Kbr Piping Stress Specification

PTTEP ARTHIT FIELD DEVELOPMENT CENTRAL FACILITIES

PIPING STRESS ANALYSIS SPECIFICATION A-1-PP-PI-SP-0003

CONTRACT NO .

A-TPD 03-0043

This cover page is a record of all revisions of the standard/specification identified above by number and title. All previous cover pages are hereby superseded and are to be destroyed.

B1 A1 R1

13.08.04 15.07.04 25.06.04

APPROVED FOR DESIGN ISSUED FOR APPROVAL INTER-DICIPLINE CHECK

DR DR DR

BM BM BV

ARI ARI ARI

BMK BMK

SOMCHAI

Rev. No.

Date

Purpose of Issue

Prepared By

Checked By

Discipline Approval

Project Approval

Client Approval

PTTEP Arthit Field Development Central Facilities Piping Stress Analysis Specification

Doc. No. A-1-PP-PI-SP-0003

Rev. B1 Page 2 of 23

TABLE OF CONTENTS 1.1 2.0 3.0 4.0 5.0 6.0 7.0 8.0

SCOPE 2 REFERENCE DOCUMENTS, CODES AND STANDARDS 3 OBJECTIVES 5 DEFINITION OF CRITICAL STRESS CATEGORIES 6 STRESS ANALYSIS DESIGN CONSIDERATIONS 8 STRESS DOCUMENTATION 10 PIPE SUPPORT DESIGN 12 NOZZLE ALLOWABLE LOAD CRITERIA (VENDOR SUPPLIED EQUIPMENT, SKIDS 12 AND PACKAGES) 12 NOZZLE LOADS FOR SIZES ABOVE 30” SHALL BE MUTUALLY AGREED BETWEEN COMPANY AND VENDOR. 20 APPENDIX- 3 – WIND LOADING DATA 21 APPENDIX- 4 – TYPICAL RESTRAINT SYMBOLS USED IN STRESS ISOMETRICS22

1.0

INTRODUCTION 1.1

Scope a)

This document defines the method by which piping systems are selected and defined as "Critical" by the Engineering Contractor’s (KBR) Piping




Stress Engineer. Critical lines are those to be stress analysed/reviewed by the Piping Stress Engineer. The term 'piping' referred to in this document is applicable to all of the platform topsides pipe work up to and including the riser ESDV's (Emergency Shutdown Valves) extending up to the hanger flange. The extent of analysis for the topside piping (42” size) riser under PTT scope shall be mutually discussed and agreed. b)

Calculation methods and application of code based procedures for piping stress analysis are defined in this document.

c)

This document also defines the permissible values of nozzle loads imposed by piping on connected mechanical equipment, such as exchanger, pressure vessels and rotating equipment as well as equipment skid package tie-in points.

d)

This specification is applicable for the topsides pipe work for the Arthit Central Facilities which comprises i ii iii iv

1.2

Arthit Central Process Platform (APP) Bridge connecting APP and AQP Bridge connecting APP and AWP1 Flare Bridge with Flare Tower connecting APP to the Flare Tripod

Units All piping calculations, dimensions and weights shall be in Systeme Internationale ( SI ) units.

1.3

Definition The following definitions shall apply to this specification: Company

PTTEP -

Petroleum Authority of Thailand Exploration and Production, Public Company Limited.

Engineering Contractor KBR

-

Kellogg Brown & Root Asia Pacific Pte Ltd

Stress Engineer

-

Engineering Contractor’s Piping Stress Engineer

2.0

REFERENCE DOCUMENTS, CODES AND STANDARDS

2.1

Project Specifications

2.1.1

A-1-PP-PI-SP-0004 – Specification for Spring Support

2.1.2

A-1-PP-PI-SP-0007 – Insulation Specification

2.1.3

A-1-PP-PI-SD-0006 – Pipe Support Standard

2.1.4

A-1-PP-PI-SP-0005 – Pipe Support Design Specification

2.1.5

A-1-PP-PI-LL-0001 – Critical Line List



2.2

Reference Company Documents

2.2.1

AGS-03 – Unfired Pressure Vessels

2.2.2

AGS-05 – Steel Piping Design, Fabrication, and Installation

2.2.3

AGS-08 – Piping Materials

2.2.4

AGS-18 – Site Condition and Climate

2.2.5

AGS-20 – Shell and Tube Heat Exchanger

2.2.6

AGS-21 – Air Cooled Heat Exchanger

2.3

Codes and Standards


Design and analysis of the piping shall be in accordance with following codes. ASME B31.3

Process Piping

ASME B31.4

Pipeline Transportation Systems for Liquid Hydrocarbons and Other Liquids

ASME B31.8

Gas Transmission and Distribution Piping Systems

API RP 14E

Recommended Practice for Design and Installation of Offshore Production Platform Piping Systems

In addition to ASME B31.3, B31.4, B31.8 & API RP 14E and its sub-references, following codes shall also govern the design and installation of some parts of a piping system and the connected equipment. ASME B16.5

Pipe Flanges and Flanged Fittings

ASME B16.47

Large Diameter Steel Flanges

API RP 520

Sizing, Selection and Installation of Pressure Relieving Devices in Refineries Part II - Installation

API RP 521

Guide for Pressure Relieving and Depressurising Systems

API RP 686

Recommended Practices for Machinery Installation Design (Chapter 6 – Piping)

API 610

Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas Industries

API 617

Axial and Centrifugal Compressors and Expander Compressors for Petroleum, Chemical and Gas Industry Services

API 618

Reciprocating Compressors for Petroleum, Chemical and Gas Industry Services.

Installation

and


3.0



API 650

Welded Steel Tanks for Oil Storage

API 660

Shell-and-Tube Heat Exchangers for General refinery Services

API 661

Air Cooled Heat Exchangers for General Refinery Services

API 662

Plate Heat Exchangers for General Refinery Services

UKOOA

Specification and Recommended practice for the use of GRP Piping Offshore

ISO 14692

Specification and Recommended practice for the use of GRE Piping – Piping in the Petroleum or Natural Gas Industries

BS7159

Design and construction of glass reinforced plastics GRP) piping systems for individual plants or sites

BS CP3

Basic data for the design of buildings Chapter V. Loading Part 2. Wind loads

NEMA SM23

Steam Turbines for Mechanical Drive Service.

WRC-107

Local Stresses in Spherical and Cylindrical Shells due to External Loadings

WRC-297

Local Stresses in Cylindrical Shells due to External Loadings on Nozzles – Supplement to WRC 107

OBJECTIVES The objectives for performing stress analysis of piping systems shall include the following. a)

To keep the stresses in the pipes and fittings within the code allowable levels.

b)

To keep the nozzle loadings on the attached equipment within allowable limits of applicable specifications or recognised standards (NEMA SM23, API 610, API 661, etc.)

c)

To minimise vibration of the reciprocating compressor associated piping.

d)

To calculate the design loads for sizing of in-line restraints such as U-bolt, Shoe, Clamp, Trunnion, Guide, Stop, etc., sizing of support frames and selection of spring hangers.

e)

To determine the piping displacements for interference check and prevent excessive sag in piping spans.

f)

To check the leakage at the flange joints.

g)

To prevent unintentional disengagement of piping from its supports.

h)

To help optimize the piping design.



4.0

DEFINITION OF CRITICAL STRESS CATEGORIES

4.1.1

Non-Critical Lines


All metallic, ferrous and non-ferrous lines 2" NB and smaller are deemed noncritical and do not require a formal pipe stress analysis calculation unless specified otherwise. Lines larger than 2” NB that do not fall under any of the criticality criteria listed below shall also be treated as non-critical lines. Some non-critical lines may require special attention, e.g., small branches subject to large displacements and blow down lines. However these lines shall be reviewed / checked for support detail by the stress engineer. 4.1.2

Critical Line List Upon receipt of Piping and Instrument Diagrams (P & ID's), Line List and Piping Specifications, the Stress Engineer shall identify the critical lines and prepare a Critical Line List. These lines require formal pipe stress analysis calculations

4.1.3

Critical line selection A line is defined as critical if it falls into any of the following criticality criteria.

4.2

Criticality Criteria: a)

18" NB and larger

b)

4" NB and larger at 95°C and above

c)

3" NB and smaller at 150°C and above

d)

3" NB and larger at -28°C and below

e)

Alloy, stainless steel and non-ferrous piping 6" NB and larger at 70°C and above

f)

Process lines 4” and above connected to Rotating machinery such as pumps, centrifugal compressors, gas turbines, fans and blowers

g)

All process lines connected to Reciprocating compressors and pumps

h)

All lines process connected to Special items of equipment, which have low allowable loads, specified by the equipment Vendor

i)

All process lines connected to Air-cooled exchangers (fin fans)

j)

All process lines connected to Shell and Tube Heat Exchangers, Plate Heat Exchangers, Printed Circuit Heat Exchangers and Waste heat Recovery Units (WHRU)

k)

Lines subjected to unbalanced surge forces

PTTEP Arthit Field Development Doc. No. A-1-PP-PI-SP-0003 Rev. B1 Central Facilities Piping Stress Analysis Specification Page 7 of 23 l) Lines containing quick acting pressure relieving devices, e.g., relief valves

and bursting discs and blow down valves

4.3

m)

Thick wall pipe, i.e., schedule 160 and above for pipe size 4” & above only

n)

Thin wall, large bore pipe, i.e., schedule 10 and below and 18" and above.

o)

Lines containing expansion devices such as bellows, (only if applicable)

p)

Gas or vapour lines, including the flare system, in which liquid slugs may form and cause high impact loads at valves, bends, tees or vessels.

q)

Lines liable to extreme terminal and support deflections and rotations caused by deck movement

r)

Vacuum and externally pressurised lines , including those liable to transient external pressure conditions.

s)

Liquid blow down piping, not including drain lines.

t)

Lines which the stress engineer considers require special attention but which are not critical by the above definitions.

u)

Riser lines and process lines connected to Launchers / Receivers

v)

All lines running on the platforms linking bridges

Stress analysis method CAESAR II, Verson-4.5 computer program shall be used for stress analysis calculations.

4.4

Piping Studies The Stress engineer shall review and comment on all piping studies pertaining to critical lines. Preliminary pipe support locations shall be identified by piping layout/support section based on good engineering practice considerations, such as span, structure availability and grouping of supports. However the stress engineer shall review and identify, based on the analysis, the final location as well as the type of restraints, such as anchor, directional restraints and springs. Locations of fixed and sliding ends for horizontal vessels and equipment shall be defined by Stress engineer in consultation with other applicable disciplines, Mechanical, Structural etc., as appropriate.


5.0



STRESS ANALYSIS DESIGN CONSIDERATIONS

5.1

Analysis shall be carried out at the design ( max and/or min) temperatures and coincident Design pressure conditions of the selected lines. Where this will lead to an over-conservative design, operating conditions (operating temperature and pressure) of the system shall be used in the analysis. The ambient temperature shall be 36°C maximum and 22°C minimum as per section 4.0 of AGS-18 and solar radiation metal temperature shall be 80°C.

5.2

Support friction shall be considered for the analysis, and the coefficient of friction shall be taken as 0.3, for steel to steel surface contact. For supports in the vicinity of nozzle loads sensitive equipment such as pumps and compressors, a low friction coefficient of 0.1 may be considered if required and the sliding unit (PTFE) to achieve the low friction shall be provided at the support base. Friction factor shall be suitably considered for the combination of sliding surfaces.

5.3

Equipment nozzle shall be modelled as anchor with initial thermal movements. If the calculated reaction loads exceed the allowable values for the nozzles, the nozzles shall be modelled as flexible nozzles

5.4

Piping to and from relief devices shall be designed and/or supported/braced to ensure that exhaust reaction loads, or moments, do not exceed that permitted by the relief valve manufacturer, the equipment manufacturer or the piping code. Bracing of the inlet line to the outlet line is not permissible.

5.5

Stress analysis of piping systems connected to rotating equipment such as pumps shall consider all probable scenarios of operation such as operation and standby etc. Future piping connections, wherever possible, shall also be included in the analysis. Large Pumps require particular attention with regard to nozzle loads. Requirements of large pumps are generally similar to those for compressors.

5.6

For compressor piping, design temperatures shall generally be used to establish pipe thermal expansion for nozzle load purposes. Values should be discussed and agreed with the Process dept. Pipe routing should allow for restraints to be located in line with the machine axes, to effectively cancel expansion forces on the nozzle. Adjustable stops and guides must be provided in both horizontal planes to assist with alignment. Weight supports other than springs shall similarly be adjustable. Spring supports if required shall be constant force type or long range variable and to be very close to the machine, to allow accurate pipe positioning during the alignment process. A piping system entirely supported on springs shall be avoided. The weight run on which spring design is based shall be made with the compressor nozzle disconnected vertically in order to transfer minimum loads to the nozzle. Restraint with guide and stop local to the anti-surge or recycle valve shall be added to avoid vibration due to gas turbulence. Pipe support designs shall be reviewed by Engineering Contractor’s structural engineer to ensure that stress requirements have been complied with.


5.7



Bridge piping Three bridges are linked to Arthit Central Process Platform APP. Location of the bridges fixed and sliding ends shall be confirmed and bridge piping configurations to be reviewed to assess the requirement of expansion loops. Also settlements of platforms and longitudinal & lateral movements shall be considered for bridge piping stress analysis when connected to the existing platform piping. The three bridges are: a) b) c)

5.8

Bridge connecting APP and AQP Bridge connecting APP and AWP1 Flare Bridge with Flare Tower connecting APP to the Flare Tripod

Output shall be scrutinised for a) Stress check for code compliance in sustained, expansion and occasional cases. b) Load check for nozzle allowable values for connected equipment specified in section 9.0 -“Nozzle allowable load criteria” c) Support reaction loads for pipe supports design. d) Excessive piping displacements for interference check and sagging. 5.9

Load Cases

a)

Operating case: This shall include effects of pressure, temperature, pipe dead weight, insulation weight, weight of the contents and other externally imposed displacement such as nozzle displacements etc. This load case is required to be performed to establish that the operating condition loads on the equipment nozzle and pipe supports are within safe limits.

b)

Sustained case: This shall include only the effects of pressure, pipe dead weight, insulation weight and weight of contents. This case is required to be done mainly to check if the code compliance requirements of sustained stresses are satisfied by the piping system.

c)

Expansion case: This shall include effects of temperature and externally imposed displacements such as nozzle displacements etc. This case is for verifying the code compliance requirements of expansion stresses.

d)

Occasional case: This shall include effects of wind, wave load (if any), and pressure relief valve reaction forces, each should be analysed independently. As per provision of ASME B 31.3, no two occasional load cases need to be considered simultaneously for compliance requirements. This case is required for getting additional loads transferred by occasional forces to structure at pipe supports, guides, nozzles, anchor locations and also for verifying code compliance requirements of occasional stresses. For wind loading data refer Appendix-3.

e)

Slug load case: Liquid slugs entrained in flowing gas exert a force on any change of direction or change in pipe size. The velocity and specific gravity values have a profound effect upon calculated loads and realistic data must be agreed with the Process Dept. Forces acting at a change of direction may be evaluated by consideration of momentum change or centrifugal force. A dynamic amplification factor of 2.0 (max) shall be considered




unless specified otherwise which is dependent on velocity and piping component type. This case is required to be done mainly to design the pipe support structure for slug load and to check the stress in the piping system due to slug load. f)

Hydrostatic test case: This is to verify the stress occurring during testing as well as to establish the maximum loads that need to be supported by the designed pipe support/structure.

g)

Surge case analysis: Surge analysis as applicable and as required will be carried out by the third party agency. The unbalanced forces as provided by the surge specialist will be used in the CAESAR analysis to calculate the stress and support loads.

h)

Blast load case: Analysis shall be carried out as applicable. The drag forces as provided by the Safety group will be used in the CAESAR analysis to asses the stress and support loads. Transportation Case: Separate transportation analyses shall be carried out taking in to account the effect of barge motion (acceleration) and the deck new set of deflections. Based on the results, recommendations will be provided for piping disconnections from the equipment nozzles to avoid any overloading.

Appendix-1 shows load cases to be built up in CAESAR. 6.0

STRESS DOCUMENTATION

6.1

Stress calculation (CAESAR file) Numbering Stress calculation input files should be numbered as follows: Example: ACF1101NAD1 Where ACF Arthit Central Facilities The first digit of the 4 digit number shown in box is allocated as follows. 1 2 3 4 5

Arthit Central Process Platform (APP) Bride connecting APP and AQP Bridge connecting APP and AWP1 Flare Bridge with Flare Tower connecting APP to the Flare Tripod Arthit living Quarters Platform (AQP)

The last three digits are allocated as follows: 000 to 099

Separation Piping including incoming/outgoing Riser Lines, Headers and Produced Water Piping

100 to 199

Mercury Removal System Piping

200 to 299

Feed Gas Compression Piping



300 to 399

CO2 Removal System Piping

400 to 499

NGL Extraction Piping

500 to 599

Sales Gas Compression Piping

600 to 699

Condensate Stabilization Piping

700 to 799

VRU Compression Piping

800 to 899

Fire Water Piping

900 to 999

Utility and other Piping

NA,NB, etc.,

Normal case Calculation sequence

BA,BB, etc.,

Blast case Calculation sequence

TA,TB, etc.,

Transportation case Calculation sequence


R1, D1, D2 etc., Revision number 6.1

Preparation of Stress Isometrics Stress isometrics will be extracted from PDMS and they shall be numbered as follows. ACF-STISO-1101 The four digit number shown as a last entry in the above numbering shall be same as the four digit number used for the stress calculation file. All restraints acting on the piping shall be clearly indicated using standard legends found in Appendix-4. Sufficient nodes must be shown to allow a third party to navigate around the system when reading the drawing in conjunction with a CAESAR II input listing.

6.2

Master Stress Isometrics A master file of stress isometrics shall be maintained and agreed changes signed and dated.

6.3

Input file Handling Input files shall be electronically archived on completion of each calculation. Only the files with a _A and _J trailer need to be kept and backed up on the ‘O’ drive. A record of files archived shall be maintained.

6.4

Stress Analysis Report The Stress Analysis Report will be compiled after all Fabrication isometrics for the stress critical lines have been issued. It is intended to provide evidence of all work completed by stress engineer in selection, analysis and approval of critical lines.




The preferred format of stress analysis report is as follows: Contents, Summary and calculations, system and analysis description, Critical line list and stress isometric index, stress iso, data and calculations, General and calculations. The preferred format is to exclude computer output from CAESAR II and to supply with disc copies of all input files from which output can be generated if required. 7.0

PIPE SUPPORT DESIGN Stress engineer shall review in-line support details. The review must ensure that the supports and restraints are fit for purpose, for example whether restrained along the correct axes, support requirement for concentrated loads Standard support details shall be used wherever possible to suit the deck steel work. Pipe support with spring hanger shall only be used where all other possible design solutions have been exhausted. Spring design data sheets shall be completed by the stress engineer and the necessary input such as elevation details shall be provided by the pipe supports group.

8.0

NOZZLE ALLOWABLE LOAD CRITERIA (Vendor supplied Equipment, Skids and Packages)

8.0.1

The allowable forces and moments stated in this specification apply directly to steel equipment and at the tie-in interfacing nozzle flange face whereas for Pressure vessels and Shell & Tube Heat Exchangers, the loads are applicable at nozzle/shell intersection.

8.0.2

For Titanium equipment, the allowable loads shall be 70% of the load values given in Appendix-2 or as agreed with the vendor.

8.0.3

For Cupro-Nickel equipment, the allowable loads shall be 50% of the load values given in Appendix-2 or as agreed with the vendor.

8.0.4

For other materials including GRP, the Vendor shall provide an appropriate set of calculations for review and approval.

8.0.5

A statement of compliance, with this Specification, shall be provided by the Vendor.

8.0.6

The piping loads contained in this specification apply to design conditions only. If the nozzle design loads exceed the allowable limit, when the piping is designed for occasional load cases, such as, wind, wave, PSV forces and occasional slugging, these loads will be submitted for Vendor’s approval during the detail design phase.

8.1

Centrifugal Pumps The allowable forces and moments on pump nozzles due to piping reactions shall be two times the values given in table-4 of API 610, 9th Edition for nozzle sizes 16” and below. This also applies to ‘Vertical In-line’ pumps and ‘Horizontal/Vertical Suspended’ pumps.




Nozzle loads on Horizontal End Suction Centrifugal Pumps and Vertical In-Line Centrifugal Pumps in accordance with ASME B73.1 and B73.2 shall also be two times the values given in table-4 of API 610, 9th Edition. Should there be a requirement for increased nozzle allowable forces or moments in any one or more directions at the detailed engineering stage, the same shall be mutually discussed and agreed between the Vendor and Company. For pump nozzle sizes above 16”, Company will provide the forces and moments at the pump nozzles based on the stress analysis of the system for review and acceptance by the vendor. 8.2

Centrifugal Compressors & Turbo Expander Compressors The loads on Centrifugal Compressor and Turbo Expander Compressor nozzles shall be in accordance with NEMA SM23 Section 8.4.6 formulae; however the constants in formulae shall be increased by a minimum factor of 4 Should there be a requirement for increased nozzle allowable forces or moments in any one or more directions at the detailed engineering stage, the same shall be mutually discussed and agreed between the Vendor and Company. Net resultants of combined forces and moments shall be resolved at the suction (larger) nozzle in the case of a two-nozzle machine. The equivalent nozzle diameter Dc shall be based on the nominal nozzle outside diameters.

8.3

VRU System Reciprocating Compressor Package Vendor shall inform the desired minimum mechanical natural frequency to be established for the entire VRU piping system starting from suction scrubber inlet lines up to the discharge scrubber outlet lines. The piping within VRU compressor package shall be supported and guided, as necessary, and the interface tie-in points shall be anchored by the vendor such that the interface nozzle shall be designed to satisfy the ‘Forces and Moments’ stated in Appendix-2. For some reasons, if it is not possible for vendor to provide anchor at the interface tie-in points, then the vendor shall provide stiffness values and thermal movements at the compressor nozzles in all degrees of freedom (3 translations and 3 rotations). Engineering Contractor will provide loads (forces and moments) imposed by piping at the compressor nozzles based on the stress analysis of the complete system for review and acceptance by the vendor.

8.4

Pressure Vessels, Columns, Filters and Pig Launchers / Receivers

8.4.1

External loads applied to Pressure vessels and columns nozzles shall normally be limited to the values given in Appendix-2 of Arthit General Specification AGS-03 (Unfired Pressure Vessels)

8.4.2

In the event that a component force or moment due to piping reactions exceeds the respective allowable but the resultant remains within the resultant allowable, WRC107 / WRC297 calculation may be performed by the Company to accept the loads. In case the WRC calculation fails, Company will modify the piping and/or restraints to limit the loads within the values given appendix-2 of AGS-03. If this is




not achievable by the Company, the loads will be provided to the vendor. Vendor shall re-analyse the vessel for new loads to verify and ensure that all stresses are still within the allowable limits with suitable modification if any on the vessel. 8.4.3

If component and resultant exceed the allowable loads, piping and / or restraints will be modified to comply with values given in Appendix-2 of AGS-03. If this proves to be impractical, Company will provide the loads for review and acceptance by the vendor for suitable modification if any on the vessel.

8.4.4

The locations and loading for pipe support clips on the vessel and/or service platform will be furnished separately during the detailed engineering stage which shall be verified by the Vendor for the stresses and other aspects of vessel and service platform design.

8.5

Shell & Tube Heat Exchangers, Double Pipe Type Heat Exchangers, Plate Type Heat Exchangers & Printed Circuit Heat Exchanger External loads applied to nozzles of shell & tube heat exchangers, Double pipe type heat exchangers, Plate type heat exchangers and Printed circuit heat exchangers shall normally be limited to the values given in Appendix-2. External Forces and Moments given in Appendix-2 are to be applied at nozzle / shell intersection simultaneously. Sections 8.4.2, 8.4.3 & 8.4.4 are applicable here also.

8.6

Air Cooled Heat Exchangers Allowable loads shall be three times the values given in API 661 Table 4. Should there be a requirement for increased nozzle allowable forces and moments in any one or more directions at the detailed engineering stage, the same shall be mutually discussed and agreed between the vendor and Company. If pipe support clips are required on the cooler service platforms, locations and loadings for the clips will be furnished separately during the detailed engineering stage which shall be verified by the Vendor for the stresses and other aspects of platform design.

8.7

Tanks Unless agreed with Company, the allowable nozzle loads for flat –sided storage tanks are as tabulated below. Table-A ( Metric Units ) Nozzle Size 1 ½” 2” 3” 4” 6” 8” Notes:

Direct Loads (N) F Axial 750 750 1500 2000 3000 3500

F Shear 750 750 2000 3000 5000 6000

Moment Loads (N-m) M Torsion 150 150 750 1400 3000 4500

M Bending 150 150 450 750 2000 3000


8.8



1)

All loads stated above act at the tank plate / nozzle intersection and are to be assumed to act simultaneously.

2)

The Vendor shall provide sufficient local reinforcement to ensure that the stress due to pressure head, radial load and applied moment does not exceed 1.5 times the allowable design stress for the plate.

3)

For nozzles exceeding 8” N.B, allowable loads shall be agreed with the Company. Waste Heat Recovery Unit Based on the analysis, Engineering Contractor will provide loads (forces and moments) imposed by piping at Heating Medium inlet and outlet nozzles of Waste Heat Recovery Unit (WHRU) for review and acceptance by the Vendor.

8.9

Packaged Units

8.9.1

Package unit Vendor shall furnish the list of lines considered for stress analysis for Company’s review. Stress analysis for Package unit piping carried out by vendor shall be as per this specification as a minimum.

8.9.2

When the piping is connected to equipment other than that specified in this Specification, the loading listed in Appendix-2 shall be used.

8.9.3

The Vendor shall anchor all package piping at the skid edge. Where this proves impractical, the Vendor shall advise the Company no later than six weeks after award of the contract. The piping within the package shall be supported and guided, as necessary, by the Vendor such that the interface nozzle shall satisfy the ‘Forces and Moments’ stated in Attachement-2. The Vendor shall provide isometric drawings showing all pipe support restraints.

8.9.4

For terminations anchored at a skid edge, the allowable external loading (from piping outside the package) will correspond to the ‘Forces & Moments’ stated in Appendix-2. Tie-in anchor, at the Vendor/Company interface, shall be capable of withstanding two times the values as per Appendix-2.

8.9.5

Should there be a requirement for increased allowable forces or moments in any one or more directions at the detailed engineering stage, the same shall be mutually discussed and agreed between the Package Unit Vendor and Company.

8.10

Tie-ins between Topsides and Risers For riser connected topsides piping, “Hanger Flange’ shall be treated as an anchor for carrying out topsides piping stress analysis. The forces and moments due to topsides piping shall be taken into account for hanger flange design.

8.11

Flange joints




Supports are to be provided close of flange joints, where heavy concentrated loads occur. A review will be done by the stress engineer for these types of supports. Pressure design of flanges shall generally be in accordance with section 304.5 of ASME B31.3. Operating pressure shall be considered for the purpose of flange leak calculation. Piping stress analysis programme CAESAR II shall be used for checking the flange leakage. 8.12

Vendor Drawings and Data The stress section shall review and comment on all Vendor drawings, such as, equipment and vessels, pertaining to connected stress critical piping. Review shall include interface tie-in connection drawings and details for Package/skid units, pertaining to stress critical lines.

APPENDIX-1 – CAESAR LOAD CASES




NORMAL CASES 1 2 3 4 5 6 8 9 10 11 12 13

ASME B31.3 Stresses, Nozzle Loads , Restraint Loads & Hydro-test Restraint loads Simple System System with added PSV Forces System with Spring Hangers W+D4+T1+P1 (OPE) 1 W+D4+T1+P1+F1 (OPE) 1 W (HGR) W+P1 (SUS) – B31.3 Stresses 2 W+P1+F1 (OPE) 2 W+D4+T1+P1 (HGR) WIN1 (OPE) 3 W+P1 (SUS) – B31.3 Stresses 3 W+D4+T1+P1+H (OPE) WIN2 (OPE) 4 WIN1 (OPE) 4 W+P1+H (SUS) – B31.3 Stresses WW+HP (HYD) – Hydro-test Loads 5 WIN2 (OPE) 5 WIN1 (OPE) L2+L3 (OCC) B31.3 Stresses 6 WW+HP (HYD) – Hydro-test Loads 6 WIN2 (OPE) L2+L4 (OCC) 7 L2+L4 (OCC) B31.3 Stresses 7 WW+HP (HYD) – Hydro-test Loads L1+L3 (OPE) Nozzle & 9 L2+L5 (OCC) 8 L4+L5 (OCC) B31.3 Stresses L1-L3 (OPE) Restraint 10 L1+L4 (OPE) Nozzle & 9 L4+L6 (OCC) L1+L4 (OPE) Loads 11 L1-L4 (OPE) Restraint 10 L3+L5 (OPE) Nozzle & L1-L4 (OPE) 12 L1+L5 (OPE) Loads 11 L3-L5 (OPE) Restraint L1-L2 (EXP) – B31.3 Stresses 13 L1-L5 (OPE) 12 L3+L6 (OPE) Loads 14 L1-L2 (EXP) – B31.3 Stresses 13 L3-L6 (OPE) 14 L3-L4 (EXP) – B31.3 Stresses Hydro-test load case shall be run separately with Springs replaced by Rigid hangers.

BLAST CASE Stresses & Restraint Loads

1 W+D4+T1+P1 (OPE) 2 W+P1 (SUS) 3 BLAST – X (OCC) 4 BLAST – Y (OCC) 5 BLAST – Z (OCC) 6 L1+L3 (OPE) 7 L1-L3 (OPE) Restraint 8 L1+L4 (OPE) Loads 9 L1-L4 (OPE) only 10 L1+L5 (OPE) 11 L1-L5 (OPE) 12 L2+L3 (OCC) 13 L2-L3 (OCC) Stress Check, 14 L2+L4 (OCC) Allowable = 15 L2-L4 (OCC) Yield 16 L2+L5 (OCC) 17 L2-L5 (OCC)

TRANSPORTATION CASE B31.3 Stresses, Nozzle & Restraint Loads

WNC+D1+D2+D3+U1+U2+U3(SUS)

SLUG CASE This case is similar to Normal case with added forces. The added forces are Slug forces at pipe elbows.

SURGE CASE This case is also similar to Normal case with added forces. The added forces are Surge forces at pipe elbows. If the system has to be designed for the effect of surge at one elbow at a time, then as many number of cases as the number of elbows in the system have to be analysed to determine the worst loads.

W-

Pipe Weight, Insulation Wt, Fluid Wt, Rigid Wt WW - Pipe Weight, Insulation Wt, Water-filled Wt, Rigid Wt WNC - Pipe Weight, Insulation Wt, Rigid Wt P1 Design or Operating Press. HP Hydrostatic Test Pressure T1 Design or Operating Temp. D1,D2 - Deck deflections during & D3 transportation D4 Anchor Thermal Movement F1 Applied Forces or Moments H Hanger Load WIN1 - X direction Wind Pressure WIN2 - Z direction Wind Pressure BLAST - Blast Forces in X,Y,Z - X,Y,Z Directions U1,U2 - Acceleration during & U3 transportation OPE SUS OCC EXP HYD HGR

- Operating (No code stress check) - Sustained case - Occasional case - Expansion case - Hydro-test case - Hanger Load case




APPENDIX-2 – EXTERNAL FORCES AND MOMENTS ON NOZZLES Nozzle Size (in)

Flange Rating (psi)

2” and below

Forces, N

Moment, N-m

FL (Longi.)

FC (Circum.)

FA (Axial)

FR (Resultant)

ML (Longi.)

MC (Circum.)

MT (Torsional)

MR (Resultant)

150 300 600 900 1500 2500

1,225 1,225 1,820 1,820 2,205 2,205

1,225 1,225 1,820 1,820 2,205 2,205

1,000 1,000 1,485 1,485 1,800 1,800

2,000 2,000 2,975 2,975 3,600 3,600

250 250 335 335 375 375

250 250 335 335 375 375

350 350 470 470 530 530

495 495 665 665 750 750

3”

150 300 600 900 1500 2500

1,850 1,850 2,500 3,500 4,535 4,535

1,850 1,850 2,500 3,500 4,535 4,535

1,510 1,510 2,045 2,855 3,705 3,705

3,020 3,020 4,085 5,710 7,405 7,405

585 585 755 975 1,160 1,160

585 585 755 975 1,160 1,160

825 825 1,070 1,380 1,645 1,645

1,170 1,170 1,510 1,955 2,325 2,325

4”

150 300 600 900 1500 2500

2,635 2,635 3,655 4,640 6,720 6,720

2,635 2,635 3,655 4,640 6,720 6,720

2,150 2,150 2,985 3,785 5,450 5,450

4,300 4,300 5,940 7,575 10,975 10,975

1,090 1,090 1,450 1,760 2,305 2,305

1,090 1,090 1,450 1,760 2,305 2,305

1,540 1,540 2,050 2,485 3,260 3,260

2,180 2,180 2,900 3,515 4,610 4,610

6”

150 300 600 900 1500 2500

4,630 5,630 6,975 8,880 12,975 13,150

4,630 5,630 6,975 8,880 12,975 13,150

3,780 4,600 5,695 7,250 10,595 10,740

7,560 9,200 11,390 14,505 21,185 21,475

2,880 3,440 4,145 5,080 6,795 6,860

2,880 3,440 4,145 5,080 6,795 6,860

4,075 4,860 5,865 7,185 9,605 9,700

5,765 6,880 8,295 10,160 13,585 13,720

8”

150 300 600 900 1500 2500

6,970 7,425 8,700 14,820 19,600 21,880

6,970 7,425 8,700 14,820 19,600 21,880

5,690 6,060 7,100 12,100 16,005 17,865

11,380 12,125 14,205 24,200 32,005 35,725

5,385 5,710 6,595 10,455 13,020 14,110

5,385 5,710 6,595 10,455 13,020 14,110

7,615 8,075 9,325 14,785 18,415 19,950

10,770 11,420 13,190 20,910 26,045 28,215

10”

150 300 600 900 1500 2500

9,880 13,360 15,730 21,795 28,075 33,250

9,880 13,360 15,730 21,795 28,075 33,250

8,070 10,910 12,840 17,795 22,920 27,150

16,135 21,820 25,680 35,595 45,845 54,300

9,020 11,895 13,760 18,210 22,315 25,315

9,020 11,895 13,760 18,210 22,315 25,315

12,755 16,820 19,460 25,755 31,555 35,800

18,040 23,780 27,520 36,425 44,630 50,625




APPENDIX-2 – EXTERNAL FORCES AND MOMENTS ON NOZZLES (Contd) Nozzle Size (in)

Flange Rating (psi)

Forces, N

Moment, N-m

FL (Longi.)

FC (Circum.)

FA (Axial)

FR (Resultant)

ML (Longi.)

MC (Circum.)

MT (Torsional)

MR (Resultant)

12”

150 300 600 900 1500 2500

12,100 17,880 21,635 30,630 40,330 46,085

12,100 17,880 21,635 30,630 40,330 46,085

9,880 14,610 17,665 25,010 32,930 37,630

19,755 29,200 35,330 50,020 65,860 75,255

12,390 17,760 21,100 28,460 35,470 39,170

12,390 17,760 21,100 28,460 35,470 39,170

17,520 25,110 29,840 40,250 50,160 55,395

24,780 35,515 42,200 56,925 70,940 78,340

14”

150 300 600 900 1500 2500

13,320 15,485 25,905 36,805 51,235 74,940

13,320 15,485 25,905 36,805 51,235 74,940

10,875 12,640 21,150 30,050 41,830 61,185

21,795 25,285 42,300 60,095 83,665 122,370

14,050 16,200 25,905 35,060 45,585 58,935

14,050 16,200 25,905 35,060 45,585 58,935

19,870 22,895 36,635 49,580 64,465 83,345

28,100 32,375 51,810 70,115 91,170 117,870

16”

150 300 600 900 1500 2500

15,275 20,200 33,345 46,965 63,795 90,815

15,275 20,200 33,345 46,965 63,795 90,815

12,470 16,495 27,225 38,345 52,085 74,145

24,940 32,985 54,455 76,690 104,170 148,290

17,215 22,415 35,445 47,660 60,940 78,065

17,215 22,415 35,445 47,660 60,940 78,065

24,340 31,700 50,125 67,405 86,180 110,400

34,425 44,830 70,890 95,325 121,880 156,130

18”

150 300 600 900 1500 2500

17,230 25,545 41,715 59,585 80,660 114,140

17,230 25,545 41,715 59,585 80,660 114,140

14,065 20,885 34,060 48,650 65,855 93,195

28,130 41,715 68,120 97,295 131,710 186,385

20,270 29,435 46,110 62,770 80,030 102,155

20,270 29,435 16,110 62,770 80,030 102,155

28,665 41,630 65,210 88,770 113,180 144,465

40,535 58,870 92,220 125,540 160,065 204,310

20”

150 300 600 900 1500 2500

18,435 26,715 45,320 64,305 82,275 121,405

18,435 26,715 45,320 64,305 82,275 121,405

15,050 21,810 37,005 52,505 67,175 99,125

30,105 43,620 74,005 105,010 134,345 198,250

24,875 35,370 57,455 77,820 95,085 125,905

24,875 35,370 57,455 77,820 95,085 125,905

35,175 50,020 81,250 110,055 134,465 178,055

49,745 70,745 114,910 155,645 190,165 251,810

22”

150 300 600 900 1500 2500

19,140 27,080 47,600 67,110 91,840 131,245

19,140 27,080 47,600 67,110 91,840 131,245

15,630 22,110 38,865 54,795 74,895 107,155

31,260 44,215 77,730 109,585 149,970 214,310

29,550 41,100 69,050 93,060 119,915 154,425

29,550 41,100 69,050 93,060 119,915 154,425

41,790 58,120 97,650 131,605 169,585 218,390

59,105 82,200 138,100 186,120 239,830 308,855

150 300 600 900 1500 2500

20,420 27,870 48,255 69,865 92,405 133,390

20,420 27,870 48,255 69,865 92,405 133,390

16,670 22,755 39,400 57,040 76,260 108,905

33,340 45,510 78,800 114,085 152,520 217,810

36,030 48,420 80,220 110,590 139,770 179,995

36,030 48,420 80,220 110,590 139,770 179,995

50,955 68,475 113,445 156,400 197,660 254,550

72,065 96,840 160,440 221,180 279,535 359,990

24”




APPENDIX-2 – EXTERNAL FORCES AND MOMENTS ON NOZZLES (Contd) Nozzle Size (in)

Flange Rating (psi)

Forces, N

Moment, N-m

FL (Longi.)

FC (Circum.)

FA (Axial)

FR (Resultant)

ML (Longi.)

MC (Circum.)

MT (Torsional)

MR (Resultant)

26”

150 300 600 900 1500 2500

22,370 31,930 52,205 80,330 108,550 154,375

22,370 31,930 52,205 80,330 108,550 154,375

18,265 26,070 42,625 65,585 88,630 126,045

36,525 52,140 85,250 131,170 177,255 252,085

42,460 59,600 93,920 136,995 174,935 225,250

42,460 59,600 93,920 136,995 174,935 225,250

60,045 84,285 132,820 193,740 247,390 318,545

84,915 119,195 187,840 273,990 349,865 450,495

28”

150 300 600 900 1500 2500

25,305 35,855 59,555 91,225 121,815 175,360

25,305 35,855 59,555 91,225 121,815 175,360

20,660 29,275 48,625 74,480 99,460 143,175

41,320 58,545 97,245 148,960 198,915 286,350

51,780 72,195 115,560 168,090 212,940 277,540

51,780 72,195 115,560 168,090 212,940 277,540

73,225 102,100 163,420 237,710 301,140 392,495

103,560 144,390 231,115 336,175 425,880 555,075

30”

150 300 600 900 1500 2500

28,415 40,980 65,455 98,240 137,870 197,605

28,415 40,980 65,455 98,240 137,870 197,605

23,200 33,460 53,440 80,210 112,565 161,335

46,400 66,920 106,880 160,420 225,130 322,670

62,350 88,435 136,630 195,785 259,005 337,190

62,350 88,435 136,630 195,785 259,005 337,190

88,175 125,065 193,220 276,875 366,285 476,855

124,700 176,870 273,255 391,565 518,010 674,380

Nozzle Loads for sizes above 30” shall be mutually agreed between Company and Vendor.




APPENDIX- 3 – WIND LOADING DATA As per Arthit General Specification AGS-18 (Site Conditions and Climate) the 100 year return Wind speed (3 second Gust) at 10m above LAT (Lowest Astronomical Tide) is 57m/sec. The corresponding wind speed at other elevations (Z) are estimated using the formula

VZ=V10(Z/10)0.12

Wind load is applied as uniform force along the pipe Wind force per unit length F = CfqD N/mm Where D = Outside diameter of the pipe, mm q = Dynamic pressure of the wind = ρV²/2 , N/m² Cf = Shape factor or Effective force co-efficient V = Wind Speed, m/sec ρ = Density of air = P/RT, Kg/m³ P = Atmospheric pressure = 101396.16 N/m² T = Average air temperature = 29°C as per Table 4.1 of AGS-18 R = Gas constant for air = 287.1387 N-m/Kg-°K Air Density at 29°C = 101396.16/[287.1387x(29+273)] = 1.1693 Kg/ m³ Wind Profile based on 100 year return interval, 3 second Gust Elevation m 5 10 15 20 25 30 35 40 45 50

Wind Speed m/sec 52.5 57.0 59.8 61.9 63.6 65.0 66.2 67.3 68.3 69.1

Wind Pressure N/m² 1611.4 1899.5 2090.7 2240.1 2364.9 2470.1 2562.2 2648.0 2727.3 2791.6

As per BS CP3, Chapter V, Part 2, values of shape factor Cf for pipe sections are as follows. Flow Regime

DV Value

Cf

Subcritical flow

DV < 6 m²/sec 6 ≤ DV < 12 m²/sec 12 ≤ DV < 33 m²/sec DV ≥ 33m²/sec

1.2 0.6 0.7 0.8

Supercritical flow

The above wind profile and shape factor values shall be used in CAESAR II Pipe Stress analysis. The ‘Y’ co-ordinate to be keyed-in for the starting node in CAESAR II input shall be the elevation in metres of the corresponding point in PDMS stress isometrics.




APPENDIX- 4 – TYPICAL RESTRAINT SYMBOLS USED IN STRESS ISOMETRICS

Hanger Support

Rest Support

Rest Support with Hold Down

Hanger Support with Pipe Guide

Rest Support with Pipe Guide

Rest support with Hold Down & Pipe Guide

Hanger Support with Pipe Axial Stop

Rest Support with Pipe Axial Stop

Rest Support with Hold Down & Pipe Axial Stop




APPENDIX- 4 (Contd.) TYPICAL RESTRAINT SYMBOLS USED IN STRESS ISOMETRICS

Pipe Guide & Axial Stop

Rest support with Pipe Guide Rest support with Hold Down & Axial Stop , Pipe Guide & Axial Stop

Spring Support (Pedestal type)

Spring Support with Pipe Guide

Spring Support With Axial Stop

Spring Support With Pipe Guide &Axial Stop

Spring hanger support, (Hanger type)

Spring hanger support with Pipe Guide

Spring hanger support with Axial Stop

Spring hanger support with Pipe Guide & Axial Stop

Kbr Piping Stress Specification

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