JACOBS (HPCL)STANDARD ON PRESSURE VESSEL & HE.pdf

Page 1 of 52

HINDUSTAN PETROLEUM CORPORATION LTD. MUMBAI DIESEL HYDROTREATER PROJECT

TITLE:

ENGINEERING DESIGN BASIS PRESSURE VESSELS & HEAT EXCHANGERS

DOCUMENT NO : 44LK-5100-V.02-0001-A4

REV NO.

ISSUE DATE

PAGES

REV DESCRIPTION

PREPARED

CHECKED

APPROVED

BY

BY

BY

A

15.02.2008

52

Issued for Client’s approval

SNK

CR

HSC

0

10.09.2008

52

Clients comments incorporated & issyed

SNK

CR

HSC

JACOBS Engineering Design basis for

HPCL-MUMBAI 44LK5100

Page 2 of 52

Pressure vessels & heat exchangers

Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

TABLE OF CONTENTS CODES & STANDARDS 1.1

CODES

1.2

STATUTORY REQUIREMENTS

1.3

INTERNATIONAL REQUIREMENTS

2.0

DESIGN BASIS – GENERAL

2.1

SIZING OF EQUIPMENT

2.2

SHELL/ HEAD THICKNESS

2.3

VESSEL END CLOSURES

2.4

DESIGN PRESSURE

2.5

DESIGN TEMPERATURE

2.6

HYDRO TEST PRESSURE

2.7

CORROSION ALLOWANCE

2.8

WIND LOADING CONSIDERATION

2.9

SEISMIC LOADING CONSIDERATION

2.10

CAPACITY

2.11

SUPPORTS

2.12

MANHOLES

2.13

FLOATING ROOF

2.14

NOZZLE SIZE

2.15

FLANGES

2.16

INTERNALS

2.17

GASKETS

2.18

PIPE DAVIT

2.19

SPARES

2.20

VENT/ DRAIN/ VENTILATION NOZZLE CONNECTION

2.21

IMPORTANT CONSIDERATIONS

3.0

DESIGN REQUIREMENTS – SPECIFIC APPLICATIONS

3.1

TALL COLUMNS

3.2

STORAGE TANKS

3.3

HYDROGEN BULLETS

3.4

REACTORS

3.5

SHELL & TUBE HEAT EXCHANGERS

3.6 3.7 3.8 3.9

ADDITIONAL REUIREMENTS FOR SPECIAL TYPE HIGH PRESSURE HEAT EXCHANGERS AIR COOLED HEAT EXCHANGERS DOUBLE PIPE HEAT EXCHANGERS PLATE HEAT EXCHANGERS

TABLE – 1

DETAIL & WEIGHT OF COLUMN ATTACHMENTS

TABLE – 2

ALLOWABLE STRESS FOR COMBINED LOADING

TABLE- 3

MATERIAL SELECTION CHART

Section B

TRAYS AND TOWER INTERNALS



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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

1.0

CODES & STANDARDS

1.1

CODES The following applicable codes, Licensor’s Global Practices (GP’s) Applicable rules and regulations and laws of India and their applicable standards in their latest edition including latest addenda shall be followed unless otherwise specified for the design, fabrication, inspection and testing of Vessels, Columns, Reactors, Storage Tanks, Shell & Tube heat exchangers, High pressure heat exchangers, Air cooled heat exchangers, Double pipe exchangers, Plate heat exchanger, Steel Flare/ Vents Stacks : ASME SEC. VIII DIV. 1

For Pressure Vessels

ASME SEC. VIII DIV. 2

For Pressure Vessels (as specified in bid package for high shell wall thickness of equipment)

ASME SEC VIII DIV 3

For very high pressure Vessel

TEMA CLASS ‘R’, 1999 EDITION.

For Shell & tube Heat Exchangers

ASME SEC. VIII DIV. 2/PD 5500

Mounded Vessels / Bullets.

ASME SEC.V

For non-destructive testing

TEMA, 1999 EDITION / IS 800

For double pipe exchanger (To the extent applicable)

ASME SEC. II Part A, B, C, D

For material specification & allowable stresses

ASTM/ IS

For material specification for Tanks

ASME Sec. IX

For welding

ASME B 16.5

For flanges

ASME B 16.47

For large diameter flanges

ASME B 16.20 / API 601

For gaskets

ASME B 96.1

Welded Aluminum alloy storage tank

ANSI B1.1/IS 4218

For bolting specification

ASME B 16.28

For elbows & return bends

ASME SEC. VIII Div. 1

For workmanship of Vessels not categorized under any other code

API 650

For Storage Tanks

API Standard 661 / IS 800 Latest edition

For Air cooled exchangers

API 620

For Low Pressure Storage Tanks

IS: 6533

For steel vent stacks etc

JACOBS HPCL-MUMBAI 44LK5100

1.2

Engineering Design basis for

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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

IS: 9178/DIN 1055

For Silos, Hoppers and, Bins

IS: 875/ Site Data

For wind load consideration

IS: 1893/ Site Data

For seismic design consideration

IBR

For steam producing, steam storage, catch water vessels, condensate flash drums and similar vessels

STATUTORY REQUIREMENTS National laws and statutory requirements such as of Indian Boiler Regulations and requirements of Department of Explosives, Nagpur, India together with any local by-laws for the state shall be complied with. Static and Mobile Pressure Vessel (SMPV) rules and Petroleum rules, Directorate (OISD) etc. as applicable shall also be complied with.

1.3

INTERNATIONAL PUBLICATIONS

NACE MR 0175

Sulfide Stress Cracking Resistant Metallic Materials for Oil Field Equipment

NACE TM 0284

Evaluation of Pipeline and Pressure Vessel Steel for Resistance to Hydrogen Induced Cracking.

NACE TM 0177

Laboratory Testing of Metals for Resistance to Sulfide Stress Cracking in Hydrogen Sulfide Environment

NACE RP 0472

Methods & controls to prevent in service cracking of CS welds in P1 materials in corrosive petroleum refining environments

WRC Bulletin # 107

Local Stresses in Spherical & Cylindrical Shells due to External Loadings

WRC Bulletin # 297

Local Stresses in Cylindrical Shells due to External Loadings on Nozzles

WRC Bulletin # 368

Stresses in intersecting Cylindrical Shells subject to pressure

API-RP-945

Avoiding environmental cracking in Amine Units

API-950

Survey of construction Materials and corrosion in sour water stripper


2.0


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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

DESIGN BASIS – GENERAL All equipment shall be designed in accordance with the latest design codes, and applicable standards/ specifications. Design calculations shall be made considering all loads for Erection, Operating and Hydro test conditions (ref. Para.3.2.2)

2.1

SIZING OF EQUIPMENT All equipment columns, clad/lined vessels, vessels (including thickness ≥ 50 mm), tanks, bullets & all others vessels shall be sized on THE basis of internal diameter only.

2.2

SHELL/HEAD THICKNESS (Minimum)

2.2.1

For columns of carbon and low alloy steel, minimum thickness shall be 8 mm (including corrosion allowance up to 3.0 mm). The minimum thickness of carbon and low alloy steel vessels shall be 6.0 mm (including corrosion allowance not exceeding 3.0 mm) but shall not be less than calculated as per following formula : For diameter less than 2400mm:

Wall thickness = Dia + 1.5 + Corrosion Allowance. 1000 For diameter 2400mm and above: Wall thickness = Dia + 2.5 + Corrosion Allowance. 1000 All dimensions are in mm. Above formula is applicable for both columns & vessels. 2.2.2

For columns of stainless steel and high alloy steel, minimum thickness shall be 5mm. Corrosion allowance shall be added in this minimum thickness as specified in process data sheet. The minimum thickness of stainless steels & high alloy vessels shall be 3.0mm but shall not be less than calculated as per following formula: For diameter more than 1500 mm Wall thickness = Dia + 2.5 + Corrosion Allowance. 1000 Corrosion allowance (if any) shall be added to minimum thickness as specified. Above formula is applicable for both columns & vessels.

2.2.3

Tangent to tangent height (H) to diameter (D) ratio (H/D) greater than 5 shall be considered as tall column and designed accordingly.



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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

2.3

VESSEL END CLOSURES

2.3.1

Deep torispherical dished end with 80% crown radius and 15% knuckle radius or alternatively 2:1 semi-ellipsoidal dished end shall be used for pressure vessels unless otherwise specified. Seamless dished ends shall be used for specific services as per process licensor requirement.

2.3.2

Unless specified otherwise, hemispherical ends shall be used when the thickness of shell exceeds 70 mm.

2.3.3

For atmospheric vessels, flat covers may be used.

2.3.4

For vessels diameter < 600 mm, without any internals, pipe caps may be used.

2.3.5

Manholes will be provided for all process vessels over 36 inches (760 mm) in diameter. Smaller vessels will normally be provided with hand holes or a flanged head, depending upon access requirements for the particular service. Manhole where provided must have minimum 19 inch ID unless a larger dia manhole is indicated in the data sheet. Body flanges may be provided in lieu of Man holes for vessels with dia ≤ 760 mm.

2.3.6

All process vessels that have a manhole will also be specified to have a vessel vent to provide ventilation for maintenance. This vessel vent will be located at the top, or a minimum distance from top of vessel. Size of this vent shall be as follows. Vessel capacity Upto 200 m3 3 200-400 m 3 400-700 m >700 m3

2.3.7

size of vent (NB) 3 inch 4 inch 6 inch 8 inch

All tower and drums will be provided with valved drain connections, terminating in a line size block valve and blind. The drain will be provided from a bottom draw off line of at least equal size. Vessel drain sizing will be per the following : Vessel volume (m^3 ) Upto 200 m^3 200-400 m^3 400-700 m^3 >700 m^3

process drain inches 3 3 4 6

2.3.8

If the equipment process data sheet indicates sour service (alkaline or wet H2S service), the equipment materials, their testing , their post weld heat treatment and any other recommendations of the NACE materials recommended by the licensor and pertinent publications like NACE MR 175 shall be complied without exception.

2.3.9

For Vessels/ Columns of Diameter < 900 mm with internals, flanged covers may be used.



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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

2.3.10

Columns less than 900 mm diameter shall be provided with intermediate body flanges. Number of intermediate body flanges shall be decided based on column height and type of internals. Trays and other column internals installation shall be given consideration in deciding the size and location of manholes, hand holes or body flanges as the requirements may be at the initial design itself.

2.4

DESIGN PRESSURE Design pressure shall be calculated based on the following general guide lines unless otherwise specified elsewhere. When specified in the Process Data Sheet same shall be followed: 1

2.4.1

When operating pressure is up to and including 70 kg/cm2 g = operating pressure + 10% (minimum 2.0 kg/cm2 g)

Design pressure 2.4.2

When operating pressure is above 70kg/cm2 g 2

= operating pressure + 5% (minimum 7 kg/cm g)

Design pressure

Operating pressure should be maximum operating pressure for clause 2.4.1 and 2.4.2. 2.4.3

Design pressure shall be at the top of vertical vessel or at the highest point of horizontal vessel.

2.4.4

The design pressure at any lower point shall be calculated by adding the highest operating liquid head (and any pressure drop within the vessel) to the calculated hydro-test pressure.

2.4.5

Equipment with steam out condition shall be designed for full vacuum condition.

2.4.6

Equipment operating under vacuum / partial vacuum shall be designed for an external pressure of 100 kPa (15 psi g) 1

2.4.7

Vessels shall be designed for steam out conditions if specified on process data sheet.

2.4.8

Minimum design pressure shall be 3.5 kg/cm g for any equipment except API storage tanks.

2.4.9

All storage tanks shall be designed as per code considering full height & using specific gravity 1.0 if not specified.

2.4.10

Pressure chambers of combination units in equipment shall be designed for testing independently without pressure in the adjacent chamber in corroded condition, unless otherwise specified elsewhere.

2.5

DESIGN TEMPERATURE

2.5.1

For vessels operating at 0 C and above, if not specified in the Process Data Sheet,

2

o

Design temperature 2.5.2

o

o

= maximum operating temp. + 15 C (subject to a min of 65 C)

For Vessels operating below 0 oC if not specified in the Process Data Sheet, Design temperature

1

= lowest operating temperature

1



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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

2.5.3

Minimum Design Metal Temperature (MDMT) shall be lower of minimum atmospheric temperature and minimum operating temperature encountered during operation.

2.5.4

Un-insulated vessels containing LPG and similar fluids shall be designed for maximum & minimum temperature as recommended by SMPV rules.

2.6

HYDRO TEST PRESSURE

2.6.1

Equipment shall be hydro tested in the fabricator’s shop as per applicable design code & specification requirements. However care shall be taken that hydrostatic temperature shall be at least 6 degree centigrade higher than critical exposure temperature (CET) for vessel thickness up to 50 mm and minimum 17 degree centigrade higher than the CET where CET is minimum design metal temperature (MDMT). However, if code requirement is found to be stringent, than the same shall be followed.

2.6.2

All vertical vessels, columns and horizontal vessels (in full corroded condition) shall also be designed for site testing of the equipment with water at the test pressure on the top of the equipment considering 50% of design wind load.

2.6.3

All equipment foundation shall be designed and constructed for water full condition when equipment is new with 50% of design wind load.

2.6.4

Open atmospheric vessels shall be tested by filling water up to the top curb angle.

2.6.5

Pressure chambers of combination units that have been designed to operate independently shall be hydro tested to code test pressure as separate vessels i.e., each chamber shall be tested without pressure in the adjacent chamber. When pressure chambers of combination units have their common elements designed for maximum differential pressure, the common elements shall be subjected to test pressure equivalent to the differential pressure multiplied by a factor as per applicable design code.

2.6.6

Coils shall be hydro tested to code test pressure separately.

2.6.7

Unless otherwise specified in applicable design code allowable stress during hydro test in tension shall not exceed 90% of yield stress point.

2.6.8

Storage tanks shall be tested as per applicable code.

2.7

CORROSION ALLOWANCE

2.7.1

3.0 mm minimum corrosion allowance for carbon steel columns, vessels and atmospheric vessels shall be used unless otherwise specified.

2.7.2

1.5 mm minimum corrosion allowance for low alloy steel columns and vessels used unless otherwise specified.

2.7.3

No corrosion allowance for stainless steel columns & vessels shall be used unless otherwise specified.

2.7.4

For cladded/lined vessels, no corrosion allowance is required on the base material. Minimum 3.0 mm cladding (undiluted) shall be considered as corrosion allowance unless otherwise specified.

shall be



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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

2.7.5

If it is agreed to develop the cladding by weld overlay method , then it shall be ensured to have undiluted chemistry of the cladding upto specified thickness of cladding. Surface texture requirement if applicable shall also be ensured. Code requirements of PWHT and any specified NDT shall also be complied .

2.7.6

For storage tanks, minimum corrosion allowance shall be as follows unless otherwise specified: Bottom plate

= 3.0 mm

First shell course

= 3 mm

Subsequent shell courses

= 1.5 mm

Floating roof/fixed roof

= 0.5mm

2.7.7

Buried vessels shall have 1.5mm external corrosion allowance. Vessel shall also be applied with a proven external corrosion resistant coating.

2.7.8

Spheres / mounded bullets shall have 1.5 mm corrosion allowance.

2.7.9

Cladding or lining thickness shall not be included in strength calculations? (stress analysis)

2.7.10

Corrosion allowance for nozzles including manholes shall be at least equal to that specified for the vessel. No corrosion allowance is required for standard flange face.

2.7.11

Corrosion allowance for gasket faces of girth/ body flange or specially designed non standard flanges shall be used equal to that specified for vessel.

2.7.12

Corrosion allowance for support skirts of columns & vertical vessels shall be 1.0 mm (minimum) unless specified otherwise.

2.8

WIND LOADING CONSIDERATION

2.8.1

Design basis for wind loads shall be as per IS: 875. As per IS-875 (Part-3), 1987 definition of basic wind speed shall be peak gust velocity averaged over 3 second time interval at 10 m height above mean ground level with 50 years mean return period. Values of coefficients K1, K2 (or K2 for gust factor method of wind load calculation), K3 (as in IS: 875 – Part –3) for the project site (Mumbai) shall be considered as under.

2.8.1.1

Probability Factor K1 The design life of all equipment shall be taken as 50 years. The mean return period of all equipment shall be 50 years except for flare stack/ chimney for which the mean return period shall be taken as 100 years. Values of K1 for mean probable design life of equipment shall be as follows: (i)

1.0 for 50 years mean return period

(ii) 1.09 for 100 years mean return period (iii) K1 (columns and stacks height greater than 30 m ) = 1.09 2.8.1.2

Terrain, height and structure size factor, K2



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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

These factors are to be taken from IS 875 (Part 3) – 1987 for relevant class of the structures with respect to the actual height of the structures. Terrain category shall be considered as 2 for columns and stacks height greater than 30 m and 3 for other equipment in units 2.8.1.3

Topography factor, K3 = 1 Surface area of piping, platforms and other attachments fixed to the equipment (Vessel / Column) exposed to wind shall be accounted

2.8.2

Drag coefficient for cylindrical vessels shall be 0.7 minimum

2.8.3

Drag coefficient for spherical vessel shall be 0.6 minimum

2.8.4

Contingency factor of 1.1 shall be used on wind pressure if required.

2.9

SEISMIC LOADING CONSIDERATION Seismic loads shall be in accordance with design requirements for earthquake conditions for Zone –III as per IS 1893.

2.10

CAPACITY

2.10.1

Tank Capacity shall be specified as Nominal capacity and stored capacity. Nominal capacity for fixed roof tanks shall be volume of cylindrical shell. Stored capacity for fixed roof tanks shall be equal to nominal capacity minus free board volume (equivalent to 500mm of shell height) or location of fixing of lowest roof structure member Nominal capacity (also the stored capacity) for floating roof tanks shall be volume of cylindrical shell minus free board volume. (equivalent to minimum 1500mm of shell height). Nominal capacity (also the stored capacity) for fixed cum floating roof tanks shall be volume of cylindrical shell minus free board volume. (equivalent to minimum 2500 mm of shell height).

2.10.2

Bullets (above ground or under ground) Nominal capacity is the geometric capacity of bullet. Stored capacity shall be 85% of nominal capacity at maximum design temperature.

2.10.3

Sphere Nominal capacity is the geometric capacity of sphere. Stored capacity shall be 85% of nominal capacity at maximum design temperature.



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DOC.NO. 44LK5100-00-V.02-0001-A4

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2.11

SUPPORTS

2.11.1

Skirt supports shall be provided for all l tall columns (refer cl.2.2.3) and reactors. Small vertical vessels may be supported on legs (pipes or structural section) or brackets.


2.11.2


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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

All Cr-Mo steel reactors shall be supported on skirts. Welding of external cleats on Cr-Mo steel reactors shall be avoided wherever possible.

2.11.3

Skirt thickness The minimum thickness for the skirts shall be greater of: (a) The thickness required by stress analysis with a minimum of 6 mm inclusive corrosion allowance (b) 1/3 of the shell wall thickness with a maximum of 30 mm Corrosion allowance of 1.0 mm minimum shall be considered for skirts unless otherwise specified.

2.11.4

Columns with diameter larger than 900 mm shall be self supported unless the process data sheet indicates a guide supported design.

2.11.5

Columns with diameter less than & including 900mm shall be supported by superimposed structure around the column covering the entire height. Guy wires shall not be used to support any equipment. Supporting of columns by superstructure require prior approval from Jacobs

2.11.6

In special cases, columns with diameter up to 900mm and height not exceeding 20m (including skirt height) can be self-supported and heights exceeding 20m shall be supported by super imposed structure around the column covering the entire height.

2.11.7

Flare and vent stacks shall be supported structurally by superimposed structure around for complete height.

2.11.8

Storage spheres shall be supported on pipe leg supports with tie rod bracing and turn buckles.

2.11.9

Buried vessels shall be suitably anchored to prevent the uplift due to water table. Anchor bolts shall have corrosion allowance of 6mm. Buried vessels shall be supported on concrete saddles with anchoring bracket support at the centre line of the vessel.

2.11.10

All vertical equipments shall be provided with suitable lifting arrangements.

2.11.11

All skirt supported columns/equipments with height 20 m and above and weight 50 MT and above are to be provided with tailing lug.

2.12

MANHOLES

2.12.1

Manhole size less than 480 mm ID shall be avoided. If the dia of vessel is small, check if a hand hole or a body flange can be considered however, Vessels less than 900 mm ID shall be provided with hand holes or flanged heads, depending upon access requirement for the particular service Vessels and columns with diameter 900mm shall be provided with 450 NB (Min ID 432 mm) manhole unless otherwise specified. Vessels and column with diameter greater than 1000mm and upto 1500mm shall be provided with 500 NB (Min ID 480 mm) man way. Vessels and columns with diameter 1500mm and above may be provided with 600 NB man way. However, when inside diameter of manholes are specified, then Inside diameter shall be considered as minimum required & a mandatory requirement.



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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

Size of manholes shall be as per licensor drawing.

2.12.2

For storage tanks minimum number of manholes (size 600mm) shall be as follows: Tank diameter

Shell manhole

Flush type clean out fittings (if specified)

Roof manhole

Dia. ≤ 12 m.

1

NIL

1

> 12m
2

1

2

45m < Dia. ≤ 61m.

3

2

2

Dia. >61m

4

2

2

For floating roof tank 1no. 750 mm NB manhole with internal ladder shall be provided as per fabricators standard. 2.12.3

Size of clean out doors fittings for tanks shall be 900mm x 1200mm.

2.13

FLOATING ROOF

2.13.1

Floating roof shall be of following construction unless specified otherwise.

2.13.2

Tank diameter

Type of roof

≤ 12 m

Double deck type (due to construction limitations)

≥ 12 m < 60 m

Pontoon type

≥ 60 m

Double deck type (for proper balancing)

1

1

(a) Primary and secondary seal to be provided for Naphtha, MS & Diesel service floating type roof tanks. Internal floating roof shall have single seal. (b) The roof drain shall be pivot master type.

2.14

NOZZLE SIZE

2.14.1

- Minimum nozzle size

40 NB

- Minimum nozzle size for clad vessels / columns

80 NB

- Safety valve nozzle

Based on I.D.

- Self reinforced nozzle neck

Based on I.D.

2.14.2

Nozzles and manholes including self reinforced type shall be “set in” type attached to vessel with full penetration welds unless otherwise specified.

2.15

FLANGES



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DOC.NO. 44LK5100-00-V.02-0001-A4

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2.15.1

Nozzle flanges upto 600 NB shall be as be ASME / ANSI B16.5 and above 600 NB shall be as per ASME / ANSI B 16.47 (SERIES ‘B’).

2.15.2

Nozzle flanges shall be welding neck flanges unless specified otherwise. Nozzles less than 50 NB shall be of long weld neck type .

2.15.3

Slip on flanges shall not be used in Lethal, Hydrogen, Amine, Caustic, severe cyclic service, sour service, HIC (Hydrogen induced cracking) service and corrosive service where corrosion allowance is more than 3 mm.

2.15.4

Specially designed flanges for process nozzles shall not be used.

2.15.5

Girth flanges and intermediate body flanges shall be of weld neck type only.

2.15.6

Flange rating shall be established based on design pressure, design temperature and considering all external loads (moments and axial force). Nozzle flanges 900# rating & above shall also be designed as per ASME SEC. VIII DIV.1 appendix-2 considering design pressure and design temperature. Change in basic constructional features of the flanges is not permitted.

2.16

INTERNALS All removable internals shall be bolted type and bolting shall be SS type 304 unless specified otherwise.

2.17

GASKETS

2.17.1

Service gaskets supplied shall not be used for hydro testing purpose. Gasket used for hydro testing of equipment shall be of same specification as that of service gaskets for all nozzles, manholes and body/girth flanges. Gasket seating face of flanges shall have finish as per gasket specified.

2.17.2 0

All SS spiral wound gaskets shall be provided with outer and inner rings

2.17.3 0

When RTJ type of facing is provided, gasket shape shall be round and not hexagonal, in order to avoid sharp edges in the groove

2.18

PIPE DAVIT All columns and Vertical vessels with internals & safety valve size 80 NB shall be provided with pipe davit as per Jacobs standard.

2.19

SPARES Gaskets: Four (4) sets for manholes, two (2) sets for other gasketted joint. Fasteners: 10% (minimum 2 in each size) Sight / Light glass: 4 sets for each installed glass. Internals: (Valves for Trays, Bolts / Nuts, Clamp Assemblies)-10%, Sealing foils for Cartridge Trays-200%

2.20

VENT / DRAIN / VENTILATION NOZZLE CONNECTIONS:



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Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

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All vent and drain lines of light HC like MS, naphtha, LPG, propylene, and H2 shall be provided with double isolation valves with end flanges as per OISD. Dia. 15 NB and above drain lines should be provided with end flanges. All vessels shall be provided with one number vent / drain connection as per following unless otherwise specified in process data sheet. Vessel Volume Less than 6.0 m3 6.0 – 15.0 m3 More than 15 m

3

Length (Horizontal Vessel) -

Vent nozzle 40 NB

Drain nozzle

Ventilation nozzle

40 NB

-

-

50 NB

40NB

-

-

50 NB

80 NB

-

-

3000mm – 4500mm

-

100 NB

-

4500mm – 7500mm

-

150 NB

-

≥ 7500mm

-

200 NB

All vertical vessels not having any nozzle on the top shall be provided with 50 NB nozzles for conducting hydro test in vertical conditions. 2.21

IMPORTANT CONSIDERATIONS

2.21.1

All vessels and columns shall be designed considering design pressure; maximum operating liquid head and any pressure drop within the vessels/columns.

2.21.2

All columns and vessels shall be capable of withstanding water full condition during system testing.

2.21.3

Vessels and columns shall be hydro tested at shop at pressure calculated as per applicable code in new and cold condition.

2.21.4

Seismic design shall be carried out based on design requirement for earthquake.

2.21.5

Equipment covered under the purview of IBR (Indian Boiler Regulations) shall be designed as per IBR regulations. However, design of components not covered in IBR Regulations shall be designed in accordance with ASME SEC. VIII Div-1.

2.21.6

Detail stress analysis, local load analysis for loads due to piping and supported equipment etc. shall be carried out for all equipment. Critical equipment shall be analyzed by using finite element analysis methods (FEM) as defined in job specifications & reports shall be submitted for Jacobs review. For allowable nozzle loads refer Jacobs standard specification attached with BID package.

2.21.7

All nozzle necks, all nozzle flanges and blind flanges shall be of weld overlay construction for clad equipment. Loose liners on nozzle necks and blind flanges are not permitted.

2.21.8

All vertical vessels and columns shall be provided with 2 lifting lugs/Lifting trunions. Lifting lugs shall be designed with impact factor of two.

2.21.9

Mechanical design of self supporting Tall columns / tower shall be carried out for various load combinations as per Clause 3.2



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DOC.NO. 44LK5100-00-V.02-0001-A4

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2.21.10

Material of various parts of equipment shall be selected as per table given in TABLE– 3 unless otherwise stated on process data sheets.

2.21.11

Local Stress analysis shall be carried out for nozzle to shell junction using maximum shear stress theory for vessels and columns. Allowable stress intensity shall be as per ASME SEC. VIII Div. 2 and non-destructive examinations shall be carried out for shell to nozzle junction as per ASME SEC. VIII Div. 2.

2.21.12

Stress analysis of shell to skirt junction shall be carried out using maximum shear stress theory for vessels and columns designed as per ASME Sec. VIII Div. 2. In case skirt shell joint is of butt-welded construction, the same shall be 100% radiographed.

2.21.13

All vessel, columns and tanks shall be provided with earthing bosses as per Jacobs standard. Body flanges of equipment shall have provision to provide jumpers for earthing.

2.21.14

Permanent fixed ladders shall be provided inside the skirt of columns/vertical vessels for inspection of dome / dished end.

2.21.15

ODC/Very heavy equipment shall require special considerations for transportation and erection by Contractor.

2.21.16

All equipment shall be painted as per Jacobs painting specification.

2.21.17

All equipment requiring insulation shall be provided with insulation support rings /cleats as per Jacobs specifications.

2.21.18

All ladders and platforms shall be galvanized.

2.22

CATHODIC PROTECTION: Impressed current cathodic protection system shall be designed and installed as per the Jacobs specification



2.23

Page 17 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

EXTERNAL COATING: Applied protection shall be designed and installed as per the Jacobs specification

2.24

INTERNAL COATING: Bottom 90-degree of internal surface of vessel shall be coated with anti-corrosion coating suitable for stored product.

2.25

LOCATION/SPACING OF VESSELS: Minimum spacing of vessels and other safety regulations shall be as per OISD-STD-150.

3.0

DESIGN REQUIREMENTS-SPECIFIC APPLICATIONS

3.1

TALL COLUMNS Mechanical design of self-supporting column and its anchorage block shall be carried out considering combination of various loads.

3.1.1

Loadings: The loadings to be considered in designing a self supporting column / tower shall include: a) Internal and or external design pressure specified on process data sheets. b) Self weight of column inclusive of piping, platforms, ladders, manholes, nozzles, trays, welded and removable attachments, insulation and operating liquid etc. The weight of attachments to be considered shall be as per Table–1 c) Other loadings as specified in UG-22 of ASME SEC. VIII Div. 1 wherever applicable. d) Seismic forces and moments shall be computed in accordance with design requirement for earthquake. Unless otherwise specified importance factor and damping coefficient shall be considered as 2 and 2% respectively. e) Basic wind pressure and wind velocity (including that due to winds of short duration as in squalls) for the computation of forces / moments and dynamic analysis respectively shall be in accordance with IS 875 (latest edition)(Refer Clause 2.8 above). Additional wind loading on column due to external attachments like platforms, ladders, piping and attached equipment should be given due consideration. Loadings resulting in localized and gross stresses due to attachment or mounting of reflux / reboiler, condenser etc.

3.1.2.

Loading condition

3.1.2.1

Analysis shall be carried out for following conditions: (a) Erection condition:

Column (uncorroded) erected on foundation without insulation, platforms, trays, removable internals etc., but with welded attachments plus full wind on column.



Page 18 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

(b)Operating condition:

Column in (corroded condition) under design pressure, including welded items, trays, removable internals, packing/catalyst piping, platforms, ladder, reboiler mounted on column, insulation and operating liquid etc., plus full wind on insulated column with all other projections open to wind or earthquake forces.

(c) Test conditions

Column (in corroded condition) under test pressure, filled with water plus 33% of specified wind load on uninsulated column including all attachments shall be considered.

3.1.2.2

Earthquake and wind shall be considered not acting concurrently.

3.1.2.3

Cyclic loads if any to be considered.

3.1.3

Deflection of column: Maximum allowable deflection at top of column shall be equal to total height (including skirt height) of the column divided by 200 but shall not exceed 300 mm in any case.

3.1.3.1

If the deflection of column exceeds the above allowable limit, the thickness of skirt shall be increased as first trial upto a maximum value equal to the column thickness and this exercise shall be stopped if the deflection falls within allowable limit.

3.1.3.2

If the above step is inadequate, skirt shall be gradually flared to reduce the deflection. Flaring of skirt shall be stopped if the deflection falls within limits or half angle of cone reaches maximum limit of 9°.

3.1.3.3

If the above two steps prove inadequate in limiting the deflection within allowable limits, the thickness of shell courses shall be increased one by one starting from bottom course above skirt and proceeding upwards till the deflection falls within allowable limits.

3.1.3.4

3.1.4

For tall equipment fabricated from stainless steels and other exotic materials, it shall be examined if an external guide will be helpful in controlling the required thickness such that the equipment along with its guide structure cost is economical than a free standing design Stress Limits The stresses due to design pressure, weights (erection/operating/hydrotest as the case may be), wind/seismic loads shall be combined using maximum principal stress theory for ASME SECTION VIII Div.1. Thicknesses are accordingly chosen to keep the stresses within limits as per Table-2.

3.1.5

Skirt support base Base supporting including base plate, anchor chairs, compression ring, foundation bolting etc., shall be designed based on over-turning moment (greater of seismic or wind). Minimum size of anchor bolts shall be M24. A minimum number of 8 foundation bolts shall be provided. Numbers of foundation bolts shall be in multiple of four. Skirt thickness shall also be checked to anchor chair reaction forces. Anchor bolts shall be so spaced that there is no interference between fixing arrangement, Anchor bolt sleeves etc.



3.1.6

Page 19 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

Hydro test pressure Hydro test pressure shall be equal to Q (A factor depending on code of construction) x design pressure x temperature correction factor as specified in ASME SEC. VIII DIV.1(Clause UG-99) / DIV 2 at top of column unless specified otherwise. If column is tested in horizontal position, hydro test pressure shall be increased in order to take the effect of water head.

3.1.7

Dynamic analysis of column / Tower Dynamic analysis of each column shall be carried out for stability under transverse wind induced vibrations as per standard design practice and calculations for each column shall be submitted to Jacobs for approval. The recommended magnification factor for unlined towers / column shall be taken as 70 and allowable dynamic amplitude shall be limited to tower diameter divided by 5.

3.2

STORAGE TANKS

3.2.1

Tank shell thickness calculation shall be carried out by the one - foot method as per API 650 for tank diameters less than and equal to 60m (200 feet).

3.2.2

Maximum height of un-stiffened shell shall be calculated based on the corroded thickness of shell courses. Section modulus of wind girders shall also based on corroded thickness of shell courses.

3.2.3

Shell thickness shall be calculated considering product liquid/water level up to top curb angle for all tanks including floating roof tanks.

3.2.4

Seismic design as per API-650 (appendix-E) is mandatory for all storage tanks.

3.2.5

Annular bottom plates shall be provided for all storage tanks ≥ 12.0 m diameter.

3.2.6

All small tanks ≤ 10.0 m diameter shall be provided with anchor bolts to prevent uplift due to wind.

3.2.7

Tanks having design temperature more than 100 C shall have thermal isolation barrier (Suitable insulating fire bricks) between tank bottom and foundation.

0



Page 20 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

3.3

HYDROGEN BULLETS

3.3.1

Hydrogen bullets shall be designed as ASME Sec VIII div.1. However, all fabrication and inspection requirements shall as per ASME Sec. VIII div.2.

3.4

REACTORS a) The design shall be done based on process licensors specifications. b) Material selection shall be strictly as per licensors specification. c) Minimum thickness shall be strictly be as per Licensors specification d) MDR and UDS as per ASME code shall be obtained by the fabricator. e) FEM analysis shall be done for all process nozzles, shell to head junction Y shaped skirt, welded/weld overlayed support rings and any other stressed point as defined in licensors specification f)

All internals shall have minimum thickness as given in process licensors specification and shall be designed for loads defined in licensors drawings.

g) Thermal analysis for HOT box shall be conducted. h) Reactors as well as internals shall be fabricated by process Licensors approved vendors, HPCL/Jacobs approved vendors. i)

Lifting arrangement shall be as defined by process Licensors drawings.

j)

Floating type insulation support shall generally be provided.

k) Reactor to be designed for minimum 25 years of life..



3.5

Page 21 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

SHELL & TUBE HEAT EXCHANGERS DENOTES APPLICABILITY

3.5.1.0

THERMAL DESIGN CRITERIA Thermal design criteria shall be as per process design basis.

3.5.1.1

0

SELECTION OF TUBE SIZE Selection of tube size and tube length shall be as per process design basis

3.5.1.2

0

TEMA TYPE SELECTION Selection of TEMA type and preference shall be as per process design basis

0

Preferred exchanger for refinery services shall be horizontal, single pass shell, floating head tube bundle (TEMA type “S”) arranged with two or more tube passes per shell. 3.5.1.3

OVERDESIGN MARGIN Over design margin shall be as per process data sheet

0

3.5.1.4

MINIMUM FLUID VELOCITY LIMITATIONS, IF ANY, shall be as per process data sheet

3.5.1.5

UTILITY SPECIFICATIONS shall be as per process data sheet

3.5.1.6

CORROSION ALLOWANCE CA is not applicable to tubes and baffles

3.5.1.7

0

0

OTHER REQUIREMENTS

3.5.1.7.1

MOC for Sea water cooled heat exchangers shall be as follows: 1)

2)

0

For exchangers where H2 / H2S is present Tubes, Tube sheets, Floating head,

Super Duplex

Baffles, Support Plates, tie rod, spacers etc.

Super Duplex

For exchangers where H2 / H2S is not present Tubes

Welded Titanium (0.9mm wall thk)

Tube sheet, floating head, baffle, tie rod Spacers

Ni-Al-Br

3.5.2.7.2

Do not stack exchangers when individual shell isolation and bypasses are provided.

3.5.2.7.3

Minimum design metal temperature (MDMT)

0

0C

0



Page 22 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

………. (specify) 3.5.2.0

MECHANICAL DESIGN CRITERIA

3.5.2.1

Bolting ( except nozzle bolting )

:

Inch TEMA Metric

3.5.2.2

Bolt loads

:

Full

Average

Forged (hubbed)

Plate

Shall be considered (in the same unit only) to the extent possible.

Not required

2 x Tube OD (Preferred)

1.5 x Tube OD (Min.)

3.5.2.3

3.5.2.4

3.5.2.5

Main Girth Flange

Bundle interchangeability

Radius of U-bends

:

:

:

3.5.2.6

Pulling of removable bundle (at both fixed and floating tubesheets)

:

Eyebolts for pulling out bundle shall be provided.

3.5.2.7

Min. flange connection size (except Multi-Purpose connection)

:

1 ½” NB

2” NB

8” NB _____ NB

10” NB & above

_____ NB

Extended

Non-extended

Non-extended for Stab-in-bundles of “B” type stationary head.

For CLAD EXCHANGERS

3.5.2.8

Nozzles from Seamless pipe upto

:

Nozzles may be rolled from plate (with 100% X-ray)

3.5.2.9

3.5.2.10

Tubesheet type for Floating head and U tube exchangers

Multi-Purpose (MP) Connection for PG/TI

:

:

One 2” NB connection on each process nozzle with blind flange For OTHERS One 1½” NB connection on each process nozzle with blind flange



3.5.2.11

Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

Minimum rating for Multi-Purpose /Instrument connection

3.5.2.12

Vent and Drain

3.5.3.0

MISCELLANEOUS ASPECTS

3.5.3.1

Davits

3.5.3.2

3.5.3.3

Page 23 of 52


Spares (Mandatory)

Testing Accessories

Same as Process nozzle

Same as Process nozzle with minimum # 300.

:

1 ½” NB nozzle (Separate vent and drain will not be provided if vented/drained by other nozzles or through MP connection, unless required by process datasheet / P&ID. In case MP connection provided on piping separate vent & drain on shell to be provided.

:

Shall be provided for channel cover and shell covers for exchangers

Not required

400% Gaskets

20% Bolting (Min. 4 studs and 8 nuts per joint)

Client to indicate additional requirement (if any)

Test rings shall be provided on all floating “S” & “T” type head type exchangers.

Dummy shell shall be provided for fixing test ring for exchangers such as kettle type or floating head without shell covers or stab in bundle where shell side design pressure is higher than tube side pressure.

Test flanges shall be provided.

:

:

:

For exchangers with removable bundle and bonnet (type channel) For exchanger with removable bundle and channel with flat cover if tube side pressure is greater than shell side pressure

Minimum number of test rings/test flanges/dummy shells shall be one per bundle.



Page 24 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

For shell side interconnected and stacked exchangers the minimum number of test rings shall be equal to the number of exchangers in one stack.

For “U” tube & floating head exchanger with Bonnet type channel, number of test flanges shall be equal to number of exchanger in one stack.

Yes as applicable (Water coolers are to be provided with sacrificial anodes. Inside channel box, channel cover and floating head covers to be painted with two coats of epoxy zinc phosphate primer and two coats of coal tar epoxy painting as per finish. For Duplex tubes use Aluminum sacrificial anode.

As per Bidder Qualification Criteria

3.5.3.5

Cathodic protection

3.5.3.6

Vendor selection

Notes

1)

Hydro testing of stacked exchangers shall be carried out in stacked condition.

2)

All the tube bundles of heat exchangers, coolers, and condensers should have impingement plate at the inlet side wherever possible.

3)

Admiralty brass/Cupro nickel tube bundles should be used in case of coolers and condensers. If brass tube bundle is not suitable due to process medium containing ammonia, hydrogen sulphide or due to temperature limitation, then duplex stainless steel or other suitable metallurgy shall be considered depending upon service.

:

All licensor requirements shall be complied with. However in case of any contradiction same to be resolved in consultation with the Owner/PMC/Licensor. 3.6

ADDITIONAL REQUIREMENTS FOR SPECIAL TYPE HIGH PRESSURE EXCHANGERS

3.6.1

Heat exchangers can be Screw Plug or Breech-Lock type or modified TEMA DEU type.

3.6.2

CORROSION ALLOWANCE:

3.6.3

1.

Corrosion allowance for pressure retaining parts shall conform to Process Data sheet.

2.

Weld overlay or cladding thickness shall be considered corrosion allowance. Unless otherwise specified on process data sheet, undiluted thickness of weld overlay shall be minimum 3 mm. Cladding minimum thickness shall not be less than 3 mm.

3.

No credit for strength shall be taken for cladding/weld overlay in the design.

4.

Corrosion allowance as specified on Process data sheet shall be added to all exposed surfaces of channel internals.

VACCUM CONSIDERATIONS: The exchanger including the channel internals shall be designed for full vacuum when specified.



Page 25 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

3.6.4

All inlet and outlet nozzles shall be designed as self reinforced nozzles with integral flanges.

3.6.5

Exchanger shall be designed considering external loads due to piping.

3.6.6

Nozzle flanges of higher ratings which are not covered in ASME B16.5 shall be designed as per ASME Sec. VIII Div. I.

3.6.7

Where units are stacked, the lower shell shall be designed to carry super-imposed load (full of water) of the upper shell. The corrosion allowance shall be deducted from the shell thickness before determining the external loading. In addition to the normal design loads, exchangers shall be designed to withstand a horizontal pulling load of twice the bundle weight.

3.6.8

U-bend radius shall be 2 times the tube OD minimum. The minimum thickness at U-bend after thinning shall not be less than the minimum thickness required by code. Tube thickness specified in data sheet for the exchangers is minimum to be adopted. Tube thickness if required for thinning allowances at U-Bend shall be increased.

3.6.9

Tube to tube sheet joint for all exchangers shall be strength welded.

3.6.10

Wherever applicable, longitudinal Baffle to tubesheet joint shall be full penetration weld with groove in tubesheet.

3.6.11

HYDROSTATIC TESTS

3.6.11.1

Procedure for hydro testing of the exchangers designed with differential pressure shall be as follows: a)

Pressurize only shell side to Q (A factor depending on code of construction) x differential design pressure x temperature correction factor as specified in ASME SEC. VIII DIV.1 (Clause UG-99 / DIV 2) and check tube to tube sheet joint and tube sheet to shell gasket leakage.

b)

Pressurize only tube side to Q (A factor depending on code of construction) x differential design pressure x temperature correction factor as specified in ASME SEC. VIII DIV.1 (Clause UG-99) / DIV 2 and check for tube to tube sheet joint leakage and tube sheet to shell gasket leakage.

c)

Pressure both shell side and tube side simultaneously to Q (A factor depending on code of construction) x design pressure x temperature correction factor on each side ensuring their differential pressure between the two sides, at no time to exceed Q (A factor depending on code of construction) times the differential design pressure corrected for temperature.

3.6.11.2

All vertical exchangers shall be tested in vertical position. Alternately, exchanger may be tested in horizontal position with test pressure modified with prior approval of Designer.

3.6.11.3

Stacked exchangers with nozzles interconnected shall be hydro tested in stacked condition except when the hydro test pressure of the individual exchanger is different.

3.6.12

Vendor shall supply required accessories for handling & maintenance including accessories / attachments for shell/ bundle pulling and accessories required for dismantling of Highpressure channel internals of all exchangers. Vendor shall supply fixtures required for dismantling channel cover.



Page 26 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

3.6.13

Vendor to supply one set of torque wrenches for bolt size M38 (1 ½ “) to M56 (2 ¼”) and a set of hydraulic bolt tensioner for bolt sizes greater than M56 (2 ¼”) in case these bolt sizes are being used in exchangers covered in the requisition.

3.6.14

SPARES. BOLTING

:

20% set screws, studs and nuts but not less than 4 studs (with 2 nuts for each stud) for each joint.

PUSH RODS

:

100% push rods (In case of Screw plug / Breech Lock exchangers)

SEALING STRIPS

:

100% Lamiflex sealing strips as applicable.

GASKETS

:

400% gaskets other than those used for hydro-testing and dispatch for each joint.

Spare bolting and gaskets shall be provided for all joints of girth flanges, channel cover, tubesheet, interconnecting nozzles, nozzles with blind flange etc. 3.6.15

Gasket Register for high pressure exchangers shall be maintained. All licensor requirements shall be complied with. However in case of any contradiction same to be resolved in consultation with the Owner/PMC/Licensor.



Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

3.7

AIR COOLED HEAT EXCHANGERS

3.7.1.0

THERMAL DESIGN CRITERIA

3.7.1.1

Design air temperature

3.7.1.2 3.5.1.1.2

Page 27 of 52


:

Type of Draft

:

As per process package

As per basic engineering design basis

Forced

0

TUBE DIAMETER

TUBE THICKNESS

TUBE THICKNESS FOR IBR

TUBE LENGTH

Carbon Steel

25

2.77

2.77

8.5/10.5/12.5 m

Stainless Steel

20

2.11

2.3

8.5/10.5/12.5 m

High alloy Steel

20

2.11

2.3

8.5/10.5/12.5 m

TUBE MATERIAL

Higher tube OD may be used where design constraints exist. 3.7.1.4

Tube Length (TL)

:

If on piperack, TL = piperack width + 0.5m

If on technological structure, suitable tube length shall be adopted.

Note : Standard lengths are 8.5m, 10.5m and 12.5m 3.7.1.5

Fin Data

:

Aluminium “G” type (embedded) fins upto 0 400 C fin design temperature (maximum 9 fins/inch)

3.7.1.6

Width of bundle (Max.)

3.7.1.7

Type of Header :

:

0

3.0 m

Cover Type Header to be used for design pressure < 50 Kg/cm2g and fouling resistance ≥ 2 0 0.0004 Hr m C/K.Cal. For all other cases and H2 service (H2 partial pressure > 7 2 kg/cm g), plug type header to be used. 3.7.1.8

Split Header

:

If inter pass temperature difference exceeds 1100C or if design temperature 0 exceeds 180 C.



3.7.1.9

Page 28 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

Corrosion Allowance

:

3mm for Carbon steel/Low alloy steel NIL for Stainless steel/High Alloy Steel

(Note : Higher/lower value for CA to be considered if specified in process datasheet). 3.7.1.10

As per Process data sheet & P&ID.

Auto-variable fans


Variable speed motors


Provision of Louvre

3.7.1.11

Maximum fan horsepower

3.7.2.0

MECHANICAL DESIGN CRITERIA

3.7.2.1

:

:

40 kW

Bolting (except nozzle bolting)

:

Metric Inch

3.7.2.2

Construction of Header

:

Plate

3.7.2.3

Minimum flange connection size (except Multi-Purpose connection)

:

1 ½” NB

3.7.2.4

Construction of nozzles Upto 12” NB

:

From seamless pipe

14” NB and above

:

When made from plate, weld seam of nozzle to be 100% radiographed

3.7.2.5

Nozzle Flanges

:

Forged weld neck.

3.7.2.6

Multi-Purpose connections

:

One on one of the inlet & one on one of the outlets of each header size 1.5”NB flanged with BF, rating will be same as process nozzle. If it is not possible to provide on process nozzle then it shall be provided on header. One nozzle at inlet and one nozzle at outlet of the shell /channel box to be provided for hydro testing of the shell in addition to MP connection

Note : Any special recommendation regarding vent & drain connection shall be followed as per process data sheet requirement/P&ID’s. 3.7.2.7

Tube to tubesheet joint

:

Expanded (into two grooves) upto design 2 pressure of 70 kg/cm g for non lethal service.

:

For design pressure above 70 kg/cm2g and for lethal service, tube to tubesheet joint shall be “Strength welded with contact expansion”.



Page 29 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

3.7.2.8

Noise Level

:

The noise level shall be limited to 85 dB(A) max. measured at the header access platform walkways and one meter from the bay limit on motor maintenance platform. The noise level within the air cooler bay shall be 90 dB(A) maximum, at locations defined as per API.

3.7.2.9

Positioner for Autovariable fan

:

Integral type positioner shall be provided.

3.7.2.10

Loss of signal air to Auto fan

:

Blades of the fan shall lock in the maximum flow condition unless specified otherwise.

3.7.2.11

Type of Drives (Speed Reducers)

:

HTD/PGGT of GATES or Torque Drive Plus belts of FENNER, UK upto 40 kW.

3.7.2.12

Access Platform

:

Shall be provided wherever possible on all the four sides, (width=900mm) with stair on one side and ladder on other side.

3.7.2.13

Maintenance Platform

:

Shall be provided full length fans/motors (min. width 1000mm).

3.7.2.14

Fan blade material

:

FRP

3.7.3.0

MISCELLANEOUS ASPECTS

3.7.3.1

Spares (Mandatory)

:

400% gasket for header cover & nozzles

200% gasket for plugs

20% plugs

100% belts, 100% bearings

One set of blade for each size/type of fan

20% bolts & nuts for all nozzle with BF & cover plate

One set of diaphragm actuator with positioner for each type of auto variable pitch fan

Additional fan spares (as supplier recommendations).

Motor spares (as per engineering design basis)

Required

3.7.3.2

3.7.3.3

Spares(Additional)

Roof of bundle

:

for

per



Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

3.7.3.4

Page 30 of 52


Hot dip galvanizing structurals

of

air

cooler

:

Not required

Air cooler structurals shall be hot dip galvanised for the following :i.

Plenum chambers, bundle frames.

ii.

Motor suspension structure, fan guards, gratings for stairs and platforms. All bolts/nuts for structures.

iii.

(Main structure and all other surfaces not indicated above shall be given one coat of primer). Note:

Whenever hot dip galvanizing is used, additional hot dip coat shall be provided on the surfaces. 1

3.7.3.5

Final Painting

:

All header boxes shall be finally painted as per JE spec. at vendor’s shop.

3.7.3.6

Protective Covering (for finned tubes) on bundle bottom/top

:

Yes

3.7.3.7

Vendor selection

:

As per Bidder Qualification Criteria

All licensor requirements shall be complied with. However in case of any contradiction same to be resolved in consultation with the Owner/PMC/Licensor.



Page 31 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

3.9

PLATE HEAT EXCHANGERS

3.9.1.0

GENERAL REQUIREMENT

3.9.1.1

Plate heat exchangers shall be designed and fabricated as proprietory equipment meeting the thermal, material and end connections requirement of the data sheet. Vendor shall be fully responsible for all aspects of design and construction of the plate heat exchanger as per the governing code.

3.9.1.2

End nozzles of the exchanger shall conform to ASME B 16.5 standard. Gasket surface for the end connection nozzle shall be suitable for specified gasket compatible soft gaskets between the plate pack shall be provided by vendor meeting fluid compatibility requirement.

3.9.1.3

Endoscopy with VCR and camera control shall be supplied along with the equipment for inspection of plate type heat exchangers.

3.9.1.4

Close circuit cleaning facility to be provided.

3.9.2.0

PROCESS REQUIREMENT

3.9.2.1

In general, the exchanger shall be a single pass, counter flow design to facilitate access to the plate pack for maintenance.

3.9.2.2

The frame of the exchanger shall be designed to permit future installation of a minimum of 20% additional plates.

3.9.2.3

Ports shall be sized so that combined entrance and exit plus nozzle losses do not exceed 30% of the total pressure drop.

3.9.2.4

Vendor shall use the specified fouling factor. If it is not specified in the data sheet, he shall indicate the fouling factor used by him in arriving at the offered design before award of contract. All licensor requirements shall be complied with. However in case of any contradiction same to be resolved in consultation with the Owner/PMC/Licensor.



Page 32 of 52


Date: 10.09.2008

DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

TABLE – 1 DETAILS AND WEIGHT OF COLUMN ATTACHMENTS 1.

Shape factor calculations)

2.

for

:

0.7

Weight of trays (with liquid) to be considered

:

120 kg / m

3.

Weight of plain ladder

:

15 kg / m

4.

Weight of caged ladder

:

35 kg / m

5.

Equivalent projection to be considered for wind load on caged ladder.

:

300 mm.

6.

Distance of platform below each manhole

:

Approx. 1000 mm

7.

Maximum platforms

:

5000 mm.

8.

Projection of platform

:

900 mm up to 1.0 m dia. Column and 1.2 m for column dia.>1m from column insulation surface

9.

1) Equivalent height of platform (for wind load computation)

:

1000 mm.

2) Shape factor for platform

:

1.0

10.

Weight of platforms

:

100 kg/m .

11.

Platform shall be considered as below: Top and bottom

:

All around

Intermediate

:

Half

distance

shell

(for

between

wind

load

consecutive

2

2

TABLE-2 ALLOWABLE STRESS FOR COMBINED LOADING Vessel condition / temperature –type of stresses New or corroded

Conditions Erection New

Operating Corroded

Test Corroded

Temperature

Ambient

Design

Ambient

Longitudinal

KxSxE

KxSxE

0.90xY.P.xE

Longitudinal compressive stress

KxB

KxB

B



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Where S = B = E = K = Y.P. = Note:

Basic allowable tensile stress as per Clause UG 23(a) of ASME SEC.VIII Div.1 ‘B’ value calculated as per clause UG-23 (b) Weld joint efficiency of circumferential weld, depending on extent of radiography. Factor for increasing basic allowable value when wind or seismic load is present. Yield point stress Allowable stresses in skirt to shell joint shall be as per following:

0.49S, if joint is shear type. 0.70S, if joint is compression type.

TABLE- 3 MATERIAL SELECTION CHART The following table gives general guidelines for material selection chart for various pressure parts / non pressure parts of the equipment:-

PRESSURE PARTS DESIGN TEMP.-C

PLATE

PIPE (SEE NOTE 8)

TUBES, SPACERS (SEE NOTE-11)

NON PRESSURE PARTS FORGING (SEE NOTE 12)

BOLTS/ STUDS/ NUTS EXTERNAL (SEE NOTE 13)

STRUCTURAL ATTACHMENT WELDED TO PRESSURE PARTS, BAFFELS, SUPPORTS, TIE RODS, SEALING, SLIDING STRIPS ETC.

INTERNAL PIPES

STUDS BOLTS NUTS INTERNAL

TIE RODS

CRYOGEN IC FROM -254 UPTO -196

SA240 GR.304L, 304, 316,316L 347 (IMPACT TESTED)

SA312 TYPE 304 304L,316, 316L,347

SA213 TYPE 304 304L,316, 316L,347

SA 182,GR F 304,304L,316 347,316L

SA320 GR B8,8C,8T STRAIN HARDENED

ABOVE -196 UPTO –80

SA240 GR.304L, 304, 316,316L 321,347 SA 353/553 GR.A

SA312 TYPE 304 304L,316, 316L,321, 347 SA333GR.8

SA213 TYPE 304 304L,316, 316L,321, 347 SA334 GR.8

SA 182,GR F 304,F304L, F316L,316 321 347, SA522

SA194GR.8, 8C,8T

SAME AS PRESSURE PARTS

SS GRADE SAME AS TUBES



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LOW TEMP. ABOVE -80 UPTO 60

SA 203 GR E IMPACT TESTED (SEE NOTE-1)

SA333GR.3

SA334GR.3

SA350 GR.LF3

SA 320 L7 SA194GR.4 OR GR7

SA 203 GR E

SA333GR.3

SA193GR.B8 SA 194 GR.8

CS KILLED

ABOVE -60 UPTO 45

SA537CL.1 IMPACT TESTED (SEE NOTE-1)

SA333GR.3

SA334GR.3

SA350 GR.LF3

SA 320 L7 SA194GR.4 OR GR7

SA 537 CL.I

SA333GR.3


CS KILLED

ABOVE -45 UPTO -29

SA 516 (ALL GRADES) IMPACT TESTED (SEE NOTE-I)

SA333GR.6 OR GR.I

SA334GR.6 OR GR.I

SA350 GRLF2

SA 320 GRL7 SA194 GR.4 OR GR7

SA-516(INALL GRADES)

SA333GR.6


CS KILLED

ABOVE -29 UPTO 0

SA 516 (ALL GRADES) (SEE NOTE3)

SA 106 GR.B (SEE NOTE 3)

SA334GR.6 OR1 (SEE NOTE 3)

SA105/ SA266 (SEE NOTE 3)

SA-516(INALL GRADES)

SA 106 GR.B

SA-193GR.B8 SA-194GR.8

CS KILLED

IS- 2062 (WELDABLE QUALITY) SAME GRADE AS PRESSURE PARTS

SA-193 GRB7 SA-194 GR2H

INTERMEDIATE TEMPERATURE ABOVE 0 UPTO 343

ABOVE 343 UPTO 427

SA 516 (ALL GRADES),

SA 106GR.B

SA179, SA 210 Gr. A1

SA-105 SA-266,

SA-193B7 SA-194 GR2H

IS-2062 (PLATES)

SA 106GR.B

SA-193GR.B7 SA-194GR.2H

SA 240 TYPE 304L,316, 321 (SEE NOTE 4)

SA-312 TP 304L, 316L, 321 SA-376 TP321

SA-213 TP 304L 316L, 321

SA182F 304L,316L, 321

SA-193B7 SA-194GR2H


SA 106GR.B

SA-193GR.B8 SA-194GR.8

SA 204GR.B

SA335GRP1

SA 209 GR T1

SA182GR.F1

SA193GR.B7 SA194GR.4

SA387GR11 CL.1/CL.2

SA335 GR.P11

SA213 GR.T11

SA182 GR.F11


SA 240 TYPE 304L,316L, 321(SEE NOTE 4)

SA312 TYPE 304L, 316L, 321 SA376 TYPE 321

SA 213 TYPE 304L, 316L, 321

SA182F 304L, 316L, 321


SAME AS PRESSURE PARTS SAME AS PRESSURE PARTS SAME AS PRESSURE PARTS

SAME AS PRESSURE PARTS SAME AS PRESSURE PARTS SAME AS PRESSURE PARTS

SA-193GR.B8 SA 194 GR.8 SA-193GR.B8, B8M SA 194 GR.8, 8M SA-193GR.B8, B8T SA 194 GR.8, 8T

C-V-, Mo (COMML. QLTY) 1%Cr.1/2Mo (COMML. QLTY) SA479 Gr.304L, 316L, 321

ELEVATED TEMPERATURE

ABOVE 427 UPTO 538

SA387GR.11 CL.1/CL.2 SA387GR.12 CL.I/CL.2

SA335P11 SA335P12

SA213T11 SA213T12

SA182GR F11 SA182 GR.F12

SA193 GR.B16 SA194GR.4



SA-193GR.B8 SA 194 GR.8

V/»a-VMo (COMML. QTLY)

ABOVE 427 UPTO 500

SA 240 TYPE 304,316,321 (SEE NOTE 4)

SA312/ SA376 TYPE 304,316,321

SA213TP 304,316,321

SA182F304, 316,321

SA193 GR.B16 SA194GR.4



SA-193GR.B8 SA 194 GR.8 SA 193 GR. B8M SA 194 GR. 8M

SA479Gr. 304L,316L, 321

ABOVE 538 UPTO 593

SA387GR.22 CL.1/CL.2 SA387GR.21 CL.1/CL.2

SA 335 P22

SA213T22

SA182GR F22 SA 336 GR F22

SA193GRB5 SA194GR.3




2%Cr.1 Mo (COMML. QLTY)

ABOVE 500 UPTO 815

SA240 GR.304H, 316H 321H,

A312/ SA376 TYPE 304H, 316H, 321H

SA213 TYPE 304H, 316H,321H

SA182 GRADES 304H, 316H,321H

SA193GRB8 SA 194 GR.8 (STRAIN HARDENED )




SA479Gr. 304H, 316 H, 321 H.

NOTES 1.0

Pressure vessel steel plates are purchased to the requirement of the standard ASME SA-20 which requires testing of individual plates for low temperature service. Carbon steel material is ordered to meet the impact requirements of supplement S5, of standard ASME SA 20. Typical material specification is as follows. SA516 Gr.60 normalised to meet impact requirements per supplement S5 of SA 20 AT -50 oF.

2.0

All permanent attachments welded directly to 9% nickel steel should be of the same material or of an austenitic stainless steel type which can not be hardened by heat treatment.



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DOC.NO. 44LK5100-00-V.02-0001-A4

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3.0

Check for impact testing requirement as per UCS-66 for coincident temperature and part thickness.

4.0

Selection of stainless steel material shall be based on process recommendation / process licensor.

5.0

This table is not applicable for atmospheric / low pressure storage tanks. Materials shall be selected as per API 650 / API 620 as applicable.

6.0

Materials for caustic service, sour service, or sour service + HIC shall be selected based on specific recommendation of process licensor & considering chemical composition, hardness, Vacuum degassing requirements & heat treatment requirements.

7.0

Material for pressure vessels designed according to ASME SEC VIII DIV. 2 shall be given special consideration as per code.

8.0

All pipes shall be of seamless construction.

9.0

Non-ferrous material and super alloys are not covered above and shall be selected based on specific recommendation.

10.0

Material for vessel / column skirt shall be the same material as of vessel / column shell for upper part with a minimum of 500mm.

11.0

All tubes shall be of seamless construction. Materials used for IBR equipment shall meet all requirements of Indian Boiler Regulations.

12.0

SA 336 shall be used for Heat Exchanger non-standard SS/LAS forgings.

13.0

Internal bolting shall be selected on the basis of shell side material solid or clad as follows: SHELL MATERIAL

STUD

NUTS

Carbon steel &up to 1% Cr.

ASTM A 193 Gr B-7

5% Chrome

A 193 Gr B5

A 194 Gr 3

13% Chrome

A 193 Gr B6X

A 194 Gr 6

Stainless Steel

A 193 Gr*

A 194 Gr*

0

ASTM A-194 Gr 2H

0

For low temperatures, min. quality of bolting material shall be as specified for external bolting and shall be improved if shell side materials are better. * Compatible / same grade of SS. All licensor requirements shall be complied with. However, in case of any contradiction same to be resolved in consultation with the Owner/Jacobs



Page 36 of 52


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DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

SECTION B

TRAYS AND TOWER INTERNALS



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DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

1.0

INTENT

1.1

The intent of this specification is to define basis to be followed for Mechanical Design, engineering,. fabrication, inspection/testing, supply and installation (inside the columns at site) of Trays, Packed Column Internals and Tower Packings separately and collectively known as "Internals". For licensed units, in case the requirements specified here are in conflict with licensor's specifications, licensor's requirements shall govern.

1.2

In case of any conflict between various documents, resolution shall be in accordance with the following order of preference: • • •

2.0

Data Sheets/P&lD's/Design Basis Job Specifications Standard Specifications/Engineering Standards.

PROCESS PARAMETERS, DESIGN INTERNALS

CONDITIONS & SELECTION

OF

As per Process Datasheets 3.0

USAGE OF EXISTING INTERNALS For revamp jobs, all "As-Built" drawings of Columns, Tray/Internals as well as Tower Attachments shall be provided by Client, which shall be the basis of revamp to be



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Rev. 0

carried out by Jacobs. However in case drawings provided by Client are not Built", same shall be treated as base document for proceeding further engineering. Wherever drawings of existing internals are not available, internals will be considered including replacement of existing support ring/bolting to suit the new configurations.

"Aswith new bars

All existing internals found adequate with/without any modifications will be retained presuming: (a) (b) (c)

All such internals are in good physical conditions and can be retained. All the existing internals are in good physical condition to permit partial modifications as necessary to make it suitable for revised conditions. No mechanical design checks of existing internals being retained will be carried out unless explicitly asked/required by Client based on operating feed back.

4.0

DESIGN

4.1

Materials

4.1.1

All materials shall conform to those specified in the respective process drawings or data sheets. No substitution of material will be permitted without the written consent of Owner/Jacobs in required formats as per procedure. In case substitution of material is proposed, vendor shall clearly indicate the reasons for requiring such change and give chemical and physical properties of the proposed alternate material with their standard specification number. All the material supplied by vendor shall be new and of first quality supported with mill test certificates. Unless specified in data sheets, Material shall be as per clause from 4.1.2 to 4.1.7.

4.1.2

13 Cr Stainless Internals. All sheet and plate material shall be in accordance with SA 240 Type 410S or 410 or 405 having No.1 finish only for thickness more than 4mm. For thickness up to and including 4 mm, No. 2B/2D finish is also acceptable. All bolting material shall be SA 193 Gr B6X or B6 for bolts and SA 194 Grade 6 for nuts and lock-nuts.

4.1.3

18 Cr - 8Ni Stainless Internals. All sheet and plate material shall be in accordance with SA 240 Type 304 having No. 1 finish only for thickness more than 4mm. For thickness up to and including 4 mm, No. 2B/2D finish is also acceptable. AH bolting material shall be SA 193 Gr B8 for bolts and SA 194 Gr B for nuts and lock-nuts.

4.1.4

Monel Internals



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Rev. 0

All sheet and plate material shall be in accordance with SB127 in hot rolled, annealed and pickled condition. All bolting material shall be Monel, made from rod or bar stock, SB 164. 4.1.5

Carbon Steel Internals Unless otherwise specified, sheets and plates shall be procured in hot rolled conditions and shall be free of mill scale. Material shall be suitable for bending. The bend test specimens shall stand being bent cold through 180 degree without cracking on outside of the bent portion, to an inside diameter equal to or less than twice the thickness of the specimen or as per relevant material specification, whichever is severe. All sheet, plate material shall conform to SA285, SA283 or better unless specified otherwise on the data sheets/drawings. All fasteners including clamps, material shall be as per clause 4.1.2 above, unless specified otherwise.

4.1.6

Gaskets Trays gasketing material shall be woven tape, fabricated from Asbestos Free Material such as Woven Fiber-glass Tape (Amatex-G36-P752 or equal), Woven Teflon Tape, Woven Expanded Graphite Tape or Ceramic Fiber Tape etc. and shall be suitable for process fluid and column design temperature, unless specified otherwise in the Data Sheets/Purchase Specifications. The thickness of the woven tape shall be 1.5 mm minimum. The use of Woven Asbestos Tape or Wire shall be subject to JACOBS/Owner's prior approval only.

4.1.7

Support Rings/Bolting Bars/Support Cleats Support rings, downcomer or up comer bars and other parts welded to vessel shall be of same metallurgy as that of vessel. Minimum thickness excludine corrosion allowance of welded parts shall be 6 mm for vessel diameter up to 3000 mm and 10 mm for higher diameter. Corrosion allowance as specified in vessel data sheets shall be added on both sides of Support Ring, Bolting Bar and other welded parts.

4.2

Thickness of Internals

4.2.1.

Minimum thickness of lnternals: Corrosion allowance, wherever specified in the data sheets for Intemals in excess of corrosion allowance as indicated in clause 4.2.2 shall be added to the minimum thickness specified below:

i)

Deck plates, seal pans, draw-off Pans, weirs/seal plates, other removable Components

ii)

Welded deck plates, downcomer aprons and other welded components

Alloy 2.0

CS 3.5*

3.0

3.5*



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DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

iii)

Downcomer/Internal pipes

2.0

3.5*

iv)

Bubble Caps

1.6

2.0

Risers (fixed)

2.0

3.5*

Risers (removable)

1.6

2.0

v)

Valves

1.6

(will not be used)

vi)

Structured Packings

0.15

(will not be used)

vii)

Support Grid for Structured Packings

5.0

8.0

viii)

Locating Grid/Retaining Grid/Bed Limiter

5.0

8.0

ix)

Grid Packings (a)Bottom-most layer

5.0

8.0

(b)Next Five Layers

2.0

(As per vendor’s standard)

(c)Balance Layers

1.6

(As per vendor’s standard)

x)

Random Packings

xi)

Loose Beams

xii)

Lattice Girders

xiii)

(As per vendor’s standard) To suit Load

To suit Load

(a) Primary Members

5.0

6.0

(b) Secondary Members

3.0

4.0

(c) Gusset Plates

10.0

10.0

(d) Downcomer bolting bars

5.0

10.0

Z-Bars

5.0

8.0

(*10 USSG is also acceptable in lieu of 3.5 mm) All bolting shall be minimum M10 for Internals and M16 for Lattice Girders. All bolt head/nuts shall be hexagonal.



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DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

Minimum corroded thickness of the internals for the loading condition as per Clause 4.3.3. (i) and (ii) below, shall be 3.0 mm. 4.2.2

Corrosion Allowance The following corrosion allowance shall be added to calculate thickness of Internals unless otherwise specified on data sheets or bid specification. i)

No corrosion allowance is required for Monel or Stainless steel alloy assemblies.

ii)

The corrosion allowance for all surfaces of floor of Carbon Steel assembly shall be 1.5 mm (total).

4.2.3

Unless specified on the data sheets or bid specifications, corrosion allowance shall be higher of 1.5 mm (total) or one quarter of the vessel corrosion allowance on each surface of trays and its components.

4.2.4

Beams, trusses and other support members shall have total corrosion allowance equal to vessel corrosion allowance for removable type construction and twice the vessel corrosion allowance for non-removable type construction through vessel man-hole.

4.3.0

Design Loadings

4.3.1

Design loads for tray assemblies shall be based on a liquid height of 50 mm liquid 2 above weirs plus self weight of deck plates and beams or live load of 150 kg/m whichever is severe. In case liquid density is less than water, 1000 kg/m3 shall be considered for purpose of calculating liquid load.

4.3.2

Under-down-flow plates and seal pans shall be designed to withstand a weight of liquid equal to half the normal tray spacing (excluding the locations where tray spacing has been increased to accommodate manholes/feed pipes etc.) or 300 kg/m2 whichever is severe plus self weight of udf plates and beams. In case liquid density is less than water, 1000 kg/m3 shall be considered for purpose of calculating liquid load.

4.3.3

Five trays above/below 2-phase feed inlets and in bottom zone of column wherever process steam or two-phase feed is admitted shall be provided with lock nuts. These trays shall be capable of sustaining a net thrust of 2

i)

1465 kg/m and with shear clips for Vacuum Columns.

ii)

1000 kg/m2 and with shear clips for Crude Column/Main Fractionator Columns.

ii)

450 kg/m for all other services

2

4.3.4

One tray above and below the intermediate vapor/liquid feeds shall also be provided with locknuts.

4.3.5

The packing support plate shall be designed to support the maximum expected load of tower packings, liquid hold-up (min 10 percent). In case of liquid density is less than 3 water. 1000 kg/m shall be considered for purpose of calculating load due to liquid hold-up. Bed limiters frame shall be strong enough to take care of surges/uniformly distributed 2 load of 100 kg/m and 135 kg concentrated load at any point.

4.3.6



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DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

4.3.7

Hold down plate shall exert sufficient static load on the bed to restrict movement of the 2 packing. The hold down plate shall be designed for exerting a load of 100 kglm minimum on the packed bed.

4.3.8

Liquid distributors/Redistributor shall be designed for self weight plus maximum expected liquid load.

4.3.9

All Internals assemblies except cartridge tray assemblies shall be able to withstand the self-weight plus the following number of 135 kg concentrated loads (maintenance loads) at ambient temperature. Vessel Diameter Up to 1200 mm Up to 3600 mm Over 3600 mm

Number of 135 kg loads 1 (at center of diameter) 2 (at center and 1/4 point of diameter) 3 (at center and 1/4< points of diameter)

4.3.10

Design loads for Chimney/Collector trays shall be based on dead weight plus live load of liquid height equivalent to riser height or 50mm more than weir height. In case liquid density is less than water, 1000 kg/m3 shall be considered for purpose of calculating liquid load.

4.3.11

For Chimney trays, layout shall be made in such a way that there will be adequate space available on the tray for a person to get inside and attend to erection of upper trays. Vendor shall check the constructability of all trays with respect to location of man ways, location of down comers and space availability. 0

4.4

Allowable Stress and Deflection

4.4.1

Allowable stresses for all Internals shall be as per ASME Sec. II. Part D, latest edition.

4.4.2

The maximum deflection of tray/tower internal assembly shall not exceed 1 mm per meter of column diameter or 7.5 mm, whichever is lower for the design loadings given in clause 4.3.1 and 4.3.2 above. Deflection for distributor assembly shall be limited so that overall liquid maldistribution does not exceed the limit as per clause 4.5.18(v). Deflection for support plate and seal pans shall be limited to U400, where L is the length of individual component.

4.4.3

Deflection as per clause 4.4.2 may be ignored for trays designed based on design loadings as per clause 4.3.3 and 4.3.9.

4.4.4

For large diameter vessels, initial camber may be made in the principal support members of the assemblies so as to limit the deflection as specified in clause 4.4.2 above.

4.5

Arrangement/Details of Internals

4.5.1

All assemblies except one piece cartridge type trays for column ID less than or equal to 750mm shall be of removable type unless otherwise indicated. The general design, number, type and spacing shall be established on the individual vessel drawing/data sheets. Cartridge type trays shall be designed to rest on four support cleats.

4.52

Each removable section shall be so dimensioned / sized to permit passage through vessel manhole and shall be suitable for assembly/ dismantling from upper side in so far as structural contingencies permit. Maximum diagonal dimension of the components shall be restricted to vessel manhole ID - 12mm clearance.



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DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

4.5.3

Internals support trusses supporting more than one Internal, as are commonly used in large diameter columns and which cannot be installed through manholes, shall be split into sections for access through manhole and minimizing welding work inside the column.

4.5.4

Internals decks shall have a maximum length of 3000 mm. To achieve this maximum distance between main support beams or girders shall be limited to 3000 mm. However, the main support beams or girders having length more than 3000 mm shall be provided with one butt joint with splice plates of the same thickness as the main member up to 6000 mm length and two butt joints with splice plates of the same thickness as the main member for more than 6000 mm length and so on. The butt joint shall be provided inclined at 45 degrees.

4.5.5

Man ways

4.5.6

i)

One man way in single cross flow decks, two man way in double flow decks ' and so on shall be provided. These man way shall be freely removable from top and bottom. Man way shall be in the same vertical line for a set of trays. These shall be at such a location and of a shape and size to permit easy access to every area of the tray. Man way of different set of trays (about 20 trays) shall be staggered to each other. Minimum clear opening on tray shall be 380mm x 450mm. In case same can not be provided due to design conditions, minimum man way size (clear opening) of 360 x 500 or 330 x 550 can be accepted as a special case.

ii)

Where man way cannot be provided, decks shall be split (turn-up - turndown) to provide suitable access for Inspection and assembly from top as well as bottom.

Unless specified otherwise, support rings, bolting bars, support bracket/cleats when required, shall be designed for welding to the vessel. All other parts shall be designed for bolting or clamping in place. Clamping shall be used on Tray floor and all downcomer/up-comer shall be through bolted. Spacing of bolting or clamping shall be close enough to ensure optimum liquid tight construction but shall not exceed 125 mm on deck portion in downcomer area/liquid holding area/downcomer apron bolting etc. and 150 mm in active area. All joints and seams of trays specified to be liquid tight without gasketted joints shall be seal welded at site. Maximum spacing for clamps/bolting for gasketted construction shall be restricted to 100 mm. For revamp jobs, use of Z-Bars shall be maximized to minimize welding/cutting of TSR/BB on the shell, wherever possible.

4.5.7

Drawings and instructions for installation and fabrication of support ring, bolting bar and support bracket/cleats welded to vessel shall be furnished by Internals supplier. They shall show clearly the type, size and extent of welding. All support rings and bolting bars shall be continuously welded on both sides. All support brackets shall be welded all around.

4.5.8

Gasketting need not be used in the design or installation of Internals except for bubble cap trays, all liquid holding portions (e.g. seal pans, draw-offs), collector trays, distributors and redistributors. Fabrication shall provide tight metal-to-metal joints. Metal seal plates shall be used to close construction joints where necessary.



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DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

4.5.9

All stiffeners and support members shall be located on the underside of the tray floor with the exception of open type trusses supporting two trays. Stiffeners and support members in {\ areas shall not exceed 75 mm in width and shall be designed so as not to impede or channel the liquid flow on the tray. Depth of stiffeners and support members transverse and parallel to the liquid flow shall not exceed 20 and 30 percent respectively of tray spacing.

4.5.10

A minimum of 20 mm overlap shall be provided between tray floor section and support members.

4.5.11

Trays and seal pans not specified to be liquid tight, and of a design which would not easily drain shall be provided with one or more 12mm diameter/square drain holes/slots located in the outlet weir directly above the tray flow. Size and number of drain hole/slot may be reduced depending upon liquid rate. Draw off sumps shall be located flush with the invert inside of draw off nozzles to allow complete draining of sumps.

4.5.12

All the three (3) and four (4) pass trays shall have pressure equalizing pipes (vent tubes) across the downcomers.

4.5.13

Bubble Cap Trays Risers Fixed risers shall be used unless otherwise specified in the data sheets. Riser shall be expanded into upward flanged opening in the deck plates and then stitch welded to upturned edges of the opening. Always riser shall not be welded to the bubble cap. 0 Bubble Cap Bubble caps are to be furnished in Full Annealed and scale free bright condition.

4.5.14

Valve Trays Valve assemblies of proprietary trays shall be provided with following features. i) A means of preventing the orifice covers from adhering to tray floor. ii) A means of preventing the orifice covers with integral guide legs and lift stops from popping out of place during operation.

4.5.15

Sieve Trays All perforations shall be punched and made from top side and burr side on tray decks must be downwards when installed, unless specified otherwise. In case of liquid-liquid extractor column trays, punching direction shall depend on the direction of liquid flow of continuous phase.

4.5.16

Burrs shall be removed from all perforated areas and edge of internal sections.



4.5.17

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DOC.NO. 44LK5100-00-V.02-0001-A4

Rev. 0

Distributors/Redistributors Distributors of liquid feed to packed beds, unless otherwise specified in data sheets, shall be gravity flow type (e.g. orifice drip trays, tubed drip trays, trough type, orifice header laterals) in accordance with following requirements: i)

Orifice for liquid distributor shall preferably be minimum 8.4 mm diameter and shall be arranged on an approximate equal spacing throughout the distributor. Distributor supports shall be designed and arranged so as not to interfere with flow from orifices. In case orifice diameter calculated is less than 8.4 mm, then antifouling covers shall be provided on each orifice. Orifice below 6mm diameter shall be preferably provided at an elevation in drip tube or in side of trough with guide tubes.

ii)

Vapor risers shall have a total cross sectional area as per Vendor's design but not less than 15 percent of vessel cross sectional area. Number, size and arrangement of vapour risers shall be such so as not to affect the orifice spacing and liquid distribution to the packings.

iii) Distributor joints shall be gasketted to be liquid tight. Gasket material used shall be suitable for service and soft enough for leak tight joint. iv) iDistributor shall be capable of performing satisfactorily for the range of loadings specified to cover entire range of plant operation. v)

Flow variation from orifice to orifice shall not be more than 10 percent at turndown condition.

vi) Feed pipe shall form part of Distributor supply.

4.5.18

Packing Support Plate Packed bed support plate shall be vapor-injection type, providing separate passage for liquid and vapor flow. The support plate shall have at least 90 percent free area based on cross sectional area of vessel. Slot size shall be so selected to avoid any sneak through of packings from slots.

4.5.19

Bed Limiters/Bed Retainers Bed Limiters/Bed Retainers shall be located just above top of packings to avoid fluidizing of bed and shall be fixed in position so as not to be moved by the packings and shall be designed so as not to affect distribution from the liquid distributor to the packings. Bed Limiters/Bed Retainers for use with spray nozzle distributor shall be designed with major structural support on the underside of the retainer so as not to affect the spray distribution on the packings. Expanded metal with equal opening area is also acceptable in lieu of wire mesh.

4.5.20

Hold Down Plates Hold down plates shall be provided on the top of ceramic or carbon tower packings. The hold-down plate shall directly rest on the bed without any support cleats. Hold-down plate shall exert sufficient static pressure on the bed to restrict movement



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of the bed. Care shall be taken not to use hold-down grid with metallic or plastic tower packings. 4.5.21

Flash Feed Distributor Flash feed distributor for flashing or mixed phase, vapour and liquid feeds to packed bed shall be designed to separate the two phases and distribute the liquid phase on distributor/redistributor. If flashing feed gallery is used, riser area shall be 50% of vessel cross sectional area.

4.5.22

Tower Packing If type of packings is not specified in the process data sheets, following shall be taken as guidelines: i) ii)

iii)

4.5.24

5.0

For wash zone of vacuum column, Grid Packings shall be used. For all other applications preferably Pall Rings shall be used. If pall rings are not expected to perform to desired performance, proprietary random Packings like Intalox saddle of Norton/Koch-Glitsch or similar. If structured packing has been specified, it shall preferably be from the identified source

The maximum allowable pressure drop for a packed bed shall include packed bed support, bed limiter and distributor. FABRICATION AND SUPPLY Tolerances All sections shall be truly flat within 2 mm and shall be tree from burrs and welds spatters. Tolerances wherever unspecified shall be taken as ±1 mm and not to be accumulative, except on thickness and assembly diameter. Tolerances on thickness shall be as per applicable specification and tolerances on assembly diameter shall be as below:

5.2.0

Welding

5.2.1

All welding shall be done by metal arc welding. For welding on thinner gauge sheets TIG welding is preferred.

5.2.2

Gas or Carbon arc welding shall not be used.


5.2.3


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Welding electrodes of composition similar to Internals material shall be used except austenitic electrodes of higher chromium and nickel content such as AWS A5.4, ASME SFA 5.4 class E309 and E310 may be used for 12Cr stainless steel. For dissimilar material welding, electrode composition shall be similar to nobler material being welded. Following electrodes shall be used unless specified otherwise: E 7018

for all CS materials

E308

for all SS 304 to SS 304

E 308L

for all SS 304L to SS 304L

E 309MoL

for SS 410S to SS 410S, SS to CS, SS 410S to SS 304, 304L,316, 3l6L

E316

for all SS316

E316L

for an SS316L

E Ni Cu7

for Monel to Monel and Monel to CS/SS

5.2.4

Welding wherever specified, is to be done by qualified and approved welders using the suitable fillers and fluxes recommended for the materials in the fabrication drawings. For welding the stud on tray decks and support beams, use of stud welding gun with suitable flux is acceptable. In manually welding the studs, care should be taken to minimize the weld spatter and the outside diameter of the weld so that it should not foul with tray deck or washer. For stud welding, proper welding procedure shall be established. Torque required for welding failure shall be higher than the torque required for failure of the stud.

5.2.5

A proposed Welding Procedure Specification (WPS) shall be submitted to AlA for his approval. On approval, a Procedure Qualification Test (PQT) shall be conducted which shall be witnessed by AlA. On acceptance of all tests as per ASME Section IX, a final WPS along with Procedure Qualification Record (PQR) shall be submitted. Production welding shall start only after approval of final WPS/PQR and qualification of welders as per ASME Section IX. AlA may accept previously qualified WPSIPQR at his sole discretion.

5.3

Miscellaneous

5.3.1

All parts fabricated shall be smooth, true, clean and free from burrs, grease and dents. Openings for passage of workman must have exposed edges rounded.

5.3.2

All support rings, bolting bars, beams support brackets and other components which are integral and therefore welded to the column shell inside, shall be supplied and installed by column fabricator.

5.3.3

Total draw-off trays shall be designed for zero leakage construction and may be seal welded (if required) at site to attain zero leakage.

5.3.4

Seal welds shall have a throat thickness at least equal to the specified corrosion allowance.

5.3.5

All stainless steel tray assemblies/internals and their components (e.g. Bubble caps, valves etc.) shall be pickled and passivated. Pickling and Passivation shall be as per ASTM 380.



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5.3.6

All parts shall be fabricated in accordance with good shop practice and in uniformity so that all corresponding parts will be inter-changeable.

5.4

Spares Following spares shall be included as part of the supply:

5.4.1

Constructional Spares The supply shall include the following as constructional spares: Bolts/Nuts

10% of total for each size (Minimum 10 nos. of each size)

Clamp assemblies

10% of total for each type and size (Minimum 10 nos. of each size)

Valves for trays

5% of each type

Bubble caps

5% of each type and size

Gasketing or tapes

100% of each type and size

Sealing foils for cartridge trays

200% of each size

V-clamps

10% of each t ype and size or minimum

10 nos. whichever is

Tower Packings 10% for Metallic and Plastic Packings (Only random packings) 15% for Carbon and Ceramic Packings Spray Nozzles

5.4.2

Up to 25 Nos. (of each type)- 100% More than 25 (or each type) - 25% (subject to minimum of 25 Nos.)

Vendor shall submit list of spares recommended for two years of satisfactory operation. However, following operational spares as a minimum shall be supplied as Mandatory Spares: i. ii.

Valves for Trays Bolts/Nuts

-

iii. iv. v. vi.

Clamp Assemblies Gaskets or Tapes Sealing foils for Cartridge Trays Spray Nozzles

-

vii. Tower Packings

-

10% of each type 10% of total for each type/size (minimum 10 nos. of each size) - do 100% of each type and size 200% of each size 25% subject to minimum 5 Nos. of each type and size. 5% of each type and size. (Only



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Random Packings)

If desired by owner, item wise price for above spares shall be furnished after award of the job. 6.0

INSPECTION AND TESTING

6.1

General

6.1.1

The materials, fabrication, testing and trial assemblies are subject to inspection by Owner/JACOBS, at shop floor before shipment and during installation.

6.1.2

Any rejection made by Inspector shall be final. Approval/Inspection by Jacobs/Owner and/or their designated representative shall in no way relieve the Vendor of his responsibility to meet all the requirements of the Purchase Order.

6.1.3

Owner/Jacobs authorized Inspector shall have free entry to the Vendor's shop at all times where and while the work is being performed. The Vendor shall offer the inspectors all reasonable facilities to satisfy them that the materials are being furnished in accord3nce in accordance with the specifications.

6.1.4

Vendor shall notify the Owner/JACOBS sufficiently in advance of any fabricating operations to permit the Inspector to arrive at the Vendor's shop.

6.2

Stage Inspection during Fabrication

6.2.1

Dimensions The inspector will check that the thickness and the dimensions of all parts for the Decks, Weirs, Seal and Draw off pans, Down comers, Draw off pipes, Supports, Beams, Valves, Bubble caps, Clamps, Studs, Bolts, Nuts, Risers, Washers and Gaskets etc. are as per the approved drawings.

6.2.2

Fabrication The inspector shall check each individual part of the equipment fabricated as per approved drawings and specifications. For instance, for the Bubble cap dimensions, height, width and number of slots, heights, O.D. and I.D. or riser and cap, shroud ring height, exit and inlet weirs height etc. shall be measured. The inspector will check that all identical parts shall be interchangeable. Inspector shall check that the sharp edges on the internal components; man way covers, weirs, downcomers etc. are properly removed. Also that all burrs from punched holes and loose weld slags and materials are removed from all components. Stage-wise inspection during fabrication will be thoroughly carried out. Before starting welding, welders' qualification test will be carried out, if required, as per ASME Sec. IX. Where numbers of similar items are to be made, inspector shall give the clearance for the fabrication of the lot only after checking and approving the first sample piece.

6.3

Trial Assembly



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Trial assembly of one tray of each type and size with its accessories shall be carried out inside the fabricators' shop as floor mock-up. The components for such an assembly will be taken at random from each lot of identical items. The assembled tray will be carefully checked for its dimensions, tolerances, number and arrangement of perforation, the working of the valves in case of valve trays, Vnotch or Blocked Weir, adjustability of weir, vent tube details, downcomer clearance, weir heights, downcomer length and width, number of clamps, gaps and potential leakage points etc. The assembly shall also be checked for each type and size of packed tower internals. Inspector will also check the flatness and deflection of the trays, internals, beams, tray edges and beam ends clearance. Leak Testing Bubble cap, Collector trays, Liquid holding portion of other trays such as Seal pans, Recessed 'seal pans, Draw off pans, Distributors/Redistributors shall be subjected to leakage test at shop floor (by internals vendor) and in the field (by installation contractor) by filling water up to weir level or up to normal liquid level as the case may be. However, in case site installation of these is also included in internals vendor's scope of work, leak testing at shop floor for items in single piece construction is not required. Appropriate ring fixture or a portion of column shell with supports for seal pan/recessed seal pans/draw off box etc. shall be made by Internals Vendor to facilitate leak testing in the shop. Leak testing shall be carried out with service gaskets and drain holes temporarily plugged. All distributors/redistributors shall be leak tested with all holes temporarily plugged. It shall be ensured that leakage is uniform and not from few concentrated places/corners. All plugs shall be removed after leak testing is over. Leakage rate shall not exceed 0.5 percent of design liquid flow rate unless otherwise specified. 6.5

Distributor Testing

-

6.5.1

Vendor's Proprietary Liquid distributors/redistributors shall be water tested in the vendor's shop only by the following procedure at 50%, 100% and 110% of the design liquid volumetric flow rate. The vendor shall certify to the purchaser at the time of bidding that they believe their equipment can meet the testing requirements listed below: (i) If the distributor contains a pre-distributor, it shall be tested first to ensure that it has a CV of 5 or less at the design flow rate. Each orifice in the pre-distributor shall be tested. The CV is defined as the ratio of the standard deviation to the sample mean, expressed as a percent. (ii) The distributor/re-distributor itself shall be tested and the CV determined. To determine the CV, at least 30 pour points or at least 10% of the pour points



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(whichever is higher) shall be randomly selected and tested. If the CV specified below cannot be met, the vendor will correct the problem at its expense. (a) For orifice pans, tubed drip pans and other similar devices, a CV of 10 or less must be achieved at the design liquid volumetric flow rate. (b) Four orifice parts, tubed drip pans or trough distributors that employ a modular (sectional) design, (wherein many pieces are geometrically identical) all pieces of the same geometry shall be treated as one group or strata. One piece from each strata shall then be tested by the procedure outlined above. (c) The average flow rate per pour point for any grouping of 10 of the tested pour points from a single area should differ by no more than 5% from the average for the group or strata being tested. (d) The test results shall be furnished to Jacobs/Owner in a written report. This report shall also contain a drawing of the distributor in plan view. This drawing shall be broken down into 3 radial zones of equal area and the location of pour points sampled in each zone. In case vendor can demonstrate procedure establishing above quality requirements, performance testing of distributors can be waived off. 6.5.2

SPRAY NOZZLE DISTRIBUTORS Spray nozzle distributors shall not be tested in the vendor's shop but must be tested in the tower prior to start-up to ensure that all nozzles are operable and develop the desired spray pattern. This test shall be carried out as close to design rates as possible. SPRAY NOZZLES Apart from the usual material quality tests (chemical analysis and mechanical properties) and manufacturing quality control tests, vendor shall include for & carry out the testing of the spray nozzles with respect to the flow rates for specific ∆P, spray angle, spray coverage and distribution for the tip distance given in the data sheet. The testing medium shall be water. These results shall be, submitted to Owner/JACOBS for review. Tests and acceptance criteria is as below:

7.0

Flow rates Spray angle Flow variation

-

No. of nozzle to be tested

-

±5% for specific ∆P ±50 As per vendor's Standard. (Data to be reported for Information) 10% of each size and type. (Min. 2nos. of each type & size)

SITE INSTALLATION AND SUPERVISION For revamp jobs, cutting & removal of existing attachments, welding of new attachments inside the existing columns and installation of new internals shall preferably be done by column internals supplier. Alternatively, all these activities can be included in the scope of Mechanical Contractor (covered in separate mechanical tender) to have single point responsibility for complete Site Work. In such a case all



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such modifications, installation shall be carried out under the supervision of Internals supplier so as to ensure guarantee of performance of column internals by supplier. For new columns, installation of internals shall be done by column internals supplier only.

JACOBS (HPCL)STANDARD ON PRESSURE VESSEL & HE.pdf

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