : : : : : :
1,650 m3/h 177 m –m LNG -163 ˚C 0.5 650 m3/h
Output : 560 kW Synchronous Speed :1,800 rpm Electric Source : AC 6,600V 60 Hz
TANK BOTTOM
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Cargo Operating Manual
4.3.1 Main Cargo Pumps
By trimming the vessel 1 meter or more by the stern, it should be possible to reduce the amount of liquid remaining in the tanks to a minimum, if requested.
(See Illustration 4.3.1c) Specification Pump Manufacturer: Pump model: Number of stages: Operating temperature: Capacity rated flow: Total head: Power rated: Efficiency: Rotational speed: Minimum starting level: Minimum restarting level: NPSHR/Pump down level: At rated flow: At minimum flow: Minimum flow: Motor Type: Rated Output Synchronous Speed Electric Power Source Rated Current Starting Current
Shinko Ind. Ltd. SM350 1 -163°C 1,650 m3/h 177 m 497 kW (Motor rated at 560 kW) 80 % 1,800 rpm 1.9 m 0.7 m 1.0 / 0.4 m 0.5 / 0.2 m 650 m3/h Vertical Submerged 3-Phase Induction 560 kW 1800 rpm AC 6600V / 60Hz 68 A 400 A
The cargo pumps may be run in closed circuit on their own tanks by opening the loading valve. This may be required if the discharge is temporarily halted when the tanks are at low level, thereby avoiding the problems of restarting with low level and low discharge pressure. The pump shall be tested before arrival discharge port on calm sea condition, and during loading when the tank level is about 4~5 m subject to terminal’s acceptance. The cargo pumps will be automatically stopped should any of the following occur: 1) Cargo tank pressure below, or equal to, primary insulation space pressure plus 0.5 kPag (ESDS: Cargo Tank Protection). 2) Vapour header pressure below or equal to atmospheric pressure plus 0.3 kPag.
Note ! An insulation test of all pumps is to be carried out after leaving the loading port to establish that all pumps are operational and to allow time for the installation of the emergency cargo pump should it be necessary. Disconnect the earth line of insulation monitor before carrying out this test. Note ! The pump should not be started or operated against closed discharge valve due to potential damage which may result to insufficient cooling and lubrication for motor and bearing and excessive vibration levels associated with zero flow conditions. The restart of pumps in normal operation is restricted depending on the liquid level above the submerged electric motor. Pumps may not be restarted when the tank liquid level is below 700 mm. 1) For tank liquid level 1.9m or more from tank bottom - The motor may be started and stopped by inching continuously twice. The third starting should be carried out after more than 15 minutes have passed after the second stopping. - “Inching” means that the operating time is less than 5 minutes.
3) Extreme high level in cargo tank (99% volume). 4) Activation of emergency shut down trip: (10 push buttons and 12 fusible elements) (ESDS: Stage 1) 5) Activation of ship/shore pneumatic, fibre-optic or electrical shutdown (ESDS: Stage 1).
Each main cargo pump is rated to discharge 1,650 m3/h at 177 m head of LNG. For optimum discharge results, bulk discharge will be carried out with 8 pumps running in parallel.
6) Motor single-phasing.
The pump discharge valves will be throttled to ensure optimum performance indicated by the pump performance graph.
8) High motor current (electrical overload).
2) For tank liquid level less than 1.9m from tank bottom. - The second starting should be carried out after more than 30 minutes have passed after the first stopping. The quantities of cargo remaining in tanks after stripping refer to chapt. 6.6.3 discharging.
7) Low motor current.
9) Low discharge pressure with time delay at starting. During the course of discharge, changes in flow rate and tank levels will alter these readings and the discharge valve will have to be readjusted accordingly. Under normal conditions it should be possible to maintain the full discharge rate until the tank level approaches approximately 1.9 m, at which time the pump will start to cavitate and lose suction as indicated by fluctuations in the discharge pressure and ammeter readings. The discharge valves should be throttled to stabilize conditions and one pump stopped if necessary. The remaining pump should be progressively throttled to maintain suction and prevent the operation of the low discharge pressure trip, until a level of 0.369m.
10) Cargo Control Room stop. 11) Activation of ESDS stage 2. 12) Cargo tank level low. ESDS signifies that all cargo plant is shut down in addition to the pump(s) on the tank(s) in question.
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Cargo Operating Manual
Illustration 4.3.2a Stripping/Spray Pumps
DISCHARGE
Characteristic Curve of Stripping/Spray Pump
1,460 mm ROTOR CORE STATOR CORE
SHAFT
200
H 180
160 140
E
60 40
20 2.0
20
1.5
15
1.0
10
0.5
5
0
Total Head H (m)
STATOR COIL
Height from Inducer Inlet
BALL BEARING
Pump Efficiency E (%)
CABLE
Shaft Horse Power P (kW)
NPSHR Hs (m) Pump Down Hd (m)
TERMINAL BOX
P
Hs
0
0
BALL BEARING
10
BALANCE SEAT
30
40
50
60
Capacity Q (m3/h)
PUMP Capacity Total Head Suc. Head Liquid Name Temperature Specific Gravity Minimum Flow
IMPELLER INDUCER SUCTION STRAINER
SUCTION
20
Hd
Motor : : : : : : :
50 m3/h 160 m –m LNG -163 ˚C 0.5 20 m3/h
Output: 25 kW Synchronous Speed :3,600 rpm Electric Source: AC 440V 60 Hz
TANK BOTTOM
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Cargo Operating Manual
4.3.2 Stripping/Spray Pumps
For the stripping, the stripping/spray pump should be started early enough to avoid possible starting problems due to very low liquid level (about 0.48m).
(See Illustration 4.3.2a) Specification Pump Manufacturer: Pump model: Number of stages: Operating temperature: Capacity rated flow: Total head: Power rated: Efficiency: Rotational speed: Minimum starting level: Minimum Em’cy restarting level: NPSHR/Pump down level: At rated flow: At minimum flow: Minimum flow: Motor Type: Rated Output Synchronous Speed Electric Power Source Rated Current Starting Current
Shinko Ind. Ltd. SM65-2 1 -163°C 50 m3/h 160 m 20.2 kW (Motor rated at 25 kW) 54 % 3600 rpm 1.13 m 0.48 m 0.4 / 0.1 m 0.25 / 0.08 m 20 m3/h Vertical Submerged 3-Phase Induction 25 kW 3600 rpm AC 440V / 60Hz 52 A 300 A
A stripping/spray pump is installed in each cargo tank for cooling and forced vaporization of LNG. It is rated at 50 m3/h at 160 m head of LNG.
The stripping/spray pumps will be stopped automatically should any of the following occur:
2) -
For tank liquid level less than 1.13m from tank bottom. The second starting should be carried out after more than 30 minutes have passed after the first stopping.
Quantities of cargo remaining in tanks after stripping refer to chapt. 6.6.3 discharging.
1) The cargo tank pressure is below or equal to the primary insulation space pressure plus 0.5 kPag (ESDS: Cargo tank protection) 2) The vapour header pressure is below or equal to the atmospheric pressure plus 0.3 kPag (ESDS: Stage 1) 3) Extreme high level in cargo tank (99% volume) 4) Activation of the Emergency Shut Down System trip (10 push-buttons and 12 fusible elements) (ESDS: Stage 1) 5) Activation of ship/shore pneumatic, fibre-optic or electrical shutdown (ESDS: Stage 1) 6) Motor single-phasing 7) Low motor current 8) High motor current (Electrical overload) 9) Low discharge pressure with time delay at starting 10) Cargo Control Room stop 11) Activation of ESDS stage 2
The pumps are started and stopped from the CCR via the IAS. In an emergency all pumps will be stopped by activation of the Emergency Shut Down System trip. The instances when these pumps can be used: 1) Cool down the liquid header prior to discharging. 2) Cool the cargo tank during ballast voyage prior to arrival at the loading terminal by discharging LNG to the spray rails in the tanks. 3) Pump LNG from the tanks to the forcing vaporizer or LNG Vaporizer (emergency case) when forced vaporization of LNG in the boilers is required. 4) Enable each cargo tank to be stripped as dry as possible for reasons such as technical stop involving cargo tank entry.
12) Cargo tank level low low Note ! An insulation resistance test of all pumps is to be carried out after leaving the loading port to establish that all pumps are operational and to allow time for the installation of the emergency cargo pump should it be necessary. The restart of pumps in normal operation are restricted depending on the liquid level above the submerged electric motor. Pumps may not be restarted when the tank liquid level is below 0.48m. 1)
For tank liquid level 1.13m or more from tank bottom - The motor may be started and stopped by inching continuously twice. The third starting should be carried out after more than 15 minutes have passed after the second stopping. - “Inching” means that the operating time is less than 5 minutes.
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Cargo Operating Manual
Illustration 4.3.3a Emergency Cargo Pump
TERMINAL HEADER
Characteristic Curve of Emergency Cargo Pump FLEXIBLE CABLE
LIQUID DOME TOP
WORKING LEVEL
GUIDE ROLLER
29,753.6 mm
TO SWITCH BOARD
220
H
200 180
160 80 60 40
200
20
3.0
150
0
2.0
100
1.0
50
E
140
Total Heal H (m)
POWER CABLE
Pump Efficiency E (%)
JUNCTION BOX
Shaft Horse Power P (kW)
N2 GAS INLET
Height from Inducer Inlet
DISCHARGE
NPSHR Hs (m) Pump Down Hd (m)
COLUME COVER
P SUPPORT WIRE ROPE
POWER CABLE
0
Hs
0
100
200
300
400
500
Hd
600
700
Capacity Q (m3/h) 1,900 mm
EMERG. C. PUMP
PUMP
SUCTION FOOT VALVE
TANK BOTTOM
Capacity Total Head Suc. Head Liquid Name Temperature Specific Gravity Minimum Flow
4 - 15
Motor : : : : : : :
550 m3/h 175 m –m LNG -163 ˚C 0.5 220 m3/h
Output: 220 kW Synchronous Speed :3,600 rpm Electric Source: AC 440V 60 Hz
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.3.3 Emergency Cargo Pump (See Illustration 4.3.3a, see procedure 7.5 for details of installation) Specification Pump Manufacturer: Pump model: Number of stages: Operating temperature: Capacity rated flow: Total head: Power rated: Efficiency: Rotational speed: Minimum starting level: Minimum Emcy restarting level: NPSHR/Pump down level: At rated flow: At minimum flow: Minimum flow: Motor Type: Rated Output Synchronous Speed Electric Power Source Rated Current Starting Current
Electrical connections are made to the fixed junction box which is located adjacent to each pump well. A dedicated starter is available with one circuit breaker which is placed in the No.1 cargo switchboard. This starter supplies all 4 fixed junction boxes.
Shinko Ind. Ltd. SMR200 1 -163°C 550 m3/h 175 m 182 kW (Motor rated at 220kW) 72 % 3600 rpm 1.7 m 0.94 m 1.4 / 0.5 m 0.5 / 0.3 m 220 m3/h
All safety devices are transferred to the emergency pump when the circuit breaker is engaged, as they are the same for the main cargo pumps. Note ! An insulation test of all pumps is to be carried out after leaving the loading port in order to establish that all pumps are operational and to allow time for the installation of the emergency cargo pump should it be necessary. The restart of pumps in normal operation is restricted depending on the liquid level above the submerged electric motor. Pumps may not be restarted when the tank liquid level is below 950 mm. The motor should be started only once as far as possible. If it is necessary to restart unavoidably, restart the motor after more than 15 minutes has passed since motor stops.
Vertical Submerged 3-Phase Induction 220 kW 3600 rpm AC 440V / 60Hz 395 A 3000 A
Each cargo tank is equipped with an emergency pump well or column. This pump well has a foot valve which is held by highly loaded springs in the closed position. Should a failure of either one or both main cargo pumps in one tank require the use of the emergency pump, the emergency pump is lowered into the emergency pump well after the well has been purged with nitrogen. The weight of the emergency pump overcomes the compression of the springs to open the foot valve. A small flow of nitrogen should be maintained as the pump is being installed. (See section 7.5 Emergency Cargo Pump Installation) Note ! Before undertaking this operation it is important to reduce the tank pressure to near to atmospheric pressure and to keep it at this level throughout the entire operation.
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Cargo Operating Manual
Illustration 4.4.1a HD Compressor
PALL 11
PI 1A
PAL 11
PI 2A
TAHH 2A
TAH 2B
TI 2B
PI 8
CUSTOMER
PAL 8
PALL 8A
TAL 8
TAH 8
TI 8
TAHH TAL 9A 9F
TAH 9F
TI 9F
PALL 8C
PAL 8C
TAHH 10A
TAH 10B
A
T
T
VENT
CRYOSTAR
12
11
PLLL 11
T
12 TLHH 2A
A
T
TSHH TSH 2A 2B PSLL 11
PSL 11
TT 2A
PSL 8A PT 8A
TT 2B
PI 11
SEAL GAS
12
A
PSLL 8A
PLLL 8C
T
A
TSL 8
TSHH 9A
TT 8
TT 9A
TE 8
FI 11
TLHH 10A
T
A
TSH 8 PI 8B
TLHH 9A
T
TSL 9F
A
TSH 9F PSLL 8C
TT 9F
PSL 8C
TE 9A
TE 9F
TSHH 10A
TSH 10B
TT 10A
TT 10B
TE 10A
TE 10B
COMMON ALARM
5
L 15.1
EMS 15
EMS 15
EMERGENCY POWER ON EMERGENCY STOP STOP L 15.4
L 15.3
HS 15.1
CA 15
PCV 8
FI 3
FIC 1
HORN
PT 1
PI 2
FIC 1
PT 2
TE 2A
L 15.9
BULKHEAD SEAL
B TI 2
TE 2B
REMOTE START START COMPRESSOR COMPRESSOR
E-MOTOR
TI 8
A
OIL FILTER
ZSL 1
I/P
PDT 1
A
COMPRESSOR RUNNING
PSV 6A OP 6A
Compressor IGV
FE 1
YE 9 DV 1
TE 1
PCV 3C
ZE 3
V 3C
PCV 3B
HIC 3
ZS 3
PI
HS 3
ZI 3
TI 1
ZL 3
4-20mA
PDSH 7A
PDAH 7A
HSL 6
MOTOR ROOM
OIL COOLER
CV 6B
C 6
V 6F
LOCKED OPEN
HS 15.3
TCV 6
RESET EMLH OIL PUMP RUNNING
TI 6A
TI 6B L AUX. L.O. PUMP MOTOR FAIL
F 5B
A 11
TAH 5
TAL 5
YI 9 T
A
YAH 9
YI 9
EMY 6
STEAM INLET
AUX. READY TO L.O. PUMP START AUX. RUNNING L.O. PUMP
DV 5
CRYOSTAR WATER IN
AUX. L.O. PUMP OVERLOAD
WATER OUT
READY TO START AUX. L.O. PUMP
YAHH 9
CLOSEDOPEN REMOTE CONTROL SIGNAL
PDI 7A
CUSTOMER
A
LAL 5
CP 6B
H 5
11
ZLL 3
AUX. L.O. PUMP
EM 6
L/R
12
PDT 7A
COMPRESSOR ROOM
START STOP L.O. PUMP L.O. PUMP
F 5A
A
HY 3 I/P
LOCKED OPEN
HSH 6
TCV 5
DAC 3
DV 6
V 6C
OIL TANK
TI 5A
YSH YT YSHH YLHH 9 9 9 9
PCV 3A
FILL
TSL 5
P
PI
ZLH 1
TSH 5
ZI 3
PDT 7
A
LG 5
ZSL 3
PDI 7B
PDI 7A
CV 6A
V 6B
B
LSL 5
ZT 3
CONTROL SYSTEM TROUBLE
1.5
PSV 6B
F 5C
YET 9
V 6A
PSV 6B
Set : 8 bar
MAIN OIL PUMP
TI 1 TT 1
COMPRESSOR HS CONTROL MOTOR ABNORMAL 15.5 MOTOR ABNORMAL HORN SILENCE
BULKHEAD
F 1
PROCESS GAS IN
ZLL 1
LAMP TEST
F 7
PI 1
ZSH 1
12
HS 15.4
L 15.8
S
FY 1
REMOTE STOP STOP COMPRESSOR COMPRESSOR
CONTROL SYSTEM ABNORMAL
T
PROCESS GAS OUT
READY TO START COMPRESSOR
HSL 15.2
PT 2A
PT 1A
REMOTE
HSH 15.2
SURGE CONTROL PDI 1
EXTERNAL SHUTDOWN
EMERGENCY STOP
L 15.2
DRTD
ZI 3A
READY TO START MOTOR
POWER ON L 15.6
COMPRESSORREADY TO READY TO LOCAL/REMOTE START RUNNING START COMPRESSOR AUX. L.O. PUMP
GEAR BOX F 3
L 15.5
A
L 15.1
A
PT 8
D 5
PCV 11
PLLL 8A
T
A A
INSTRUMENT AIR
TI 10B
COMMON TRIP A
REMOTE START
STEAM OUTLET
4 - 17
REMOTE STOP
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.4 Cargo Compressors
Electric power failure and other trip signal from ESDS.
General Two high duty (HD) compressors, installed in the compressor room on deck, are provided to handle gaseous fluids, LNG vapour and various mixtures of LNG vapour, and inert gas or air during cooling down, cargo operation and tank treatments. Two low duty (LD) compressors, installed in the compressor room on deck, are provided to handle the LNG vapour for the boiler produced by natural boil off and forced vaporization, which is used the fuel. The HD and LD compressors are driven by electric motors, installed in an electric motor room segregated from the compressor room by a gas tight bulkhead; the shaft penetrates the bulkhead with a gas tight shaft seal.
4.4.1 HD Compressors HD Compressors Manufacturer: Model: Type: Volume flow: Inlet pressure: Outlet pressure: Inlet temperature: Shaft speed: Motor speed: Coupling power: Inlet guide vanes setting: HD Compressor Motor Model: Electric Source: Rated Output: Rated Current: Starting Method:
Ventilation flow failure in the electric motor room Safety of the local control system (oil temperature, oil pressure, discharge gas temperature, seal gas pressure and shaft vibration)
IHSW-560LL 6,600 V / 60Hz 950 kW 101 A Soft Start
The compressors are operated locally or from the IAS in the CCR. The following conditions trip the compressors: Safety of the ESDS and tank protection system : Tank No.1, 2, 3 or 4 - differential pressure: tank/primary space ≤ 0.5 kPag Tank No.1, 2, 3 or 4 - differential pressure: tank/primary space = 0 kPag Vapour header pressure ≤ 0.3 kPag Differential pressure: vapour header / primary pressure header = 0 kPag Tank No.1, 2, 3 or 4 - extreme high liquid level (99% volume)
The LO system feeds the following: Journal bearing on both sides of the high-speed shaft Journal bearing on the driven end of the low speed shaft
Compressor Systems
Integral thrust and journal bearing on the non-driven end of low speed Seal Gas System
shaft
The seal gas system is provided to prevent LO mist from entering the process stream (compressed LNG vapour) and to avoid cold gas flow into the gearbox and into the LO system. The seal gas is nitrogen produced by the nitrogen generators on board. The seal gas is injected into the carbon ring with back-up labyrinth type seals between the gearbox shaft bearing and the compressor wheel.
Cryostar CM 400/55 - HD Centrifugal. Single stage. Fixed speed with adjustable guide vanes. 32,000 m3/h 106 kPaA 203 kPaA -140°C 11,200 rpm 3,580 rpm 845.5 kW -30 to +80 deg
A pressure control valve regulates the oil flow to the bearings. Excess oil is bypassed and discharged to the sump. Pump relief valves act as back up and are set at 800 kPag.
The system is maintained by a pressure control valve where seal gas pressure is always higher than the suction pressure (usually adjusted at 30 kPag). Seal gas entering the gearbox from the shaft seals is returned to the LO sump, separated from the oil and vented to atmosphere. After a period of more than 8 days of non-operation, the unit must be purged with dry and warm nitrogen. As long as the seal gas system is operated, the machine can be left in the stand-by mode for extended periods of time.
Sprayers for the gear wheels HD compressors’ bulkhead seals Surge Control System An automatic surge control system is provided to ensure that the compressor flow rate does not fall below the designed minimum during start-up and steady state operation. Below this rate, the gas flow will not be stable and the compressor will be liable to surge, causing shaft vibration that may damage the compressor. All the HD compressors are equipped with an automatic surge control system that consists of: A flow transmitter Suction and discharge pressure transmitter
LO System
A ratio station
LO in the system is stored in a vented 400 liters LO sump. An integrated steam immersion heater with a thermostatic temperature control valve is fitted in the sump to maintain a constant positive temperature and avoid condensation when the compressors are stopped. The heater will automatically switch on at 25°C LO temperature. The auxiliary LO pump dose not operate below 25°C.
An anti-surge controller
LO is supplied from the sump through separate suction strainer screens and one of the two LO pumps. The discharge from the pumps is through check valves to a common LO supply line feeding the gearbox, bearings and bulkhead seal. The main operational pump is driven by the high speed shaft gear. Upon failure of the driven pump, the stand-by electric motor driven auxiliary pump is energized immediately. The stand-by electric motor driven auxiliary pump is also used during start up of the compressors. The LO passes through a fresh water cooled oil cooler and a 3-way temperature control valve, to maintain the LO inlet temperature at approximately 38~47°C. The oil supply to the bearings is fed via a 25 micron duplex filter. The duplex filter has to be switched, as soon as the pressure drop reached 200 kPag differential pressure and the clogged filter cartridge has to be replaced or cleaned.
4 - 18
A surge control valve on the gas stream On the basis of a preset ratio between the gas flow and compressor differential pressure signals, the anti-surge controller produces a signal that modulates a compressor’s surge control valve. Inlet Guide Vanes To achieve the required gas flow, the compressors have inlet guide vanes fitted at the suction end. The vanes are operated by pneumatic actuators which receive control signals from the flow controlled or pressure controlled for vapour head pressure. Selection of control signal is available on the mimic of IAS. The rotation of the vanes is possible through its full range of travel -30° to +80°. The position is indicated both locally and in the IAS (Range 0 to 100%).
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.4.1a HD Compressor
PALL 11
PI 1A
PAL 11
PI 2A
TAHH 2A
TAH 2B
TI 2B
PI 8
CUSTOMER
PAL 8
PALL 8A
TAL 8
TAH 8
TI 8
TAHH TAL 9A 9F
TAH 9F
TI 9F
PALL 8C
PAL 8C
TAHH 10A
TAH 10B
A
T
T
VENT
CRYOSTAR
12
11
PLLL 11
T
12 TLHH 2A
A
T
TSHH TSH 2A 2B PSLL 11
PSL 11
TT 2A
PSL 8A PT 8A
TT 2B
PI 11
SEAL GAS
12
A
PSLL 8A
PLLL 8C
T
A
TSL 8
TSHH 9A
TT 8
TT 9A
TE 8
FI 11
TLHH 10A
T
A
TSH 8 PI 8B
TLHH 9A
T
TSL 9F
A
TSH 9F PSLL 8C
TT 9F
PSL 8C
TE 9A
TE 9F
TSHH 10A
TSH 10B
TT 10A
TT 10B
TE 10A
TE 10B
COMMON ALARM
5
L 15.1
EMS 15
EMS 15
EMERGENCY POWER ON EMERGENCY STOP STOP L 15.4
L 15.3
HS 15.1
CA 15
PCV 8
FI 3
FIC 1
HORN
PT 1
PI 2
FIC 1
PT 2
TE 2A
L 15.9
BULKHEAD SEAL
B TI 2
TE 2B
REMOTE START START COMPRESSOR COMPRESSOR
E-MOTOR
TI 8
A
OIL FILTER
ZSL 1
I/P
PDT 1
A
COMPRESSOR RUNNING
PSV 6A OP 6A
Compressor IGV
FE 1
YE 9 DV 1
TE 1
PCV 3C
ZE 3
V 3C
PCV 3B
HIC 3
ZS 3
PI
HS 3
ZI 3
TI 1
ZL 3
4-20mA
PDSH 7A
PDAH 7A
HSL 6
MOTOR ROOM
OIL COOLER
CV 6B
C 6
V 6F
LOCKED OPEN
HS 15.3
TCV 6
RESET EMLH OIL PUMP RUNNING
TI 6A
TI 6B L AUX. L.O. PUMP MOTOR FAIL
F 5B
A 11
TAH 5
TAL 5
YI 9 T
A
YAH 9
YI 9
EMY 6
STEAM INLET
AUX. READY TO L.O. PUMP START AUX. RUNNING L.O. PUMP
DV 5
CRYOSTAR WATER IN
AUX. L.O. PUMP OVERLOAD
WATER OUT
READY TO START AUX. L.O. PUMP
YAHH 9
CLOSEDOPEN REMOTE CONTROL SIGNAL
PDI 7A
CUSTOMER
A
LAL 5
CP 6B
H 5
11
ZLL 3
AUX. L.O. PUMP
EM 6
L/R
12
PDT 7A
COMPRESSOR ROOM
START STOP L.O. PUMP L.O. PUMP
F 5A
A
HY 3 I/P
LOCKED OPEN
HSH 6
TCV 5
DAC 3
DV 6
V 6C
OIL TANK
TI 5A
YSH YT YSHH YLHH 9 9 9 9
PCV 3A
FILL
TSL 5
P
PI
ZLH 1
TSH 5
ZI 3
PDT 7
A
LG 5
ZSL 3
PDI 7B
PDI 7A
CV 6A
V 6B
B
LSL 5
ZT 3
CONTROL SYSTEM TROUBLE
1.5
PSV 6B
F 5C
YET 9
V 6A
PSV 6B
Set : 8 bar
MAIN OIL PUMP
TI 1 TT 1
COMPRESSOR HS CONTROL MOTOR ABNORMAL 15.5 MOTOR ABNORMAL HORN SILENCE
BULKHEAD
F 1
PROCESS GAS IN
ZLL 1
LAMP TEST
F 7
PI 1
ZSH 1
12
HS 15.4
L 15.8
S
FY 1
REMOTE STOP STOP COMPRESSOR COMPRESSOR
CONTROL SYSTEM ABNORMAL
T
PROCESS GAS OUT
READY TO START COMPRESSOR
HSL 15.2
PT 2A
PT 1A
REMOTE
HSH 15.2
SURGE CONTROL PDI 1
EXTERNAL SHUTDOWN
EMERGENCY STOP
L 15.2
DRTD
ZI 3A
READY TO START MOTOR
POWER ON L 15.6
COMPRESSORREADY TO READY TO LOCAL/REMOTE START RUNNING START COMPRESSOR AUX. L.O. PUMP
GEAR BOX F 3
L 15.5
A
L 15.1
A
PT 8
D 5
PCV 11
PLLL 8A
T
A A
INSTRUMENT AIR
TI 10B
COMMON TRIP A
REMOTE START
STEAM OUTLET
4 - 19
REMOTE STOP
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Operating Procedures
HD Compressor Alarm and Trip Settings No.
To prepare operation of the HD compressors a)
Open the fresh water cooling inlet and outlet for the LO cooler.
b) Open the instrument air supply to the control panel. c)
Check the LO level in the sump tank.
Note ! The sump heater will automatically switch on when the LO temperature falls to 25°C and will switch off at 40°C. The LO temperature should be kept between approximately 40°C to 50°C in normal operations. Do not operate the auxiliary LO pump at temperatures below 25°C.
Tag. No.
Normal Operation Condition
Instrument range Setting Range 0 to 200 kPag
Action
Set Point
Signal
-
-
4 to 20 mA
-
-
4 to 20 mA
H, HH, L, LL
Type
-
1
Suction Gas Pressure
PT 1
6 kPag
2
Discharge Gas Pressure
PT 2
103 kPag
3
Suction Gas Temperature
TT 1
-140 °C
-200 to +200°C
-
-
-
4 to 20 mA
TT 2A
-110 °C
-200 to +200°C
-
-
-
4 to 20 mA
4
d) Start the LO heater about 30 minutes (depending on the ambient temperature) prior to the expected compressor start-up.
Item
Discharge Gas Temperature TE2A
5
Discharge Gas Temperature TE2B
6
IGV Start Position
-2.5 to 20 kPag 0 to 200 kPag 0 to 110 kPag
TSHH 2A
-
-
HH
T
+100°C
Contant
TT 2B
-110 °C
-200 to +200°C
-
-
-
4 to 20 mA
TSH 2B
-
-
H
A
+90°C
Contant
ZSL 3
-
-
-
I2
-
Contact
ZSH 1
-
-
-
I2
-
ZSL 1
-
-
-
-
-
-
-
-
4 to 20 mA 4 to 20 mA
7
Surge Valve Position
8
Process Gas Flow
PDT 1
5.5 kPag
YET 9
5 to 20 µm
0 to 100 µm
-
-
-
9
Vibration YE9
YSH 9
-
-
H
A
40 µm
Contact
YSHH 9
-
-
HH
T
45 µm
Contact
PDT 7
50 kPag
-
-
-
4 to 20 mA
0 to 62 kPag 0 to +5.5 kPag
0 to 2100 kPag
Contact
e)
Open the seal gas supply manual valve.
10
Oil Filter Diff. Press.
PDSH 7A
-
-
H
A
250 kPag
contant
f)
Open the compressor suction and discharge valves.
11
Oil Tank Level
LSL 5
-
-
L
A, I1
-
Contact
12
Oil Heater Temperature
TCV 5
g) Run the auxiliary LO pump to warm up the gearbox and bearings for about 15 -30 minutes prior to the compressor start-up. Check the LO system for leaks.
13
Temperature Oil Tank
14
Temperature Oil System(TE8)
h) Ensure that the IGV position is set at 0% (start position). i)
Press the compressor reset button and check that all alarms/trip lamps are off and the if ready to start lamp is on.
15 Temperature Oil Bulkhead(TE10B) Bearing Temperature (TE9A)
Switch on power to the control cabinet.
k) At least two alternators should be coupled to the main switchboard to have sufficient power available at the cargo switchboards. l)
TSH 5
Temperature Oil Bulkhead(TE10A)
16
j)
TSL 5
When stopping the compressor, leave the auxiliary LO pump running and seal gas pressure on until the compressor is warm (approximately 1 hour).
! Caution A maximum of 2 consecutive starts is allowed. 180 minutes must be allowed for cool down of the soft start compensation transformer before a further start attempt. T : Trip, A : Alarm I1 : Start-up interlock L.O pump I2 : Start-up interlock machine
17
Bearing Temperature TE9F
0 to 500 kPag
40°C 55°C
-45 +93°C
-
-
-
L
A, I1
25°C
Contact
H
A
60°C
Contact
TT 8
~ 42°C
0 to +100°C
-
-
-
4 to 20 mA
TSL 8
-
-
L
I2
20°C
Contact
TSH 8
-
-
H
A
55°C
Contact
TT 10A
~ 60°C
0 to +100°C
-
-
-
4 to 20 mA
TSHH 10A
-
-
HH
T
+80°C
Contant
TT 10B
~ 60°C
0 to +100°C
-
-
-
4 to 20 mA
TSH10B
-
-
H
A
75°C
Contant
TT 9A
~ 65 °C
0 to +100°C
-
-
-
4 to 20 mA
TSHH 9A
-
-
HH
T
75°C
Contant
TT9F
~ 65 °C
-
-
-
L
A, I2
15°C
4 to 20mA Contant
H
A
70°C
Contant
-
-
-
4 to 20 mA
TSL 9F
-
0 to +100°C -
TSH 9F
-
-
PT 8
~ 160 kPag
0 to 1000 kPag
18
Lub. Oil Pressure (Gear Box)
-
L
A, I2
100 kPag
Contant
Lub. Oil Pressure (Gear Box)
PSL 8A PSLL 8A
-
19
~ 160 kPag
-100 to 125 kPag
LL
T
80 kPag
Contact
20
Lub. Oil Pressure (Bulkhead)
PSL 8C
~ 110 kPag
-100 to 125 kPag
L
A, I2
40 kPag
Contact
21
Lub. Oil Pressure (Bulkhead)
PSLL8C
~ 110 kPag
-100 to 125 kPag
LL
T
20 kPag
Contact
22
Seal Gas Control Valve
PCV11
23
Seal Gas Pressure
PSL11
-
-100 to 125 kPag
L
A, I1, I2
20 kPag
Contact
24
Seal Gas Pressure
PSLL11
-
-100 to 125 kPag
LL
T
15 kPag
Contact
25
IGV Position ZE3
ZT3
-
-30 to +80 °
-
-
-
4 to 20 mA
26
IP Converter Control Valve
PCV 3A
200 kPag
27
HIC Control Valve
PCV 3B
100 kPag
28
Nozzle Actuator Control Valve
PCV 3C
600 kPag
4 - 20
0 to 500 kPag
25 kPag
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.4.2a LD Compressor PALL 11
PI 1A
PAL 11
PI 2A
TAHH 2A
TAH 2B
TI 2B
PI 8
CUSTOMER
PAL 8
PALL 8A
TAL 8
TAH 8
TI 8
TAHH TAL 9A 9F
TAH 9F
TI 9F
PALL 8C
PAL 8C
TAHH 10A
TAH 10B
COMMON TRIP A
A
T
T
VENT
CRYOSTAR
12
11
PLLL 11
T
12 TLHH 2A
A
T
TSHH TSH 2A 2B PSLL 11
PSL 11
TT 2A
PSL 8A PT 8A
TT 2B
PI 11
SEAL GAS
12
A
PSLL 8A
PLLL 8C
T
A
TSL 8
TSHH 9A
TSL 9F
TT 9A
TT 9F
TT 8
TE 8
FI 11
TLHH 10A
T
A
TSH 8 PI 8B
TLHH 9A
T
A
TSH 9F PSLL 8C
PSL 8C
TE 9A
TE 9F
TSHH 10A
TSH 10B
TT 10A
TT 10B
TE 10A
TE 10B
COMMON ALARM
5
L 15.1
EMS 15
EMS 15
EMERGENCY POWER ON EMERGENCY STOP STOP L 15.4
L 15.3
HS 15.1
CA 15
PCV 8
FI 3
FIC 1
HORN
PT 1
PI 2
FIC 1
PT 2
TE 2A
L 15.9
BULKHEAD SEAL
B TI 2
TE 2B
REMOTE START START COMPRESSOR COMPRESSOR
E-MOTOR
TI 8
A
OIL FILTER
ZSL 1
I/P
PDT 1
A
COMPRESSOR RUNNING
PSV 6A OP 6A
Compressor IGV
FE 1
YE 9 DV 1
TE 1
PCV 3C
ZE 3
V 3C
ZI 3
PCV 3B
HIC 3
ZS 3
PI
TI 5A
HS 3
ZI 3
TI 1
ZL 3
4-20mA
PDSH 7A
PDAH 7A
HSL 6
MOTOR ROOM
OIL COOLER
CV 6B
C 6
V 6F
LOCKED OPEN
HS 15.3
TCV 6
RESET EMLH OIL PUMP RUNNING
TI 6A
TI 6B L AUX. L.O. PUMP MOTOR FAIL
F 5B
A 11
TAH 5
TAL 5
YI 9 T
A
YAH 9
YI 9
EMY 6
STEAM INLET
AUX. READY TO L.O. PUMP START AUX. RUNNING L.O. PUMP
DV 5
CRYOSTAR WATER IN
AUX. L.O. PUMP OVERLOAD
WATER OUT
READY TO START AUX. L.O. PUMP
YAHH 9
CLOSEDOPEN REMOTE CONTROL SIGNAL
PDI 7A
CUSTOMER
A
LAL 5
CP 6B
H 5
11
ZLL 3
AUX. L.O. PUMP
EM 6
L/R
12
PDT 7A
COMPRESSOR ROOM
START STOP L.O. PUMP L.O. PUMP
F 5A
A
HY 3 I/P
LOCKED OPEN
HSH 6
TCV 5
DAC 3
DV 6
V 6C
OIL TANK
YSH YT YSHH YLHH 9 9 9 9
PCV 3A
FILL
TSL 5
P
PI
ZLH 1
TSH 5
PDT 7
A
LG 5
ZSL 3
PDI 7B
PDI 7A
CV 6A
V 6B
B
LSL 5
ZT 3
CONTROL SYSTEM TROUBLE
1.5
PSV 6B
F 5C
YET 9
V 6A
PSV 6B
Set : 8 bar
MAIN OIL PUMP
TI 1 TT 1
COMPRESSOR HS CONTROL MOTOR ABNORMAL 15.5 MOTOR ABNORMAL HORN SILENCE
BULKHEAD
F 1
PROCESS GAS IN
ZLL 1
LAMP TEST
F 7
PI 1
ZSH 1
12
HS 15.4
L 15.8
S
FY 1
REMOTE STOP STOP COMPRESSOR COMPRESSOR
CONTROL SYSTEM ABNORMAL
T
PROCESS GAS OUT
READY TO START COMPRESSOR
HSL 15.2
PT 2A
PT 1A
REMOTE
HSH 15.2
SURGE CONTROL PDI 1
EXTERNAL SHUTDOWN
EMERGENCY STOP
L 15.2
DRTD
ZI 3A
READY TO START MOTOR
POWER ON L 15.6
COMPRESSORREADY TO READY TO LOCAL/REMOTE START RUNNING START COMPRESSOR AUX. L.O. PUMP
Cryostar CM 300/45-LD Centrifugal. Single stage. Variable speed with adjustable guide vanes. 8,000 m3/h 106 kPaA 196 kPaA -42°C 23,400 rpm 214.4 kW -30 to +80 deg
The compressors are operated locally or from the IAS in the CCR. The following conditions trip the compressors; Safeties in ESDS and Tank Protection System; Tank No.1, 2, 3 or 4 - differential pressure: tank/primary space ≤ 0.5 kPag Tank No.1, 2, 3 or 4 - differential pressure: tank/primary space = 0 kPag Differential pressure: vapour header/atmospheric pressure ≤ 0.3 kPag Differential pressure: vapour header/primary pressure header = 0 kPag Electric power failure and other trip signal from ESDS. Safeties in combustion control system of the boilers.
LO System LO in the system is stored in a vented 400 liters LO sump. An integrated steam immersion heater with a thermostatic temperature control valve is fitted in the sump to maintain a constant positive temperature and avoid condensation when the compressors are stopped. LO is supplied from the sump through separate suction strainer screens and one of the two LO pumps. The discharge from the pumps is through check valves to a common LO supply line feeding the gearbox, bearings and bulkhead seal. The main operational pump is driven by the high speed shaft gear. Upon failure of the driven pump, the stand-by electric motor driven auxiliary pump is energized immediately. The stand-by electric motor driven auxiliary pump is also used to start the compressors. The LO passes through a sea water cooled oil cooler and a 3-way thermal bypass temperature control valve, to maintain the LO inlet temperature at approximately 35°C. The oil supply to the bearings is fed via a 25 micron duplex filter with an automatic continuous flow switch over valve. A pressure control valve regulates the oil flow to the bearings. Excess oil is bypassed and discharged to the sump. Pump relief valves act as back up and are set at 800 kPag.
Inlet Guide Vanes and Motor Speed Control To achieve the required gas flow, the compressors have inlet guide vanes fitted at the suction end. The vanes are operated by pneumatic actuators which receive control signals of the fuel gas demand from the boilers. The rotation of the vanes is possible through its full range of travel -30° to +80°. The position is indicated both locally and in the IAS (Range 0 to 100%). Speed of electric motor is controlled with the range from 50% speed to 100% speed via invertor panel Bulkhead Shaft Seals Each compressor shaft is equipped with a forced lubricated bulkhead shaft seal preventing any combustible gas from entering the electric motors room. The seals are flexibox supply. They are fixed on the bulkhead and float on the shafts, supported by two ball bearings.
The LO system feeds the following: Journal bearing on both sides of the high speed shaft Journal bearing on the driven end of the low speed shaft
Safeties on local control system (oil temperature, oil pressure, discharge gas
Integral thrust and journal bearing on the non-driven end of the low speed shaft
temperature, seal gas pressure and shaft vibration)
Sprayers for the gear wheels
Compressor Sub Systems
On the basis of a preset ratio between the gas flow and compressor differential pressure signals, the anti-surge controller produces a signal which modulates a surge control valve.
The LO seal ensures tightness between the two bearings. The lubrication comes from the main LO circuit. Operating Procedures To prepare the LD compressors for running: a)
Open the cooling water inlet and outlet LO cooler (usually left open). b) Open the instrument air supply to the control panel.
LD compressors’ bulkhead seals
Seal Gas System The seal gas system is provided to prevent LO mist from entering the process stream (compressed LNG vapour) and to avoid cold gas flow into the gearbox and into the LO system. The seal gas is nitrogen produced by the nitrogen generators on board.
Surge Control System An automatic surge control system is provided to ensure that the compressor flow rate does not fall below the designed minimum. Below this rate, the gas flow will not be stable and the compressor will be liable to surge, causing shaft vibration that may result in damage to the compressor.
The seal gas is injected into the carbon ring with back-up labyrinth type seals between the gearbox shaft bearing and the compressor wheel.
All the LD compressors are equipped with an automatic surge control system which consists of: A flow transmitter
The system is maintained by a pressure control valve where the seal gas pressure is always higher than the suction pressure (usually adjusted at 30 kPag).
A compressor differential pressure transmitter
The seal gas entering the gearbox from the shaft seals is returned to the LO sump, separated from the oil and vented to the atmosphere.
An anti-surge controller
c)
d) Start the LO heater about 30 minutes (depending on ambient temperature) prior to the expected compressor start up. Note ! The temperature in the LO Sump Tank is controlled by TCV5. The LO temperature should be kept between 40°C to 50°C in normal operations. Do not operate the auxiliary LO pump at temperature below 25°C. e) Open the seal gas supply manual valve. f)
A ratio station
A surge control valve on the gas stream
4 - 22
Check the LO level in the sump tank.
Open the compressor suction and discharge valves.
g) Run the auxiliary LO pump to warm up the gearbox and bearings for about 15 -30 minutes prior to the compressor start-up. Check the LO system for leaks.
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
h) Switch on power to the control cabinet. i)
LD Compressor Alarm and Trip Settings
Switch on the power to the variable speed controller. (Each LD compressor is supplied from a separate cargo switchboard i.e. Port and Starboard).
On the IAS in the CCR; a)
Set up the cargo piping system to carry out the correct operation.
b) Select the appropriate mimic on the LD compressor for the correct operation.
No.
Item
Tag. No.
Normal Operation Condition
1
Suction Gas Pressure
PT 1
6 kPag
2
Discharge Gas Pressure
PT 2
96 kPag
3
Suction Gas Temperature
4
Discharge Gas Temperature TE2A
5
Discharge Gas Temperature TE2B
6
IGV Start Position
Instrument range Setting Range 0 to 200 kPag
-2.5 to 20 kPag 0 to 200 kPag 0 to 110 kPag
Action
Set Point
Signal
-
-
4 to 20 mA
-
-
-
4 to 20 mA
H, HH, L, LL
Type
-
TT 1
-42 °C
-200 to +200°C
-
-
-
4 to 20 mA
TT 2A
3.5 °C
-200 to +200°C
-
-
-
4 to 20 mA
TSHH 2A
-
-
HH
T
+100°C
Contant
TT 2B
3.5 °C
-200 to +200°C
-
-
-
4 to 20 mA
TSH 2B
-
-
H
A
+90°C
Contant
ZSL 3
-
-
-
I2
-
Contact
ZSH 1
-
-
-
I2
-
ZSL 1
-
-
-
-
-
-
-
-
4 to 20 mA 4 to 20 mA
7
Surge Valve Position
8
Process Gas Flow
PDT 1
4 kPag
d) The message ‘Ready to start’ appears on the mimic display below the compressors when safety is clear.
YET 9
5 to 20 µm
0 to 100 µm
-
-
-
9
Vibration YE9
YSH 9
-
-
H
A
40 µm
Contact
YSHH 9
-
-
HH
T
45 µm
Contact
e)
Start the compressor motor.
10
Oil Filter Diff. Press.
PDT 7
50 kPag
-
-
-
4 to 20 mA
PDSH 7A
-
-
H
A
250 kPag
contant
f)
Switch the compressor control to automatic mode.
11
Oil Tank Level
LSL 5
-
-
L
A, I1
-
Contact
12
Oil Heater Temperature
TCV 5
c)
The IGV (inlet guide vanes) must be set at 0% and motor speed adjusted to 50% before starting the compressor.
TSL 5
13
Temperature Oil Tank
14
Temperature Oil System(TE8)
TSH 5
Temperature Oil Bulkhead(TE10A) 15 Temperature Oil Bulkhead(TE10B)
T : Trip, A : Alarm I1 : Start-up interlock L.O pump I2 : Start-up interlock machine
Seal Gas Press. Low Low Aux. L.O.P Ready to start (To starter)
AND
Seal Gas Press. Low
FUNCTION IN MAIN CONTROL PANEL (M.C.P) 2
Surge valve open ZSH1
Oil tank temp. Low
11
Aux. L.O.P Motor Overload
IGV in start position ZSL3
Aux. L.O.P Start Ready
Common trip
8
Common Alarm
7
1
Ready to start LOP Feedback Aux. L.O.P Running
Aux.L.O.P Ready to start (To M.C.P)
AND
2
OUTPUT
AND
Compressor Ready to start (To Starter)
AND
Compressor Ready to start (To M.C.P)
Cont. System Trouble
Remote/Local in Local Pos
Compressor Start Ready
L.O.P Local Start Aux.L.O.P Start Ready
1
Aux.L.O.P Start order (To start)
AND
Ready to Start L.O.P Main Motor running
5
Feedback Compressor running
4
6 11
Remote/Local in Remote Pos
Aux.L.O.P Start Ready
1
AND
3
Main Motor running
4
Main Motor running
4
AND
Compressor Start ready
impuls 1-0
AND
5
Compressor Ready to start
R
9
Aux.L.O.P Stop order
OR
S
Main Motor Start order (To Starter)
Remote/Local in Remote Pos. M.Motor Remote Start
Remote/Local in Local Pos.
Compressor Start ready
OR
L.O.P Local Stop
AND
5
4
Compressor Ready to start
Remote/ Local in Remote Pos. L.O.P Remote Stop
OR 4
AND 3
0____21
4
0____20
t=21sec
Main Motor running
Compressor running (To M.C.P)
=
M.Motor Local Start
L.O.P run other blackout
Gear Oil Press.Low
6
Remote/Local in Local Pos.
Gear Oil Press.Low
Main Motor running
Electrical failure Comp.contactor line (To M.C.P)
AND
6
Feedback Comp. running
S
4
Main Motor running
t= 30 sec
Feedback Comp. running
OR
Ready to Start L.O.P
Main Motor runing
0____30
Main Motor Start order
L.O.P Remote Start
9
R
Compressor Stop order
Aux.L.O.P Stop order (normal operation=1) (to starter)
Remote/Local in Local Pos.
OR
Main Motor Local Stop
AND
Remote/Local in Remote Pos.
OR
Main Motor Remote Stop
t=20sec
AND
0____120
Emergency stop
Main Motor Stop order (normal operation=1) (To Starter)
t=120sec
Aux. L.O.P Motor overload
Common trip
Electrical failure L.O.P
Electrical failure Main Motor
0____10
Aux.L.O.P Start order Feedback Aux. L.O.P Running
2
AND
Electrical faiure L.O.P contactor line (To. M.C.P)
Feedback Aux. L.O.P Running
2
=
Aux. L.O.P running (To.M.C.P)
t=10sec
8
4 - 24
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.5a H/D & L/D Gas Heater
PIT 2 P1 3
TE 2
GAS OUTLET
TSHH 2
CG520 CG525
(WARM UP)
VENT GAS OUTLET
CG521 CG526
CD313 CD317
SC356
STEAM INLET
(FUEL GAS)
P1 1
LS 4B
HY 2
ZS 2
HS 2
LS 4A
HIC 2
TSLL 4
TE 4
LI 4 CD312 CD316
CD310 CD311 CONDENSATE DRAIN
D SV 2 CG517 CG522 GAS INLET
SC310 SC314 D
TCV 2 CG519 CG524
S
CG518 CG523
H
DRAIN
TCV 1
KEY LNG VAPOUR STEAM
S SV 1
ZS 1 HS 1 HIC 1
PCV 6
PI 6
INSTRUMENT AIR SUPPLY
HY 1
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Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.5 H/D & L/D Gas Heater General Description There are two steam-heated HD & LD gas heaters located in the cargo compressor room, which is situated on the starboard after side of the trunk deck.
Operating Procedure in Warming-up configuration The vapour lines will be set for using the HD compressor to deliver vapour to the HD gas heater. The LD gas heater can be used for this operation by opening the cross connection valve CG529 at emergency case. a) Open the shell side vent valve. b) Open the shell side condensate valves and check the drains.
The heaters are shell and tube type.
c)
The heaters are used for the following functions: H/D Gas Heater Heating the LNG vapour is delivered by either of the HD compressors at the specified temperature for warming up the cargo tanks before gas freeing.
d) When all the air has been expelled from the shell, shut the vent valve.
Heating inert gas is supplied from inert gas generator for inerting operation and warming up with inert gas.
g) Set the LNG vapour lines as detailed for the operation and put the heater in use.
L/D Gas Heater Heating boil-off gas is delivered by either of the LD compressors for fuel gas to the boiler or for venting to atmosphere via the liquid header or via the gas main. free flow can be applied alternatively.
h) In the CCR, set the controls for the heater to the ON position on the IAS.
! Caution When returning heated vapour to the cargo tanks, the temperature at the heater outlet should not exceed +85°C, to avoid possible damage to the cargo piping insulation and safety valves. Specification: High Duty Gas Heater : Manufacturer: Model: Type: Rated Capacity: Vapour Inlet Temperature: Vapour Max Outlet Temperature: Vapour Inlet Pressure: Pressure Drop(Calculated): Heating Capacity: Steam Consumption: Steam Inlet/Outlet Temperature: Low Duty Gas Heater : Manufacturer: Model: Type: Rated capacity: Vapour inlet temperature: Vapour max outlet temperature: Vapour Inlet Pressure: Pressure Drop(Calculated): Heating Capacity: Steam Consumption: Steam Inlet/Outlet Temperature:
e)
When water has been drained from the shell, shut the drain valve.
f)
Slowly open up the steam inlet valve.
i)
Open the instrument air supply to the controls for the heater.
j)
Check the condensate level in the sight glass.
k) Set the temperature and level controller to the correct settings for the operation being undertaken (first stage: 0°C, second stage: +80°C for warming up operation with LNG vapour, appr. 50°C for warming up and inerting operation with inert gas). l)
Crack open the manual steam supply valve SC313, 317(Ensure that the steam to deck is available and the isolating valve is open SC356).
a)
Switch the auto-control to manual.
b) Close the gas supply valve on the heater. Close the steam supply valve to the heater when the temperature at the heater outlet is above 0°C.
d) Open the steam side vent, then open the drain when all the steam has vented. Controls and Settings The gas outlet temperature is controlled by controllers CG518, CG523 on the inlet and CG519, CG524 on the gas heater bypass lines respectively. The steam condensate from the heater is returned to the drains system via the cargo steam drains cooler and the cargo escape tank, the latter of which is fitted with a gas detector sampling point. Boil-off Gas Heating configuration The same procedure is followed for venting and warming through the heater as described above, except that the temperature control is set for a gas outlet temperature of approximately +30°C.
4 - 26
Slowly open the manually operated steam inlet valve SC313(SC317).
b) Check the condensate level. c)
Set the LNG vapour lines as detailed for the operation to be taken.
d) Open the vapour outlet valve CG520(CG525) and the vapour inlet valve CG517(CG522). e)
In the CCR, set the controls for the boil-off heater on the IAS.
f)
Open the control air supply to the boil-off gas heater controls.
g) Set the temperature and level controllers to the correct settings for gas burning of +30°C. h) Monitor the gas vapour outlet and condensate temperatures. On completion of the operation a)
After the LD compressor has been shut down and the gas supply valve to the engine room shut, close the inlet valve to the heater CG517(CG522).
b) Shut the steam inlet valve SC313(SC317). c)
On completion of the operation;
c)
When the heater has been vented and warmed through, proceed as follows:
Open the hydraulically operated gas inlet and manually operated outlet valves.
m) Monitor the gas vapour outlet and condensate temperatures.
a)
The vapour lines will be set for using the LD compressor to deliver vapour to the LD gas heater. The HD gas heater can be used at emergency case for this operation by opening the cross connection valve CG 529.
Open the steam side vent and open the drain valve when all the pressure is off the heater. TAG NO.
DESCRIPTION
PIT2
Gas outlet pressure. Normal 95 kPag / Range 0∼160 kPag
TT2
Gas outlet temperature Normal +10°C ~ +80°C/ Range -100 ~+150°C
TIC2
Gas outlet temperature control Warm-up +80°C / Boil-off +45°C
TSHH2
Gas outlet temperature switch Normal +3 ~ +80°C / Range 0 ~ 150°C High-high Trip : 100°C
TSLL4
Condensate temperature switch Normal +150 ~ +190°C / Range 0 ~ 200°C Low-low Trip : +80°C
TT4
Condensate temperature TE4A Normal +150 ~ +190°C / Range 0 ~ 250°C
LS4A
Gas heater condenser level. High alarm
LS4B
Gas heater condenser level. High-High Trip
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.6a LNG Vaporizer
PIT 2
TE 2
P1 3
CG530 GAS OUTLET TO DEMISTER
F1
VENT
SC309
STEAM INLET
SC308
P1 1
LS 4B
HY 2
LS 4A
TSLL
4
ZS 2
HS 2
HIC 2
TE 4
LI 4 SC307
CD309 CONDENSATE DRAIN
TI D SC305 D
CS501
S
TCV 2 CS503
CS502 FC
LNG INLET
DRAIN
FCV 1
ZS 1
S
LNG VAPOUR
SV 1
HS 1 HIC 1
LNG LIQUID STEAM
PCV 6
PI 6 INSTRUMENT AIR SUPPLY
HY 1
4 - 27
Part 4 Cargo and Ballast System
LNGC DISHA 4.6 LNG Vaporizer
Cargo Operating Manual 2)
General Description (See Illustration 4.6a) The LNG vaporizer is used to vaporize LNG liquid, to provide gas when displacing inert gas from the cargo tanks with LNG vapour and for maintaining the pressure in the tanks when LNG is being discharged and vapour is not supplied from shore, and also for initial inerting in the insulation spaces with N2. Both LNG and forcing vaporizers are situated in the cargo compressor room. Specification Manufacturer: Cryostar Model: 65-UT-38/34-5.9 Mass flow: 10,788 kg/h (24,214 kg/h) Type: Shell and ‘U’ tube design(BEU) Heating medium: Saturated steam Inlet temp of steam: 169°C Inlet volume flow(LNG): 24 m3/h (54 m3/h) Outlet volume flow: 12,425 m3/h (12,659 m3/h) Inlet LNG temperature: -163°C Outlet gas temp: 20°C (-140 °C) Outlet pressure controlled: 30 kPag Steam Consumption: 4,882 kg/h (6652 kg/h) Steam Inlet/Outlet Temperature: 169/164 °C Note ! ( ) : LNG discharging without vapour return from shore
Purging of cargo tanks with vapour after inerting with inert gas and prior to cooling down. LNG is supplied from the shore to the vaporizer via the stripping/spray line. The vapour produced at the required temperature +20°C is then passed to the cargo tanks.
3) LN2 vaporization for inerting the cargo tank and insulation spaces(see ch.6.2.1).
i)
When vapour is produced, switch the control for liquid valve to remote and automatic. ! Caution Thorough checks around the LNG vaporizer and associated flange connections must be conducted during the operation. On completion of the operation.
4) Emergency forcing by manual operation: The LNG vaporizer can function as the forcing vaporizer when the forcing vaporizer has failed:
a)
Flow control: When the fuel gas demand from boiler is way in excess of the natural boil-off generation.
c)
Note ! This operation is the normal procedure if the cargo tanks have been inerted with inert gas containing carbon dioxide. Operating Procedures Set the LNG pipelines as detailed for the operation about to be undertaken.
b) Shut the steam supply valve SC309 when no LNG remains. Open the steam side vent and then open the drain when all steam has been vented.
d) Keep the vapour side valve open to system until vaporizer reaches ambient temperature. Control Process control is done on the outlet temperature from vaporizer with high and low temperature alarms. This is controlled on the TCV (temperature control valve) CS503. The steam condensate from the vaporizer is returned to the drains system via the cargo steam drains cooler and cargo escape tank, the latter of which is fitted with a gas detector sampling point.
LNG Vaporizer To prepare the LNG vaporizer. a)
Shut liquid valve CS501.
Open the shell side vent valve. The following alarms and trips are available:
Alarms are provided on the outlet gas temperature, high level and low temperature of the condensate water.
b) Crack open the shell side drain valve. Check that the condensate drain valves are open, SC307 and CD309.
The LNG vaporizer is used for the following operations:
c)
1) Discharging cargo at the design rate without the availability of a vapour return from the shore. If the shore is unable to supply vapour return, liquid LNG is fed to the vaporizer by using one stripping pump or by bleeding from the liquid header. The vapour produced leaves the vaporizer at approximately –140°C and is then supplied to cargo tanks through the vapour header. The vapour pressure in the cargo tanks will normally be maintained at 110 kPaA. (minimum 104 kPaA) during the whole discharge operation. Additional vapour is generated by the tank sprayer rings, the LNG being supplied by the stripping/spray pump. If the back pressure in the discharge piping to the shore is not sufficient to have a minimum of 300 kPag at the inlet to the vaporizer, a stripping/spray pump will be used to supply liquid to the vaporizer.
Crack open the steam supply manual valve SC308 (making sure steam to deck is available).
d) When all air is expelled from the shell, shut the vent valve.
TAG NO. PIT2
Gas outlet pressure. Normal 30 kPag / Range 0~60 kPag
TT2
Gas outlet temperature Normal -140°C ~ +20˚C / Range -150 ~+100°C
TIC2
Gas outlet temperature control LNG Discharge: Purge: Inerting: Emergency forcing:
After about 30 minutes, when pressures and temperatures have stabilised on the vaporizer; e)
Slowly open fully the steam inlet manual valve (SC309).
f)
Open the instrument air supply to the vaporizer controls.
g) In the CCR, set the controls for the LNG vaporizer on the IAS mimic.
DESCRIPTION
-140°C +20°C +20°C -40°C
TSLL4
Condensate temperature switch Normal +150 ~ +190°C / Range 0 ~ 200°C Low-low Trip : +80°C
TT4
Condensate temperature TE4A Normal +150 ~ +190°C/ Range 0 ~ 250°C
LS4A
Gas heater condenser level. High alarm
LS4B
Gas heater condenser level. High-High Trip
h) Fill up the vaporizer with liquid using manual control. Check all flanges and joints for any signs of leakage. Cooldown condition of LNG inlet line is monitored by local temperature indicator.
4 - 28
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.7a Forcing Vaporizer
PIT 2
TE 2
P1 3
CG532 GAS OUTLET TO DEMISTER PS
F1
VENT TI
PT100
SC304
P1 1
HY 2
LS 4B LS 4A
TSLL
4 ZS 2
HS 2
STEAM INLET
HIC 2
TE 4
LI 4 SC303
CD308 CONDENSATE DRAIN
TI D SC301 D TCV 2 CS504
S
CS505 FC
FC
CS506
LNG INLET
DRAIN
FCV 1
ZS 1
S
LNG VAPOUR
SV 1
HS 1 HIC 1
LNG LIQUID STEAM
PCV 1
P1 INSTRUMENT AIR SUPPLY
HY 1
4 - 29
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.7 Forcing Vaporizer
This is made possible by:
General Description (See Illustration 4.7a) The forcing vaporizer is used for vaporizing LNG liquid to provide gas for burning in the boilers to supplement the natural boil off. Both the LNG and forcing vaporizers are situated in the cargo compressor room. The forcing vaporizer is used to supplement boil-off gas for fuel gas burning up to 105% MCR. The LNG is supplied by a stripping/spray pump. LNG flow is controlled by an automatic inlet feed valve which receives its signal from the Boilers Gas Management System. Specification Manufacturer: Model: Mass flow: Type: Heating Medium: Inlet temp of steam: Inlet volume flow(LNG): Outlet volume flow: Inlet LNG temperature: Outlet gas temperature max.: Outlet gas temperature controlled: Outlet pressure controlled: Heating Capacity: Steam Consumption: Steam Inlet/Outlet Temperature:
Alarms are provided on the outlet gas temperature, high level and low temperature of the condensate water.
1) Two knitted mesh filters inserted in the gas flow path to fractionate the droplets and create the necessary turbulence to break down the small droplets injected into a fine fog of liquid gas and also to moisten the mesh wires acting as vaporizing surface. 2) Two conical baffles installed in the tube to allow eventually accumulated liquid to be directed into the gas stream on the pipe bottom. Mist Separator (Demister) A mist separator is used downstream of the forcing vaporizer to serve as a moisture separator and prevent any carry over of liquid to the LD compressors. Both vaporizer tubes are fitted with spiral wires to promote turbulence ensuring efficient heat transfer and production of superheated LNG vapour at the exit of the tube nests. Specification Manufacturer: Model: Type: Mass flow: Inlet temperature:
An alarm is provided on the level of the drained LNG.
a)
Open the shell side vent valve.
b) Crack open the shell side drain valve. Check that the condensate drain valves are open, SC303 and CD308.
When vapour is produced, switch the control for the liquid valve to remote and automatic.
! Caution Thorough checks around the forcing vaporizer and the associated flange connections must be conducted during operation. On completion of operation. a)
Shut the liquid valve CS504.
b) Shut the steam supply valve SC304 when no LNG remains. c)
Open steam side vent and then open the drain when all steam has been vented.
d) Keep the vapour side valve open to the system until the vaporizer reaches the ambient temperature. Control Process control is on the outlet temperature from the vaporizer with high and low temperature alarms. This is controlled on the TCV (temperature control valve) CS506.
The following alarms and trips are available: TAG NO.
c)
A re-evaporator is also used to ensure that accumulation of non-vaporized liquid at the vaporizer discharge is avoided and that the output is at a stable temperature.
i)
The steam condensate from the vaporizer is returned to the drains system via the cargo steam drains cooler and cargo escape tank, the latter of which is fitted with a gas detector sampling point.
To Prepare the Forcing Vaporizer
The forcing vaporizer is equipped with a temperature control system to obtain a constant and stable discharge temperature for various ranges of operation. The temperature of the gas produced is adjusted by spraying a certain amount of bypassed liquid into the outlet side of the vaporizer through a temperature control valve and liquid injection nozzles.
Cryostar VMS-10/12-1000 Shell with in / out nozzles and drain 5,800 kg/h -40°C
h) Fill up the vaporizer with liquid using manual control. Check all flanges and joints for any signs of leakage. Cooldown condition of LNG inlet line is monitored by local temperature indicator.
Crack open the steam manual supply valve SC304 (making sure that the steam to deck is available).
d) When all air is expelled from shell, shut the vent valve. After about 30 minutes when pressures and temperatures have stabilised on the vaporizer.
DESCRIPTION
PIT2
Gas outlet pressure. Normal 20 kPag / Range 0~60 kPag
TT2
Gas outlet temperature Normal -40°C / Range -150 ~+100°C
TIC2
Gas outlet temperature control Nat. Gas: -40°C Pure Methane: -60°C
e)
Slowly open fully the steam inlet manual valve.
TSLL4
Condensate temperature switch Normal +150 ~ +190°C / Range 0 ~ 200°C Low-low Trip : +80°C
f)
Open the instrument air supply to the vaporizer controls.
TT4
Condensate temperature TE4A Normal +150 ~ +190°C / Range 0 ~ 250°C
LS4A
Gas heater condenser level. High alarm
LS4B
Gas heater condenser level. High-High Trip
g) In the CCR, set the controls for the forcing vaporizer on the IAS mimic.
4 - 30
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.8a Vacuum Pumps
XA
XA
VP002
VP004
* FOR NO.1 & NO.2 PUMP
COMMON TRIP.
COMMON TRIP.
START HS
1
FROM STARTER PANEL
0
2
3
CI
4 5
7
8
* I.S BARRIER PANEL (E/D ROOM)
STOP
CI
HS
0 1 2 3 4 5 6 7 8 0
6
RI
RI VP001 VP003
NO.1 P/P NO.2 P/P MOTOR CUR. MOTOR CUR.
TO NO.1 P/P TRIP
XL TO NO.2 P/P TRIP
RI
REMOTE HS
XL
HS
START REMOTE STOP
NOTE : 1. THE ITEM MAKED WITH * TO BE SUPPLIED BY MAKER.
*
O
120 C~215 C O
2. ONE(1) ZENER BARRIER (INTRINSICALLY SAFETY BARRIER) PANEL ISTALLED IN E/D ROOM SHALL BE SUPPLIED BY MAKER (M.P.R.I).
-70 C~200 C TI
O
O
3. LOCAL CONTROL PANEL INSTALLED IN CARBO COMP. ROOM SHALL BE SUPPLIED BY MAKER (M.P.R.I).
* TS *
FOLLOWING ITEMS SHALL BE PROVIDED ON LOCAL PANEL
TI8
TO NO.4 VENT MAST
TSH2
0~100kpa PI P16 *
- MODE SELECTION (LOCAL / REMOTE)
TS * -5 C~60 C O
- TRIP INDICATION
LS *
- START/STOP WITH RUM INDICATION
PI106 (0~100Kpa) PI
FS *
LSL1
*
TI *
LS *
TI9
6. ALL LOCAL INSTRUMENTS FOR VACUUM PUMP SHALL BE INSTALLED IN CARGO COMPRESSOR ROOM.
LSL101
* TI
-5 C~60 C O
O
O
TI108
- EMERGENCY STOP
NO.1 VACUUM PUMP UNIT
- LAMP TEST
LI *
*
-100~60Kpa
##PI203
TS *
FG102-105 -0.1~0.9Mpa
TI7
-0.1~0.9Mpa
PI *
##PSL202
PI *
PI7
PRI. SPACE SEC. SPACE
PI107
*
-70 C~100 C O
* PI * *
LI *
O
*
TSL1
PS *
FW333
-70 C~100 C TI O
PI
NO.2 VACUUM PUMP UNIT
FG2~5
O
-100~60Kpa
TI109
F335
-60 C~-25 C O
TS *
* -100~60Kpa CN585
O
TI
PI
*
* TO STARTER * SOV101
CN587 FW332
-20 C~120 C O
TI107
*
* * SOV1
CN582
PT 100
TSL101 TSL101
TO STARTER
*
7. 6SETS OF PT100(2SETS FOR VACUUM PUMP BEARING TEMPERATURE AND 1SET FOR BULKHEAD SEAL TEMPERATURE PER EACH EQUIPMENT) SHALL BE PROVIDED. THOSE TEMPERATURE SHALL BE INDICATED ON THE IAS AND LOCAL.
TI *
-70 C~200 C O
*
- MOTOR ABNORMAL
CN581
5. SPACE HEATER (TR106 & TR6) FOR ELECTRIC MOTOR SHALL BE PROVIDED BY M.P.R.
FSL101
TSH102
O
FSL1
*
4. THE ITEMS MARKED WITH ** TO BE SUPPLIED BY MAKER AS LOOSE.
FS *
O
TI HT104
FW334
COOLING WATER OUTLET
COOLING WATER INLET
4 - 31
LOCAL
IAS-SYSTEM
STARTER PANEL
LOCAL PANEL
ELEC. CABLE
PNEUMATIC
HYDRAULIC
PIPING
UA1
UA2
COMMON TRIP
COMMON ALARM
Part 4 Cargo and Ballast System
LNGC DISHA 4.8 Vacuum Pumps (See Illustration 4.8a) Two vacuum pumps located in the cargo compressor room are used to evacuate the primary and secondary spaces atmosphere in the following cases: To replace air with nitrogen. To replace methane with nitrogen for gas freeing before dry docking or after there has been leakage of cargo. To test tightness of the membranes at regular intervals or after membrane repairs. When the associated tank is opened up. The pumps are driven by electric motors situated in the electric motor room through a gas tight bulkhead seal. The two pumps are used in parallel to evacuate the primary and secondary spaces in order to reduce the time taken to achieve the vacuum of 20 kPaA The pumps are fresh water cooled from the auxiliary fresh water system (refer to 5.5). The pumps are started and stopped from the starter panel in the cargo switchboard room or locally in the cargo compressor room. ! Caution If there is a failure or stoppage and the vacuum pump is hot and the cooling water has stopped, wait for the vacuum pump to attain room temperature before restarting in order to avoid shock due to cold water. ! Caution If the primary space pressure is reduced below the secondary space pressure there is a danger of distorting the secondary barrier by lifting it off its supporting insulation. A maximum pressure difference of 3 kPag is allowed. The suction pipe system on deck and inside the cargo deckhouse should be checked for leakages from time to time, especially before removing nitrogen gas polluted with cargo vapour.
Cargo Operating Manual Control and Alarm Settings Each vacuum pump will stop if the lubrication oil tank level, or flow is low, the discharge temperature is high or the suction temperature is low. Tag No.
Suction common pressure low trip Set point : -85 kPag
TSL1
No.1 Vac. pump suction temperature low trip Set point : -55°C
TSH2
No.1 Vac. pump discharge temperature high trip Set point : +170°C
VP002
No.1 Vac. pump common trip alarm
FSL1
No.1 Vac. pump C.W. outlet flow low trip
LSL1
No.1 Vac. pump oil tank low level trip
TSL101
No.2 Vac. pump suction temperature low trip Set point : -55°C
TSH102
No.2 Vac. pump discharge temperature high trip Set point : +170°C
Open the fresh water cooling water inlet and outlet at the vacuum pump.
Description
PSL202
Specification Manufacturer: Model: Type:
Operating Procedures
MPR industries P100 SV Two horizontal rotary dry vacuum pumps, single staged Deck central F.W system 48°C 1,250 m3/h 1,170 rpm 37 kW 20 kPaA 8 drips/m Flexibox
b) Check through the pump drain valve that there is no water in the pump. A sample intake is fitted on the drain valve to permit sampling during operation. c)
Vent the pump cooling water lines.
When evacuating the insulation spaces, the secondary barrier space is evacuated to 95 kPaA. before the primary barrier space suction isolating valve is opened. Both spaces are then taken down to 20 kPaA. This process ensures that it is not possible to lower the pressure in the primary barrier insulation space without having the same pressure in the secondary barrier insulation. d) Check the pump LO tank level. e)
Ensure the free rotation of the pump.
f)
Operate the manual LO pump and ensure that the oil drips are evident at each sight glass. If the pump has been stopped for more than 24 hours, it is essential to turn the rotor by hand 2 or 3 turns before starting the pump to ensure that the blades are not stuck on the cylinder.
g) The vacuum pumps can now be started.
Discharge from the pumps is led to the No.4 vent mast.
4 - 32
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.9.1a Custody Transfer System (CTS)
4x LEVEL GAUGE WITH PRESSURE TRANSMITTER
DOME FLANGE 6x MAIN TEMP SENSORS/TANK 6x SPARE TEMP SENSORS/TANK
4x LEVEL ALARM SENSORS
VERIFICATION PIN
99.0%
MOUNTING BRACKETS
98.5% SAAB STILL PIPE
2x 6 TEMP/TANK
THERMOWELL Ø32 MM(2x)
ARRY ATTENUATOR
FITTINGS FOR TEMPSENSORS
EXTERNALLY MOUNTED TEMPERATURE SENSOR FOR ZERO LEVEL
4 - 33
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.9.1b Custody Transfer System (CTS)
Omicron Base plate 4x LEVEL ALARM SENSORS
4 Input for CTS Override indication
4 Relay Output 98.5% Override indication to IAS 4 Relay Output 98.5% alarm to IAS 4 Relay Output 99.0% Override indication to ESD 4 Relay Output 99.0% Override alarm to ESD Time delay for 98.5% alarm is produced in the IAS
RELAYS CABLE DUCT
Alarm Panel
INTRINSICALLY SAFE INPUTS
OVERFILL ALARM SYSTEM TANK NO. 1 PORT TANK NO. 2 PORT
TANK NO. 1 ST.B. TANK NO. 2 ST.B.
TANK NO. 3 PORT TANK NO. 4 PORT
TANK NO. 3 ST.B.
ACCEPT ALARMFLASH
TANK NO. 4 ST.B.
CABLE DUCT
ALARM LAMP ON / OFF HOLD TEST
Standby Ship's 24VDC
EARTH BAR LOOP FAIL OMICRON SYST./POWER FAIL TONSBERG - NORWAY
Mains Supply 2x Serial interface to Workstation 98.5% Interface 99% Interface
DOT Alarm Printer Networked W/S
21"
Laser CTS Printer
UPS 230V
MAINS SUPPLY CABLE +10% -15%
230V
UPS
Level Unit (LU)
MAINS CABLE TO CONSUMERS
UPS
RS485
UPS
CABLE L=2m
Switch box
UPS
I/O-Box
UPS Relay Output System Failure
RS485
6x MAIN TEMP SENSORS/TANK
RS485
Field Bus
A1
RS485
A2
RS485
UPS
UPS
1x Serial Interface to IAS Digital remote tank indicators 1
2
3
4
SIOX A-A Cabinet
6x SPARE TEMP SENSORS/TANK
SIOX BUS
A1
A2
UPS 16 Realy Outputs for HH, H, L & LL level alarm 4 Relay Outputs for level alarm override 4x2 Spare Relay Outputs Ship's Master Clock ±24 VDC Puls input Analog Inputs from Trim/List sensor
4 - 34
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.9 Custody Transfer System
Verification by means of Test Cables The Gauges
4.9.1 Custody Transfer System 1. Introduction (See Illustration 4.9.1a, 4.9.1b) 1.1. Specification Saab TankRadar type level gauge : Temperature measuring system :
Pressure measuring system : Trim/list indicator : 1.2. Supplier: - Custody Transfer System
:
± ± ± ± ± ±
5.0 mm 0.2 °C @ -165 °C ~ -145 °C 0.3 °C @ -145 °C ~ -120 °C 1.5 °C @ -120 °C ~ +50 °C 1.0 % of Range (i.e. ± 6 mbarA) 0.5 % of F.S.
Saab Marine Electronics
The system normally consists of: y Workstation(s), one or more in redundant coupling y Level Unit y I/O box, for communication interfaces y Gauge(s), one for each tank, with integrated vapor pressure sensor and temperature inputs y Still pipe(s), one for each tank, made as segments y Pt100 temperature sensors in steel mantled tubing of specified lengths All distances are measured in ullage (distance from reference point to surface) during FAT. After installation onboard, distance between Saab reference point and ships reference point are defined. Tank Radar will then present Level with respect to “Surveyor” definitions.
Calibration of Test Cables
Trim/List Unit
Temperature correction during the Verification
A unit with inclinometers for measuring trim and list is intergrated in the Level Unit cabinet. These trim and list values are used to support the radar echo detection process that finds the true ullage These values may also be used for ullage/level correction if there are no better source of trim and list values available.
The temperature of the Test Cables must be within the range of 0 – 40°C during the verification. At any other temperature than 20°C , the Test Cables must be temperature corrected. The label on the Test Cables gas a table defining the “Value for Correction” for different temperatures. Measure the temperature near the Gauge.
Vapour pressure sensor
Note ! The Test Cables must have a stable temperature during the verification. Therefore, proceed with the verification as fast as possible. Prepare the Gauge for the verification first and then bring out the Test Cables to the Gauge. Try to keep the Test Cables in the protection box as much as possible. A sudden change of temperature in the Test Cable might affect the verification.
The vapour pressure sensor is installed in the Gauge housing and measures the absolute pressure in the tack. Caution Always use the ball valve in the guage to close the tank when replacing the vapour pressure sensor. Note ! Make a note of how the leads are connected to the wire terminal on the Electronic Box before you disconnect the leads.
2. Description
Temperature sensors
The Work Station
The Pt 100 temperature sensors are installed separately in a sealed thermowell submerged in the tank. Up to five temperature sensors are used to measure the vapor and liquid temperatures.
The Work Station is used by the operator to monitor tank levels, temperatures, vapor pressures and all other data handled by Saab TankRadar. It is slso used during configuration of the system and service. The Work Station does the alarm handling of the measured values. The Work Station communicates with other systems, such as load calculators and ballast level gauging systems and supervises the Gauge and the Level Unit. The level unit The level Unit contains terminals for the intrinsically sage connection of the Gauges. It contains the electronics used for processing the signals from the Gauges, for calculation the tank parameters, such as trim/list corrected level, average liquid and vapour temperatures etc and for communicating with the Work Station.
The Test Cable test is a complete electronics system test. A set of two Test cables is included in the system. One Test cable represents a 20% level and the other 80% level. The level the Test Cable represents is printed on a label on the Test Cable. The level is defined as the Calibrated Distance at 20°C
The Gauges measure the distance to the product surface using a continuous radar signal. The Gauges have an Electronic Box that generates and processes the radar signal. The LNG Radar Tank Gauge has a cone antenna inserted in the Still Pipe. The radar waves use the still pipe as a wave guide to the surface. Additional equipment for each tank, such as temperature sensors, caper pressure sensor, or the Local Display, ids connected to a wire terminal inside the Gauge housing. The vapor pressure sensor is placed inside the Gauge housing. The Local Display can display level, average temperature, and caper pressure of the tanks. The temperature sensors are placed in a thermowell and are connected to a terminal in the Gauge housing.
3. Verification Verification by means of Verification Pin The Verification pin test is a complete system test. It tests the lecel gauging function at a level slightly above the 100% level. a) b) c) d)
Open the “Verification” window on the Workstation. Hit the “Tank” button and choose what tank to verify. Hit the button “Start Verification” Compare the “Measured V distance” with the “Corrected V distance”
4 - 35
The test cables are certified instruments and must be calibrated regularly. A recommendation is to calibrate them every time a major overhaul of the system is pursued and at least every third year. See the Test Cable certification documentation in the On-Board binder.
Verification of Vapor Pressure measurement The verification is carried out with a certified pressure calibrator. a)
Connect the tube from the calibrator to the calibration inlet thread on the Gauge b) Close the ball valve. c) Check the pressure at 800 (80), 1100 (110) and 1400 (140kPaA) mbarA.
Verification of Temperature measurement A Resistance box can be used to verify the systems temperature measurement accuracy. The temperature sensors are removed and the resistance box is connected to the wire terminal. This requires a service password level and can only be done by a service engineer. Non-Contact Gauging with Radar The Transmitter emits radar waves towards the surface of the product. The reflected signal is received and processed in the Electronic Box. The signal is then sent to the Level Unit for further processing and calculation of the ullage.
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
The frequency of the transmitted signal decreases over a time period. The incoming signal is compared with the outgoing signal. The difference between these two signals is a low-frequency-signal. Its frequency is directly proportional to the distance from the Transmitter to the surface of the product. This is called the FMCW-method (Frequency Modulated Continuous Wave). Saab TankRadar uses its own advanced patented method to detect the surface echo and measure the distance to the surface accurately. The signal is filtered in a digitally controlled analog filter. First, a filter removes any echoes smaller than a threshold value. Then a narrow filter is applied around the frequency corresponding to the surface echo. The remaining frequency is compared with the one calculated in the previous sweep, resulting in a very accurate signal with a frequency of only a few hertz. With this method it is possible to achieve a very high accuracy. It uses the calculating power very efficiently, focusing on reliable and fast results.
Antenna
Set Point of Independent High Level Alarm Sensor 1) Tank Information Issued by ITS/NKK 100.00%
Tank No.
Volume
NO.1 & 4
99.00%
Height @ -160
Volume
Cargo TK
98.50% Height @ -160
Volume
Height @ -160
No. 1
21,935.797
26.761
21,716.439
26.190
21,606.760
25,924
No. 2
40,451.997
26.742
40,047.477
26.303
39,845.217
26,090
No. 3
40,442.934
26.740
40,038.505
26.301
39,836.290
26,088
No. 4
35,266.496
26.748
34,913.831
26.309
34,737.499
26,096
Total
138,097.224
136,716.252
NO.2 & 3 Cargo TK
136,025.766
2) Total distance between tank bottom and end flange on deck except gasket thickness. No.1 Tank No.2 Tank No.3 Tank No.4 Tank Distance 29.812 29.800 29.806 29.803 (meter) •
Rader frequency
3) Actual Measuring Length for Independent Sensors. Transmitted signal
Difference in frequency
T ra
nsm
itte
Re ds
fle c
ign
ted
al
s ig
Reflected signal
No.2 C. TK
No.3 C. TK
No.4 C. TK
Tank Total Height to Flange end from Tank Bottom
29,812
29,800
29,806
29,803
B: Extreme High Level (99.0 % in Volume)
3,622
3,497
3,505
3,494
A: Very High Level (98.5 % in Volume)
nal
Time
Unit : mm
No.1 C. TK
LEVEL ALARM SENSORS
3,888
3,710
•
The radar principle, the difference in frequency between the transmitted signal and the reflected signal is directly proportional to the ullage.
•
3,718
3,707
Remark
• •
The length A and B are based on atomoshpere temperature at measuring, 20ºC Maker should correct these data to -160ºC cryogenic condition.
Set point of target on the float is based on 160ºC from cargo tank bottom.
26756 mm
Distance from 100% volume to tank dome flange
3066 mm
Tank dome flange to saab upper Ref point
440 mm
Distance from zero tank level to 100% volume
26756 mm
Distance from 100% volume to tank dome flange
3074 mm
Tank dome flange to saab upper Ref point
440 mm
Extra length for bottom sensors
1000 mm
Length of T1
99.5 % Level
Length of T2
95 % Level
25418 mm
Length of T3
85% Level
22743 mm
Length of T4
50 % Level
13378 mm
Length of T5
25 % Level
6689 mm
Length of T6
Near Bottom
0.025 mm
26622 mm
Temp sensors in inserted from top of tank and down in thermowell We assume that 0% volume is your reference Please confirm our calculation. Example : Length of sensor T1: 26622 mm Actual length will be (440 + 3066 / 3074) + (26756 – 26622)
Activation of ESDS Activation of TPS2
Distance from zero tank level to 100% volume
NO.1 & 4 Cargo TK
NO.2 & 3 Cargo TK
1. Temp Sensor Length T6 CT1 and CT4
3640 mm
x4 pcs
2. Temp Sensor Length T5 CT1 and CT4
4844 mm
x4 pcs
3. Temp Sensor Length T4 CT1 and CT4
7519 mm
x4 pcs
4. Temp Sensor Length T3 CT1 and CT4
16884 mm
x4 pcs
5. Temp Sensor Length T2 CT1 and CT4
23573 mm
x4 pcs
6. Temp Sensor Length T1 CT1 and CT4
31262 mm
x4 pcs
1. Temp Sensor Length T6 CT2 and CT3
3648 mm
x4 pcs
2. Temp Sensor Length T5 CT2 and CT3
4852 mm
x4 pcs
3. Temp Sensor Length T4 CT2 and CT3
7527 mm
x4 pcs
4. Temp Sensor Length T3 CT2 and CT3
16892 mm
x4 pcs
5. Temp Sensor Length T2 CT2 and CT3
23581 mm
x4 pcs
6. Temp Sensor Length T1 CT2 and CT3
31270 mm
X4 pcs
99.0%
98.5%
4 - 36
Part 4 Cargo and Ballast System
LNGC DISHA 4.9.2 CTS Operation 1. WS Basic Four part The Work Station software mainly consists of four parts. 1) The Operation part During normal operation, you will mostly use the Operate part of the Work Station software. This is where you can view each individual tank, you can set alarm limits, you can view ship data like trim/list (a standard inclinometer is included in the system ), start and view trends, set up and view groups of tanks and view alarm summaries etc. 2) The Configure part The Configure part of the software is used to configure the database that contains all the information that is specific for your ship. It is normally only used when commissioning the system or when changing any part of the configuration afterwards. You can view everything in the Configure pare, but when you try to save any changed data, a password is required. 3) The Service part The Service part of the software is used when servicing the system. You can view everything in the Service part, but when you try to save any changed data, a password is required.
Cargo Operating Manual c)
To use a Menu button When you click a menu button, a menu is opened. The menu has alternatives that you can choose from. The alternatives can be sub-menus with more alternatives or items that open a window when you choose that alternative The “Channel” and “Tank” menu buttons work in a special way. When you use them you don’t change windows. Instead you change the tank or channel that the window is presenting. This means that if you have displayed the “Tank Data” window for CT1P and you want to view CT2P instead, you can change tank with the “Tank” menu button.
2. Cargo composition setting The vapour in the tank affects the radar measurement. Therefore, to achieve the highest possible accuracy, the composition of the cargo must be entered in the TankRadar WS for each tank. In the case of setting the cargo composition in the WS, the composition can be air, one product or a mixture of more than one products. The cargo composition is easily changed by choosing another Cargo composition label. When a not yet defined cargo composition is to be loaded. The composition has to be defined in the “Setup:Mixture” window, see instruction below:
4) The Help part To set a Previously Defined Cargo Composition The Help part function is based on SAAB TankRadar operating manual so you will basically find the same texts and figures in the Help part as in SAAB TankRadar operating manual. However, the Help part is made in an interactive way so that, for example, when you click an item in the table of contents, the corresponding page is displayed. Most of the figures shown are also interactive, so that by clicking a button, the corresponding menu will be displayed. Main bar
1) To add a new Composition a)
Setting Setting let you select data from a fixed number of options. There can be exclusive and nonexclusive setting. With a nonexclusive setting, more than one item can be selected at the same time.
a)
Click the “Cargo composition label” of the tank you want to change. This requires the Operator level password. - The “Cargo Mixtures” menu is displayed.
b) Click the new cargo composition for the tank - The menu is closed and the composition and label for the tank are changed
You can now do the following: Add a new composition. Edit the text in “Long Name” and “Short Name” by clicking the text and entering the new names. - Edit the text of a label. - Edit the color of the text and/or the background. - Edit the components in the Composition. -
The number of possible compositions is set in the top of the window. Click the figure “Number of mixtures used” and increase the figure with as many more compositions as you need.
b) Edit the text and color of the label according to below instructions. c)
Edit the “Components” according to below instructions.
d) Do one of the following: - If you have completed editing the cargo compositions, click the “Save” button and then the “Close” button. - To cancel the editing, only click the “close” button and then the “discard”button in the pop-up menu. 2) To edit the text of a label a)
In the “Setup : Cargo Compositions” window, change the text in “Long Name” and/or “Short Name”.
b) Do one of the following: - If you have completed editing the cargo compositions, click the “save” button and then the “Close” button. - To cancel the editing, only click the “close” button and then the “discard” button in the pop-up menu. 3) To edit the background color or text color of a label a)
In the “Setup Mixture” window, find the number for the color you want. Each color, presented to the lower right, has a number.
b) Enter that number for the “Text Color” and/or “Background Color” The “Main bar” is located at the top of the screen. The bar contains the “Window” menu button, the TankRadar name, the date and time, a “Help” button and a “Close All” button. Alarm bar The Alarm Bar is located at the bottom of the screen, it is always present You can place windows in front of the “Alarm Bar” but when an alarm is presented, the “Alarm Bar” is displayed in front of the window.
To edit and add Cargo Compositons c) a)
In the “Setup Mixture” window (Window▼Setup►Mixtures), click the “Mixture” button. - A menu is displayed.
Do one of the following: - If you have completed editing the grades, click the “Save” button and then the “Close” button. - To cancel the editing, only click the “Close” button and then the “discard” button in the pop-up menu.
b) Click the Composition you want to edit. - The name and settings for the mixture are displayed in the window
4 - 37
Part 4 Cargo and Ballast System
LNGC DISHA 3. Cargo Handling Monitor Basic monitoring The base for all cargo monitoring is the “Overview” mimic. It gives a fast overview of the most important information you need, such as Level, pressure and Temperature. The “Overview” mimic and all the other mimics are unique for each vessel. The “Overview” mimic has an image of the vessel and the tanks. The image is custom made to look like the actual vessel and therefore make it easier to find the tanks. This also means that the mimic will look different on different vessels. There can also be different information in the “Overview” mimic for different vessels. 1) Ship unique data There can be fixed areas in the “Overview” window with information about for example draft, seawater density, trim and list.
Cargo Operating Manual The information you find in the “Tank Data” window is different for every vessel. It can be level, average temperature, pressure, level rate, volume, weight and alarm limits. 1) To open the Tank Data window Open the Tank Data window by doing one of the following: - Click the green “Information” button on the “Overview” mimic for the tank you want to view. - Click the bar-graph in the tank information area of the tank you want to view and choose “Tank Data” from the “Channel” menu that is displayed.
3) Tank information Each tank is graphically described with a representation similar to the one below. The name of the tank is preset at delivery and cannot be changed. The liquid in the tank is described with the bar-graph. The bar-graph indicates the level. The Cargo composition must be changed when you change cargo in the tank. The “Mixtures” menu is displayed when clicking on the cargo composition label. Both the Vapour pressure and the average temperatures can be presented in the tank information area. This is different on each vessel. To open the “Tank Data” window click on the bar-graph or directly on the values below the tank. The alarm limits indicates limits such as Lo, Lo Lo, Hi and Hi Hi. Detailed Tank information-Tank Data Window Open the “Tank Data” window when you want to view the data for one tank. The “Tank Data” window displays more detailed information for one tank at a time. You can also open a number of “Tank Data” windows. One window for every tank you want to observe for the moment.
The “Sysfail” window contains a list of the present serious system failures within the TankRadar G3 system when the window was opened. The following failures can be included in the “Sysfail” window: -
Level Unit Communication Failed Level Unit Sysfail Level Unit Power Failure Level Unit LI Communication Failed I/O Box Relay Communication Failed
Alarms Alarms can be monitored in the “Alarm Row” and in the “Alarm window”. There are three types of alarms: -
2) Predefined buttons The “Overview” mimic might also have additional buttons. They might be for viewing predefined tank groups. One of these buttons could by configured to show for example the tanks at the aft end of the ship, another one the tank at the middle part of the ship. The buttons might also open other mimics. The other buttons are unique for each system but are mainly shortcuts to the functions you will find by clicking the “Window” button.
3) System Failure Summary
-
Alarm. A channel can have one or more alarm limits. When the value of the channel passes the alarm limit the channel gets alarm status. As an example, the value for the level channel for one tank can pass the limit for Hi and get the Hi alarm status. Sysfail. The Sysfail alarm indicates a serious system failure in the Saab TankRadar system. Warning. The warning alarm indicates a failure that normally is not so serious for the system.
1) Alarm Summary The “Alarm summary” window displays all the channels that were in alarm when the window was opened. They are displayed with their status, their value, the limit that caused the channel to go into alarm and the unit with which the channel is presented. The “Alarm Summary” can contain an unlimited number of rows. The alarms for each tank are grouped together in the summary. 2) Warning Summary The “Warning Summary” window lists all failures that normally do not seriously affect the TankRadar G3 system. The window lists the failures that were present when the window was opened. The following messages can be included in the “Warning Summary” window: -
Level Unit Ground Failure Level Unit Memory Failure Master Communication Failed LevelDatic Communication Failed SIOX Communication Failed Level Unit Restarted Gas Correction Failure
4 - 38
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Computer Cargo Record Sheets CUSTODY TRANSFER MEASUREMENT DATA
CUSTODY TRANSFER MEASUREMENT DATA
BEFORE LOADING
AFTER LOADING
SHIPS NAME DATE (DD/MM/YYYY) TIME (HH:MM) PORT/BERTH NAME VOYAGE NO CARGO NO CHIEF OFFICER
INSPECTION COVER 8" X 8" X 8" TEE SAMPLING INTAKE VALVE
HAZARDOUS AREA 8" GATE VALVE
ALARM OUTPUTS
SIGNAL OUTPUTS
LEVEL ALARM OUTPUTS RL 1
COM NC NO
SIGNAL OUTPUTS
GLASS FIBRE
LEVEL ALARM OUTPUTS
SIGNAL OUTPUTS
LEVEL ALARM OUTPUTS
RL 3
RL 4
RL 1
RL 2
RL 3
RL 4
RL 1
RL 2
RL 3
COM NC NO
COM NC NO
COM NC NO
COM NC NO
COM NC NO
COM NC NO
COM NC NO
COM NC NO
COM NC NO
COM NC NO
4-20 mA
ALARM OUTPUTS
SIGNAL OUTPUTS RL 4
COM NC NO
4-20 mA
LEVEL ALARM OUTPUTS RL 1
RL 2
RL 3
COM NC NO
COM NC NO
COM NC NO
HENRI SYSTEMS HOLLAND BV
HENRI SYSTEMS HOLLAND BV
AMTG 821/02 REMOTE LEVEL INDICATOR
AMTG 821/02 REMOTE LEVEL INDICATOR
AMTG 821/02 REMOTE LEVEL INDICATOR
AMTG 821/02 REMOTE LEVEL INDICATOR
Circuit [EEx ia] IIC Approval no : KEMA nr. Ex-93C7922 Sensor output : U<11V I<14 mH Supply voltage : 12 VDC/3A max
Circuit [EEx ia] IIC Approval no : KEMA nr. Ex-93C7922 Sensor output : U<11V I<14 mH Supply voltage : 12 VDC/3A max
Circuit [EEx ia] IIC Approval no : KEMA nr. Ex-93C7922 Sensor output : U<11V I<14 mH Supply voltage : 12 VDC/3A max
Circuit [EEx ia] IIC Approval no : KEMA nr. Ex-93C7922 Sensor output : U<11V I<14 mH Supply voltage : 12 VDC/3A max
+ POWER
BLUE MARKED AREA 4 .. 20 mA OUTPUT SIGNAL
HENRI SYSTEMS HOLLAND BV
+ POWER
+ POWER
BLUE MARKED AREA
+ POWER
BLUE MARKED AREA 4 .. 20 mA OUTPUT SIGNAL
RL 4
COM NC NO
4-20 mA
HENRI SYSTEMS HOLLAND BV
INSULATION PIPE
TANK CEILING
ALARM OUTPUTS
RL 2
4-20 mA
WEATHER DECK
ALARM OUTPUTS
BLUE MARKED AREA 4 .. 20 mA OUTPUT SIGNAL
4 .. 20 mA OUTPUT SIGNAL
1.5 MM INVAR
PRIMARY BARRIER
100
SAFE AREA(CCR)
HOLE OF 20MM INTERVAL OF 150 MM
4 - 43
Part 4 Cargo and Ballast System
LNGC DISHA 4.9.3 HSH Float Level Gauge (See Illustration 4.9.3a) General The HSH float level measurement system is of membrane tank type, but uses a invar wire to compensate for temperature variations. A gauge head, containing a mechanical indicator, a invar wire tensioned by a tensator spring and a 140 mm diameter float attached to the lower end of the wire, is fitted to each liquid dome. The shrinkage of the float in LNG is indicated in the volume table and the minimum level which can be read from the gauge is 145 mm. ! Caution To reduce the risk of tape failure and wear on the gauging mechanism, the floats should be fully stowed at all times, except when taking a sounding. Care should be taken when stowing the float as excessive tension may cause wire breakage. To obtain the liquid level, the float is released from its stowage position using the release lever and allowed to descend freely to the liquid surface. The tank sounding may then be read from the meter. The HSH gauges are checked against the SAAB CTS during each alternate loading. Each tank is provided with an approved secondary level measurement system. This secondary system provides an alternative means of cargo level measurement in the event of failure of the SAAB measurement system. The HSH ‘806 Level Gauges’ is based on float gauges fitted to each cargo tank, the gauge heads incorporating local mechanical read-outs and electronic transmitters to provide remote level indication. Cargo tank levels measured by the HSH system are displayed on remote level indicator fitted on the Cargo Control Room console. System Components The HSH system comprises a level gauge assembly for each cargo tank and electronic equipment. The level gauge assembly is mounted on an assembly comprising a float well, isolating valve and inspection chamber.
Cargo Operating Manual Isolating Valve and Float Inspection Chamber A 200 mm gate valve, bolted to the top of the float well, allows the gauge head to be isolated for maintenance. A inspection chamber is mounted above the isolating valve to provide access to the float and for connection of special float recovery tools in the event of wire breakage.
Operation Gauging a)
OPEN the gauge isolating valve fully, (normally left OPEN).
Level Gauge Assembly The level gauge assembly comprises a gauge head and float assembly.
b) Put the crank handle in the stored position, i.e. with the handle towards the gauge cover.
The level gauge incorporates a float assembly, clamped to an accurately perforated wire manufactured from invar, a viscous damper to control the rate of descent of the float to the cargo level, a crank for raising the float to the storage position, a mechanical read-out and an intrinsically safe transmitter for remote read-out. When the float has reached the highest point, the hand crank ships through the magnetic coupling and the measuring drum is automatically locked.
c)
Engage the hand crank and turn one (1) revolution clock-wise.
d) Remove the hand crank when the float is released. e)
Float release is visible at the local read-out.
Returning the Gauge to the Stored Position. Remote Display System Apart from the gauge-mounted transmitters, the remote display system comprises a display cabinet and a power supply rack, a translator rack and an input rack. Power supply unit is located in the Cargo Control Room console. Intrinsic safety circuit is installed in the Remote Level Indicator. Level Transmission The transmitter in the level gauge is supplied the remote level indicator with three separate level transmission signals. These signals are DC level pulses generated by three inductive proximity switches in the level gauge, and are amplified and buffered in the remote indicator. The three conditioned logic signals are then fed into a programmable logic device which generates an up or down pulse on its output for every mm level change of the gauge float. A bi-directional digital counter memory is controlled by these up and down pulses and the actual counter value is directly proportional to the liquid level in the cargo tank.
a)
Put the crank to the cranking position, i.e. with the handle outwards.
b) Carefully raise the float by turning the crank slowly in a counter clockwise direction, c)
The magnetic coupling of hand crank and hoisting mechanism prevents over-winding.
d) When the float has reached the highest point, the hand crank slips through the magnetic coupling. e)
At the highest point of the float, the measuring drum is automatically locked.
f)
Check the local read-out level.
g) The hand crank must be removed.
Float Well The float well comprises a 200 mm-diameter tube installed vertically within the cargo pump tower. The upper end of the float well penetrates the top of the tank dome where it terminates in a flange. The lower end extends to within 75 mm of the bottom of the tank where it is closed by a perforated plate. The lower end of the float well is provided with a bolted inspection cover. Expansion is allowed for by a sliding connection just below the dome penetration. To avoid level errors caused by the ‘still well’ effect, there is a 25 mm diameter hole spaced every 150 mm below the sliding connection.
4 - 44
Part 4 Cargo and Ballast System
LNGC DISHA ! Caution Never remove a measuring drum before locking the spring motor. Remove the oil fill plug and fit the lock tool. Failure to do so will unwind the spring-motor and cause severe damage. The oil in the spring-motor compartment does not have to be drained in order to lock the spring-motor. Fit the measuring drum in exactly the same position as it was taken out, e.g. with the float at the same level. If this is done correctly, readjustment of the level gauge is not required.
Cargo Operating Manual Recovery Procedure for Float Breakage a) If a float is lost, the spring motor will wind itself up due to the missing counter weight of the float. b) It is then safe to close the gate valve below the level gauge and remove the measuring drum side cover. c) Judge if there is still enough measuring wire on the measuring drum (max. capacity is 37 meters, tank height is approx. 33 meters).
Maintenance
d) If necessary fit a new measuring wire.
The HSH system must be operated at regular intervals to ensure that the system is available in the event of failure of the primary and back-up measuring system. The stored reading and error between the HSH and the Custody Transfer System (CTS) should be recorded at each operation.
e) Attach the float recovery device to the end of the measuring wire in the same way as a float is attached.
The float must not be left at the liquid level after gauging because constant movement of the tensator spring, that ensures tension on the tape, will lead to premature failure. The oil filling of the level gauge should be renewed preferably once a year. The terminal box should be checked for moisture once a year. The bearings of the level gauge should be checked every 2~3 years. At same time, check the measuring cable and float for corrosion.
f) Drain the oil compartment and open the side cover. g) With the measuring drum still outside, turn the main shaft of the spring motor counter clockwise until the local reading shows approx. the value of a normally hoisted float (approx. 32,500 mm). h) Install the measuring drum with the recovery device attached, close the drum side cover and open the gate valve, while holding the spring motor by hand to prevent it from turning. i) Once the gate valve is fully open, allow the spring motor to turn slowly down. j) When the spring motor stops turning, the recovery device has reached the float.
An inspection hatch is provided in the float inspection chamber for access to the float assembly and for retrieving the float in the event of wire breakage.
k) Now use the hand crank to turn the recovery device plus float slowly up. It may be necessary to assist the hand crank by helping to turn the spring motor clock wise by hand.
The gauge head is sealed with locking wire and lead seals by ITS/KIMSCO. It is important to avoid damaging these seals. In the event of these seals being broken, Head Office should be informed without delay in order that arrangements can be made for the attendance of ITS/KIMSCO to check and re-seal the gauges.
l) Close the gate valve when the local indicator shows the value as set in step g.
Wire Breakage In the event of Wire breakage, the Operator/Owner’s Head Office is to be informed, as any maintenance requiring opening of the gauge will necessitate the attendance of independent surveyor ITS/KIMSCO to recalibrate the gauge to satisfy buyers, sellers and customs. Instructions for recovery and replacement of the float assembly or wire are referred to the manufacturer’s instruction book.
m) Open the side cover and the side cover of the “T” pipe below the level gauge and remove the recovery device and float. n) Connect the original float in a normal manner to the measuring drum wire. o) Allow the float to rest on the closed gate valve and adjust the local indicator and reference switch to their original values. p) Close all side covers and refill the oil. q) The gauge is ready for use again.
The ship is provided with a fixed Trim-List Indicator system for the Custody Transfer System. Maker: Type: Range: Accuracy: Output:
Trim Indicator
Utsuki Keiki KK, Yokohama, Japan Detector CSM-2DD; Indicator TMW-4B and DVF-11E ± 2° trim ± 5° list ± 0.5% FSD 4~20 mA both channels
List Indicator
Electric Motor Room
The detector is installed in the Electric Motor room with indicators in the CCR console and wheelhouse. The measurement principle is that a suspended mass within the inclination detector moves from a centre position when the ship trim or list varies. The movement is detected by linear variable differential transformer coils. A local circuit unit box converts this into a 4~20 mA signal for each axis and these are fed into the CTS interface.
CB-2S Trim and List Signals to CTS
The detector is deck-mounted and protected by a wooden cover. As the response is set to 0.5 seconds, the system cannot give reliable readings under way.
Inclination Detector
The readings should be checked against draft marks in calm weather alongside periodically. Note ! The trim and list measurements in IAS are derived from the consilium panel and not this instrument.
Fwd
220V AC Port
Stbd
Aft
4 - 46
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.10a Nitrogen Generator
PERMEATE VENT TO ATMOSHERE
OFF-SPEC. VENT TO ATM.
TP 4
TP 3
400V, 60Hz EL. SUPPLY
220V 60Hz EL. Supply
Control Panel 5.1A XA
TAH
OAHH 1A
COMMON FAULT TAH
4A
440V 60Hz EL. Supply
PDA 4A
3A
OIT 1A
TAH 2A
CONTROL PANEL
PDS 4A
INLET FILTER
STARTER COMPRESSOR A
IV-12A TP 1A WS-2A
AFTER COOLER
M
WS-1A
FLEX. HOSE
TIC 2A
TS 1A
TE 2A
PDI 2A
PDI 3A
F2A
F3A
OIL FILTER
V-1A
PI 1A
IV-5A
TS 2A
PI 2A
V-3A
MS-1A
DN 40
IV-2A FIT 1A
DN 25
S V-20A
S
V-5A
V-6A
DN 25 CV-1A
V-2A
S
S
AD 2A
AD 1A
S
TI 1A
S XV-1A
FCV-1A
EL HEATER V-4A
NS002
MIT 1A
PCV-2A
NS003
OIL COOLER
DN 25
XV-2A
ME 1A
IV-1A EH-1A
OIL SEP.
TAHH 2A
S
IV-13A
TS 3A
TAH 1A
MAH 1A
CALIBRATION
IV-4A
FEED AIR COMPRESSOR FAC-1A
OAH 1A
XV-3A
AD 3A
V-7A
DN 50
Control Panel 5.1B
V-8
TAH
XA
4B
1B
COMMON FAULT
TAH
PDA 4B
3B
INLET FILTER
STARTER
PDS 4B
AFTER COOLER
WS-1B
FLEX. HOSE
TAH 1B
TIC 2B
PDI 2B
PDI 3B
TS 1B
TE 2B
F2B
F3B
V-1B
OIL SEP.
CALIBRATION TAHH 2B
S
IV-5B
MIT 1B
PI 1B
TS 2B
V-3B
MS-1B
DN 25
PI 2B
PCV-2B
PI 3
IV-2B
S
FIT 1B
DN 25
DN 25
V-4B S
AD 1B V-6B
S
AD 2B
TI 1B
V-2B
XV-1B
FCV-1B
EL HEATER
V-5B
PAL 5
CV-1B
PAH 5
S XV-3B
AD 3B
START/STOP SYSTEM
PI 5
START/STOP SYSTEM
PS 2A
PT 5
PS 2B
V-7B
IV-7
IV-10
E/R OUTSIDE
TP 5 HOPPER DSE-P5885S FOR VISUAL CHECKING
IV-6
S
TP 13
FROM COOLING F.W IN E/R
DN 25
ME 1B
TP 1B
OIL COOLER
MAH 1B
XV-2B
IV-1B EH-1B
OIL FILTER
OIT 1B
IV-13B
TS 3B
M
OAH 1B
TAH 2B IV-4B
IV-12B
COMPRESSOR B
OAHH 1B NOTE 2 440V 60Hz EL. Supply
FEED AIR COMPRESSOR FAC-1B CONTROL PANEL
220V 60Hz EL. Supply
PI 7
TO COOLING F.W IN E/R
IV-8
IV-11
V-14
SET : 1,000 kPa
HOPPER DSE-P5885S FOR VISUAL CHECKING
PI 6
SET : 5 barg BT-1
DRAIN LINE TO NEAREST E/R SCUPPER
V-13
IV-21
KEY
NITROGEN TO CONSUMER
COOLING WATER
V-15 PCV-4A PI 8
COMPRESSED AIR NITROGEN
CAPACITY: 2X120 Nm3/h AT 97%
DN 25 SET : 3 barg
V-11
IV-22 NITROGEN TO CONSUMER
NITROGEN BUFFER TANK
PCV-4B
37 m3 1000 kPA
TP 11
DN 25
V-10
TP 10
V-12
4 - 47
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.10 Nitrogen Production System General Two nitrogen generators installed in the engine room produce gaseous nitrogen. This is used to the pressurize the barrier insulation spaces as seal gas for the HD and LD compressors, extinguish fire in the vent mast, and purge the fuel gas system and various parts of the cargo piping. The two high capacity units (120 Nm3/h each) are able to produce 240 m3/h of nitrogen, which is mainly required for topping up the barrier insulation spaces during loading, cooling down and other services like extinguish fire in the vent mast and sealing the compressor. The operating principle is based on the hollow fibre membranes through which compressed air flows and is separated into oxygen and nitrogen. The oxygen is vented to the atmosphere and the nitrogen stored in a 37m3 buffer tank this is ready for use. The high capacity units each consists of a Tamrotor EML 85/13 EWNA screw type compressor cooled from a fresh water cooling system, a single-staged air/water separator, three air filters arranged in series, and a 3kW electric heater before passing into the membrane units. An oxygen analyzer after the membrane monitors the oxygen content, and if out of range above 4% O2, redirects the flow to the atmosphere. The nitrogen is stored in a 37m3 buffer tank where high and low service pressure set points actuate the operation of the generators. High Capacity Unit Manufacturer: Nominal flow rate: Delivery pressure (min/max): Dew point at atmos. press: Outlet gas composition: Screw compressor; Tamrotor FL85-13: Compressed air at membrane inlet: Maximum back pressure O2 enriched air: Nominal power: System operating temperature range:
Air Products 120 + 120 Nm3/h 600 / 950 kPag -70°C Oxygen 3% (% vol) Nitrogen balance to 100% (% vol) As required As required
Membrane inlet operating temperature: +50°C Oil residual content: < 0.003 ppm Filtration efficiency for Oil residual content: < 0.003 ppm Dew point (with drying capability of membranes, final dew point will be < -55°C) -20°C Four independent time operated condensate drain valves. Hollow fibre membrane unit with dry filters having the following characteristics (at 50°C inlet temperature) 120 + 120 Nm3/h, N2 97%, O2 residual 3%. The membranes are provided with a back-pressure control valve down stream from the flowmeter that maintains a constant membrane pressure.
Alarms and Shutdowns Alarm Item No.
Description
Shut-Down
TAH-1A
Air heater high temp:
200°C
TAH-2A
Feed air high temp:
60°C
TAH-3A
Compressor high temp:
50°C
TAH-4A
Compressor motor winding temp. high 150°C
MAH-1A
Dew point level high:
-60°C
OAH-1A
Oxygen content high:
3.50%
OAHH-1A
Oxygen content high-high:
4.00%
XA-1A
Compressor fault
PDAH-4A
Filter diff. pressure high:
60kPa
PAL-5
Buffer tank pressure low:
300kPag
PAH-5
Buffer tank pressure high:
800kPag
TAHH-2A
Feed air high high temp:
65°C
o
o o
o o o
The nitrogen generators are equipped with an oxygen analyzer that continually monitors the oxygen content in the nitrogen output. If the level of oxygen rises above 1% of the design value, then an alarm is activated in the console. If the level of oxygen rises further, the high high alarm operates by redirecting the flow to atmosphere and closing the discharge line in the buffer tank.
Oxygen Analyzer
The gaseous nitrogen generators are operated automatically, locally or from the CCR via the IAS.
A fixed O2 content analyzer is installed in the package units and connected before the remotely operated three way valve.
Control Systems and Instrumentation
The analyzer has the following characteristics; O2 range from 0 to 25%, with an output signal of 4 to 20 mA for the remote indicator, alarm panel and three way valve actuation.
The control panel permits fully automated unmanned operation of the units. The following alarms and controls are mounted in the control panels.
o
Push buttons for start/stop operation; System status indications; Push button for audible alarm acknowledgement; Continuous N2 delivery pressure; Continuous O2 content reading; Dew-point analyzer; Electrical heater temperature control; and Emergency Stop push button.
0.05 kPag 2 X 79.5 kW 0°C to 50°C
4 - 48
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.11a Inert Gas and Dry Air System
PI 1503
1501
PZA 1505
1504
INSTRUMENT AIR
PIC 2112
WEATHER DECK
IG006
PIC 1509 TI 2311
COOLING WATER IG035 WITH OPEN/CLOSE LIMIT SWITCH
TZA 2312
PC 4209
H
2307
S
PI 1636
PI 1003 1006 1002
PI 2037
1004 P 1051 1052
FUEL OIL 1001
M
L
1637
2038
P
H
XZA 2022
TI 1639
MAIN B URNER 2001
1059 2032 2042
4021 4123
FILLING 2308
XZA 2121
WASHING / COOLING TOWER
L
TI 4026
PI 2012
H
2013
PZA 2010
PZA L 2011 H
2050
2322a
H LZA 2322
CHAM BER
4109 4108
RINSING WATER HOSE CONN. 4015 Tracing and S insulation
LUB OIL CHARGING + DRAIN 4016
2202
AMBIENT AIR
2315 2201
2203
E-MOTOR
2319
M
2223
DPT 2411 2410
2323
G 24 C 21
2226 2224
1621 1602 1601
CONDENSATE 1605
1623
PC 1624
PI 1626 1624
1625 1606
GS b
5405
5021
S
5301 5302
4135
4321
4113
4319
H
5306
SAMPLE LINE A
4111
PC 4211
5304
INSTRUMENT AIR
TI 5225
FILLING 5004
DRAIN
TZA 5409
SCREEN 5407
FILLING 5005
PT 6006 6005
P 5402
A TZA 5216
DEWPOINT ANALYSER TAG No. 7100
PI 5251
VESSEL 1 5002
PI 5061 5062
H
M 5404
FAN 5403
5252
4011 4138
AMBIENT AIR
5401
PZA 5305 L
P 5092
P 5082 GS a
GS b
GS a
5081
1603
1632 S
P 1631
DRAIN / DECOMPR. DRAIN WITHIN CHAMBER COAMING
1604
AS PZA 1634
ORIFICE TO BE ADJUSTED ON BOARD
GS b
PI 5071
VESSEL 2 5003
5072
5110 STEAM HEATER 5101
PI 5105
5091
S 2416
TO BILGE HOLD TK RINSING WATER HOSE CONN.
IG031
R404A DISCHARGE TO OUTSIDE
G a/b S
PACKAGE UNIT
AS OVERBOARD VALVE 4322 (IG027) WITH OPEN/CLOSE LIMIT SWITCH
PIC 4303
TI 4326 PCV 4324
5109 5108
5106
LI 4308 4305
4031
VENT
4309
CONDENSOR 4301
LC 4311 4316 4317
5031
P 5042
5051
5041 GS b
GS b
4313
S 5104
H
P 5052
5043
4307 4310
S
PCV 5113
DRAIN WITHIN DRYER COAMING
5033
4318 R404A DRAIN
5112
S 5053
4314
TZA 5416
PI 5114
5113
5111
5103 5102 CONDENSATE
5411 ELECTRICAL HEATER STEAM
GT 4323 WATER SEAL 4325
FRESH WATER
KEY
FRESH WATER 4327 FRESHWATER TO DRYER UNIT
SEA WATER
PT 4304 PC 4321
WASHING / COOLING WATER OVERBOARD
AS
4306
5008
P 5032
DRAIN WITHIN DRYER COAMING
4315
24 P 20
S
5007
4312 AS
GS a/b
2316
L
1635
PIC 2415
24 19 2415
P 2417
PIC 1633
BLOWER 2 PI 1622
STEAM
P
4010 TC 4019
PI 111U
PC 8007
BLOWER 1
2225
E-MOTOR
DRAIN
4030
2222 2221
4139
SCANTLING DRAFT 2314
COOLINGWATER
TI 2317
PZA 2320 L AMBIENT AIR
4007
OIL SEPARATOR
2324
2206 2204
2205
M
H PZA 2321
4119
PC 4212
4005
PI 2318
GS a
5436
5437 DRAIN
5028
P 5022
GS b
COOLINGWATER
TI 5408
DEMISTER VESSEL
4116
DRAIN
EXCESS AIR (HOT) TO OUTSIDE.
GS b
COOLER
4120
MOTOR
2055 (IG003)
GS a
S
4137
R404A COMPRESSOR
2313 (IG038)
2015
P 5012
4414
P 5027
5024
5014
5018
5026
5023
5013
5458 DRAIN WITHIN DRYER COAMING
4012
4130
COMB USTIO N
2014 UPP DK
4129
4217 4213
S
S
5016 GS b
5011
2003
F.O. PUMP
SAMPLE GAS TO OXYGEN ANALYSER
S
4023
P 5017 S
PI 4415
4131
4133
PZA 4003
RATOR EVAPO
R404A CHARGING 4128
5459
DRAIN WITHIN DRYER COAMING
5442
S
5440
TI 5056
TI 5055
TC 5057
5456 5453
5457
LIQUID SEPARATOR
4204
4205
S
PILOT BURN ER
2040
4125
TI 4225
2344 2103
1056
5450 H
4122
4102
RINSING WATER HOSE CONN.
2309
P 5441
5452 GS b
4122
R404A DISCHARGE TO OUTSIDE
4127
2310
S 2105
FUEL OIL
2132
PI 4202
PC 4207
4210 2114
PC 4206
PC 4208
S
P 5451
PURGE TO OUTSIDE
2111
1502
1012
DRY INERT GAS
UPPER DECK
VENT
1506
TI PZA 4328 L 4329
STEAM LINE
4331
WATER FILLING CAP (IG036)
PI 4330
DIESEL OIL LINE SEA WATER LINE
BA230
R-404A LINE I.G. SCRUBBER P/P IG043
IG044 IG045
FRESH WATER LINE IG024 TO NEAREST E/R SCUPPER TO NEAREST E/R SCUPPER
4 - 49
AIR LINE INERT GAS LINE
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.11 Inert Gas and Dry Air Generator General The dry air/inert gas plant installed in the engine room produces dry air or inert gas which is used for the tank and piping treatments prior to and after a dry docking or an inspection period. The operating principle is based on the combustion of a low sulphur content fuel and the cleaning and drying of the exhaust gases. The inert gas plant includes an inert gas generator, a scrubbing tower unit, two combustion-air blowers, an effluent water seal, a fuel injection unit, an intermediate dryer unit (refrigeration type), a final dryer unit (adsorption type), and an instrumentation / control system. Manufacturer: Inert gas delivery rate: Dry air delivery rate: Delivery pressure: Inert gas/dry air composition Inert gas/dry air dew point: Inert gas composition (% vol)O2 : Inert gas composition CO2 : Inert gas composition CO (max): Inert gas composition NOx (max): Inert gas composition SOx (max): Nitrogen balance to 100% Inert gas composition ‘soot’ (on Bacharach scale): Temperature Dewpoint
complete absence about 30°C (Max. 65°C) Maximum -45°C after expansion to atmospheric pressure
The products of the combustion are mainly carbon dioxide, water and small quantities of oxygen, carbon monoxide, sulphur oxides and hydrogen. The nitrogen content is generally unchanged during combustion and the inert gas produced consists mainly of 86% nitrogen and 14% carbon dioxide. Initially, the hot combustion gases produced are cooled indirectly in the combustion chamber by a sea water jacket. Thereafter, cooling of the gases mainly occurs in the scrubber section of the generator where the sulphur oxides are washed out. The sea water for the inert gas generator is supplied by one of the ballast pumps via ballast main isolating valve BA230 or I.G scrubber p/p. Before the delivery out of the generator, water droplets and trapped moisture are separated from the inert gases by a demister. Further removal of water occurs in the intermediate dryer stage where the refrigeration unit cools the gas to a temperature of about 5°C. The bulk of the water in the gas condenses and is drained away with the gas leaving this stage via a demister. In the final stage, the water is removed through the absorption process in a dual vessel desiccant dryer. The desiccant dryer units work on an automatic change-over cycle where the out of line desiccant unit is first reactivated with warm dry air that has gone through the reactivation dryer system. A pressure control valve located in the outlet of the dryer unit maintains a constant pressure throughout the system, thus ensuring a stable flame at the generator. Dewpoint and oxygen content of the Inert Gas produced are permanently monitored. The oxygen level controls the ratio of the air/fuel mixture supplied to the burner. The oxygen content must be below 1% by volume and the dewpoint of -45°C. Both parameters are displayed locally and remotely through the IAS. For delivery of inert gas to the cargo system, two combined remote air-operated control valves operated through solenoid valves are fitted in the distribution system, i.e. the purge valve and the delivery valve.
The dry air/inert gas plant is started locally but operates on a full automatic control mode.
Dry-Air Production
The connection to the cargo piping system is made through two non-return valves and a spool piece that normally dismantled.
The inert gas generator can produce dry-air instead of inert gas with the same capacity for the production of dry air:
Working Principle
There is no combustion in the generator.
Inert gas is produced by the combustion of oil with air, followed by further treatment to obtain the required qualities and properties. Fuel (Diesel oil) is supplied to the combustion chamber by the fuel oil pump and air from the air blowers.
There is no measure of oxygen content.
Good combustion is essential for the production of a good quality, soot-free, low oxygen inert gas.
Burner Description Two ‘roots’ type blowers, each supplying 50% of the total capacity of the generator, supplied combustion air to the main burner. A regulating valve in the air discharge line can manually adjust its quantity. Fuel (Diesel Oil) is supplied at a constant pressure by the gas oil electric pump that has a built-in pressure overflow valve. Before ignition or start up of the unit, and with the pump running, all the fuel is pumped back via this fuel oil overflow valve that also serves to regulate the delivery pressure of the pump. The fuel oil flows to the nozzle of the main burner via two solenoid valves and two fuel oil regulating valves. A programme switch in the local control panel regulates one of the solenoid valves which also operates the pilot burner and initial firing. The main burner is ignited by a pilot burner. The main fuel oil burner is of the high pressure atomizing type. The fuel is directed to the burner orifice through tangential slots that imparts a rotation motion that ensures that the fuel leaves the burner as a thin rotating membrane that is atomized just after the nozzle. Alarms and Trip IGG. system abnormal alarm Cooling unit abnormal alarm Dryer unit abnormal alarm IGG. No.1 blower fail alarm IGG. No.2 blower fail alarm IGG. F.O. pump fail IGG. oxygen content high alarm IGG. oxygen content high-high alarm IGG. oxygen content low alarm IGG. dew point high IGG. delivery temperature high IGG. delivery pressure high IGG. flame fail Scrubber C.W. level high Scrubber inlet C.W. pressure low Scrubber outlet C.W. temperature high
The oxygen signal is overridden when the mode selector is on dry-air production. After the processes of cooling and drying and if the dewpoint is correct, the dry air is supplied to the cargo system through the delivery valve (with the purge valve closed).
* ACCOMMODATION - ALARM 30% LEL : 21 POINTS - ALARM 60% LEL : 1 POINT FOR AIR COND. ROOM - COMMON FAILURE ALARM - ALARM 30% LEL : 1 POINT - ALARM 60% LEL : 1 POINT - FAILURE ALARM : 1 POINT
DC 24 V
60% LEL (3 POINTS) : FUEL GAS MASTER VALVE CLOSE
CCR AIR COND. FAN TRIP AT 60% LEL FROM AIR INTAKE FOR AIR COND.
* ACCOMMODATION - ALARM 30% LEL : 21 POINTS - ALARM 60% LEL : 1 POINT FOR AIR COND. ROOM - FAILURE ALARM : 21 POINTS
POWER SUPPLY GAS ALARM METER
ENGINE ROOM GAS ALARM PANEL
ECR
DRAIN SEPARATOR C.C TYPE ANALYSER C.C TYPE ANALYSER
ACCOMMODATION AREA
Part 4 Cargo and Ballast System
LNGC DISHA 4.12 Fixed Gas Detection System (See Illustration 4.12a) Introduction The Gas Detection System supplied for Hull No. 2210 monitors for flammable gases within the following areas : - Cargo part - Cargo Area System - Accommodation - Engine room - Engine Fuel & IGG Outlet Each area has its individual control panel to provide local alarms and trip signals. These alarms are also transmitted to the IAS and Extension Alarm Repeater Panel. Each control panel is fitted with a power supply change-over unit that provides an automatic change over to the stand-by in the event of a main power supply failure. Equipment The complete Gas Detection System installation comprises the following equipment : 1) Cargo Part Sampling System, including : • BH20 Tankscan, sampling control panel • Power Supply Change-over Unit • Stop Valve Box • Vent Tank Moisture Separator 2) Cargo Area System • TQ 8100 Control Panel 3) Accommodation System • TQ 8100 Control Panel 4) Engine Room System • TQ 8100 Control Panel 5) Engine Fuel and IGG Outlet System • TQ 8100 Control Panel 6) MCU Terminal and Extension Alarm Repeater Panel 7) Extension alarm repeater panels. The main Cargo Part System control panel is based around the BH20 Tankscan sampling system. Sampling from 22 sample points and passing the sampled gas over a GD129 Infrared gas analyzer. Sampling sequence is controlled automatically by individual solenoid selection valves. The sample gas is drawn into the panel via internal sample pumps. In addition, the BH20 System is equipped with Duty and Stand-by sample pumps and gas analysers. Both are controlled by a single changeover key-switch, that divert the sample flow through the system and the electrical signals to the control unit to provide an immediate line backup should either unit fails.
Cargo Operating Manual A power supply change-over box, supplies the panel with a 220V, 60Hz power, and automatically changing over to the ship’s secondary supply should the main supply be interrupted. This unit also monitors the main control panel and removes the supply when an internal gas leak is detected.
For further information on the GD129 Infrared analyzer and TQ120 catalytic Flammable sensors.
The Stop Valve Box is used to isolate individual sample lines, if required and also houses in-line filters. An internal catch pot is included in line 1 (vent tank) as a shut off mechanism should line 1 becomes waterlogged.
The Gas Detection System is 2 types:
The Gas Vent Drain Tank Moisture Separator Box, houses an internal coalescing filter, to extract moisture from the sample gas. Also included are drain and shut off valves. The Extension alarm panel accepts an RS485 communication signal from the BH20 sampling system and displays concentration alarms via an external monitor, should any sample line record gas concentration above 30% LEL. Also included in the monitor display are system fault and communication fault alarms from the BH20 system. Alarm levels are set by the BH20 control unit and then reported to the extension alarm panel. The Extension alarm panel also displays concentration and system fault alarms from the other Point Detector monitoring systems covering the Accommodation, Engine Room, and Engine Fuel & IGG Outlet section. Alarms generated from the point detector systems are digital inputs from normally closed, volt free contacts within the individual systems. Again alarm levels are set to the individual control systems. IAS Alarms. Gas Concentration and sample location are reported to the IAS from the Master Control Unit (MCU). The TQ8100 units monitor the areas that include the Accommodation, Engine Room and Engine Fuel & IGG Outlet part. TQ8100 is a point detection system where either an infrared or catalytic detector present in the areas that are continuously monitored and controlled via the TQ8100 respective control cabinet. The TQ8100 unit capable of monitoring/controlling up to thirty two (32) points continuously and instantaneously and can be assigned number of locations. Control Systems Area Monitored
Control Panel
No. of channels
Detector Type
Display Range
Alarm Set Point
Cargo Part
BH20
22
IR
See Note
See Note
Cargo Area
TQ8100
4
CC
0∼100% LEL
30∼60% LEL
Accommodation
TQ8100
22
CC
0∼100% LEL
30∼60% LEL
Engine Room
TQ8100
8
CC
0∼100% LEL
30∼60% LEL
Engine Fuel & IGG Outlet
TQ8100
6
IR
0∼100% LEL
30∼60% LEL
Operation
- The BH20 Tankscan Aspirated System - TQ8100 Fixed Point Monitoring System The BH20 has 22 sample points on the cargo part system connected through a stop valve box. This unit sequentially samples the level of flammable gas using a GD129 infrared sensor. The BH20 also contains an internal gas sensor to detect flammable gas level inside the enclosure. The system is connected to a power supply change over unit which can keep the system powered on a stand-by supply if there is an interruption in the mains power supply. Included in the Cargo Part system is an Extension Alarm Panel. This is situated in the fire control room to provide status of all monitored gas detectors. The cargo part Sampling system has an additional 4-20mA signal to indicate the sample line number selected. - BH20 - GD129 - Power supply change over unit The TQ8100 is 32 Point Monitoring System capable of accepting inputs from either three wire, or two wire 4∼20mA detectors and transducers, fitted in the : - Cargo Area - Accommodation Part - Engine Room - Engine Fuel Gas & IGG Outlet These systems monitor both Infrared and Catalytic Bead Sensors to detect flammable gas, and generate alarms in the IAS through the MCU and Extension alarm Panel. For further detailed information on the above please refer to : - GD129 - TQ120 - TQ8100 Each gas detection panel alarms locally and reports to the IAS through the MCU. Signals for gas concentration and normally closed volt free alarm contacts for fault condition are generated in the individual panel. Alarm conditions are forwarded to the TQ Master Control Unit (MCU) which then forwards all alarms on fault conditions to the IAS.
Note : Primary insulation spaces range 0∼100% vol, alarm 30% vol, others range 0∼100% LEL, alarm 30% LEL.
4 - 52
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.12b Gas Detection System
Repeater Panel (In FCR)
Repeater Panel (In ECR)
Repeater Panel (In W/H)
E/R Sys Control Panel For CC Type
IAS
Bosun Store
Trunk Deck Space No.4
E/R Sys Control Panel For IR Type
MCU
MCU Terminal Unit
Trunk Deck Space No.3
Trunk Deck Space No.2
Trunk Deck Space No.1
C.C. Type Bosun Store
Vent Exhaust Form Pipe Duct Liquid Dome
C/L Vent Mast
Vent Mast
Liquid Dome
Liquid Dome
Vent Intake To Pipe Duct
Vent Mast
Liquid Dome
FWD P/RM
Accom. Sys Control Panel
Primary Insul. Space
Cargo Area System Control Panel for IR Type
Motor Comp. Room Room
Primary Insul. Space
Sampling Plug
Primary Insul. Space
Secondary Insul. Space
Secondary Insul. Space
C.C. Type Bosun Store
Primary Insul. Space
Secondary Insul. Space
C.C. Type Bosun Store
B.TH. RM C.C. Type Bosun Store
Secondary Insul. Space
C/L
Cargo Area System Control Panel for CC Type
For Cargo Comp. Room For Electric Motor Room Primary Insul. Space Secondary Insul. Space Cargo Escape Tank
Trunk Deck Space
ay
Upper Deck
CL
swa
y
Si de
s-
wa y
Pa s
-w
Pa s
Upper Deck
Si de
swa
y
Si de
Pa s
Pa ss
Si de
Upper Deck
Trunk Deck Space
Si de
Si de
Pa s
swa
y
Trunk Deck Space
Valve & Tee For P.D. Trunk To Be Installed Inside Passage Way
CL
Pa s
s-
wa y
CL TRUNK DECK
DETAIL OF EXHAUST FROM ANALYSER CABINET UPPER DECK C.C. Type
ACCOM. OUTSIDE
MAIN PANEL (IN CCR)
15
C.C. Type
VENT INTAKE
STOP V/V BOX
VENT EXHAUST
END COVER WITH MESH SHALL BE PROVIDED.
Pa ss
-w ay
CA RG O
Si de
Upper Deck
Si de
TO BE LOCATED AT HAZARDOUS AREA TO BE LOCATED IN AN ACCESSIBLE PLACE WITH VERY LITTLE TRANSIT OF PEOPLE. GD001
STOP V/V BOX ACCOM. FRONT SIDE
FWD P/P RM
C.C. Type
C.C. Type
NO .1
GAS DETECTION MAIN LINE
Pa s
swa y
Trunk Deck Space
TK
BOSUN STORE
CL
S/C
B.T. RM PIPE DUCT
4 - 53
F.P TK
Part 4 Cargo and Ballast System
LNGC DISHA Cargo Area System (IR Type) Sample order Location 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
No.1 Cargo tank primary insulation space No.2 Cargo tank primary insulation space No.3 Cargo tank primary insulation space No.4 Cargo tank primary insulation space No.1 Cargo tank secondary insulation space No.2 Cargo tank secondary insulation space No.3 Cargo tank secondary insulation space No.4 Cargo tank secondary insulation space No.1 Cargo tank vent mast No.2 Cargo tank vent mast No.3 Cargo tank vent mast No.4 cargo tank vent mast Side passage way starboard forward Side passage way starboard aft Side passage way port forward Side passage way port aft Vent intake to pipe duct Vent exhaust from pipe duct Cargo compressor room (1) Cargo compressor room (2) Cargo motor room Cargo escape tank
Cargo Operating Manual Boil-off Gas Pipe Duct (IR Type) Sample point Location 1 2 3 4 5 6
No. 1 boiler fuel gas double pipe No. 2 boiler fuel gas double pipe Gas hood room Inert gas line after dryer Engine room supply fan duct starboard fwd Engine room supply fan duct port fwd
Cargo Area (CC Type) Sample point Location 1 2 3 4
Bosun store starboard Bosun store port Bow thrust room Forward pump room
4 - 54
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.12c Gas Detection System TRUNK DECK
A DECK
UPPER DECK
RESCUE BOAT IN LOBBY (TYPICAL, P&S, UPP/A-DK) CANAL BOATMAN REPAIRER
Elevator lift mach. room Wheelhouse Entrance on D deck port Entrance on D deck starboard Entrance on CCR deck (C deck) port Entrance on CCR deck (C deck) starboard CCR Gas detection panel Entrance for air conditioning room Fire control room Entrance on B deck port fwd Entrance on B deck starboard fwd Entrance on B deck port aft Entrance on B deck starboard aft Deck office Entrance on A deck port Entrance on A deck starboard Dry provision handling area Gally Main entrance to Accomm. Upper deck port Main entrance to Accomm. Upper deck starboard Fresh air duct in air conditioning mach. room
4 - 56
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.13.1a Cargo Valve Hydraulic Lines
MANIFOLD(P)
(CL302)
(CL301)
(CL401)
(CL402)
(CL405)
(CL400) (CL410)
(CG601)
(CG602)
(CL803)
(CL804) (CL300)
(CG801)
(CL801)
(CL802)
(CL310)
(CS304)
(CS301)
(CL101)
(CL102) (CL100)
(CL200)
(CS305)
(CS306)
(CS307)
(CS405)
(CS406)
(CP178)
(CL305) (CS101)
(CS401) (CS404)
(CL110)
(CL210)
(CS104)
(CL105) (CG106)
(CS407) (CS201)
(CG002)
(CS204)
(CL205)
(CL201)
(CL202)
(CG001) (CS107) (CS207)
(CS206)
(CS106)
(CS105)
(CG105)
(CS205)
(CG405) SIDE PASSAGE
NO.4 SOL. V/V BOX (WD053) (WD051) (WD052)
HYD. POWER PACK ROOM
NO.3 SOL. V/V BOX
NO.8 SOL. V/V BOX
(WD047) (WD045) (WD046)
NO.2 SOL. V/V BOX
NO.1 SOL. V/V BOX (WD035) (WD033) (WD034)
(WD041) (WD039) (WD040)
(VR001) Ball valve
(VR005) (VR004)
HYD. POWER PACK WITH 2 X ACCUM. STAND AND 2 X N2 SPARE BOTTLES
TRUNK DECK
(WD049)
(OIL TANK : 1000 L)
OIL COAMING
TRUNK DECK
(WD050)
(VR003)
TRUNK DECK
(WD037)
(WD043)
(WD048)
(WD044)
TRUNK DECK
(WD038)
(WD042)
(WD031)
(WD036)
(WD032)
(WD030)
(VR002)
NO.7 SOL. V/V BOX TO/FROM POWER UNIT (FOR BALLAST)
SIDE PASSAGE
NO.5 SOL. V/V BOX
(CS504)
(CG522)
MANIFOLD(S)
(CS501) (CG501)
(CG505)
(CG517)
(CG513)
(CG509)
CARGO COMPRESSOR RM.
(CL704)
4 - 57
(CL703)
(CG701)
(CL702)
(CL701)
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.13 Cargo & Ballast Valve Control System 4.13.1 Cargo Valve Control System General The system is applied for remote control of valves and actuators designed primarily for use on board ships as shown on the attached hydraulic schematic diagram and valve lists. The remote valves are provided with hydraulic actuators powered form hydraulic power unit and controlled by electro-hydraulic solenoid valves. All remote valve actuators are designed to be capable of local manual operation. The danfoss position indicator for the valve open / shut position is designed to indicate the position of hydraulically actuated valves. In general, the valve position is indicated by the limit switch(RLS) or potentiometer(CPI) mounted directly on the valve, respectively. All the valves necessary for the operation of the cargo and ballast system are hydraulically operated by separate hydraulic power packs, situated in the hydraulic power pack room, engine casing 'B' deck forward. Control of the power packs and valve operation is from the IAS, touch screen and key board situated in the CCR. Cargo System The hydraulic power unit consists of two main pumps and one topping-up pump. During normal loading and unloading operations, only one pump is required to meet the demand, while the second pump is put on automatic standby mode that is ready to cut in when the system pressure is reduced to 11 MPag. The topping up pump is normally used when the vessel is in sea mode condition. All remotely operated valves are piston operated, except for the liquid dome and the spray header isolating valves that are vain type actuators. The supply oil is distributed to 6 solenoid valve cabinets situated at the side passageway (port and starboard) and 1 in the cargo compressor room. Each cargo tank, manifold area, cargo compressor room and the master BOG station has its respective solenoid cabinet as follows: No.1 Solenoid Valve Box (16 Units) Valves CL101, 102, 105, CS101, 104, 105 Valves CS106, 107 Valve CP178 Valves CG105 Valves CG106, CL100, 110 Valves WD033, 034, 035
No.7 Solenoid cabinet feeds starboard manifold (ESDS) and ballast system Valves CL701, 702, 703, 704, CG701 ESD ON/OFF Butterfly valve Valves WD030, 031, 032, 036, 037, 038 ON/OFF Butterfly valve No.8 Solenoid cabinet feeds port manifold (ESDS) Valves CL801, 802, 803, 804, CG801 ESD ON/OFF Butterfly valve Accumulator for ESD Valve Accumulators have two times of a capacity required for closing the emergency shut-down valves on one side of the manifold simultaneously within 30 seconds at ambient temperature of about 15°C. 1 set of fuel gas master valve and 10 sets of manifold valves are designed to automatically close the emergency shut-down valves at the manifold area. The fuel gas master shut-off valve by the pressurized oil in independent hydraulic accumulator with the emergency shutdown hydraulic pilot valve hydraulically operating cylinder 3/2way. Hydraulic Power Unit System working pressure : 10.5 MPag Oil tank:1000 L
One main motor / pump unit is operated as in a “service”, and the other is operated as a “stand-by”. One topping up motor / pump unit is designed to maintain the system pressure when no valve operation is required. Accumulators are installed for oil leakage compensation through the direction control valve. Two(2) spare N2 gas bottles are provided each having capacity of abt. 45liters. Pressure switches control the pump cut in / cut out, with low oil pressure alarm and pump failure alarms transmitted to the IAS. The oil level in the tank is monitored by a low level alarm switch. Pump Settings Pump start Pump stop Stand-by pump cut in High pressure alarm Low pressure alarm ESDS operating pressure High temperature alarm Return filter clogging alarm Pressure filter clogging alarm
Emergency Operation When hydraulic pressure cannot be obtained due to trouble of hydraulic pump unit by some reason, each valve can be operated by spanner or portable hand pump prepared for emergency. In case of electric power failure between the control area and solenoid valve area, the solenoid valve can be operated manually (finger operation). In case of hydraulic power loss between the solenoid valve area and actuator, the actuator is operated manually by means of a spanner or hand pump. Emergency Hand Pump Operation All the hydraulic piston type operating valves have an emergency hand pump connection. There are three portable emergency hand pump units, one available in the engine room, one in the pipe duct space and one in the deck store. The isolating valves on the distribution block are first shut off and the hoses of the emergency hand pump fitted to the snap-on connectors. Control of direction is via a hand operated changeover control block.
The hydraulic power unit is designed as a hydraulic source for the open / close operation of the hydraulic valve. The power unit has a tank as its basic unit, and consists of two(2) electro-hydraulic main motor / pump units, and one(1) electrohydraulic topping up motor / pump unit, firmly mounted on the top cover of the tank.
SOL.V/V BOARD FOR BALLAST,BILGE,F.O. S.W.COOLING SYS WATER SPRAY SYS.
(CW10) (CW14) (BA229)
(BA226) (OF14)
(OF13)
(OF48)
(BA214)
(ES191)
(BA227)
(OF10)
(ES196)
(BA215)
(BA211)
(BA212) (BA222) (BA202) (BA209)
(CW26)
(BA207) (BA208)
(BA210)
(CW25) (CW101)
(CW102)
(CW103)
(BA201) (BA203) (BA205) (BA206)
4 - 59
Part 4 Cargo and Ballast System
LNGC DISHA 4.13.2 Ballast Valve Control System General The system is applied for remote control of valves and actuators, designed primarily for use on board ships as shown in the attached hydraulic schematic diagram and valve lists. The remote valves are provided with hydraulic actuators powered from hydraulic power unit and controlled by electro-hydraulic solenoid valves. All remote valve actuators are designed to be capable of local manual operation. The danfoss position indicator for the valve open / shut position is designed to indicate the position of the hydraulically actuated valves. In general, the valve position indication is obtained from the limit switch(RLS) or potentiometer(CPI) mounted directly on the valve, respectively. Ballast, Bilge, F.O. Sea Water Cooling and Water Spray Systems The hydraulic power unit consists of two main pumps and one topping-up pump. During normal loading and unloading operations, only one pump is required to meet the demand, while the second pump is put on automatic standby mode ready to cut in when the system pressure is reduced to 11 MPag. The topping up pump is normally used when the vessel is in sea mode condition. All remotely operated valves are piston operated. The supply oil is distributed to 1 solenoid valve board situated in the engine room. The operation of the valves is conducted from the IAS in the CCR. Hydraulic Power Unit System working pressure : 10.5 MPag Oil tank:1000 L The hydraulic power unit is designed as a hydraulic source for the open / close operation of the hydraulic valve. The power unit has a tank as its basic unit, and consists of two(2) electro-hydraulic main motor / pump units, and one(1) electrohydraulic topping up motor / pump unit, firmly mounted on the top cover of the tank. One main motor / pump unit is operated as in a “service”, and the other is operated as a “stand-by”. One topping up motor / pump unit is designed to maintain the system pressure when no valve operation is required. Accumulators are installed for oil leakage compensation through the direction control valve. Two(2) spare N2 gas bottles are provided each having a capacity of abt. 45liters.
Cargo Operating Manual Pump Settings Pump start Pump stop Standby pump cut in High pressure alarm Low pressure alarm ESDS operating pressure High temperature alarm Return filter clogging alarm Pressure filter clogging alarm
The hydraulic system can be used as a emergency back up supply to the main cargo valve system, by opening isolating cross connecting valves that must be kept shut during normal use. Emergency Operation When hydraulic pressure cannot be obtained due to trouble of whatever reason in the hydraulic pump unit, each valve can be operated by spanner or portable hand pump prepared for emergency. In case of electric power failure between the control area and solenoid valve area, the solenoid valve can be operated manually (finger operation). In case of hydraulic power loss between the solenoid valve area and actuator, the actuator is operated manually by means of a spanner or hand pump. Emergency Hand Pump Operation All the hydraulic piston type operating valves have an emergency hand pump connection. There are three portable emergency hand pump units, one available in the engine room, one in the pipe duct space and one in the deck store. The isolating valves on the distribution block are first shut off and the hoses of the emergency hand pump fitted to the snap-on connectors. Control of direction is via a hand operated changeover control block. 2-line system
1) y
Opening of valve: - Close the stop valves on the control block mounted on the actuator. - Connect the hoses “B” and “A” to the emergency control block (e.g. HSblock) mounted on the actuator. - Turn the pilot valve on the hand pump to “open” position and continue pumping until the actuator/valve is open (see the visual indicator on the actuator or pressure gauge for the nominal working pressure of 10.5 (13.5)MPag). - The valve is prevented from closing when the pilot valve is placed in centre position.
y
Closing of valve: - Turn the pilot valve on the hand pump to the “close” position.
Pressure switches control the pump cut in / cut out, with the low oil pressure alarm and pump failure alarms transmitted to the IAS. The oil level in the tank is monitored by a low level alarm switch.
4 - 60
Open = AÆ T, P Æ B Close = BÆ T, P Æ A
1-line system
2) y
Opening of valve: Only hose “B” is used.
y
Closing of valve: Turn the pilot valve on the hand pump to the “close” position. The actuator / valve closes without pumping.
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.14.1a Cargo Tank Relief Valve
Illustration 4.14.2a Primary and Secondary Insulation Space Relief Valves
Specifications Quantity Type Set pressure Reseating pressure Required capacity Relieving capacity
Specifications Quantity Type Set pressure Reseating pressure Required capacity Relieving capacity
9 Set Pilot Operation 25 kPag 22 kPag 22000 Nm3/h 28550 Nm3/h
17 Set Pilot Operation 1.0 kPag 0.8 kPag 1400 Nm3/h 2087 Nm3/h
Test gag Test gag
Exhaust tube
Adjust screw
Adjust screw
Pilot Valve Vent Tube Diaphragm
Check plate Diaphragm
Check plate
For test Connection RC 1/2
Pilot Valve
For manual lifting device connection Rc1/2
Diaphragm retainer Diaphragm
For test Connection RC 1/2
Exhaust Tube For manual lifting device connection Rc1/2
Diaphragm retainer Set plate
Supply Pipe
Supply pipe
Nozzle
Nozzle
4 - 61
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.14 Relief Systems
4.14.2 Primary and Secondary Insulation Space Relief Valves
4.14.3 Line Relief Valves
(See Illustration 4.14.2a) General Description Each cargo tank is fitted with two pressure / vacuum relief valves required by the IGC code. The primary and secondary insulation spaces are each protected by two pressure-relief valves per cargo tank. The valves are manufactured by Fukui Seisakusho Co., Ltd. and are designed specifically to work on marine-based LNG systems.
4.14.1 Cargo Tank Relief Valves
Manufacturer: Type: Number of units: Number per tank Primary Insulation Space: Secondary Insulation Space: Set Pressure: Reseating Pressure: Flow rate per valve:
Each section of the cargo pipe work, except the vapour line that can be isolated by the two valves, is fitted with an over pressure relief valve fitted. The cargo manifold relief lines, the cargo machinery space relief lines and No.3 & 4 cargo tanks relief lines are led to No.3 and 4 vapour domes. No.1 and 2 cargo tanks relief lines are led to No.1 and 2 vapour domes. In order to operate manually lift the lever. Illustration 4.14.3a Cargo Line Relief Valve Test gag
(See Illustration 4.14.1a) Manufacturer: Type: Number of units: Number per tank: Set Pressure: Reseating Pressure: Flow rate per valve: Vacuum Relieving:
The cargo tank relief valves are fitted at the vapour domes of each tank and vent to their associated vent mast riser. The relief valves are of the PORV (pilot operated relief valve)-type. A cargo tank’s pressure sensing line relays the pressure directly to the pilot operating the valve. This manner assures that an accurate operation at low pressure prevails inside the tank. The cargo relief valves are set up initially by the manufacturers based on the requirements of the ship. If overhaul of the valves by the ship’s staff is carried out, the valves must be checked and reset to the original settings. It is extremely important that the vent mast is checked on a regular basis and drained of any accumulated water. The purpose of which is to ensure that the relief valves operate at their correct settings that would otherwise be altered if water is to accumulate in the vent mast and flow into the valve assembly.
Four-PORV relief valves per cargo tank protect the primary and secondary insulation spaces.
Lifting fork
A gas detection line leads out from below the valves. One line points from the primary insulation space and the other from the secondary insulation space per each tank to the gas monitoring system, to give a constant indication of the atmosphere inside the primary and secondary insulation spaces.
Adj. screw lock nut Adjusting screw
The primary insulation relief valve vapour outlet leads to a separate vent line that runs alongside the associated vent mast. This is to prevent any counter pressure or back flow from the main vent mast should the cargo tank’s relief valves is lifted from the nitrogen snuffing system.
S
Lever
It is extremely important that the vent line is checked on a regular basis and drained of any accumulated water. This is to ensure that the relief valves operate within their correct settings that could otherwise be altered if water is to accumulate in the vent mast and flow into the valve assembly. The secondary insulation space’s relief valves vent directly to the deck via a downward facing tail pipe. It is not necessary for these to be led to the vent mast as the likelihood of LNG vapour in the insulation space is very remote.
Disc Adj. ring
The primary and secondary insulation spaces valves are set up initially by the manufacturer base on the requirements of the ship. If an overhaul of the valves by ship’s staff is carried out, the valves must be checked and reset to their original settings.
S
Adj. lock bolt
Nozzle
4 - 62
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.15.1a Ballast Piping
.4 NO
S.C
To Atmos Cond.
(P) TK . B W. W.
(P) . TK W.B DB. 4 . NO
BA202
To Main Cond.
. NO
.W 3W
T .B.
) K(P .2 NO
(P) . TK W.B DB. 3 . NO
(P) TK . B W. W.
(P) . TK W.B DB. 2 . NO
.1 NO
(P) . TK B . W.W
B. T . W. 1 DB NO.
(BA501/BA502)
IN BOSUN STORE (WATER TIGHT DECK) .B. TK (P )
) (P TK
) K(P
EP W
R
. .B
DE
E/
W
BA222
BA006
FW D
BA228
BA212
BA220
NO. 2 B.P BA229
BA219
*
TO I.G.G. SYS
STEEL PIPE
STAND-BY B.P
BA226 BA217
*
BA206
PIPE DUCT
BA209
BA218
BA208
BA007
B.T. RM BA003
BA034
BALLAST MAIN
*
BA036
NO. 1 B.P
BA002
BA215
TK (S)
BA203
NO BA214
.B B. W .4 D
(S) . TK NO
.B B. W .3 D
(S) . TK NO
.B B. W .2 D
(S) . TK
(S) . TK W.B . B D NO.1
BA201 BA231
B.S TRIP. EDUCTOR BA225
F.P. TK
BA205
BA207
BA216
BA001
BA004
S.C
BA213
From Water Spray Pump
From IG Main for Gas Freeing of Ballast Tanks
E/R
. B. W
) (S TK
FLANGE ADAPTER
.4 NO
B. W. W.
(S) TK .3 NO
*
Spool Piece
W.
T B. W.
) K(S .2 NO
B. W. W.
(S) TK .1 NO
W
T .B. .W
) K(S
W. B.
BA230
*
EM'CY BILGE SUCTION BA210
BA227
BA005
BA035
BALLAST MAIN
DE EP
A.P. TK
SLEEVE DOUBLE O-RING
BA211
FW D
BA221
MARKED VALVES SHALL HAVE THE FUNCTIONS OF THROTTLING AND FULL POSITIONING INDICATION.
Pipe Duct Spool Piece
4 - 63
Part 4 Cargo and Ballast System
LNGC DISHA 4.15 Ballast Piping System 4.15.1 General Description
Cargo Operating Manual The driving water for ballast stripping eductor is from water spray pump. All ballast pipes in the pipe duct are of GRP with galvanized steel bulkhead pieces and pipes in ballast tank are steel painted with suction bell mouths.
System Capacities and Ratings.
Eight (8) spectacle flanges are provided for wing water ballast tank suction line in order to prevent silty water entry other tank in case of valve failure.
Ballast pumps Manufacturer: Type: Model: Rating:
Ballast piping for No.3 double bottom water ballast tank can be used for flow through method of cleaning. For this purpose, additional pipe line installed inside ballast tank.
Three ballast pumps are electric motor driven. Make: Nishishiba Electric Co., Ltd. Type: Three phase induction motor Speed: 1180 rpm Power: 330 kW Volt: 6600 V Amp: 36.5 Amp Ballast stripping eductor Rating: 300 m3/h Driving water shall be supplied by water spray pump. The ballast spaces beneath and around the outboard side of the cargo tanks are used as ballast tanks to optimize draft, trim and heel during various load conditions of the vessel. The ballast is carried during the return passage to the loading port, when only sufficient gas is carried to maintain the tanks and their insulation at cryogenic temperatures. The ballast spaces are divided into 16 tanks that are the port and starboard. In addition, the fore-peak water ballast tank, deep water ballast tank (port and starboard), and after peak tank are also used to carry ballast when required. There are also two small ballast tanks in the engine room that are used to control total ballast capacity of 52,428 m3, approximately 53,738 tonnes when filled with sea water. Three, 3,000 m3/h, vertical centrifugal pumps are fitted to enable the total ballast capacity to be discharged or loaded in approximately 12 hours for ballasting or deballasting. During cargo loading and unloading two (2) sets of the ballast pumps are used. During ballast water exchange, one (1) set of the ballast pump is used. The pumps are driven by electric motors and are located in the engine room floor, starboard side forward. The 600 mm fore and aft ballast main runs through the pipe duct with tank valves mounted on the tank’s bulkheads. This is connected to the stripping eductor. The ballast pumps fill and empty the tanks via the port and starboard side 600 mm main. One eductor placed on starboard is fitted for stripping and final educting of the tanks, with its own discharge valve.
All valves are hydraulically operated butterfly valves. The tank’s after main suctions, pump discharge valves and etc, as indicated with * on the above drawing are of the intermediate position controlled type. They are mounted at the forward end and bottom platform of the engine room. These pumps take their suction from the sea, with the high sea suction being on the port side and the low sea suction being on the starboard side. The latter being the normal operation when loading ballast. When discharging ballast they take their suction from the main ballast crossover. There is one ballast eductor, rated at 300 m3/h. The ballast pumps are used to supply sea water to the inert gas system. System Control The ballast system is controlled entirely from the CCR using the IAS in conjunction with the ballast mimic. The ballast pumps are started and stopped using the mimic, provided that the switches on the local control panel are set to remote. The pumps have an auto stop sequence control for low and high tank status. When on local control, the pumps can be started and stopped from the local control panel regardless of the position of the local/remote switch. The local control panels always take priority and can take control from the CCR at any time. All hydraulically operated valves in the system are also operated using the on screen menu/keyboard in conjunction with the ballast mimic. Two basic types of valves are fitted: those that can be positioned at the fully closed or fully opened position and those that can be positioned at any point between the fully opened and the fully closed position. The position of all valves is shown on the mimic. Provision is made for the use of a portable hand pump to operate each valve in the event of hydraulic accumulator failure. The pump discharge valves, and tank after main suction valves are multi-positional. All other valves are either open or closed. In addition to being operable from the CCR, the valves can also be operated from the solenoid valve station using the push buttons on the individual solenoids. The on screen ballast menu also shows when the pumps are switched to remote, the pump’s suction and discharge pressure, the position of the manually operated valves and the level in each tank, in terms of innage.
4 - 64
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.15.2 Ballast Water Management (Ballast Exchange)
Ballasting Scenario
Introduction
Pre-Ballast ing
A
F
The ballast water management is focused on to minimize the introduction of unwanted organisms from the discharge of ballast water in their local jurisdictions and the pollution of ballast tanks from sediment (i.e. mud). This study is provided to introduce DSME’s proposal for discussing about the method based on safety and automation. The Ballast Water Management shall consist of the Ballast Exchanging and the Ballast Tank Flushing
Deballasting A
Ballasting
F
A Unloading Port
Loading Port
main fire line
#4
F
#1
Empty WBT A
Clean WBT Silty WBT
- Pre-Ballasting: To minimize the number of silty WBT, DB WBTs shall be filled with clean seawater before arriving at the unloading port. This procedure not include in auto sequence.
No.1 stringer
Wing tank
CARGO No.2 stringer
F
Ballast Exchange
- Ballast Exchange: After departure from the unloading port, all dirty water in silty WWBT shall be exchanged with clean seawater. Simultaneous ballast water exchanging, the seawater spraying shall be carried out to clean up in ballast tanks. - For the detail schedule of ballasting/deballasting, please refer to following “Estimated Operating Time”.
Water jet nozzle
Sediment No.3 stringer Ballast line
D/B water tank Pipe arrangement of Water Set System
4 - 65
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual The Hierarchy of the Ballast Water Management
Line-Up & check Level Monitoring & Synch. TK Group: 1P/3S,1S/3P,2P/4S,2S/4P Water Spray Control Sequence Line-Up & check Spray Schedule Spray Valve Control
No.4 WWBT(P)
Estimated Operating Time Tank No.
Ballast Water Exchange Sequence
3
Capacity(m ) 2 F
3 F
Water Spray Pump Control Sequence Line-Up & check Pump Start/Stop
DB WBT Dilution Control Sequence
Ballast exchange condition 4 5 6 7 F F F F
No.1 W.W.B.T(S)
3,863
1 F
8 E
9 F
No.1 W.W.B.T(P)
3,863
F
F
F
F
F
E
F
F
F
No.2 W.W.B.T(S)
2,375
F
F
F
E
F
F
F
F
F
No.2 W.W.B.T(P)
2,375
F
E
F
F
F
F
F
F
F
No.3 W.W.B.T(S)
2,376
F
F
F
F
F
E
F
F
F
No.3 W.W.B.T(P)
2,376
F
F
F
F
F
F
F
E
F
No.4 W.W.B.T(S)
2,099
F
E
F
F
F
F
F
F
F
No.4 W.W.B.T(P)
2,099
F
F
F
E
F
F
F
F
F
Time[h]
9.38[Total]
-
1.1
0.93
1.1
0.93
1.5
1.4
1.4
1.3
Line-Up & check Level Monitoring & Synch.
Estimated ballast pump efficiency during pumping(2×3,000m3):approx. 80% of nominal capacity W.W.B.T. - Sequential Method (Empty-Refill) The sequential method entails completely emptying ballast tanks and refilling with open-ocean water. Emptying of certain tanks may lead to significantly reduced stability, higher stresses, high sloshing pressures, and/or reduced forward drafts. A secondary effect of reduced forward draft would be an increased probability of bow slamming. The primary considerations in assessing sequential exchange scenarios should focus on vessel stability, hull girder strength, propeller immersion, bridge visibility, and list angle.
4 - 66
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.15.1b Silty Water Treatment System
NO.3 W.W.B TK (P)
NO.2 W.W.B TK (P)
NO.1 W.W.B TK (P)
NO.4 DB.W.B. TK (P)
NO.3 DB.W.B. TK (P)
NO.2 DB.W.B. TK (P)
NO.1 DB.W.B. TK (P)
TYP IC
AL
NO.4 W.W.B TK (P)
PIPE DUCT
FRAME OR BHD ABT. 700
ABT. 2140 OR ABT. 1400
STR. OR DK
FIRE MAIN
TRUNK DK K SPA TRUNK D
FIRE MAIN
CE
L
NO.1 W.W.B TK (S)
K .T .B .W W
:S PO TPE LY 37 0 (T M YP IL D IC ST AL EE )
) (P
W .W
UPPER DK .B .T
K
(S )
DA M FF ER CO
NO.2 W.W.B TK (S)
NO.1 DB.W.B. TK (S)
6.0, BRONZE)
AT 'L
NO.3 W.W.B TK (S)
NO.2 DB.W.B. TK (S)
NOZZLE (ORIFICE : (TYPICAL)
M
NO.4 W.W.B TK (S)
NO.3 DB.W.B. TK (S)
ABT. 700
PI PE
NO.4 DB.W.B. TK (S)
FRAME OR BHD ABT. 1400
B.W
D/B W.B. TK (P)
4 - 67
D/B W.B. TK (S)
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
ABNORMAL STOP CONDITION 3
START
1
SEQ START/STOP SWITCH = "START" Y 2
VALVE SYNC
ABNORMAL STOP CONDITION
FINISH REQUEST FROM BALLAST EXCHANGE TANK SEQ
N
(CONTROL FROM BALLAST EXCHANGE TANK SEQUENCE)
SPRAY MODE ASYNC OR SYNC
VALVE ASYNC
N TK LEVEL ≤ L1O + a
*1
Y
*1
Y
START WATER SPRAY PUMP SEQ
2
Y
N TK LEVEL ≤ L1O + a
N
- SEQUENCE STOP REQUEST - TANK LEVEL BAD PV - WATER SPRAY V FB ALARM - WATER SPRAY V UNC ALARM - WATER SPRAY V FAIL LIST - WATER SPRAY PUMP SEQ ABNORMAL
CLOSE NO.1 SPRAY VALVE
*A1
CLOSE NO.2 SPRAY VALVE CLOSE NO.3 SPRAY VALVE
START WATER SPRAY PUMP SEQ
WATER SPRAY PUMP SEQ STOPPED
N
Y
TK LEVEL ≤ L1O
Y
TK L1C ≤ LEVEL ≤ L1O *1
*1
*2 OPEN NO.1 SPRAY VALVE
N
*2 OPEN NO.1 SPRAY VALVE
STOP SEQ START/STOP SW ITCH
*2
CLOSE NO.1 SPRAY VALVE 3
OPEN NO.2 SPRAY VALVE OPEN NO.3 SPRAY VALVE
Y
TK L2C ≤ LEVEL ≤ L2O *1 N
*2 OPEN NO.2 SPRAY VALVE
END
*2
CLOSE NO.2 SPRAY VALVE
OVER LAPPING TIME (ABOUT 1 min)
LEVEL L1O NO.1 STRINGER
Y
TK LEVEL ≤ L3O
*2 OPEN NO.3 SPRAY VALVE
L2O
*1 N
L1C NO.2 STRINGER
*2
L3O
CLOSE NO.3 SPRAY VALVE
L2C NO.3 STRINGER
SPRV1
SPRV2
SPRV3
TIME
WHEN THIS SEQUENCE IS STOPPED BY ABNORMAL STOP CONDITION, “WATER SPRAY PUMP SEQUENCE STOP” IS REQUESTED.
1
*1 TIME DELAY (10 SEC) IS APPLIED *2 THIS PROCESSING IS DONE ONE TIME ONLY AT DETECTING THE LEVEL CONDITION
4 - 68
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
Illustration 4.15.1c Bilge and Deck Scupper System
BSD1/D2/D3/D4 ONLY MOOR'G DK ABT.500
UPPER DECK
15
FROM FIRE MAIN
UPPER DECK
30
SID
E
SH
EL L
FROM FIRE MAIN
SIDE-PASSAGE
65A BS315
BS314
BS304
FROM HFO TRANS. P/P
BS303
BS605
FROM FIRE MAIN
UPPER DECK
BS601
BILGE HAT (P & S) SEE DETAIL
TK
C.L
BS008
BILGE HAT(P & S) SEE DETAIL
BS001
S.L.W.L
S.L.W.L
B.W BS002
FWD P/P RM
NO .1
NO .2
NO .4
CA RG O
TK CA RG O
TK CA RG O
DIST. W TK
NO .3
W.B
CA RG O
. TK
(P
TK
&S
)
BS609 EJECTOR FOR BOSUN STORE
E/R
F.W TK
BOSUN STORE
BS005
BS009
EJECTOR FOR FWD PUMP ROOM BS607
FROM FIRE MAIN
BS011
BS010
FROM FIRE MAIN
EJECTOR FOR BOW T. ROOM BS608
BS017
SCANTL'G DRAFT (12.5M A/B)
BS013
A.P TK
BILGE HAT (P & S) SEE DETAIL
BS012
BS014
ENGINE ROOM S.T.C.W. TK
FROM FIRE MAIN BS204 SPECTACLE FLANGE
FR15
BS203 BS611 BILGE EJECTOR FOR P. DUCT/COFFERDAMS
S.T.C.W. TK
FR71
FR86
FR103
FR120
FR134
FR157
BS018
BS015
BS020 BS019 BS201 BS051 BS202
BS045
B/W
BS047
BS039
B/W
PIPE DUCT
BS048
BS033
B/W
BS041
BS042
BS027
B/W
BS035
BS036
BS029
BS025 BS022
BS030
B/W
BS021
A.P TK
BS016 BS205
SCANTL'G DRAFT (12.5M A/B)
FWD P/P RM
B.W
DIST. W TK
BS004
C.L BS003
BOSUN STORE BS602
BS606
UPPER DECK 65A
BS313
BS302
BS312
BS301
PLA
FROM FIRE MAIN
FROM FIRE MAIN MOTOR RM
COMP. RM
UPPER DECK
CARGO STORE
DE (T TAIL YP .)
UPPER DECK 60
TRUNK DECK
N
60.5
6
2~4 20
F.W RM
ABOUT 15
250 Ø10 HOLES
Ø 10 HOLES
WALL
6
242 ABOUT 15
13
267.4
DETAIL OF BILGE HAT
4 - 69
Part 4 Cargo and Ballast System
LNGC DISHA
Cargo Operating Manual
4.16 Loading Computer
4.16.2 Software Configuration
5. Loading Status : picture of ship tanker rate , profile, plan, section
General
Pull Down Menu You can manage loading condition files by use of file menu. this menu contains several sub menus and of each menu function is as follows.
Leading the trend in shipboard calculation, data processing, ship-shore communication and vessel automation, Techmarine Co. Ltd. provides you modern microprocessor-based loading computer, "SHIP MANAGER", that carries extremely powerful loading calculation and other software for standard computer.
1. OnLine : Select On-Line mode between the ICMS and the Loading Computer 2. OffLine : Select the Off-Line mode between the ICMS and the Loading Computer 3. Line Setup… : Select menu “ON” and “OFF” in the online status.
The whole system is designed to be used by non-computer oriented users such as ship's officers and/or shore-based cargo planners with no specific knowledge on how to run the about computer’s system.
This material explains the full aspects of the "SHIP MANAGER" loading programs, the major functions of which are as follows :
4.16.1 ON-Line and OFF-Line Mode 1. 2. 3. 4. 5.
Displacement/Deadweight/Trim & Draft(aft and fore) Correction Drafts(aft and fore) due to difference of sea water density LCG/VCG/TCG/Metacentric height / Angle of heel. Trim & adjusting calculation / Heel adjusting calculation Cargo/Ballast/F.O/D.O/L.O/F.W tanks shall have maximum free surface moment regardless of liquid level. 6. Display Cargo/ballast/F.O/D.O/L.O/F.W & D.W/tanks level & volume. 7. Intact stability calculation(*) 8. Shear forces and bending moments at the prescribed frame point(*) 9. Corrected shear forces required by Classification Society(*) 10. Maximum values of shear force and bending moment. 11. Propeller immersion (*) 12. Forward draft limit (*) 13. GM limit (*) 14. Cargo tank filling restrictions against sloshing effect(*). 15. GZ curves for loading conditions. 16. Result of visibility(SOLAS V.22) with warning message(*) 17. Curves of calculated S.F and B.M and maximum allowable values required by Classification Society. 18. Automatic Calculation Specific gravity, percentage filling, tank level, volume and weight for liquied compartments when one of these is given. 19. The system will be designed for loading calculation on the basis of “on-line” and “off-line” modes and selected mode can be identified easily. (*) marked items shall be displayed with warning message & alarm signal against given limitations 20. On-line interface with IAS(RS 485 type) – Cargo tanks, ballast tanks, FO/DO/LO/FW/DIST. W. / Draft 21. Direct damage stability calculation (IGC code) 22. Weather stability calculation
1. 2. 3. 4. 5. 6.
New Plan : Create a new loading condition. Lightship condition is created. Open Plan : Read the loading file(*.LDP) saved in the current directory. Save Plan : Save the loading current status to disk with a specific file name. Save As : Save the loading current status to a disk with a different file name. Delete Plan : Delete the loading file saved in the current directory. File Explorer : You can use the File Explorer to format disks, make backup, get an overall view of your file system and so on. 7. Print : Print out a selected item. 8. Print Setup : Printer setup. 9. Exit : Exit 'ShipManager-88' session.
1. Weather Criteria : Data and graph calculated by the IMO.A 562(18) CRITERIA. 2. Intact Stability Results : Data and graph calculated by the IMO.A 749(18) CRITERIA. 3. Longi. Strength : The ratio of the actual Shear force/Bending moment (allowable Shear Force/Bending moment on each bulkhead at sea/port and their graph Maximum Shear force/Bending moment and their position.) 4. Damage Stability : Data calculated by the IGC Code Criteria. ‘Tank Top Plan’, and ‘Midship section’.
4 - 70
1. Calculators…: Leads you to the MS-windows Calculator. (See MSWINDOWS manual ) 2. Control Panel…: Leads you to the control panel, where it is possible to change colors, and printer attributes. 3. Shifting… : Shifts the load from one compartment to another. 5. Trim Adjust : Carries out adjustment of trim by adding cargo/ballast water to two designated compartments. Trim with Cargo add : Controls the trim by adding weight 1 Trim with Cargo shift : Controls the trim by moving weight 6. Heel Adjust : carries out adjustment in the of heel by ballast water to two designated compartments. 7. Rolling Period… : Shows and Calculate Rolling Period 8. Propeller Immersion… : Shows information on Propeller Immersion 9. Hydrostatics… : Shows the following information follows Displacement, Draft equiv., LCG, LCB, MTC, LCF, TKM, KG. etc. 10.Kn Table : Show Kn information. 11.Visibility : Show each position from Sight End ,conning.
Part 4 Cargo and Ballast System
LNGC DISHA 12. Hydrostatics View : Shows information on the actual condition of the as following: DWT, LWT, DISP. Draft equiv., LCG, LCB, MTC, LCF, TKM, KG. Draft at marks. 1 degree heeling moment. Etc.
Cargo Operating Manual 4.16.3 Explanation of the Ship Manager Screen The above screen is classified into 'PULLDOWN MENU', 'SPEED BUTTON MENU', 'WARNING PANEL', ‘WORK TAB’ and 'STATUS PANEL'. 1) PULLDOWN MENU This part controls the loading program and is regulated by the pull down method.
