GIS 46-010 Specification for Pressure Vessels

8/10/2019 GIS 46-010 Specification for Pressure Vessels

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BP p.l.c.

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B01 Issued for Use Mike T Brown 10 Oct 2013 Michael Ho 10 Oct 2013 Mike T Brown 10 Oct 2013Rev Reason for Issue Author Date Checked Date Approved Date

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This document is copyright and shall notbe reproduced without the permission ofBP

Rev

GPO-EN-SPE-46010 B01

Specification for Pressure Vessels


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GPO-EN-SPE-46010 Page 2 of 2 Rev: B01

BP p.l.c. BP Internal

Group Instruction for Supply

GIS 46-010



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Page 2 of 96 GPO-EN-SPE-4601010 October 2013

Table of Contents

Page1 Scope .................................................................................................................................... 7

2 Normative references............................................................................................................. 7

3 Terms and definitions........................................................................................................... 10

4 Symbols and abbreviations .................................................................................................. 12

5 Order of precedence............................................................................................................ 14

6 Suppliers responsibilities..................................................................................................... 14

7 Design requirements............................................................................................................ 15

7.1 General..................................................................................................................... 157.2 Design loads and load combinations......................................................................... 16

7.3 Wind loading............................................................................................................. 16

7.4 Seismic loading......................................................................................................... 17

7.5 Snow loading ............................................................................................................ 17

7.6 Motion induced loads ................................................................................................ 17

7.7 Cyclic loading............................................................................................................ 17

7.8 Local loading............................................................................................................. 18

7.9 Wind-induced vibration of vertical vessels................................................................. 18

7.10 Transportation loads ................................................................................................. 19

7.11 Lifting loads............................................................................................................... 19

7.12 Design calculations................................................................................................... 20

7.13 Shock loading ........................................................................................................... 20

8 Materials requirements ........................................................................................................ 20

8.1 General..................................................................................................................... 20

8.2 Certificates of compliance ......................................................................................... 21

8.3 Certified material test reports .................................................................................... 21

9 Vessel components.............................................................................................................. 21

9.1 Vessel shells and transitions ..................................................................................... 21

9.2 Formed heads........................................................................................................... 21

9.3 Connections, nozzles, and manways ........................................................................ 22

9.4 Flanges..................................................................................................................... 25

9.5 Blind flanges and bolted flat heads ........................................................................... 27

9.6 Swing bolt closures................................................................................................... 27

9.7 Quick-actuating closures........................................................................................... 27

Copyright 2013 BP International Ltd. All rights reserved.

This document and any data or information generated from its use are classified, as a

minimum, BP Internal. Distribution is intended for BP authorised recipients only. The

information contained in this document is subject to the terms and conditions of the

agreement or contract under which this document was supplied to the recipient'sorganisation. None of the information contained in this document shall be disclosed

outside the recipient's own organisation, unless the terms of such agreement or contractexpressly allow, or unless disclosure is required by law.


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9.8 Supports ................................................................................................................... 27

9.9 Anchor bolts.............................................................................................................. 30

9.10 Internal attachments ................................................................................................. 31

9.11 External attachments ................................................................................................ 32

9.12 Removable internals ................................................................................................. 38

9.13 External jackets ........................................................................................................ 41

9.14 Nameplates............................................................................................................... 42

10 Spares ................................................................................................................................. 42

11 Fabrication requirements ..................................................................................................... 42

11.1 General..................................................................................................................... 42

11.2 Tolerances ................................................................................................................ 43

11.3 Joints ........................................................................................................................ 43

11.4 Welding..................................................................................................................... 44

11.5 Temporary welded attachments ................................................................................ 47

12 Examination requirements ................................................................................................... 47

12.1 General..................................................................................................................... 47

12.2 Preparation ............................................................................................................... 48

12.3 Examination of materials........................................................................................... 48

12.4 Surface examination of welds ................................................................................... 49

12.5 Volumetric examination of welds............................................................................... 49

12.6 Hardness testing....................................................................................................... 50

12.7 Repair of welding defects.......................................................................................... 50

12.8 Positive materials identification (PMI)........................................................................ 51

12.9 Production control test plates.................................................................................... 51

13 Inspection requirements....................................................................................................... 51

14 Post weld heat treatment ..................................................................................................... 51

15 Pressure test........................................................................................................................ 52

15.1 General..................................................................................................................... 52

15.2 Hydrostatic test ......................................................................................................... 53

15.3 Pneumatic test.......................................................................................................... 54

16 Cleaning, surface preparation, painting, and marking .......................................................... 54

16.1 Cleaning ................................................................................................................... 54

16.2 Surface preparation painting and non-metallic lining................................................. 55

16.3 Marking..................................................................................................................... 56

17 Preparation for shipment...................................................................................................... 57

17.1 General..................................................................................................................... 57

17.2 Preparations for the vessel ....................................................................................... 58

17.3 Preparations for spares and crated parts .................................................................. 58

17.4 Securing and padding............................................................................................... 59

17.5 Material safety data sheets ....................................................................................... 59

18 Documentation..................................................................................................................... 59

18.1 Proposal documentation ........................................................................................... 59

18.2 During design and fabrication ................................................................................... 60


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18.3 Final documentation.................................................................................................. 61

19 Quality management............................................................................................................ 63

20 Inspection, test and certification........................................................................................... 63

20.1 Inspection and test plan ............................................................................................ 63

20.2 Inspection access ..................................................................................................... 6320.3 Quality assurance ..................................................................................................... 63

21 Packing, preservation, marking and shipping....................................................................... 64

22 Supplier deliverables............................................................................................................ 64

Annex A (Normative) Supplementary requirements for special services ....................................... 65

A.1 General................................................................................................................................ 65

A.2 Anhydrous ammonia service................................................................................................ 65

A.3 Butane storage .................................................................................................................... 65

A.4 Amine service ...................................................................................................................... 65A.5 Caustic service .................................................................................................................... 65

A.6 Cyanides service ................................................................................................................. 65

A.7 Cyclic service....................................................................................................................... 66

A.8 Hydrofluoric acid .................................................................................................................. 66

A.9 Hydrogen service ................................................................................................................. 66

A.10 Cryogenic service ................................................................................................................ 67

A.11 Propane storage .................................................................................................................. 67

A.12 Sour water, wet H2S, or wet sour service ............................................................................. 67Annex B (Normative) Supplementary requirements for chrome-moly vessels ............................... 71

B.1 General................................................................................................................................ 71

B.2 Fabrication........................................................................................................................... 72

B.3 Examination requirements ................................................................................................... 72

B.4 1,25Cr-0,5Mo vessels (including Vanadium enhanced) ....................................................... 72

B.5 2.25Cr-1Mo vessels (including Vanadium enhanced) .......................................................... 72

Annex C (Normative) Supplementary requirements for stainless steel vessels ............................. 74

C.1 Fabrication........................................................................................................................... 74C.2 Welding................................................................................................................................ 74

C.3 Examination requirements ................................................................................................... 74

C.4 Cleaning and surface preparation ........................................................................................ 75

Annex D (Normative) Supplementary requirements for clad plate or weld-overlay construction .... 76

D.1 Design ................................................................................................................................. 76

D.2 Clad plate material............................................................................................................... 78

D.3 Cladding re-instatement....................................................................................................... 78

D.4 Weld overlay........................................................................................................................ 79D.5 Welding procedures............................................................................................................. 80


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D.6 Internal attachments ............................................................................................................ 81

D.7 Examination of weld overlay and clad re-instatement........................................................... 81

D.7.1 UT examination......................................................................................................... 81

D.7.2 PT examination......................................................................................................... 82

D.7.3 Chemical analysis ..................................................................................................... 82Annex E (Normative) Supplementary requirements for DHT and IPWHT ...................................... 83

E.1 Dehydrogenation heat treatment.......................................................................................... 83

E.2 Intermediate post weld heat treatment ................................................................................. 83

Annex F (Normative) Allowable piping loads on nozzles ............................................................... 85

Annex G (Normative) Ladders and platforms ................................................................................ 93

G.1. General................................................................................................................................ 93

G.2. Layout.................................................................................................................................. 93

G.3 Platforms ............................................................................................................................. 93G.4. Ladders, ladder cages, and safety gates.............................................................................. 96

G.5. Handrailing .......................................................................................................................... 96

List of Tables

Table 1 - Minimum transportation acceleration loadings................................................................ 19

Table 2 - Minimum thickness of nozzles........................................................................................ 23

Table 3 - Quality levels for straight beam examinations from flat surfaces .................................... 26

Table 4 - Skirt vents ...................................................................................................................... 29Table 5 - Dimensions of light lifting lugs........................................................................................ 35

Table 6 - Dimensions of heavy lifting lugs..................................................................................... 36

Table 7 - Tailing lug dimensions.................................................................................................... 37

Table 8 - Mist eliminator dimensions............................................................................................. 41

Table 9 - Flatness tolerances of gasket contact surface................................................................ 43

Table F.1 - Pipe size forces .......................................................................................................... 86

Table F.2 - De-rating factor ........................................................................................................... 86

Table F.3 - Allowable piping loads on nozzles............................................................................... 87Table G.1 - Minimum platform clearances..................................................................................... 95

List of Figures

Figure 1 - Skirts on vertical vessels less than 50 mm (2 in) thick or in non-cyclic service.............. 28

Figure 2 - Skirts on vessels 50 mm (2 in) thick or in cyclic service ............................................. 28

Figure 3 - Opening for skirt access or for piping............................................................................ 29

Figure 4 - Opening for a skirt vent................................................................................................. 29

Figure 5 - Design of light lifting lug ................................................................................................ 35Figure 6 - Design of heavy lifting lug ............................................................................................. 36


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Figure 7 - Design of tailing lug....................................................................................................... 37

Figure 8 - Mist eliminator used for the full diameter of a vessel..................................................... 38

Figure 9 - Mist eliminator for an enclosed internal cylinder............................................................ 39

Figure 10 - Mist eliminator for a reduced diameter ........................................................................ 39

Figure 11 - Mist eliminator attachment details ............................................................................... 40

Figure 12 - Mist eliminator support details..................................................................................... 41

Figure 13 - Surface Contours........................................................................................................ 56

Figure 14 - Internal attachments ................................................................................................... 56

Figure D.1 - Typical clad nozzle attachment to shell ..................................................................... 76

Figure D.2 - Attachment of lightly loaded attachment to a clad vessel........................................... 76

Figure D.3 - Attachment of a moderately loaded attachment to a clad vessel ............................... 77

Figure D.4 - Method for cladding a raised face flange ................................................................... 77

Figure D.5 - Method for cladding a ring type joint flange ............................................................... 77

Figure D.6 - Cladding re-instatement at a vessel seam................................................................. 79

Figure G.1 - Typical column platform and ladder elevations.......................................................... 94

Figure G.2 - Minimum clearances in platform design .................................................................... 95

Figure G.3 - Typical platform at the top of a vessel ....................................................................... 96


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1 Scope

a. This Specification provides requirements for the design, materials, fabrication, inspection,testing, documentation, and preparation for shipment of pressure vessels designed,

fabricated, and certified in conformance to one of the following standards:1. ASME Boiler and Pressure Vessel Code, Section VIII, Division 1.

2. ASME Boiler and Pressure Vessel Code, Section VIII, Division 2.

3. BSI PD 5500 Specification for Unfired Fusion Welded Pressure Vessels.

4. EN 13445 Unfired Pressure Vessels.

b. This specification also provides recommended design requirements for standard vesseldetails which may be used if desired by the vessel manufacturer or if specified to be usedon the engineering datasheet in the direct purchase of pressure vessels. The use of other

standard details, such as those provided by the engineering contractor or industryorganisations, is not precluded.

2 Normative references

The following documents are referenced in one or more requirements in this document. For datedreferences, only the version cited applies. For undated references, the latest version of the referenced

document (including any amendments) applies.

Company Documents

GIS 06-602 Specification for Coating and Painting of Supplier Equipment

GIS 18-012 Specification for Procurement, Storage, and Control of Welding

ConsumablesGIS 18-013 Specification for Weld Overlay, Integral Cladding, and Limited Loose

Lining of Pressure Vessels and Other Components

GIS 36-025 Requirements for Sour Service Materials for Upstream Oil and GasProduction Systems

GIS 36-102 Specification for Hardness Testing, Post Weld Heat Treatment, Stress

Relief, and Pickling for Pressure Vessels, Piping, and Other Components

GIS 36-103 Specification for Positive Materials Identification (PMI) for PressureVessels, Piping, and other Components

GIS 42-300 Specification for Flange Bolts

GIS 42-301 Specification for Gaskets

GIS 46-040 Specification for Internals for Columns

GP 36-26 Materials for Sour Service in Refining and Marketing Operations

American Petroleum Institute (API)

API Specification 5L Specification for Line Pipe.

API Specification Q1 Specification for Quality Programs for the Petroleum, Petrochemical andNatural Gas Industry

API RP 934-A Materials and Fabrication of 2 1/4Cr-1Mo, 2 1/4Cr-1Mo-1/4V, 3Cr-1Mo,and 3Cr-1Mo-1/4V Steel Heavy Wall Pressure Vessels forHigh-temperature, High-pressure Hydrogen Service


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API RP 934-C Materials and Fabrication of 1 1/4Cr-1/2Mo Steel Heavy Wall PressureVessels for High-pressure Hydrogen Service Operating at or below 825F(441 C)

API RP 934-E Closed Recommended Practice for Materials and Fabrication of 1 1/4CR-1/2 Mo Steel Pressure Vessels for Service above 825F (440C)

American Society of Mechanical Engineers (ASME)

ASME SA-263 Standard Specification for Stainless Chromium Steel-Clad Plate

ASME SA-264 Standard Specification for Stainless Chromium Nickel Steel Clad Plate

ASME SA-265 Standard Specification for Nickel and Nickel Base Alloy Clad Steel Plate

ASME SA-435/SA-435M Straight-Beam Ultrasonic Examination of Steel Plates

ASME SA-516/SA-516M Standard Specification for Pressure Vessel Plates, Carbon Steel, forModerate and Lower Temperature Service

ASME SA-541/SA-541M Quenched and Tempered Carbon and Alloy Steel Forgings forPressure Vessel Components.

ASME SA-578/SA-578M Standard Specification for Straight-Beam Ultrasonic Examination ofRolled Steel Plates for Special Applications

ASME SA-745/SA-745M Ultrasonic Examination of Austenitic Steel Forgings

ASME SA-770/SA-770M Through-Thickness Tension Testing of Steel Plates for SpecialApplications

ASME SA-841/SA-841M Steel Plates for Pressure Vessels, Produced by Thermo-MechanicalControl Process (TMCP)

ASME B16.5 Pipe Flanges and Flanged Fittings: NPS 1/2 through NPS 24 Metric/InchStandard

ASME B16.47 Large Diameter Steel Flanges: NPS 26 through NPS 60 Metric/InchStandard

ASME B31.3 Process Piping

ASME PCC-1 Guidelines for Pressure Boundary Bolted Flange Joint Assembly

ASME PCC-2 Repair of Pressure Equipment and Piping

ASME BPVC VIII-1 ASME Boiler and Pressure Vessel Code (BPVC), Section VIII, Division1: Rules for Construction of Pressure Vessels

ASME BPVC VIII-2 ASME Boiler and Pressure Vessel Code (BPVC), Section VIII, Division2: Alternative Rules

American Society for Testing and Materials (ASTM)

ASTM A380 Standard Practice for Cleaning, Descaling and Passivation of Stainless

Steel Parts, Equipment, and SystemsASTM A578 Standard Specification for Straight-Beam Ultrasonic Examination of

Rolled Steel Plates for Special Applications

ASTM E112 Standard Test Methods for Determining Average Grain Size

ASTM E165 Standard Practice for Liquid Penetrant Examination for General Industry

American Society of Civil Engineers (ASCE)

ASCE 7 Minimum Design Loads of Buildings and Other Structures

American Welding Society (AWS)

AWS A4.2 Standard Procedures for Calibrating Magnetic Instruments to Measure theDelta Ferrite Content of Austenitic and Duplex Austenitic-Ferritic

Stainless Steel Weld Metal


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AWS A2.4 Standard Symbols for Welding, Brazing, and Non-destructiveExamination

British Standards Institute (BSI)

BSI BS EN 1991-1-4 + A1 NA UK National Annex to Eurocode 1 - Actions on

structures Part 1-4: General actions - Wind actions - AMD 1BSI PD 5500 Specification for Unfired Fusion Welded Pressure Vessels

European Standards (EN)

EN 1991-1-4 + A1 Eurocode 1 - Actions on structures Part 1-4: General actions - Windactions

EN 10028-3 Flat products made of steels for pressure purposes Part 3: Weldable finegrain steels, Normalised

EN 10028-5 Flat products made of steels for pressure purposes Part 5: Weldable finegrain steels, Thermomechanically rolled

EN 10028-6 Flat products made of steels for pressure purposes. Weldable fine grain

steels, quenched and tempered

EN 10160 Ultrasonic testing of steel flat product of thickness equal or greater than 6mm (reflection method)

EN 10164 Steel products with improved deformation properties perpendicular to thesurface of the product. Technical delivery conditions

EN 10228-1 Non-destructive testing of steel forgings. Magnetic particle inspection

EN 10228-2 Non-destructive testing of steel forgings. Penetrant testing

EN 10228-3 Non-destructive testing of steel forgings. Ultrasonic testing of ferritic ormartensitic steel forgings

EN 10228-4 Non-destructive testing of steel forgings. Ultrasonic testing of austenitic

and austenitic-ferritic stainless steel forgingsEN 13445 Unfired pressure vessels

International Organisation for Standardisation (ISO)

ISO 8249 Welding - Determination of Ferrite Number (FN) in austenitic and duplexferritic-austenitic Cr-Ni stainless steel weld metals

ISO 8573-1 Compressed air - Part 1: Contaminants and purity classes

ISO 9001 Quality Management System - Requirements

ISO 15156-1 Petroleum and natural gas industries - Materials for use inH2S-containing environments in oil and gas production - Part 1: General

principles for selection of cracking-resistant materialsISO 15156-2 Petroleum and natural gas industries - Materials for use in

H2S-containing environments in oil and gas production - Part 2:

Cracking-resistant carbon and low-alloy steels and the use of cast irons

ISO 15156-3 Petroleum and natural gas industries - Materials for use inH2S-containing environments in oil and gas production - Part 3:

Cracking-resistant CRAs (corrosion-resistant alloys) and other alloys

National Association of Corrosion Engineers (NACE)

NACE MR0103 Materials Resistant to Sulfide Stress Cracking in Corrosive PetroleumRefining Environments

NACE MR0175 Petroleum, Petrochemical and Natural Gas Industries Materials for Usein H2S-containing Environments in Oil and Gas Production (ISO 15156)


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NACE SP0472 Methods and Controls to Prevent In-Service Environmental Cracking ofCarbon Steel Weldments in Corrosive Petroleum Refining Environments

NACE TM0284 Evaluation of Pipeline and Pressure Vessel Steels for Resistance toHydrogen-Induced Cracking

NACE TM0177 Laboratory Testing of Metals for Resistance to Sulfide Stress Cracking

and Stress Corrosion Cracking in H2S EnvironmentsSSPC SP 5/NACE No. 1 White Metal Blast Cleaning

Other References

Joseph Vellozzi, Ph.D Dynamic Response of Tall Flexible Structures to Wind Loading.,Department of Commerce, National Bureau of Standards, BuildingScience Series Number 32, 1966

Brownell and Young Process Equipment Design, Wiley & Sons Publishers, 1959

Zick, L.P Stresses in Large Horizontal Cylindrical Pressure Vessels on Two SaddleSupports, Pressure Vessels and Piping: Design and Analysis, A Decadeof Progress. Vol. 2, 1972

Process Industry Practices (PIP)

PIP STE05501 Fixed Ladders and Cages Design Guide

PIP STF05501 Fixed Ladders and Cages Fabrication Details

PIP STF05520 Details for Pipe Railing for Walking and Working Surfaces

PIP STF05521 Details for Angle Railings for Walking and Working Surfaces

PIP STF05530 Grating Fabrication Details

PIP STE05535 Vessel Circular Platform Detail Guidelines

PIP STF05535 Vessel Circular Platform Details

PIP VEFV1100 Vessel/S&T Heat Exchanger Standard Details (U.S. Customary Units)PIP VEFV1100M Vessel/S&T Heat Exchanger Standard Details (Metric Units)

Welding Research Council (WRC)

WRC Bulletin 297 Local Stresses in Cylindrical Shells Due to External Loadings on Nozzles

WRC Bulletin 368 Stresses in Intersecting Cylinders Subjected to Pressure

WRC Bulletin 537 Precision Equations and Enhanced Diagrams for Local Stresses InSpherical and Cylindrical Shells Due To External Loadings ForImplementation of WRC Bulletin 107

3 Terms and definitions

For the purpose of this Specification, the following terms and definitions apply:

ASME Code

ASME Boiler and Pressure Vessel Code.

Certificates of compliance

A document by which the material manufacturer (or seller to the extent that the Code allows) certifiesthat the material represented has been produced and tested in conformance to the requirements of thebasic material specification shown on the certificate.


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Certified material test report

A document, or documents, on which are recorded the results of tests, examinations, repairs, ortreatments required by the material specification.

Cladding re-instatement

The process in which areas at joints, nozzles and attachments, that have had cladding removed topermit welding of the base material, are re-clad by weld overlay.

Company

BP p.l.c., an associate or subsidiary, or other organisation acting as owner, purchaser, or customer asdesignated in the Purchase Order.

Company responsible engineer

Company engineer responsible for the technical requirements of the item.

Cyclic service

A service in which fatigue becomes significant due to the cyclic nature of mechanical and (or) thermalloads.

Fabrication plan

A detailed description of the processes and sequence of the processes to be used to fabricate thepressure vessel.

Ferritic steel

Steel where the predominant phase is ferrite, such as Carbon, Carbon Manganese, and low alloy steels.

Inspection and test plan

A detailed matrix of quality assurance and inspection activities to be performed. The format of thedocument includes provisions to indicate monitoring and witness points.

Manufacturer

An entity performing welding of a pressure vessel or pressure vessel parts. May or may not be theSupplier.

Quality assurance

Planned and systematic actions required to provide confidence that a product or service satisfies givenrequirements for quality.

Quality control plan

The manufacturers job specific documented plan for ensuring that all specified technical requirementsshall be followed.

Quality control system

The manufacturers documented system for ensuring that all applicable code requirements for themanufacturing process, including material handling and identification, design, fabrication, inspection

and testing, are followed.

Quality plan

A document setting out the specific quality practices, resources and sequence of activities for aparticular product, service or Purchase Order.


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Reinforcing plate

Reinforcing element as used in ASME Code, compensation plate as used in BSI PD 5500, orreinforcing plate as used in EN 13445.

Supplier

Entity entering into a Purchase Order with Company to provide materials, goods, supplies, equipment,or plant and includes the successors and (or) permitted assigns of such entity.

Weldment

Weld, HAZ, and adjacent parent metal.

4 Symbols and abbreviations

For the purpose of this Specification, the following symbols and abbreviations apply:

ASS Austenitic stainless steel.

CMCL Corrugated metal with covering layers.

CMTR Certified material test report.

DHT Dehydrogenation heat treatment.

DN Nominal pipe diameter.

FCAW Flux cored arc welding.

FEA Finite element analysis.

FN Ferrite number (per Welding Research Council Bulletin Number 342).

GMAW Gas metal arc welding.

GTAW Tungsten inert gas welding.

HAZ Heat affected zone.

HIC Hydrogen-induced cracking.

HRB Rockwell hardness number, B scale, tested with a steel ball.

HBW Brinell hardness measured by tungsten carbide ball (also referred to as HB andBHN).

Hv10 Vickers hardness measured with a 10 kgf indenter (also referred to as HV).

IPWHT Intermediate post-weld heat treatment (also known as ISR Intermediate stressrelief).

ITP Inspection and test plan.

LWN Long welding neck.

MAP Maximum allowable pressure.


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MAWP Maximum allowable working pressure.

MSDS Material safety data sheets.

MDMT Minimum design metal temperature.

MT Magnetic particle testing.

NDE Non-destructive examination.

NPS Nominal pipe size.

PCN Personnel Certification in Non-Destructive Testing.

PMI Positive material identification.

PQR Procedure qualification record.

PT Liquid or dye penetrant testing.

PWHT Post-weld heat treatment.

PWHTmin Shortest time for which the vessel may be heat treated to meet code requirements.

PWHTmax Longest time for which the vessel may be heat treated.

QA Quality assurance.

Q+T Quenched and tempered.

RT Radiographic testing.

RTV Room temperature vulcanising.

SAW Submerged arc welding.

SMAW Shielded metal arc welding.

SOHIC Stress orientated hydrogen induced cracking.

SZC Soft zone cracking.

TMCP Thermo-mechanical control process.

TOFD Time of flight diffraction.

UT Ultrasonic testing.

WFMT Wet fluorescent magnetic particle testing.

WPQ Welder or welding operator performance qualification.

WPS Welding procedure specification.


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5 Order of precedence

a. The order of precedence of the codes and standards quoted in the specifications shall be:

1. International and local statutory regulations.

2. Project data sheets.

3. Project specifications.

4. This Specification.

5. Referenced Company documents.

6. Referenced national and international codes.

b. Areas of apparent conflict between documents shall be brought to the attention ofCompany for resolution.

c. In the event of a conflict between this document and a relevant law or regulation, the

relevant law or regulation shall be followed. If the document creates a higher obligation, itshall be followed as long as this also achieves full compliance with the law or regulation.

d. Design, engineering, procurement, and construction for equipment shall comply with thestatutory laws and regulations of the final location of the asset. Refer to documents

identified in the Purchase Order for a list of these regulations.

e. For projects where the final location of the asset is in the EU:

1. Products supplied shall be confirmed to comply with applicable EU directives.

2. A Declaration of Conformity shall be provided.

3. The CE mark shall be affixed to the pressure vessel nameplate.

4. Components supplied shall be listed together with the EU directives with which they

comply and the rationale by which compliance has been achieved.5. A Technical File in compliance with applicable EU directives shall be compiled and

retained for a period of 10 years.

6 Suppliers responsibilities

a. The mechanical design, provision of materials, fabrication, inspection, testing, and qualityof workmanship of pressure vessels which shall be provided in conformance to thisSpecification and the following:

1. Comply with local jurisdictional requirements.

2. The required design code shall be as specified on the data sheets.3. Pressure equipment directive when specified on the data sheets.

4. Other codes and standards referenced in this Specification.

5. Additional requirements listed on the data sheets.

b. Vessels shall conform to the specified design code, including the application of code stampor certificate of conformity.

c. Vessels designed in conformance to the ASME Code shall be registered with the NationalBoard.

d. Design of a vessel or a vessel component furnished by Company shall not relieve the

Supplier of their responsibility to conform to the requirements of this Specification andother Purchase Order documents.


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e. Companys review and agreement of Supplier documentation shall not relieve the Supplierof their responsibility to conform to the requirements of this Specification and otherPurchase Order documents.

f. Company shall be allowed shop access for inspecting materials and activities during vesselfabrication for conformance to this Specification. Work or materials not conforming shall

be cause for rejection.g. Data sheets, drawings, quality control records, and other items which assist in determining

the acceptability of a vessel for inspection shall be made available to Company.

h. Release for shipment by Company inspector shall not relieve the Supplier of theirresponsibility to conform to the requirements of this Specification and Purchase Orderdocuments.

i. The Supplier shall be responsible for assuring that subcontracted fabrication work is inconformance to this Specification and Purchase Order documents, however no portion ofvessel construction, such as plate forming, welding, heat treatment, non-destructiveexamination, painting, shall be subcontracted without prior written agreement fromCompany.

7 Design requirements

7.1 General

a. Vessel design shall be in conformance to the applicable design code, this Specification,and all Purchase Order documents.

b. Computer calculations shall show input and output data, clearly state assumptions made,and specify program name and version number.

c. The maximum design temperature rating shall be increased to the highest temperature

permitted in conformance to the Code without affecting the minimum required thickness ofthe shell or heads and without changing the pressure class of the flanges.

d. A vessel may be designed and stamped for more than one condition of pressure andcoincident metal temperature.

e. Unless otherwise specified on the data sheets, vessels shall be assumed to operatecompletely filled with process fluid having a minimum specific gravity of 1,0.

f. MAWP shall be calculated based on actual construction unless otherwise specified on data

sheets.

g. For vessels constructed to ASME BPVC VIII-1, the coincident ratio used for calculatingthe MDMT of the vessel shall not be less than 1,0.

h. The supplementary requirements for special services shall conform to Annex A of thisSpecification if specified on data sheet.

i. Standard details provided by Supplier are not precluded, but details in this Specificationshall be used and fabricated as shown if specified on data sheets.

j. Document numbers PIP VEFV1100 and PIP VEFV1100M contain standard drawings,prefixed PIP VEFV in U.S. customary units and metric units respectively. ThisSpecification will reference metric standard drawing numbers only but it shall beinterpreted as also referring to the metric standard drawing (with suffix M) and equivalentstandard drawing in U.S. customary units (without suffix M).


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7.2 Design loads and load combinations

7.2.1 Design load classifications and definitions

The following definitions shall apply for the load case combinations specified in 7.2.2:

a. Dead load (L1) is the installed weight of the vessel, including internals, catalyst or

packing, refractory lining, platforms, insulation fireproofing, piping, and other permanentattachments. This does not include the weight of process liquid or catalyst contents.

b. Operating live load (L2) is the weight catalyst plus the weight of process liquid at thedesign liquid level, including that on trays.

c. Pressure load (L3) is the MAWP (internal or external at the coincident temperature)

considering the pressure variations through the vessel.

d. Thermal load (L4) is the load caused by the restraint of thermal expansion and interactionof vessel and its supports.

e. Test load (L5) is the weight of test water.

f. Wind load (L6) shall be determined in conformance to 7.3.

g. Seismic load (L7) shall be determined in conformance to 7.4.

h. Piping and superimposed equipment loads (L8) are loads caused by piping (based onAnnex F loadings), and loads caused by superimposed equipment. See 9.3.6.

7.2.2 Load conditions

Vessels and their supports shall satisfy all of the following load conditions:

a. Erected condition with full wind load (L1 + L6).

b. Design condition with wind load (L1 + L2 + L3 + L4 + L6 + L8).

1. Both full and zero pressure loads (L3) shall be included for check of maximumlongitudinal tensile and compressive stress.

c. Design condition with seismic load (L1 + L2 + L3 + L4 + L7 + L8).

1. Both full and zero pressure loads (L3) shall be included for check of maximumlongitudinal tensile and compressive stress.

d. Future (corroded) pressure test (L1+ test pressure + L5 + 0,25*L6).

1. Vessels shall be designed to permit application of a full hydraulic test in theiroperating positions and 25% design wind load.

2. The general primary membrane tensile stress under this load condition in the corroded

condition shall not be greater than either of the following:a) For hydrostatic testing, 90% of the specified minimum yield strength at 38C

(100F), in both circumferential and longitudinal directions.

b) For pneumatic testing, 80% of the specified minimum yield strength at 38C

(100F), in both circumferential and longitudinal directions.

e. Lift condition

1. See data sheets and 7.11.

2. Erection load shall be total erection weight of vessel multiplied by an impact factor asspecified in data sheet.

7.3 Wind loading

a. Unless otherwise specified on the data sheets:


18/97



1. For US sites, wind load shall conform to ASCE 7 and governing local jurisdictionalrequirements. The following shall be used in calculations:

a) Importance factor shall be Category III.

b) Velocity pressure exposure coefficient and gust response factors shall beExposure C for inland and coastal installations and Exposure D for offshore

installations.

2. For EU sites, wind loading shall conform to EN 1991-1-4 + A1.

3. For sites in the UK, wind loading shall conform to EN 1991-1-4 + A1, used inconjunction with BSI BS EN 1991-1-4 + A1 NA.

4. Wind load for other locations shall conform to data sheets and comply with localregulatory requirements.

b. Allowable deflection at any location on a vertical vessel in the corroded condition shall notexceed 150 mm per 30 m (6 in per 100 feet) of vessel height.

c. Projected area of vessel accessories such as platforms, ladders, piping, and other

equipment attached to the vessel shall be included in the wind load calculation.

d. Vessels fitted with spoilers:

1. Column projected area shall be calculated using the projected diameter taken at the

outside edge of the spoilers multiplied by the height of the section underconsideration.

2. Column projected area normal to wind and corresponding force coefficient, for thecolumn height shall be used in the design of vessel and supporting structure tocalculate the overturning load.

e. Wind induced moment and shear forces at the base of the vessel shall be specified onSupplier drawings.

7.4 Seismic loading

a. Unless otherwise specified on the data sheets, seismic loads shall be determined inconformance to ASCE 7 and governing local jurisdictional regulations.

b. Pressure vessel, supporting structures and foundation bolts shall be evaluated using theallowable stress design method.

c. Vertical columns shall be considered as cantilevered column systems if they areanchored to a foundation at grade.

d. Seismic induced moment and shear forces at the base of the vessel shall be specified on

Supplier drawings.

7.5 Snow loading

Unless otherwise specified on the data sheets, the snow load shall be determined inconformance to ASCE 7 and governing local jurisdictional regulations.

7.6 Motion induced loads

The motion induced loads listed on the data sheets shall be applied to all load cases listed in 7.2.

7.7 Cyclic loading

a. The rules in ASME BPVC VIII-2, Paragraph 4.1.1.4, shall be used as a basis for

establishing further action if a data sheet specifies a vessel is in cyclic service.


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b. A fatigue analysis shall be performed for agitator mounting nozzles and their attachment tothe vessel.

7.8 Local loading

a. Local stresses in vessel shell, heads and nozzles shall be evaluated using either

WRC Bulletin 297, 537 and 368 procedures, BSI PD 5500 annex G, or other local stressanalysis procedures agreed by Company based on:

1. The allowable imposed loads and moments on nozzles specified in Annex F of this

Specification.

2. The loads and moments imposed on attachments from piping and platforms.

b. For loads evaluated using WRC Bulletins 297, 537 and 368:

1. The allowable stresses for local nozzle loads and pressure at design temperature shallbe 1,5S for local primary membrane stress and 3S for primary membrane plussecondary bending stress at nozzles.

2. The allowable stresses for attachment local loads at ambient temperature shall be 1,0S

and 1,5S respectively.

c. S is the Code allowable or design stress.

d. For local loads evaluated in conformance to BSI PD 5500 annex G, the allowable stressesat ambient and design temperature shall conform to the code.

7.9 Wind-induced vibration of vertical vessels

a. Vessels with a height to diameter ratio of either the entire vessel or the top third of thevessel is greater than or equal of 15 shall be evaluated for dynamic behaviour from windexcitation as described in Dynamic Response of Tall Flexible Structures to Wind Loadingor by other similar proven evaluation methodology.

b. Critical wind velocities shall be determined for every change in vessel outer diameter.

c. Vessel critical wind velocities (first and second modes) shall be less than 7 m/s (15 mph)or greater than 27 m/s (60 mph).

d. For a vessel with critical wind velocities between 7 m/s (15 mph) and 27 m/s (60 mph):

1. A means of either preventing vortex formation (e.g., by spoilers, piping, ladders, orplatforms) or vibration dampening shall be provided.

2. Wind spoilers shall be added to the vessel in conformance to one of the followingmethods if it is established that a vessel may vibrate and the attachments of the vesselcannot be changed to put the vessel in a range where vibration cannot occur. The

method used to deter wind-induced vibration shall be agreed by Company.a) Helical spoilers

1) A three-start system of spoilers in a helical pattern shall be provided on topthird of the vessel.

2) Exposed width of the spoilers beyond insulation shall be 0,09D and a pitchof 0,5D, where D is the diameter of the top third of the vessel.

3) Spoiler system may be interrupted to provide clearance at vesselappendages.

b) Short vertical spoilers

1) A three-start system of short vertical spoilers arranged in a helical patternshall be provided on the top-third of the vessel.


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2) Exposed width beyond insulation of the spoilers shall be 0,09D and theheight of one helical wrap between 0,5D and 0,11D.

3) A minimum of eight spoilers shall be provided over the pitch distance (i.e.,each complete helical wrap) and a minimum of 1,5 helical wraps over thetop-third of the vessel.

4) Spoiler system may be interrupted to provide clearance at vesselappendages.

7.10 Transportation loads

a. Vessels subject to transportation loadings shall be analysed for the following conditions:

1. Bending between supports.

2. General primary membrane tensile stress.

3. Bending and compressive stress at supports and fixture attachment points.

b. Calculated general primary membrane tensile stress shall not exceed that listed in 7.11e.

c. Vessels shall be analysed for actual vertical, lateral, and longitudinal loadings.

d. Minimum acceleration loadings for different modes of transportation shall be as shown inTable 1.

e. Vessel shall be designed for the most severe vertical, lateral, and longitudinal loadingcondition if erection loadings are greater than the transportation loadings.

Table 1 - Minimum transportation acceleration loadings

Transportation Mode Vertical acceleration Lateralacceleration

LongitudinalaccelerationDownward Upward

Truck (highway speeds) 1,7g 0,5g 0,3g 1,8gTruck (


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1. Bending stresses in the vessel shell and skirt from the loadings imposed during the liftfrom horizontal to vertical position.

2. Calculated general primary membrane tensile stress shall not be greater than 80% ofthe materials specified minimum yield strength at 38C (100F).

3. Calculated compressive stress shall not be greater than 1,2 times the allowable

compressive stress.

7.12 Design calculations

a. Calculations satisfying the pressure vessel code of construction requirements shall beperformed using COMPRESS, PVElite, or Finglow software packages.

b. Design calculation reports, including finite element analysis reports, shall be submitted forreview and agreement by Company.

c. The following vessel components shall be subject to analysis and the results submitted forreview and agreement by Company:

1. Thermal and stress analysis of vessel and skirt attachment region, if specified on data

sheets.

2. Localised stress analysis of internal and external attachments to the shell.

3. Localised stress analysis of nozzles subject to piping loads.

4. Thermal analysis of nozzles, skirt, and appurtenances for thermal gradients inducedinto shell, if specified on data sheets.

a) Information from this analysis shall be used to determine the need for a fatigueevaluation.

b) Results of the thermal analysis exempting a vessel from fatigue evaluation shallbe included in the calculations.

d. For pressure vessels designed to ASME BPVC VIII-1, if a rule for the design of a vessel orvessel component subject to pressure does not exist in ASME BPVC VIII-1 then, inconformance to ASME BPVC VIII-1 Paragraph U-2(g), the design shall be evaluated byrules of ASME BPVC VIII-2.

e. Calculations evaluated to EN 13445-3 Annex B shall be submitted for review andagreement by Company.

7.13 Shock loading

Vessels shall be checked for dynamic effects if the data sheet indicates the possibility of theprocess applying a shock loading such as a slug flow which results in an increased force on the

vessel shell or internals.

8 Materials requirements

8.1 General

a. Pressure vessel materials shall be as specified on data sheets.

b. Materials shall conform to the following additional requirements in this Specification when

specified on data sheets:-

1. Annex B-supplementary requirements for chrome-moly vessels.

2. Annex C-supplementary requirements for stainless steel vessels.

3. Annex D-supplementary requirements for clad plate or weld overlay construction.


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c. Materials shall be new and unused.

d. Material substitutions shall not be made without Company agreement.

e. Steel plates shall be made in an open-hearth, basic-oxygen, or electric-arc furnace.

f. Charpy V-notch impact tests for carbon and low alloy steel plates shall conform to design

code unless specified otherwise in Purchase Order.g. Records of Charpy V-notch impact tests for steel plates shall record the percent shear

fracture and the lateral expansion for each specimen.

h. Impact test values shall be reported in the CMTR.

i. Materials shall be stamped with low stress (round bottom) stamps.

8.2 Certificates of compliance

a. Records of compliance with the requirements of material specifications shall bemaintained.

b. Certificates of compliance shall include reports or test results required by the materialspecification or Purchase Order.

8.3 Certified material test reports

a. Supplementary or special requirements, in addition to the requirements of the materialspecification, as required by the Purchase Order shall be included on the CMTR.

b. The specification of the material being represented, year of issue and material heat numbershall be included on the CMTR.

c. All such documents shall identify the applicable material specification and shall beidentified to the material represented.

9 Vessel components

The following clauses contain design, fabrication, and examination requirements for components ofpressure vessels as specified on the data sheets.

9.1 Vessel shells and transitions

a. Shells shall be fabricated from rolled plate, pipe or forgings.

b. Transitions shall be made with knuckle and flare if any of the following conditions apply:

1. Vessel is in cyclic or hydrogen service.

2. Section is subject to a major support reaction (for example, skirt-to-cone attachment).3. Transition thickness or attached shell thickness is over 30 mm (1,25 in).

4. All loadings per ASME BPVC VIII-1 Appendix 1-5 or 1-8, whichever is applicable,are not available.

c. Minimum thickness of shells and transitions shall not be less than 6 mm (1/4 in).plus thegreater of corrosion allowance and the forming allowance.

9.2 Formed heads

9.2.1 General

a. Heads shall be supplied as one of the following as specified on the data sheets:1. Hemispherical.


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2. 2:1 Semi-elliptical.

3. ASME flanged and dished.

4. Toriconical.

b. Dished head construction shall preferably be seamless.

c. Minimum thickness of heads shall not be less than 6 mm (1/4 in).plus the greater ofcorrosion allowance and the forming allowance.

d. Heads and head nozzles supporting agitators shall be reinforced to withstand the agitatordynamic loadings in conformance to requirements of 9.3.6a and 9.3.6b.

e. Head design shall be agreed with the agitator manufacturer and Company before the head

is ordered.

f. Carbon steel and C-Mn steels, cold-formed heads shall be normalised or stress-relievedprior to welding to the shell.

9.2.2 Joints in formed heads

a. Joints in formed heads shall be full penetration.

b. Joints in formed heads shall be fully radiographed before forming.

c. Joints in formed heads shall be ground flush with the plate surfaces before forming.

d. Spin hole which remains after forming and final construction shall be repaired with a metal

plate butt-welded in place and given full volumetric examination.

e. After forming, all joints in formed head shall receive 100% surface examination on bothsides.

9.2.3 Intermediate heads

a. Intermediate heads shall:

1. Be designed with a corrosion allowance applied to both sides.

2. Be fitted so that the internal head OD equals the shell ID.

3. Have a continuous fillet weld from the end of the head plate to shell.

4. Have the attachment welds magnetic particle or liquid penetrant examined.

9.3 Connections, nozzles, and manways

9.3.1 General

a. Connections shall not be made with:

1. Threaded coupling.

2. Socket weld fitting.

3. Single fillet welds.

4. Tapped or threaded openings.

b. Nozzles shall be flanged unless otherwise specified on the data sheets.

9.3.2 Design

a. MAWP shall not be limited by nozzle reinforcement or nozzle neck thickness.

b. MAP shall not be limited by nozzle reinforcement or nozzle neck thickness.


24/97



c. Nozzles with internal projections shall not include the internal projection in reinforcementcalculations.

d. Nozzles in dished heads shall be positioned such that the nozzle, reinforcing pads, andattachment welds are not within the knuckle region of the dished head.

9.3.3 Construction detailsa. Nozzles shall be set-in type.

b. Nozzle to parent component weld shall be full penetration.

c. Nozzles DN 300 (NPS 12) and larger shall be made from forgings, rolled plate, orseamless pipe.

d. Nozzles smaller than DN 300 (NPS 12) shall be constructed using forgings or seamlesspipe.

e. Nozzles DN 50 (NPS 2) or smaller shall be constructed using either:

1. LWN or heavier forgings if the forging length is 400 mm (16 in) or less.

2. Welding stub welded to seamless pipe if the nozzle length is greater than 400 mm

(16 in).

f. Flange rating of connections DN 50 (NPS 2) or smaller shall be minimum class 300.

g. Rolled plate used as nozzle necks shall have full volumetric examination prior toattachment to other components. Acceptance criteria shall be in conformance to the designcode for full NDE.

h. Minimum pipe schedule used for nozzles shall be as shown in Table 2 or applicable designcode, whichever is greater.

Table 2 - Minimum thickness of nozzles

Material Size DN (NPS) Minimum pipe schedule (1)

Carbon steel and low alloy,clad steels

50 (2) Schedule 160

Larger than 50 (2) Schedule XS

High alloy andnon-ferrous materials

50 (2) Schedule 80S

Larger than 50 (2) Schedule STD

Note:

1. Pipe wall thickness designations per ASME B36.10M.

i. Nozzles not directly connected to internals shall be flush with the inside surface of thevessel wall.

j. Nozzle with an internal projection shall have a fillet weld at the inside corner.

k. Inside edges of manways and nozzle neck shall be rounded to 3 mm (1/8 in) minimum

radius unless requirements in 16.2i.3 apply.

9.3.4 Reinforcing pads

a. Reinforcing pads shall be external to the vessel.

b. Reinforcing pads shall not be used on internal heads.

c. Reinforcing pads shall not be used if any of the following conditions apply:

1. Operating temperature exceeds 300C (572F).

2. Operating partial pressure of hydrogen exceeds 7 bar(a) (100 psia) and operatingtemperature exceeds 230C (450F).


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3. Design is for non-intrusive inspection.

4. Parent wall thickness exceeds 50 mm (2 in).

5. Ferritic vessels if operating temperature is lower than -50C (-58F).

6. Cyclic service.

d. Reinforcing pad thickness shall not exceed the parent wall thickness to which the nozzle isattached.

e. Reinforcing pads shall be full penetration welded to the nozzle.

f. Design of multi-segmental reinforcing pad elements shall conform to ASME BPVC VIII-1Paragraph UG-37(h).

g. Each pad segment shall have one American Standard Taper Pipe Thread (NPT) 1/4 inch(6 mm) telltale hole for testing purposes. Each hole shall be left open during welding ofpad and PWHT and located near the lowest point of a pad with the vessel in its operatingposition to permit drainage.

h. See 15.1f for testing of reinforcing pads.

i. Reinforcing pads that are not circular shall have rounded corners of 75 mm (3 in)minimum radius.

9.3.5 Nozzle external projection

a. Minimum projection from the outside of the vessel wall or external insulation to the nozzleface shall be:

1. Nozzles less than or equal to DN 200 (NPS 8): 200 mm (8 in).

2. Nozzles larger than DN 200 (NPS 8): 250 mm (10 in).

b. The dimension from the face of the nozzle to the vessel centreline or reference line shall be

rounded up to the next greater 10 mm (1/2 in) increment.

c. Projection of flanged nozzles with external piping attached shall permit removal of boltingfrom either side without removal of insulation.

d. Nozzles shall be extended to ensure flanges and bolting are outside vessel insulation.

e. Projections of nozzles and manways shall be established by applying the following:

1. Clearance shall be provided for removing flange stud bolts from between the flangeand vessel and for accessing flange stud nuts.

2. Clearance shall be provided for flange studs and nuts if nozzles penetrate insulation orplatforms.

9.3.6 Nozzle loading

a. Nozzles supporting agitators, pumps, or other mechanical equipment shall be evaluated towithstand the mechanical loadings specified by the equipment manufacturer and pipingloads derived from Table F.3 in Annex F. Nozzle reinforcement as determined by nozzlereinforcement calculations shall be used in the evaluation.

b. If, following evaluation, the vessel shell or head is overstressed, Supplier shall not increasereinforcement on nozzle but shall submit the calculations for review by Companyresponsible engineer.

c. Dynamic loading shall be evaluated for an infinite number of stress reversals using theapplicable stress concentration factor as follows:

1. 5 for as welded attachment welds.


26/97



2. 3,5 for contoured and blend ground nozzle attachment welds.

d. Nozzles supporting pressure relief devices shall be evaluated to withstand the thrust

reaction by using piping loads derived from Table F.3 in Annex F. Nozzle reinforcementas determined by nozzle reinforcement calculations shall be used in the evaluation andshall conform to requirements of 9.3.6b.

e. Gussets shall not be used to strengthen, stiffen, or reinforce nozzles, unless demonstratedby calculations to be designed for the specified cyclic life and thermal condition, and the

dimensional requirements, such as tolerances, of the device as furnished by the devicemanufacturer are considered.

9.4 Flanges

9.4.1 General

a. Flanges welded on a nozzle shall be weld neck type unless otherwise specified on datasheets.

b. Dimensions and pressure-temperature ratings of standard flanges for nozzles and manways

DN 600 (NPS 24) and smaller shall conform to ASME B16.5.

c. Dimensions and pressure-temperature ratings of standard flanges for nozzles and manwayslarger than DN 600 (NPS 24) shall conform to ASME B16.47 to the series specified on

data sheets.

d. Vessel shell flanges and head flanges with covers not conforming to sizes in ASME B16.5or ASME B16.47 shall be weld neck type and designed in conformance to the design code.

e. The following shall apply if studded nozzle pads are used:

1. Studded pad holes and studs shall be machined in conformance to drawing number

PIP VEFV1129M.

2. Indicator type studs for studded pads shall be in conformance to ASME PCC-1Figures 1 and 2.

3. Studded pads shall be checked to ensure the full thread depth holes conforms tospecified design code.

f. Bolt holes in all fixed flanges and studded pads shall straddle the natural centrelines.

g. For vessels supported on a skirt, the flanges of nozzles in bottom head shall be located

outside the skirt.

h. Except for standard flanges conforming to ASME B16.5 and B16.47, all carbon, low-alloy,and high-alloy steel forgings greater than 75 mm (3 in) thick shall be examined

ultrasonically in conformance to ASME SA-745/SA-745M and the following:

1. Quality levels for straight beam examinations from flat surfaces shall conform toTable 3.

2. Quality level for straight beam examinations from curved surfaces shall be QL-5.

3. Quality level for all angle beam examinations shall be QA-1. Notch depth shallconform to QA-1 or 6 mm (0,25 in), whichever is less.


27/97



Table 3 - Quality levels for straight beam examinations from flat surfaces

Forging thickness (t)mm (in)

Quality level

75 (3) < t 200 (8) QL-2

200 (8) < t 300 (12) QL-3t > 300 (12) QL-4

9.4.2 Flange facing and surface finish

a. Splice welds on gasket contact surfaces of a lap ring or flange shall not be used.

b. Flanges shall have one of the following configurations:

1. Raised face.

2. Ring type joint.

3. A construction that provides outer confinement to the gasket if specified on datasheets.

c. The height of a raised face shall be in conformance to ASME B16.5 or ASME B16.47unless otherwise specified on the data sheets.

d. Except for flanges conforming to ASME B16.5 and ASME B16.47, the gasket contactsurface flatness tolerance for flanges and shop-fabricated lap rings shall conform to thefollowing:

1. 0,150 mm (0,006 in) total indicator reading in both the radial and circumferentialdirections.

2. The total circumferential tolerance shall not occur in less than 20 degrees arc.

3. Measurement shall be made using a dial indicator after all other operations, including

fabrication and heat treatment of flange or lap ring, and attachment to the shell ornozzle neck, affecting flatness tolerance have been completed.

e. Flange facings shall be machined in conformance to ASME B16.5 and ASME B16.47.

f. Flange facings shall be protected from damage during fabrication, heat treatment, andshipping.

9.4.3 Flange bolting

a. Flanged joints shall be designed to enable the use of hydraulic bolt tensioners on thefollowing:

1. Joints with nominal bolt diameter 50 mm (2 in) and over.

2. Duties where the nominal bolt diameter is 40 mm (1,5 in) and over, and the flangesare either on hydrogen service or are PN 110 (Class 600) or over.

3. If specified on the data sheets for nominal bolt diameter 25 mm (1 in) and over.

b. Bolts for bolt tensioning shall be extended by the length of one nut and provided with a cap

for protection during service.

c. Nozzles adjacent to shell girth flanges or horizontal vessel saddles shall be located withclearance such that bolt tightening equipment can be used on the girth flange bolts.

d. Flange bolting, including coating requirements, shall be as specified on data sheets andconform to GIS 42-300.

9.4.4 Gaskets

a. Gaskets shall be as specified on data sheets and conform to GIS 42-301.


28/97



b. Pressure and leak test gaskets shall conform to 15.1j.

c. Spare gaskets shall conform to 10b.1.

9.5 Blind flanges and bolted flat heads

a. Except for blind flanges conforming to ASME B16.5 and B16.47, rolled plate for flat

covers and blind flanges greater than 75 mm (3 in) thick shall be examined in conformanceto ASME SA-578/SA-578M acceptance standard - Level B after cutting to final size.

b. Nozzles shall not be welded to blind flanges conforming to ASME B16.5 orASME B16.47 and weld neck reducing flanges shall be used unless the applicable ASMEblind flange standard specifically allows such an opening while keeping the pressure andtemperature rating.

c. Vessel manways and flanges fitted with blind flanges shall be supplied with bolting andgaskets.

9.6 Swing bolt closures

Swing bolts shall be of one-piece construction without welding. Hinge pins shall be solid and ofthe same material as the swing bolts.

9.7 Quick-actuating closures

a. Quick-actuating closures shall be designed per ASME BPVC VIII-1 Paragraph UG-35.2 orASME BPVC VIII-2 Paragraph 4.8 and Annex 4.B.

b. Procedures for the operation or maintenance of quick-actuating closure shall be submitted

for review and agreement by Company.

9.8 Supports

9.8.1 Skirts

a. Vertical vessels shall be self-supporting without guys or braces.

b. Unless otherwise specified on data sheets skirt supports shall conform to one of the

following standard drawings:

1. PIP VEFV1107M - Type A skirt base plate with gussets only

2. PIP VEFV1108M - Type B with cap plate and gussets

3. PIP VEFV1109M - Type C with cap plate and offset gussets

4. PIP VEFV1110M - Type D with top ring and gusset

c. A hot box shall be provided at the junction between the skirt and shell for vessels with adesign temperature of 345C (650F) and above.

d. Material at the top of the skirt for vertical vessels constructed from materials other thancarbon steel shall be the same material specification and grade as the vessel plate to whichit is attached for a length at least equal to the greater of the following:

1. 2,5 * (skirt radius * skirt thickness).

2. 600 mm (24 in).


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Figure 1 - Skirts on vertical vessels less than 50 mm (2 in) thick or in non-cyclic service

Figure 2 - Skirts on vessels 50 mm (2 in) thick or in cyclic service

Shell

Head / skirt

forging

Upper skirt section (same

material as vessel shell)

Forging Option Weld Buildup Option

Shell

Head

Weld buildup (with

ultrasonic examination)

Lower skirt section (Carbon steel)

e. Skirts on vessels 2 m (6 ft) diameter or less shall have at least one access opening. Vesselsover 2 m (6 ft) diameter and skirt heights over 2,5 m (8 ft), two access openings shall beprovided in the skirt.

f. Minimum skirt access opening shall be 600 mm (24 in) diameter or 450 mm x 900 mm

(18 in x 36 in) obround.

g. Openings for skirt access and piping shall conform to Figure 3. Additional strengtheningmay be provided by increasing the thickness of sleeve.

h. Unless specified otherwise on data sheets, a minimum of two 50 mm (2 in) radiussemi-circular drain holes 180 degrees apart shall be located at the vessel skirt to base ringattachment weld. The drain holes shall be staggered 90 degrees from the skirt vent holes.In applications where the inside of the skirt will be open or grated, the drain opening shallbe omitted.

i. Skirt openings for piping shall have a 13 mm (1/2 in) maximum clearance between thepipe outside diameter, including insulation, and skirt opening if inside of skirt is notfireproofed.

j. Openings for pipe vents shall conform to Figure 4.

k. Refer to Table 4 for quantities of skirt vents.


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Figure 3 - Opening for skirt access or for piping

6mm (1/4 in)

SLEEVE

MINIMUM SLEEVETHICKNESS OF tsk

76mm (3 in) MIN76mm (3 in) MIN

tsk BASE RING

6mm (1/4 in)

Where tskis skirt thickness

Figure 4 - Opening for a skirt vent

76mm (3 in) MIN

76mm (3 in) MIN

OD 114.3mm T8.8mm (NPS 4 SCH. 80)PIPE SLEEVE

6mm (1/4 in)

Table 4 - Skirt vents

Vessel Diameter at Skirt Attachment Number of

mm in Skirt Vents

< 900 < 36 2

> 900 to 1 500 > 36 to 60 4

> 1 500 to 2 400 > 60 to 96 6

> 2 400 to 4 500 > 96 to 180 8

> 4 500 > 180 12

9.8.2 Legs or column supports

a. Leg supports shall not bear on the knuckle or crown of formed heads but conform to one of

the following standard drawings unless otherwise specified on data sheets:

1. PIP VEFV1112M - Angle type leg without pad

2. PIP VEFV1113M - Angle type with reinforcing pad

b. Leg-type supports shall not be used on vessels greater than 1 524 mm (5 ft) diameter or6 100 mm (20 ft) tan. to tan.

c. Structural calculations shall be provided to verify adequacy of leg design.

d. Stress analysis of legs on spheres shall be submitted for review and agreement byCompany.


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9.8.3 Saddles

a. Unless otherwise specified on data sheets welded saddles shall conform to one of the

following standard drawings:

1. PIP VEFV1104M - Small horizontal vessel saddle supports

2. PIP VEFV1105M - Horizontal vessel saddles supported on concrete3. PIP VEFV1106M - Horizontal vessel saddles supported on structural steel

b. Horizontal vessels shall be investigated for buckling and local stresses. The method of L.P.Zick may be used for this investigation.

c. Horizontal vessels shall be supported on two saddles only.

d. Slots shall be provided for the anchor bolts in one saddle to allow for thermal expansion.

e. The saddle support that is fixed and the support that is sliding (slotted) shall beindicated on the fabrication drawings.

f. Saddles shall be continuously welded to the shell.

9.9 Anchor bolts

9.9.1 General

a. Calculations determining quantity and size of anchor bolts shall be based on referencedPIP standard details, and specified on fabrication drawings.

b. Supply of anchor bolts is not in Suppliers scope of supply.

c. Anchor bolts shall not be less than 19 mm (3/4 in) diameter.

d. Unless data sheets specify high-strength anchor bolts the following shall apply:

1. Anchor bolts (such as carbon steel, ASTM F1554-36, etc.) shall have an allowablestress of 138 MPa (20 000 psi) based on the tensile stress area of the threaded portion.

2. Maximum anchor bolt diameter shall be 76 mm (3 in).

e. Design loadings for anchor bolts embedded in concrete shall be determined by either thesimplified method (i.e., neutral axis of bolt pattern at centreline of vessel) or the shiftedneutral axis method in conformance toProcess Equipment Design.

f. Unless otherwise specified on data sheets, the design concrete bearing stress shall be11,4 MPa (1 658 psi) for vessels on concrete foundations.

9.9.2 High-strength anchor bolts

a. High strength anchor bolts may be used only if specified on the data sheets.

b. Unless otherwise specified on the data sheets, high-strength anchor bolts (such asASTM F1554-105) shall have an allowable stress of 207 MPa (50 000 psi).

9.9.3 Vertical vessel anchor bolts

a. Anchor bolts shall straddle normal centrelines.

b. Anchor bolt configuration shall provide radial clearance for a bolt tensioning device.

c. The number of anchor bolts shall be a multiple of four (4).

d. All parts of the base ring support system (base ring, chairs, compression ring, gussets,skirt, etc.) shall accommodate a pretension force on the anchor bolts equal to 75% of the

allowable anchor bolt stress.


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9.11 External attachments

9.11.1 General

a. External attachments welded to shells and heads shall be located to permit full visualinspection of attachment and attachment weld.

b. Ladders, platforms and clips shall conform to Annex G unless otherwise specified on datasheets.

c. Pipe segments shall not be directly attached to a pressure boundary and used as supportsfor ladders, platforms, piping, etc.

d. Welding of external attachments to the pressure boundary shall be continuous on all

surfaces to eliminate corrosion pockets.

e. All components welded directly to the pressure vessel envelope shall be fabricated fromthe same material as the vessel.

f. External attachments shall be designed and constructed to prevent the channelling and holdup of rainwater.

g. Minimum thickness of welded external attachments shall be 5 mm (3/16 in).

h. Minimum fillet weld size shall be 5 mm (3/16 in).

i. Seams and corner joints shall be sealed.

j. External attachments shall be designed and installed to satisfy one of the followingrequirements:

1. The distance between the weld-toe of the attachment is not within 50 mm (2 in) of apressure boundary weld toe.

2. The portion of the pressure boundary weld that is covered by the attachment shall beground flush and given 100% volumetric examination for the length of the overlapplus at least 50 mm (2 in) on each side before the attachment is made.

3. The attachment shall be coped or notched to clear all weld area and each weld-toe byat least 25 mm (1 in).

k. Stresses in the attachment and attachment weld shall be checked to ensure they are within

the allowable limits of the code of construction.

l. Galvanised clips or attachments shall not be welded to a vessel.

9.11.2 Insulation supports

a. Insulation supports shall comprise flat rings, rods, or lengths of angle attached to vertical

vessels in conformance to drawing number PIP VEFV1123M.pages 1, 2 and 5, unlessotherwise specified on data sheets.

b. Vertical vessel shell insulation shall be supported by one of the following methods:

1. Support rings which shall conform to the following details and locations shown indrawing number PIP VEFV1123M:

a) Type 2 or 3 intermediate ring supports in conformance to detail J.

b) Support rings for vessels with skirts located below the bottom tangent line inconformance to details E, G or H.

c) Ring spacing shall be between 3 000 mm (10 ft) and a maximum of 3 700 mm(12 ft) with the exception of upper support ring which shall be a maximum of

2 400 mm (8 ft) from top tangent line.


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c. Top heads of vessels insulation shall be supported by a floating ring and type 1 supportring fitted to the vessel in conformance to details A and J of drawing numberPIP VEFV1123M.

d. Insulation for bottom heads of vertical vessels shall be supported by one of the followingmethods:

1. A floating ring and anchor ring fitted to vessels with skirts in conformance to detailsE, G or H of drawing number PIP VEFV1123M.

2. A floating ring and type 1 support ring fitted to vessels without skirts in conformanceto detail J of drawing number PIP VEFV1123M.

e. Rings welded to vertical shell or skirt shall be discontinuous or perforated to prevent theaccumulation of moisture.

f. Insulation for heads on horizontal vessels shall be supported by a floating ring and anchorring fitted to the vessel in conformance to details on page 2 of drawing numberPIP VEFV1122M.

g. Horizontal vessels with shells 2 450 mm (96 in) diameter or larger shall have longitudinalsupports fitted in conformance to drawing number PIP VEFV1122M.

9.11.3 Fireproofing supports

a. Fireproofing supports shall be provided and installed on skirts and saddles if concretefireproofing is specified on the data sheets.

b. Fireproofing supports for concrete fireproofing shall conform to details in drawing numberPIP VEFV1123M.

9.11.4 Nameplate brackets

a. Unless otherwise specified on data sheets vessel nameplate brackets shall conform to

drawing number PIP VEFV1101M.

b. Nameplate brackets shall be located near a manway and shall not be obstructed if theman