NFPS Offshore Compression Complexes Project COMP2

COMPANY Contract No.: LTC/C/NFP/5128/20

CONTRACTOR Project No.: 033734

Document Title

:

FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

COMPANY Document No.

: 200-22-ST-SPC-00007

Saipem Document No.

: 033734-B-D-30-SPM-SD-S-10005

Discipline

: STRUCTURAL

Document Type

: SPECIFICATION

Document Category/Class

: 1

Document Classification

: Internal

00

A

18-Apr-2023

Cancelled

Ruddy Eko S

Danilo Manabat

01-Mar-2023

Issued for Review

Ruddy Eko S

Danilo Manabat

Huan Yew Jin / Chua Chan Hwa Huan Yew Jin / Chua Chan Hwa

REV.

DATE

DESCRIPTION OF REVISION

PREPARED BY

CHECKED BY

APPROVED BY

Saipem S.p.A.

Company No._Rev. 200-22-ST-SPC-00007_00

1 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

REVISION HISTORY

Revision

Date of Revision

Revision Description

A1

A

00

03-Feb-2023

Issued for Inter-Discipline Check

01-Mar-2023

18-Apr-2023

Issued for Review

Cancelled

HOLDS LIST

Hold No

Hold Description

1

Section 3.2 – Document Number of Project Documents

Company No._Rev. 200-22-ST-SPC-00007_00

2 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

TABLE OF CONTENTS

1

2

INTRODUCTION … 6

1.1 PROJECT OBJECTIVE … 6 1.2 PROJECT SCOPE … 6

DEFINITIONS AND ABBREVIATIONS … 8

2.1 DEFINITIONS … 8 2.2 TECHNICAL DEFINITIONS … 9 2.3 ABBREVIATIONS … 10

3

REFERENCE, RULES, CODES AND STANDARDS … 13

3.1 COMPANY DOCUMENTS … 13 3.2 PROJECT DOCUMENTS … 14 3.3 CONTRACTOR DOCUMENTS … 15 INTERNATIONAL CODES AND STANDARDS … 15 3.4

PURPOSE … 18

4.1 SYSTEM OF UNITS … 18 4.2 NON-COMPLIANCE / DEVIATIONS … 18

FABRICATION REQUIREMENT … 19

5.1 PERFORMANCE OF WORK … 19 5.2 NON-COMPLIANCE/DEVIATION … 19 5.3 DESIGN AND CONSTRUCTION … 19

4

5

5.3.1 General … 19

5.3.2 Materials … 19

5.3.3 Structural Pipe Fabrication … 20

5.3.4 Node Fabrication … 20

5.3.5 General Fabrication … 21

5.3.6 Assembly … 25

5.3.7 Workmanship … 30

5.3.8 Vortex Shedding … 30 5.4 CONTRACTOR ENGINEERING … 30 5.5 LIFT AND RIGGING REQUIREMENTS … 30 5.6 WEIGHT MEASUREMENT … 30 5.7 IDENTIFICATION AND MARKING… 30 5.8 CONSTRUCTION SITE FOUNDATION REQUIREMENTS … 31

5.8.1 General … 31

5.8.2 Site Investigation … 31

5.8.3 Foundation Design and Assessment … 32 5.9 DOCUMENTATION REQUIREMENTS … 32

6

QUALITY ASSURANCE PROVISION … 33

6.1

INSPECTIONS … 33

6.1.1 General … 33

6.1.2

Inspection Requirements … 33 6.2 TESTING … 34

Company No._Rev. 200-22-ST-SPC-00007_00

3 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

6.2.1 Testing of Jacket Members … 34

6.2.2 Pressure Testing of Grout Systems … 35

6.2.3 Pressure Testing of the Flooding System … 35

6.2.4 Test Fitting of Appurtenances … 36

6.2.5 Plated Surfaces and Drains … 36

7

WELDING … 37

7.1 WELDING – GENERAL … 37

7.1.1 Tack Welds … 38

7.1.2 Gaps and Buttering … 38

7.1.3 Seal Welding … 38

7.1.4 Fillet and Partial Joint Penetration (PJP) Welds … 38

7.1.5 Weld-Through Primers … 38

7.1.6 Backing Bars and Runoff Tabs … 38 7.2 APPROVED WELDING PROCESSES … 39 7.3 WELDING CONSUMABLES … 39

7.3.1 General … 39

7.3.2

Low-Hydrogen Welding Requirements … 40

7.3.3 Consumables Storage and Handling Procedure … 40

7.3.4 Fluxes and Submerged Arc Welding (SAW) … 40

7.3.5 Electrodes … 40

7.3.6 Wire Spools … 40

7.3.7 Consumable Identification … 41 7.4 FCAW REQUIREMENTS … 41 7.5 WELDING PROCEDURE QUALIFICATION … 42

7.5.1 General … 42

7.5.2 Weld-Through Primer Qualification Test … 44

7.5.3 Hardness Testing … 45

7.5.4 CVN Impact Testing … 46

7.5.5 CVN Impact Testing Acceptance Criteria… 46

7.5.6 Additional Essential Variable Requirements for Thickness Ranges … 47

7.5.7 Additional Essential Variables for CV2, CV2Z4, CV2Z5, CV2X, CV2ZX … 47

7.5.8 CTOD Requirements for CV2X and CV2ZX … 47 7.6 WELDING EQUIPMENT … 48

7.6.1 Condition of Equipment … 48

7.6.2 Grounding of Equipment … 48 7.7 PREHEAT AND INTERPASS TEMPERATURES … 49 7.8 WELDER AND WELDER OPERATOR QUALIFICATIONS … 49

7.8.1 Testing … 49

7.8.2 Previous Qualification… 49

7.8.3 Failure to Qualify … 49

Company No._Rev. 200-22-ST-SPC-00007_00

4 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

7.8.4 Additional Essential Variables … 50 7.9 WELD AND WELDER IDENTIFICATION AND MARKING … 50 7.10 WORKMANSHIP … 50

7.10.1 General … 50

7.10.2 Forming … 50

7.10.3 Preparation and Fit-Up … 51

7.10.4 Surface Considerations … 51

7.10.5 Distortions … 51

7.10.6 Cooling … 52

7.10.7 Weld Run-off Tabs and Access Holes … 52

7.10.8 Arc Strikes and Temporary Weldments … 52

7.10.9 Cleaning and Repairing of the Ends of Pipes, Plates, and Shapes … 52

7.10.10 Flame Straightening … 52 7.11 SAFETY … 53

8

9

CONTRACTOR REQUIREMENTS … 54

QUALITY ASSURANCE REQUIREMENTS … 55

9.1 QUALITY CONTROL … 55

10

NON-DESTRUCTIVE TESTING (NDT) … 57

10.1 GENERAL … 57 10.2 NDT PLAN … 57 10.3 PERSONNEL QUALIFICATIONS … 57 10.4 VISUAL INSPECTION (VT) … 58 10.5 RADIOGRAPHIC TESTING (RT) … 58 10.6 ULTRASONIC TESTING (UT)… 58 10.7 MAGNETIC PARTICLE TESTING (MT) … 59 10.8 PENETRANT TESTING (PT) … 59 10.9 CONTRACTOR INSPECTION RESPONSIBILITY … 59

11

WELDING REPAIRS … 61

11.1 GENERAL … 61 11.2 WELD REPAIR WPS QUALIFICATION … 62 11.3 TYPES OF WELD REPAIRS … 63

11.3.1 General … 63

11.3.2 Major Repairs … 63 11.4 GAPS AND BUTTERING … 64

12

13

MAJOR DELIVERABLES… 67

APPENDICES … 68

13.1 APPENDIX 1 INSPECTION REQUIREMENT AND NDT EXTENT FOR JACKET STRUCTURES … 69 13.2 APPENDIX 2 INSPECTION REQUIREMENT AND NDT EXTENT FOR DECK STRUCTURES … 71

Company No._Rev. 200-22-ST-SPC-00007_00

5 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

1

INTRODUCTION

The North Field is the world’s largest natural gas field and accounts for nearly all of the state of Qatar’s gas production. The reservoir pressure in the North Field has been declining due to continuous production since the early 1990s. The principal objective of the NFPS Project is to sustain the plateau from existing QG South Operation (RL Dry Gas, RGE Wet gas) and existing QG North Operation (QG1 & QG2) production areas by implementing an integrated and optimum investment program consisting of subsurface development, pressure drop reduction steps and compression. Refer to the figure below for a schematic of the North Field.

Qatargas Operating Company Limited is leading the development of the North Field Production Sustainability (NFPS) Project.

1.1 Project Objective

The objective of this Project includes:

• Achieve standards of global excellence in Safety, Health, Environment, Security and Quality

performance.

• Sustain the Qatargas North Field Production Plateau by installing new Compression Complex facilities CP6S & CP7S in QG south with integration to the existing facilities under Investment #3 program.

• Facility development shall be safe, high quality, reliable, maintainable, accessible, operable,

and efficient throughout their required life.

1.2 Project Scope

The Project Scope includes detailed engineering, procurement, construction, transportation & installation, hook-up and commissioning, tie-in to EXISTING PROPERTY and provide support for start- up activities of the following facilities and provisions for future development. The WORK shall be following the specified regulations, codes, specifications and standards, achieves the specified performance, and is safe and fit‐for‐purpose in all respects.

Offshore

CP6S and CP7S Compression Complexes that are part of QG-S RGE facilities as follows:

• CP6S Compression Complex

• Compression Platform CP6S, Living Quarters LQ6S, Flare FL6S

• Bridges BR6S-2, BR6S-3, BR6S-4, BR6S-5

• Bridge linked Tie-in to RP6S

Production from existing wellheads (WHP6S & WHP10S) and new wellhead (WHP14S) are routed via riser platform RP6S to compression platform CP6S to boost pressure and export to onshore via two export lines through the existing WHP6S pipeline and a new 38” carbon steel looping trunkline from RP6S (installed by EPCOL). CP6S is bridge-linked to RP6S.

• CP7S Compression Complex

• Compression Platform CP7S, Living Quarters LQ7S, Flare FL7S

• Bridges BR7S-2, BR7S-3, BR7S-4, BR7S-5

• Bridge linked Tie-in to RP7S

Company No._Rev. 200-22-ST-SPC-00007_00

6 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

CP7S shall receive production from existing wellheads (WHP5S & WHP7S) and new wellhead (WHP13S). There is only one export line for CP7S through the existing export pipeline from WHP7S. CP7S is bridge-linked to RP7S.

RGA Complex Destressing

Migration of the Electrical power source, Telecoms, Instrumentation and Control systems from WHPs and RHPs hosted by RGA to the respective Compression Complexes listed below:

• WHP6S, WHP10S, WHP14S, RP6S and RP10S to CP6S Compression Complex

• WHP5S, WHP7S, WHP13S and RP7S to CP7S Compression Complex

Destressing of Telecoms, Instrumentation and Control system in RGA Complex Control Room, which would include decommissioning and removal of telecom system devices and equipment that would no longer be required post migration and destressing activity.

Onshore

An Onshore Collaborative Center (OCC) will be built under EPC-9, which will enable onshore based engineering teams to conduct full engineering surveillance of all the offshore facilities. The OCC Building will be located in Ras Laffan Industrial City (RLIC) within the Qatar Gas South Plot. MICC & Telecommunication, ELICS related scope will be performed in the OCC building.

Figure 1.1: NFPS Compression Project COMP2 Scope

Company No._Rev. 200-22-ST-SPC-00007_00

7 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

2 DEFINITIONS AND ABBREVIATIONS

2.1 Definitions

Definition

Description

COMPANY

Qatargas Operating Company Limited.

CONTRACTOR

Saipem S.p.A.

DELIVERABLES

FACILITIES

All products (drawings, equipment, services) which must be submitted by CONTRACTOR to COMPANY at times specified in the contract. All machinery, apparatus, materials, articles, components, systems and items of all kinds to be designed, engineered, procured, manufactured, constructed, supplied, tested and permanently installed by CONTRACTOR at SITE in connection with the NFPS Project as further described in Exhibit 6.

fabricated,

MILESTONE

A reference event splitting a PROJECT activity for progress measurement purpose.

PROJECT

NFPS Offshore Compression Complexes Project COMP2

SITE

(i) any area where Engineering, Procurement, Fabrication of the the CPS6S and CP7S Compression FACILITIES related Complexes are being carried out and (ii) the area offshore required for installation of the FACILITIES in the State of Qatar.

to

SUBCONTRACT

Contract signed by SUBCONTRACTOR and CONTRACTOR for the performance of a certain portion of the WORK within the Project.

SUBCONTRACTOR

Any organization selected and awarded by CONTRACTOR to supply a certain Project materials or equipment or whom a part of the WORK has been Subcontracted.

WORK

Scope of Work defined in the CONTRACT.

WORK PACKAGE

The lowest manageable and convenient level in each WBS subdivision.

VENDOR

The person, group, or organization responsible for the design, manufacture, testing, and load-out/shipping of the Equipment/ Material.

Company No._Rev. 200-22-ST-SPC-00007_00

8 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

2.2 Technical Definitions

Definition

Description

Pcm

Carbon equivalent, based upon the chemical portion of the Ito- Bessyo carbon equivalent equation

Toughness Class CV1 Charpy testing at Lowest Anticipated Service Temperature (LAST)

Toughness Class CV2 Charpy testing below LAST

Toughness Class CV2X

Toughness Class CV2Z4

Charpy testing below LAST and API RP 2Z qualified

testing below LAST and API SR-4 Supplementary Charpy requirement for through-thickness testing per API SPEC 2W/API SPEC 2Y

Toughness Class CV2Z5

Charpy testing at 20oC below LAST and API SR-5 Supplementary requirement for low sulfur per API SPEC 2W/API SPEC 2Y

Toughness Class CV2ZX

Charpy testing below LAST, API RP 2Z qualified and API SR-4 Supplementary requirement for through-thickness testing per API SPEC 2W/API SPEC 2Y

Toughness Class NT

No Charpy testing required but materials shall be suitable for Yield Type toughness requirement at ambient temperature

Toughness Designator X

Indicates formal welding pre-qualification required

Toughness Designator Z4

Indicates through thickness properties required and verified by testing

Toughness Designator Z5

Toughness Designator ZX

Improved through thickness properties by limited sulfur content

Combination of Toughness Designators Z4 and X

Yield Type I

Specified Minimum Yield Strength (SMYS): 248 MPa (36 ksi)

Yield Type II

SMYS: 345 MPa (50 ksi)

Yield Type III

SMYS: 413 MPa (60 ksi),

Company No._Rev. 200-22-ST-SPC-00007_00

9 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

2.3 Abbreviations

Abbreviations

Definition

AFC

AISC

API

AWS

CE

CEQ

Approved for Construction

American Institute of Steel Construction

American Petroleum Institute

American Welding Society

Conformite Europeene

Carbon Equivalent

CGHAZ

Coarse Grain Heat Affected Zone

CJP

CL

CTOD

CVN

CWI

DFT

DN

DSAW

EPCI

ERW

FCAW

Complete Joint Penetration

Center Line

Crack Tip Opening Displacement

Charpy V-Notch

Certified Welding Inspector

Dry Film Thickness

Diameter Number (mm)

Double Submerged Arc Welded

Engineering Procurement Construction and Installation

Electric Resistance Welded

Flux Cored Arc Welding

FCAW-GS

Flux Core Arc Welding – Gas Shielded

FCAW-SS

Flux Core Arc Welding – Self Shielded

FEED

FL

GMAW

Front-End Engineering and Design

Fusion Line

Gas Metal Arc Welding

Company No._Rev. 200-22-ST-SPC-00007_00

10 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

Abbreviations

Definition

GMAW-S

Gas Metal Arc Welding – Short Circuiting Transfer

GTAW

Gas Tungsten Arc Welding

HAZ

HB

LAST

MDC

MT

MTR

NA

NDE

NDT

NFPS

NPS

PJP

PQR

PQT

PT

Heat-Affected Zone

Brinell Hardness

Lowest Anticipated Service Temperature

Material Description Code

Magnetic particle Testing

Material Test Reports

Not Applicable

Non-Destructive Examination

Non-Destructive Testing

North Field Production Sustainment

Nominal Pipe Size (inches)

Partial Joint Penetration

Procedure Qualification Report

Procedure Qualification Testing

Liquid Penetrant Testing

PWHT

Post Weld Heat Treatment

QAP

QG

RT

SAW

SI

SDR

Quality Assurance Program

Qatargas Operating Company Limited

Radiographic Testing

Submerged Arc Welded

Systeme Internationale

Specification Deviation Request

Company No._Rev. 200-22-ST-SPC-00007_00

11 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

Abbreviations

Definition

SMTS

SMYS

TMCP

TQ

TTP

UT

VT

pWPS

WPS

Specified Minimum Tensile Strength

Specified Minimum Yield Strength

Thermomechanical Controlled Process

Technical Query

Through-Thickness Properties

Ultrasonic Testing

Visual Testing

Preliminary Welding Procedure Specification

Welding Procedure Specification

Company No._Rev. 200-22-ST-SPC-00007_00

12 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

3 REFERENCE, RULES, CODES AND STANDARDS

The following codes, standards and specification are referenced within the document shall be considered as part of this specification. Conflict among applicable specification and / or codes shall be brought to the attention of the COMPANY for resolution COMPANY decision shall be final and shall be implemented. The latest editions of codes and specification effective as on date of contract shall be followed.

In general, the order of precedence shall be followed:

a) Qatari Governmental and Regulatory Requirements

b) COMPANY Procedures, Policies and Standards (Exhibit 5 Appendix I)

c) Project Specifications.

d) Industry Codes and Standards

e) COMPANY and CONTRACTOR’s Lessons Learned

If CONTRACTOR/SUBCONTRACTOR deems any deviations from the specifications will result in significant project cost and schedule saving, proposal to such deviations shall be submitted to COMPANY for review and approval. CONTRACTOR/SUBCONTRACTOR shall not proceed with any deviation to the specifications without prior COMPANY approval. In general, all design activities shall conform to legal and statutory regulations, and recognized industry best practices.

3.1 Company Documents

S. No

Document Number

Title

PRJ-PJL-PRC-004_07

Facilities Engineering and Vendor Document Numbering Procedure

PRJ-PJL-PRC-005_21

Facilities, System and Unit Number Codes and Descriptions Procedure

PRJ-PJL-PRC-006_01

Project Information Handover Procedure

PRJ-PJL-PRC-007_01

SmartPlant Engineering Applications & Drafting (CAD) Standard

PRJ-PJL-PRC-008_15

Equipment Numbering Philosophy

PRJ-PJL-PRC-048_11

PRJ-PJL-PRC-049_01

Facilities Documentation Metadata Requirements Procedure Project Acceptance Procedure

Information Handover, Verification

and

OMQ011 (181571_2_Part 2)

Updated Metocean Criteria Offshore Qatar, North Field, State of Qatar by Fugro, dated 19 Feb 2019, Rev.3

Company No._Rev. 200-22-ST-SPC-00007_00

13 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

3.2 Project Documents

S. No

Document Number

Title

LTC/C/NFP/5128/20

Contract Agreement

EXHIBIT 5

EXHIBIT 6

200-20-ST-SPC-00008

200-20-ST-SPC-00009

200-20-ST-SPC-00010

200-20-ST-SPC-00011

200-20-ST-SPC-00012

200-20-ST-SPC-00013

200-22-ST-SPC-00008

[HOLD]

[HOLD]

[HOLD]

[HOLD]

[HOLD]

[HOLD]

200-22-ST-DEC-00001

200-22-ST-DEC-00002

[HOLD]

[HOLD]

[HOLD]

Project Instructions

Scope of Work

Flooring

and Handrailing

Aluminum Helideck Specification for CP6S and CP7S Complexes Bridge Bearing Pad Specification for CP6S and CP7S Complexes Structural Material Specification for CP6S and CP7S Complexes Design of Deck Structures for Offshore Platforms Specification for CP6S and CP7S Complexes Structural Steel Pipe Supports Specification for CP6S and CP7S Complexes Open Grid Specification for CP6S and CP7S Complexes Structural Steelwork Hot Dip Galvanizing Specification Skid Mounted Assemblies – Structural Requirement for CP6S and CP7S Complexes Structural Fatigue Life Improvement by Weld Grinding Specification for CP6S and CP7S Complexes Specification for Design of Jacket and Piles for CP6S and CP7S Complexes Painting Specification for CP6S and CP7S Complexes Jackets Painting Specification for CP6S and CP7S Complexes Topsides Cathodic Protection Specification for CP6S and CP7S Complexes Greenfield Topsides Structural Design Basis for CP6S and CP7S Complexes Greenfield Topsides Structural Design Brief for CP6S and CP7S Complexes Jacket – Structural Design Basis for CP6S and CP7S Complexes Jacket – Structural Design Brief for CP6S and CP7S Complexes Brownfield Structural Design Basis Brownfield Offshore

for

Company No._Rev. 200-22-ST-SPC-00007_00

14 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

S. No

Document Number

Title

[HOLD]

200-20-ST-PRC-00002

200-20-ST-PRC-00003

Brownfield Structural Design Brief for Brownfield Offshore Weight Control Procedure for Greenfield for CP6S and CP7S Complexes Weight Control Procedure for Vendor for CP6S and CP7S Complexes

3.3 Contractor Documents

S. No

Document Number

Title

Not Applicable

Not Applicable

3.4

International Codes and Standards

S. No

Document Number

Title

AISC-ASD

API RP 2A-WSD

API RP 2Z

API SPEC 2B

API SPEC 2H

API SPEC 2MT1

API SPEC 2W

API SPEC 2Y

Manual of Steel Construction, Allowable Stress Design, 9th Edition 1989, issued by American Institute of Steel Construction Recommended Practice for Planning, Designing and Constructing Fixed Offshore Platforms - Working Stress Design, 22nd Edition Recommended Practice for Preproduction Qualification for Steel Plates for Offshore Structures, 4th Edition Specification for the Fabrication of Structural Steel Pipe, 6th Edition Specification for Carbon Manganese Steel Plate for Offshore Structures, 9th Edition Specification for Carbon Manganese Steel Plate with Improved Toughness for Offshore Structures, 2nd Edition Specification for Steel Plates for Offshore Structures, Produced by Thermo-Mechanical Control Processing (TMCP), 6th Edition Specification for Steel Plates, Quenched-and- Tempered, for Offshore Structures, 5th Edition

API SPEC 5L

Specification for Line Pipe, 46th Edition

API RP 2X

Recommended Practice for Ultrasonic and Magnetic Examination of Offshore Structural Fabrication and

Company No._Rev. 200-22-ST-SPC-00007_00

15 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

S. No

Document Number

Title

ASME SEC V

BPVC Section V - Non destructive Examination, 2019

Guidelines for Qualification of Technicians, 4th Edition 2004

ASNT SNT-TC-1A

ASTM A123/A123M

ASTM A36/A36M

ASTM A572/A572M

ASTM A578/A578M

ASTM A6/A6M

ASTM E165

ASTM E384

Recommended Practice, Personnel Qualification and Certification in Non-destructive Testing, 2020 Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Product, 2017 Standard Specification for Carbon Structural Steel, 2019 Standard Specification for Carbon Structural Steel, 2019 Standard Specification for Straight-Beam Ultrasonic Examination of Rolled Steel Plates for Special Applications, 2017 Standard Specification for General Requirements for Rolled Structural Steel Bars, Plates, Shapes and Sheet Piling, 2022 Standard Practice for Liquid Penetrant Examination for General Industry, 2018 Standard Test Method for Knoop and Vickers Hardness of Materials, 2017

ASTM E709

Standard Guide for Magnetic Particle Testing, 2015

ASTM E1290

AWS A4.3

AWS A5.01/A5.01M

AWS A5.1/A5.1M

AWS A5.4/A5.4M

AWS A5.17/A5.17M

AWS A5.18/A5.18M

AWS A5.20/A5.20M

AWS A5.23/A5.23M

AWS A5.29/A5.29M

Standard Test Method for Crack-Tip Opening Displacement (CTOD) Fracture Toughness Measurement, 2008 Standard Methods for Determination of the Diffusible Hydrogen Content of Martensitic, Bainitic, and Ferritic Steel Weld Metal Produced by Arc Welding, 1997 Procurement Guidelines for Consumables - Welding and Allied Processes - Flux and Gas Shielded Electrical Welding Processes, 2019 Specification for Carbon Steel Electrodes for Shielded Metal Arc Welding, 14th Edition Specification for Stainless Steel Electrodes for Shielded Metal Arc Welding, 11th Edition Specification for Carbon Steel Electrodes and Fluxes for Submerged Arc Welding, 7th Edition Specification for Carbon Steel Electrodes and Rods for Gas Shielded Arc Welding, 8th Edition Specification for Carbon Steel Electrodes for Flux Cored Arc Welding, 2005 Specification for Low-Alloy and High Manganese Steel Electrodes and Fluxes for Submerged Arc Welding, 6th Edition Specification for Low-Alloy Steel Electrodes for Flux Cored Arc Welding, 2010

Company No._Rev. 200-22-ST-SPC-00007_00

16 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

S. No

Document Number

Title

AWS D1.1/D1.1M

Structural Welding Code – Steel, 2020

AWS D1.8/D1.8M

Structural Welding Code - Seismic Supplement, 2016

BSI BS EN ISO 15653

BSI BS EN ISO 8571

Metallic Materials - Method of Test for the Determination of Quasistatic Fracture Toughness of Welds, 2018 Method of test for determination of fracture toughness in metallic materials using single edge notched tension (SENT) specimens, 2018

BS EN 10025

Hot Rolled Products of Structural Steels, 2004

BS EN 10225

EEMUA 158

ISO 3690

ISO 4063

Weldable Structural Steels for Fixed Offshore Structures, 2019 Construction Specification for Fixed Offshore Structures, Publication 158, Edition 3, 2014 Welding and Allied Processes - Determination of Hydrogen Content in Ferritic Steel Arc Weld Metal, 2018 Welding and Allied Processes - Nomenclature of Processes and Reference Numbers, 2009

ISO 9001

Quality Management Systems – Requirements, 2015

ISO 9712

Non-destructive testing - Qualification and certification of NDT personnel - Fifth edition

NORSOK M-101

Structural Steel Fabrication, Edition 5, 2011

Company No._Rev. 200-22-ST-SPC-00007_00

17 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

4 PURPOSE

The purpose of this document is to define the technical requirements for fabrication, welding and inspection of structural material for use in the fabrication of offshore structures of the North Field Production Sustainability (NFPS) Compression Complexes Project (COMP2).

It covers structural welding and inspection including materials, equipment, workmanship, testing and other items required to weld and inspect offshore structures. This specification is not applicable to skids structure, it will be reported in separate document “Skid Mounted Assemblies - Structural Requirement Specification for CP6S and CP7S Complexes”, Ref. [19].

4.1 System of Units

The System International (SI) units are adopted for the analyses and calculations unless otherwise noted.

4.2 Non-Compliance / Deviations

If any requirements of this specification cannot be met, VENDOR/SUPPLIER must provide written notification of non-compliances, with explanations, in accordance with the project instructions and Project Specification Deviation and CONTRACTOR Concession Request. This notification will be evaluated and must have COMPANY approval before final acceptance.

Company No._Rev. 200-22-ST-SPC-00007_00

18 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

5 FABRICATION REQUIREMENT

5.1 Performance of Work

All references listed in Section 6 of this Specification shall be complied with. All works shall be performed in accordance with the Approved for Construction (AFC) Drawings

5.2 Non-Compliance/Deviation

If any requirements of this specification cannot be met, VENDOR/SUPPLIER must provide written notification of non-compliances, in accordance with Project Procedure: SPECIFICATION DEVIATION AND CONTRACTOR CONCESSION REQUEST PROCEDURE.

5.3 Design and Construction

5.3.1 General

1. Painting shall be in accordance with Painting Specification for CP6S and CP7S Complexes Jackets,

Ref. [22] and Painting Specification for CP6S and CP7S Complexes Jackets, Ref. [23].

2. Welding and inspection of structural fabrication shall be in accordance with this project specification.

3. Design wind speed for construction yard engineering shall be the maximum of a) the local 10-year return period wind speed or b) the design wind speed required by local regulations. A lower design wind speed may be used for activities that are restricted to occur inside a defined weather window. Vortex shedding shall be checked per Specification for Design of Jacket and Piles for CP6S and CP7S Complexes, Ref. [21] and Design of Deck Structures for Offshore Platforms Specification for CP6S and CP7S Complexes, Ref. [15].

4. Where COMPANY approval is required, CONTRACTOR shall obtain this approval in writing.

5.3.2 Materials

1. All materials shall be in accordance with Structural Material Specification for CP6S and CP7S

Complexes, Ref. [14].

2. CONTRACTOR may submit a material type substitution request in writing to COMPANY Representative for approval, allowing reasonable time for evaluation without disruption of the construction schedule. Substitutions that have not been approved in writing by COMPANY will not be accepted and shall be removed from the work and replaced by CONTRACTOR with the specified materials. The request shall include the following:

a) The nature and extent of the substitution

b) Effect on the cost and schedule

c) Full specification and chemical and mechanical properties

d) Material Test Reports of the proposed substitute

e) A complete list of technical differences between the project material and the proposed substitution

f) Any other pertinent information requested by COMPANY

3. Steel shapes, plate, and pipe for fabrication shall be new and free from damage, rust, and mill scale. If laminations or split ends exist in plate, pipe, or rolled shape, the extent of the defect shall be determined and repaired in accordance with the appropriate material delivery specification or replaced if out of specification or if repair per specification is not possible.

Company No._Rev. 200-22-ST-SPC-00007_00

19 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

5.3.3 Structural Pipe Fabrication

1. Structural steel pipe shall be fabricated in accordance with API Spec 2B, Ref. [37] and this project specification. This shall also be valid for assembling the sub-assemblies as supplied by VENDOR.

2. The preferred method of edge preparation prior to forming is by press break with preformed blades. If progressive crimping by the wedge technique is employed, the wedge shall exhibit a radius of curvature approximately equal to that of the final member size and shall be designed to avoid indentation marks on the plate surface. “Rippling” of the finished member surface between wedge locations is cause for rejection. Shearing shall be limited to carbon steels of 10 mm (3/8 in.) thickness.

3. For tubulars with diameter-to-thickness ratio of less than 20:1, Hot or Cold Forming with COMPANY-

approved procedures shall be used.

4. Longitudinal and circumferential weld seams shall be clearly shown on the shop drawings.

5. Splices in pipe greater than 812 mm (32 in.) diameter with 19 mm (3/4 in.) or greater wall thickness shall be full penetration double-vee butt joints once accessible, welded from both sides. Single-vee butt joints can be applied if satisfy the design requirement and subject to COMPANY approval.

6. Splices in sections of pipe less than 812 mm (32 in.) in diameter shall be full penetrations, single- vee butt joints, welded from one side only. Backing strips or bars are not allowed without prior case- by-case COMPANY approval. Backing strips shall not be used on pump casings, risers, or any pipe carrying gas or liquid.

7. Maximum weld reinforcement at splices shall be 21/2 mm (3/32 in.) for members having a thickness

of 12 mm (1/2 in.) or less and 3 mm (1/8 in.) for thicknesses over 12 mm (1/2 in.).

5.3.4 Node Fabrication

Joint details shall be in accordance to API RP 2A-WSD, Ref. [35] and EEMUA Publication 158, Ref. [70], with the exceptions listed below:

1. The orientation of node cans in deck legs and braces shall be such that the longitudinal weld seam does not intersect with welds to other bracings at the joint. In the case of X-joints (intersection of two continuous braces) of approximately the same diameter, the orientation of the longitudinal seam on the through-brace member shall be approximately midpoint between the crown and the saddle of either of the incoming braces. The longitudinal seam for other types of node cans shall be oriented to avoid incoming braces when possible. When unavoidable, the longitudinal seam may be within the brace footprint but not at the centerline (within the middle one-third) and not near the edge (outer one-sixth) of incoming braces.

2. An exception for detailing of tubular joints is that the tapers of chord-cans shall be placed outside

the minimum can length specified by API RP 2A-WSD, Ref. [35].

3. Circumferential (girth) weld seams shall not be permitted to intersect welds to incoming braces on any type of node can without prior written approval by COMPANY. Where there is no reasonable alternative, approval will be granted to locate girth seams at or near the centerline (within the middle one-third) of incoming braces.

4. A minimum 75 mm (3 in.) overlap shall be supplied between adjacent braces when overlapping is required to keep brace centerline offset dimension(s) less than D/4, where D is Diameter. The overlap shall be measured radially from the intersection of the overlapping braces to the surface of the chord member.

5. Backing strips shall not be used at tubular or box seam nodes without prior COMPANY approval.

Company No._Rev. 200-22-ST-SPC-00007_00

20 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

5.3.5 General Fabrication

5.3.5.1 General

1. All structures and equipment shall be grounded (earthed) immediately upon installation. Fuel shall be stored on the Work Site (including temporary facilities sites) only at locations and in containers approved by COMPANY. Fueling of construction equipment shall not be done within 30.5 m (100 ft) of hot work.

2. CONTRACTOR shall prepare shop drawings for all fabrication work of critical and main structural member/Joint and shall submit these for review and endorsement by COMPANY Representative prior to beginning fabrication.

5.3.5.2 Slotted Members

Where slotted members are required, they shall be slotted to receive gusset plates in accordance with API RP 2A-WSD, Ref. [35] and the following:

1. The longitudinal seam shall be at least 90 degrees from the slot when members are to be slotted unless more than 2 slots are necessary, in which case a 45-degree separation shall be maintained.

2. Deviation to these requirements will require COMPANY approval.

3. Where members are slotted, all re-entrant corners in the slotted member shall have a minimum

radius of T/2, where T is the thickness of the material inserted in the slot.

5.3.5.3 Seal Welds and “Boxing In”

1. Any surface above mean water level and inaccessible to obtain a suitable coating but subject to corrosion shall be sealed by a filet weld or by “boxing in” with steel plate. All members that require coating and intersect at an angle of less than 20 degrees shall be boxed in.

2. All contacting steel surfaces shall be seal welded to prevent corrosion between the contacting

surfaces.

3. When seal welding is not achievable or practicable, then boxing plates shall be used to completely

seal off inaccessible surfaces from the outside atmosphere.

5.3.5.4 Stiffeners and Pad Eyes

1. Stiffeners shall be at least 150 mm (6 in.) from longitudinal seams.

2. Stiffeners and padeye plates shall be fitted accurately, neatly, and tightly as specified in this Project Specification. The padeye hole shall not be flame cut and shall have a uniform smooth milled finish.

3. All material for fabrication of padeyes shall be 100 percent ultrasonically tested for laminations in

accordance with ASTM A578/A578M, Ref. [49] to acceptance standard level A.

4. Pad eye plates are to be oriented so that the lifting loads will be applied parallel to the rolling direction

of the plate.

5. Fabrication and assembly procedures shall be selected to permit the final angle or orientation of the

pad eyes to be established as late in the fabrication process as is reasonably possible.

6. Pad eyes and lift trunnions shall be placed no closer than 90 degrees from longitudinal seam welds

of steel tubulars.

7. Unless otherwise shown on the Contract drawings, padeyes shall have the lifting shackle holes drilled within a 3 mm (1/8 in.) tolerance of the nominal pin diameter. Holes for pad eyes with cheek plates shall be drilled after cheek plates are completely welded in place.

Company No._Rev. 200-22-ST-SPC-00007_00

21 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

8. A gas release hole shall be drilled into the cheek plate prior to welding.

5.3.5.5 Bolted Connections

1. All bolts shall conform to Structural Material Specification for CP6S and CP7S Complexes, Ref. [14].

2. The bolting surfaces shall be smooth and without burrs.

3. Bolts shall be placed into the holes without damaging the threads.

4. Bolts in bearing shall be threaded to such a length that no more than one thread will be within the grip of the structural members. The bolts shall be of a length that will extend entirely through, but no more than 12 mm (1/2 in.) beyond the nuts.

5. High strength bolts shall be installed in accordance with AISC-ASD, Ref. [34] or as specified by the

Bolt Manufacturer.

6. Electrical isolation of bolted connections of dissimilar materials shall be per Approved for

Construction (AFC) drawings endorsed by COMPANY.

5.3.5.6 Beam Splices

Segments of beams with the same cross-sections may be spliced. The use of the beam shall determine the location and frequency of splicing. Splices shall be in accordance with API RP 2A-WSD, Ref. [35] and AWS D1.1/D1.1M, Ref. [64]. For primary and secondary structural steel, splices shall meet the following location requirements:

1. Splices in cantilever beam shall not be located in the 1/2-length near the support.

2. Splices in beam with supports at both ends shall not be located in the 1/8-length near each support

or 1/4-length in the middle section.

3. Flange splices in plate girders shall be at least 150 mm (6 in.) from web splices. Flange web splices

in all beams and plate girders shall be at least 150 mm (6 in.) from any stiffeners.

4. Lapped joints are not permitted.

5. Flange splices shall be 305 mm (12 in.) from incoming braces or other girders.

6. Backing strips shall not be used at box beam splices without prior COMPANY approval.

5.3.5.7 Miscellaneous Splices

1. Splices in ring stiffeners shall be located at 120-degree intervals.

2. Ring stiffeners shall not be located within 150 mm (6 in.) of the circumferential seams in joint cans, except at conical transitions, where they shall be at least 50 mm (2 in.) from the transition girth weld.

3. Ring stiffener web and flange splices shall be at least 100 mm (4 in.) apart.

4. All timber splices shall be staggered a minimum of 1.5 m (5 ft).

5.3.5.8 Deck Plate

1. Single-pass continuous seal welds with minimal or no preheat, located between the deck plate and

the deck beams or girders, shall be limited to a maximum of 5 mm (3/16 in.) fillet weld.

2. The use of a low heat input welding process is encouraged to minimize distortion. The Gas Metal-

Arc Welding-Short Arc (GMAW) process is encouraged for the welding of deck plate.

3. All welds between plate sections shall be made directly over structural members or shall be double- bevel full penetration welds. When this requirement cannot be met, COMPANY approval shall be

Company No._Rev. 200-22-ST-SPC-00007_00

22 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

obtained and a 50 mm (2 in.) equal leg angle section shall be added between deck beams to provide structural backup for the splices. All connections shall develop the full strength of the plate.

4. In order to minimize deck plate warpage during weld out, 0.9 mm (0.035 in.) welding wire spacers

may be placed on the deck beams prior to laying the deck plate.

5. If welding wire spacer is used, the deck plate should be in firm contact with the spacer prior to welding. If no spacer is used, the deck plate is to be in firm contact with the beams prior to welding.

6. Fabrication and welding procedures for the installation of deck plate shall cover weld sequence,

control of heat input, control of distortion in supporting beams, correction procedures, etc.

5.3.5.9 Grating

1. Steel grating shall be according to Structural Material Specification for CP6S and CP7S Complexes,

Ref. [14].

2. When fiberglass grating is specified, the type, size, and manufacture shall meet the requirements

of Structural Material Specification for CP6S and CP7S Complexes, Ref. [14].

3. Grating fasteners shall refer to Open Grid Flooring and Handrailing Specification for CP6S and CP7S Complexes, Ref. [17] or CONTRACTOR may submit a material type substitution request in writing to COMPANY Representative for approval. Grating studs shall be torqued per the Manufacturer’s specification. The fasteners shall be installed at locations specified on the drawings.

4. Grating shall be trimmed and fitted around equipment supports. Additional support brackets shall

be added as required.

5. Grating shall be installed after the support structure has been painted.

6. Pipe penetrations through grating shall be sleeved using Schedule 40 pipe. Pipe-to-sleeve annulus shall be large enough to allow passage of a flanged pipe spool. The sleeve shall extend a minimum of 100 mm (4 in.) above the grating.

7. Other penetrations that intersect four or more bearing bars shall be banded on all sides with pipe or rolled flat bar of the same thickness and depth as the bearing bars. All banding shall be seal-welded to all intersecting bearing and spacing bars.

8. Grating shall be continuously banded around all exposed edges. Ends of bar grating panels shall

be banded.

9. Stair treads shall be fabricated from the same type of grating as the landing it serves or shall be manufactured steel treads with abrasive nosing (e.g., Grip Strut). Each tread and the edge of the landing at the top of the stairs shall be fitted with a distinctive nonskid, leading-edge nosing (nosing shall be approved by COMPANY). When nosing is not an integral part of the stair tread, the nosing shall be installed after painting and galvanizing.

10. Welding in grating should be performed prior to galvanizing to the extent practical. Welds in grating after galvanizing due to repairs and design changes shall be touched up with approved cold galvanizing or COMPANY-approved equivalent.

11. Bar grating shall not be spliced. Repair sections for bar grating shall be a minimum of 300 mm (12

in.) wide and span beam to beam.

5.3.5.10 Holes and Penetrations

1. Penetrations of plate girder or deck beam flanges shall not be permitted. Penetrations of plate girder webs will be allowed if supported by design calculations. All such penetrations must be shown on the AFC drawings.

Company No._Rev. 200-22-ST-SPC-00007_00

23 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

2. Penetrations not shown on the AFC drawings shall not be permitted through structural steel

members without prior COMPANY approval.

3. Holes shall be drilled or punched and shall not be made or enlarged by burning unless followed by

machining away at least 3 mm (1/8 in.) of the material after burning.

4. Punching of holes shall not be used on plates that are more than 10 mm (3/8 in.) thick.

5. Other methods may be used if approved by COMPANY.

5.3.5.11 Stairways, Ladders and Handrails

1. Corners, edges, burrs, or rough spots on handrails, guards, etc. shall be ground or filed smooth. Handrails shall be fabricated such that weep holes are eliminated (by cutting holes in the post where midrails intersect). Should weep holes be cut, CONTRACTOR shall plug all weep holes by an approved method.

2. Connections between aluminum components and the steel support structure shall be as shown on

AFC drawings endorsed by COMPANY.

5.3.5.12 Cathodic Protection

CONTRACTOR shall prepare standoff ends, install, and weld out anodes at the locations specified on the AFC drawings and in accordance with Cathodic Protection Specification for CP6S and CP7S Complexes, Ref. [23]. No damaged anodes shall be installed.

5.3.5.13 Finishing of Surfaces

1. Edges of plates, structural shapes, and pipe ends determined to be sharp enough to cause potential paint cracks shall be rounded with a power disk grinder prior to applying paint. Burrs shall be removed from all edges in any case.

2. All items on the Contract drawings specified as galvanized shall be hot-dip galvanized in accordance

with the requirements of ASTM A123/A123M, Ref. [46].

3. The weight of the zinc coating shall average 763 g/m2 (2.5 oz/ft2) of actual area coated and no

individual specimen shall show less than 763 g/m2 (2.5 oz/ft2).

5.3.5.14 Rubber Goods

1. Shock cells, barge bumper posts, boat landing rubber strips, jacket leg closure diaphragms, grout packers, and other rubber goods shall meet the requirements specified in Structural Material Specification for CP6S and CP7S Complexes, Ref. [14]. Substitutions may be made if approved in writing by COMPANY.

2. Rubber diaphragm elements, when used, shall be removed from fixing ring mounts prior to welding the fixing rings to the jacket legs. Installation of the diaphragm components shall be according to instructions supplied by the Diaphragm Manufacturer.

5.3.5.15 Chain Link Fencing

Fence wire and fencing hardware shall meet the requirements specified in Structural Material Specification for CP6S and CP7S Complexes, Ref. [14].

5.3.5.16 Random Arc Strikes

Where evidence of random arc strikes exists, it shall be ground out, repaired, and inspected using a procedure supplied by CONTRACTOR for COMPANY endorsement.

Company No._Rev. 200-22-ST-SPC-00007_00

24 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

5.3.5.17 Post Weld Heat Treatment

1. CONTRACTOR is to advise COMPANY in writing if any weld procedure requires Post Weld Heat Treatment (PWHT) to be qualified in accordance with this Project Specification, Section 7. All welds or assemblies requiring PWHT shall be clearly noted on AFC and shop drawings.

2. When required, written procedures for heat treatment operations shall be prepared and submitted to COMPANY for endorsement before any such work is undertaken. Detailed sketches as to location of heating elements, recording elements, insulation, and weather protection systems shall be included within the procedures.

3. Welding of post weld heat treated items is normally not permitted. If welding of PWHT items are

requested by CONTRACTOR, CONTRACTOR shall provide a technical justification backed up by previous independent approved pre-qualification data to support the request and shall obtain written approval from COMPANY prior to welding.

5.3.5.18 Attachment of Equipment Skids

1. Equipment skids on plated deck shall be attached directly to the floor beams if any point on the skid is subject to uplift either during installation or operation. Attachment to deck plate shall satisfy the requirements of Section 5.3.5.8.

2. Equipment skids on grated decks shall be attached directly to the floor beams.

5.3.6 Assembly

5.3.6.1 General

1. Work should not be performed when the weather does not permit satisfactory workmanship or conditions prevent required inspection. COMPANY reserves the right to halt work under such circumstances.

2. CONTRACTOR shall provide any reinforcement and construction aids required during erection including but not limited to pad eyes and temporary braces. Stresses in the structure components and temporary bracing shall be limited to API RP 2A-WSD, Ref. [35] and AISC-ASD, Ref. [34] basic allowable during all stages of assembly and erection.

3. The site assembly procedures and methods, including details of temporary works, support points,

jacking points, and sling points shall be submitted to COMPANY for review before assembly.

4. Fabrication procedures shall conform to API RP 2A-WSD, Ref. [35], AWS D1.1/D1.1M, Ref. [64],

and this Project Specification.

5. Access manholes in the tubulars, legs, or box girders shall not be permitted without prior approval by COMPANY. The longitudinal seams of windows cut to facilitate fit-up at the end of braces shall be oriented 90 degrees to the longitudinal pipe seam. The transverse seam shall be located a minimum of 2 brace diameters from the joint. The transitions between longitudinal and transverse seams shall have minimum radius of 150 mm (6 in.). Plates covering access manholes and windows shall be flush with the outside diameter of the brace and joined using full penetration welds. Welds shall be ground smooth and subjected to the same inspection as the joint itself.

6. Copes and ratholes in stiffeners, diaphragms, and other structural members shall have a minimum radius of 50 mm (2 in.) or greater and shall be located as shown on the AFC drawings. Use of ratholes in other locations shall be subject to approval by COMPANY. Ratholes in closed structural members shall be closed by welding where possible. Where access makes closing out the rathole by welding impossible, a closing plate shall be used on both sides of the structural member.

Company No._Rev. 200-22-ST-SPC-00007_00

25 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

Ratholes are not allowed in primary steel. However, in order to facilitate the access for full penetration welds (e.g. flanges on the splice of plate girder), subject to COMPANY approval, where CONTRACTOR wishes to use the cope holes, these may be permitted:

• Minimum radius 25mm for member thickness up to 12.5mm.

• Minimum radius 50mm for member thickness 12.5mm and over.

The cope holes shall not be filled with weld metal, they shall be covered with plates of appropriate dimensions if required welded to an approved welding procedure. The fillet portions of all welds are to be returned through the cope hole and finished to a smooth radius to facilitate MT.

Ratholes in secondary steel shall not reduce the total web depth by more than 20 percent. All ratholes shall have a smooth finish and be fully coated. Closing plates shall be 100 percent sealed by a minimum 6 mm (1/4 in.) fillet weld using approved welding procedures.

7. CONTRACTOR shall prepare yard erection drawings showing methods and order of erection of the structures. These drawings shall include details of temporary erection aids, rigging configurations and components, lifting cranes, lifting limitations, equipment skidding limitations, and lifting sequences. These drawings and the supporting engineering calculations shall be submitted to COMPANY prior to the beginning of erection.

8. CONTRACTOR shall verify that the overall stability at any stage of erection is satisfactory. Calculations shall include the effects of all scaffolding, staging, welding, shelters, and environmental loads and shall be performed in accordance with Design of Deck Structures for Offshore Platforms Specification for CP6S and CP7S Complexes, Ref. [15].

9. Assembly of the structural steel shall proceed on a level and stable surface. CONTRACTOR shall submit details of fabrication site and loadout path foundation soils and proposed foundation, including soils reports, to COMPANY prior to the start of yard erection. Checks of blocking and levels shall be made on a monthly basis and after each setting of major structural or mechanical assemblies or if there is evidence of any instability of the supporting working surface. When any portion of the structure settles out of level exceeding 6 mm (1/4 in.), the steeled section shall be brought back into level by shimming the blocking under it or by other actions as required. Monthly level survey reports shall be given to COMPANY. Misalignment shall be corrected at all stages of erection.

10. Fitting of joints shall be restricted to machine or flame cutting and grinding. Any beveled edge that has been damaged shall be restored to the minimum tolerances. The fit-up of all joints shall be inspected by a Quality Control Inspector after completion of fit-up, but prior to any production welding. If the fit-up meets COMPANY requirements, the joint shall be clearly marked for satisfactory fit-up and initialed by Quality Control Inspector. Tack welds or welds to holding devices shall be in accordance with a prequalified tacking or welding procedure respectively.

11. All temporary attachments to the structure, such as scaffolding supports and other fabrication aids, shall be removed prior to loadout without damaging permanent structures. When removing temporary attachments, the attachment shall be cut off no closer than 3 mm (1/8 in.) to the permanent member, then ground flush. All weld and weld splatter shall be removed, and surfaces restored to a smooth, flush finish. After removing temporary member and grinding flush, these areas shall be magnetic particle inspected in accordance with COMPANY-approved procedures.

12. Temporary welds shall not be located closer than 305 mm (12 in.) from structural joints unless approved otherwise by COMPANY. Where attachments are placed within the 305 mm (12 in.) zone, the attachment is to be removed as described above and the attachment area subjected to 100 percent ultrasonic and magnetic particle inspection (MPI) examination and a nondestructive examination (NDE) report generated.

Company No._Rev. 200-22-ST-SPC-00007_00

26 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

13. If CONTRACTOR proposes to employ heat-straightening procedures during fabrication, Contractor

shall submit the heat-straightening procedures to COMPANY for review and endorsement.

5.3.6.2 Dimensional Tolerances

1. Allowable fabrication tolerances shall conform to the following (in order of precedence):

a) This Project Specification.

b) API RP 2A-WSD Ref. [35], API SPEC 2B (for structural steel pipe) Ref. [37], AISC-ASD Ref.

[34] and ASTM A6/A6M (for rolled shapes) Ref. [50], and AWS D1.1/D1.1M Ref. [64].

c) NORSOK M-101, Ref. [75], Annex E “Fabrication Tolerances” shall be used when no

tolerance is specified by this Project Specification or the above standards.

d) Tolerances not covered by this Project Specification and the above standards shall be

approved by COMPANY.

2. The following lists COMPANY tolerances that supersede the standards listed in Item (1) above:

a) Water holding valleys in excess of 6mm (1/4 in.) deep should not be allowed in the deck

plate between any two deck beams.

b) Handrails shall be fabricated so that, when erected, the top rail is level, and the post is plumb. Removable handrail panels shall fit snugly. Removable handrail panel posts shall be bolted through the sockets to prevent play.

c) Landing elevations and landing and stairway locations (horizontally) shall be within 12 mm (1/2 in.) of AFC drawing dimensions. The vertical distance between stair threads in one flight shall not exceed 3 mm (1/8 in.). Differences between elevations of grating at seams shall not exceed 3 mm (1/8 in.).

d) Girder flange shall have a width tolerance of +6 mm (1/4 in.) or −3 mm (1/8 in.).

e) Skid beams for drilling rigs require tighter tolerances than regular girders

Flange warpage and tilt

: 11/2 mm (1/16 in.)

Top flange levelness

: 3 mm (1/8 in.)

Parallel

: 3 mm (1/8 in.)

Flatness of web

: 3 mm (1/8 in.) or depth/150, whichever is smaller

Width of flange

: 3 mm (1/8 in.)

f) Web stiffeners for beams and plate girders shall be located in the position shown on the AFC

drawings within 6 mm (1/4 in.) of the design location.

g) Stiffener for beams and plate girders will require the tolerances shown in Figure 5.1 and

Table 5.1 below:

Company No._Rev. 200-22-ST-SPC-00007_00

27 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

Figure 5.1: Stiffener Tolerances

Table 5.1: Stiffener Tolerances

Controlled Parameter

Notation

Tolerances

Offset

Out of Straightness

Out of Square

Out of Vertical

Out of Position

S1

S2

S3

S4

S5

6 mm (1/4 in.)

3 mm (1/8 in.)

3 mm (1/8 in.)

6 mm (1/4 in.)

6 mm (1/4 in.)

Out of Vertical and Out of Position S4 + S5

6 mm (1/4 in.)

h) Pad eye and lift trunnions shall be placed within one degree of the design orientation and

within 13 mm (1/2 in.) of the design location, as shown on AFC drawings.

i) The actual location of wall thickness changes as compared to the location indicated on the

AFC drawings shall be within the following tolerances:

Plate girder, beam, and brace

: 25 mm (1 in.)

Deck leg

Pile

: 50 mm (2 in.)

: 150 mm (6 in.)

j) The overall length of piling shall be within 150 mm (6 in.) of the length shown on the AFC

drawings.

k) The centers of the top and bottom of all conductor guides, sleeve pile guides, and skirt pile guides and supports shall not deviate more than 6 mm (1/4 in.) from that specified on AFC drawings.

l) Equipment support locations shall not exceed a tolerance of 6 mm (1/4 in.).

Company No._Rev. 200-22-ST-SPC-00007_00

28 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

m) The centerline point of permanent openings shall be within 13 mm (1/2 in.) of the design point. The size of the opening shall be within 6 mm (1/4 in.) of the design opening size.

n) Centerline dimensions between skid beams shall not vary more than 10 mm (3/8 in.) from those shown on the AFC drawings, and they shall not vary more than 6 mm (1/4 in.) vertically. Abutting surfaces of the skid beam top flanges shall be flush within 2 mm (1/16 in.). The timber shall be planed smooth on all four sides and the difference in elevation from one timber face to the next adjoining timber face shall be no more than 5 mm (3/16 in.).

o) Anodes shall be located within 150 mm (6 in.) of the location shown on the AFC drawings.

p) All heliport fencing shall be taut between panels. The maximum sag between panels shall

be 13 mm (1/2 in.) under a load of 91 kg (200 lb) at the panel center.

q) Skids shall conform to the tolerances specified on AFC drawings and shall be level within 6

mm (1/4 in.) between any two corners after installation.

r) Crane pedestals shall be plumb within 1/1000th of their height, or the Crane Manufacturer’s

specifications, whichever is the tightest tolerance.

5.3.6.3 Dimensional Control Procedures

1. CONTRACTOR shall develop a detailed dimensional control procedure for review by COMPANY prior to start of construction. The procedure shall describe the methods to be used for measuring dimensions and maintaining the tolerances specified herein. Emphasis should be placed on interfaces between assemblies and components.

2. Dimensional surveys shall be performed immediately after fit-up and after final welding. Additional dimensional survey shall be performed by a certified surveyor, if requested by COMPANY.

3. As-Built dimensions and resulting fit-up of the following components shall be surveyed and

documented by CONTRACTOR and accepted by COMPANY prior to loadout.

4. Base of topsides and top of jacket.

5. Base of modules and support points on deck.

6. All measurement equipment shall be calibrated at a minimum frequency of once every 6 months. Calibration documentation shall be submitted to COMPANY for review. All measurements shall be corrected for temperature variation and be proven to the satisfaction of COMPANY. Additional calibration checks shall be made if requested by COMPANY.

7. Tolerances shall be based on theoretical setting out points and the centerline of the structure referenced to permanent approved datum points, corrected to the reference temperature (16C), unless otherwise specified.

8. CONTRACTOR shall set out all primary datum points on the structure using accepted engineering surveying techniques consistent with achieving the tolerances required by this Project Specification. Permanent survey stations shall be properly constructed and protected from disturbance. Additional reference points shall be provided to permit monitoring and re- establishment of the permanent stations.

9. CONTRACTOR shall provide signed dimensional drawings to COMPANY.

10. Equipment skids on grated decks shall be attached directly to the floor beams.

Company No._Rev. 200-22-ST-SPC-00007_00

29 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

5.3.7 Workmanship

Workmanship shall be in accordance with the following requirements:

1. Steel work shall be well formed to shape and size, with true lines and smooth surfaces.

2. All members shall be accurately fabricated and assembled plumb, square, and level in

accordance with the tolerances set forth in this Project Specification.

5.3.8 Vortex Shedding

1. CONTRACTOR shall take measures to protect members and appurtenances that are susceptible to vibration due to vortex shedding while at the fabrication yard. Such measures may consist of hanging weights from, or wrapping chain, wire, or rope around, or adding temporary midspan ties to, the susceptible members.

2. CONTRACTOR should refer to Design of Deck Structures for Offshore Platforms Specification for CP6S and CP7S Complexes, Ref. [15] for the calculation method for predicting critical wind speed for each component.

5.4 CONTRACTOR Engineering

1. CONTRACTOR shall provide all required engineering to fabricate, assemble, and load out the component structures. Specific engineering deliverables for intermediate review and staged reviews are specified in the Coordination Procedures (part of Contract Documents).

2. All engineering shall conform to the requirements of Specification for Design of Jacket and Piles for CP6S and CP7S Complexes, Ref. [21] & Design of Deck Structures for Offshore Platforms Specification for CP6S and CP7S Complexes, Ref. [15].

5.5 Lift and Rigging Requirements

Lift of fabricated components and the required rigging shall be in accordance with COMPANY specifications or per the applicable industry specifications.

5.6 Weight Measurement

1. Weighing requirements for all components, equipment, and bulks shall be in accordance with Weight

Control Procedure for Greenfield, Ref. [31].

2. Prior to loadout, CONTRACTOR shall weight all platform modules, module support frames, decks,

bridges, flares, lifted jackets, and any other items required in the Contract.

3. All other activities related to weight and weight control shall follow Weight Control Procedure for Greenfield, Ref. [31] and Weight Control Procedure for Vendor for CP6S and CP7S Complexes, Ref. [32].

4. Weight control activities (e.g., monitoring of any additional weight added or removed) shall continue

between final weighing and sail-away.

5.7

Identification and Marking

1. All major load bearing plates, beams, tubulars, and structural pipes that require traceability (see Structural Material Specification for CP6S and CP7S Complexes, Ref. [14]) shall have the mill heat numbers transferred by steel stencil (hard stamp) prior to being cut into smaller pieces. The data shall be recorded as part of the material traceability requirements.

2. All pipe from other than ASTM A36/A36M, Ref. [47] material shall be painted in accordance with the general provisions of ASTM A 6/A6M, Ref. [50]. CONTRACTOR shall provide COMPANY with color

Company No._Rev. 200-22-ST-SPC-00007_00

30 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

codes if different from ASTM A6/A6M, Ref. [50], or where additional color codes are required to differentiate between grades of steel.

3. Each length of structural beam, pipe, plate, or tubular can that is rolled from plate shall be marked on one end by paint in 25 mm (1 in.) minimum high letters. Paint identification will include, but is not limited to, the following:

• Metal

• Grade

• Heat and Plate Number(s)

• Can Dimensions (diameter, wall thickness, length of can)

• Manufacturer’s Name

4. All tubular cans shall be marked additionally by a 50 mm (2 in.) wide circumferential strip around the

exterior surface of both ends. The color code scheme is to be determined by the Fabricator.

5. Flood and vent manifolds, plus all piping, shall be identified and marked as to function and

compartment location.

5.8 Construction Site Foundation Requirements

5.8.1 General

The requirements of this Section are applicable to foundations for structure during fabrication and loadout, including skidways and wharfs

5.8.2 Site Investigation

1. CONTRACTOR shall have soil strength parameters and other engineering parameters for calculating bearing and pile capacities from in-situ tests and laboratory tests from a site investigation. A copy of the Site Investigation Report shall be provided to COMPANY.

2. The site investigation shall have adequate laboratory tests on good-quality, undisturbed samples or

in-situ tests. The following soil tests are acceptable for cohesive and cohesionless soil:

Table 5.2: Site Investigation Test

Soil Type

Laboratory Test

In-Situ Test

Cohesive soils

Unconsolidated-undrained triaxial test

Cone penetrometer test

Miniature vane shear test

Vane shear test

Cohesionless soils

Drained triaxial test

Cone penetrometer test

Standard penetration test

3. Laboratory tests shall include sufficient index and physical properties tests to adequately

characterize soil stratigraphy.

Company No._Rev. 200-22-ST-SPC-00007_00

31 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

5.8.3 Foundation Design and Assessment

1. Platform components shall be supported on piled foundation during final assembly and skidding loadout unless CONTRACTOR can demonstrate to COMPANY’s satisfaction that the foundation settlement is within the acceptable fabrication and loadout tolerances.

2. Bearing capacities for shallow foundations shall consider eccentric loads, and the minimum factor

of safety shall be 2.0 and in accordance with API RP 2A-WSD, Ref. [35].

3. Working capacity of individual piles shall be designed with a minimum factor of safety of 2.0 and in

accordance with API RP 2A-WSD, Ref. [35].

4. Foundation design and assessment shall be in accordance with API RP 2A-WSD, Ref. [35].

5. Shallow foundations shall not be used for soil with a potential of punch-through failure (e.g., soil

with a thin, firm crust that overlies a soft clay).

6. CONTRACTOR shall demonstrate to COMPANY that foundation and wharf condition are consistent with capacity calculations. Any corrosion or other damage shall be repaired, or foundation/wharf shall be demonstrated acceptable via an engineering strength assessment supported by a recent inspection report.

5.9 Documentation Requirements

1. CONTRACTOR shall be responsible for reviewing all documentation provided by COMPANY and for noting any discrepancies and/or omissions as described in the Coordination Procedures.

2. CONTRACTOR is also responsible for providing COMPANY with the following:

a) Fabrication and erection plans, including sketches, estimated weight of each major lift and roll-

up, and erection sequence/procedure.

b) All major lift plans, including detail analysis and procedures.

c) Loadout plan, including detail analysis and procedures.

d) Material traceability, including mill certificates and all construction drawings with the associated

mill certificate tag for each component or segment of the component.

e) Welding Procedure and QA/QC plans and procedures as per this specification, Section 7.

Company No._Rev. 200-22-ST-SPC-00007_00

32 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

6 QUALITY ASSURANCE PROVISION

6.1

Inspections

6.1.1 General

1. All materials shall be subjected to inspection in accordance with Project Quality Plan.

2. COMPANY may use any method of inspection necessary to establish quality control and ensure

adherence to specific offshore platform fabrication procedures.

3. Materials and workmanship will be subject to inspection at any time by COMPANY. All defective or improperly placed materials shall be removed and replaced by materials satisfactory to COMPANY. This applies to all material before or after the material has been placed in the work.

4. When, in the judgment of COMPANY, any work area or section should be inspected, CONTRACTOR shall thoroughly clean it of all excess and waste materials, such as sand, slag, weld spatter, used rods, etc., and allow sufficient time for it to be properly inspected. CONTRACTOR shall furnish, install, and maintain in a safe operating condition the necessary scaffolding, ladders, walkways, adequate lighting, etc., for a safe and thorough inspection by COMPANY.

5. COMPANY will approve all changes in plans, material purchases, and services not included in the

Project Specifications, and COMPANY will inspect work performed by CONTRACTOR.

6.1.2 Inspection Requirements

1. Minimum inspection points shall be in accordance with Table 6.1. CONTRACTOR shall provide all

inspections listed in the table.

2. Specific NDE requirements shall be in accordance with this Project Specification, Section 10.

Table 6.1: Inspection Requirements

Item

COMPANY (1)

CONTRACTOR (1)

W

R

S

G

W

R

S

G

Mechanical Test at the Mill

Mill Sheet Review at the Site

Receiving Inspection of Material

•

Mill Heat Number Transfer (5) Plate Edge Inspection after Cutting (3) (6) Fit-up Inspection

Gauge Inspection

•

•

•

•

•

•

•

•

•

•

•

•

•

•

•

•

•

•

•

•

•

• •

• •

• •

• •

• •

• •

• •

• •

• •

• •

•

•

•

•

Visual Inspection after Welding (3) Nondestructive Examination (4) Dimensional

•

•

•

•

•

•

•

•

Company No._Rev. 200-22-ST-SPC-00007_00

33 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

Item

COMPANY (1)

CONTRACTOR (1)

W

R

S

G

W

R

S

G

Pressure Test

Painting Inspection

Final Inspection

Seafastening Inspection

Table 4 Notes:

1

Definitions:

•

•

•

•

•

•

•

•

•

•

•

•

•

•

• •

• •

• •

• •

2

3

4

5

6

W= Witness

R= Record review S= Spot check G= General surveillance

Inspection stages (hold points) shall be shown in a fabrication sequence diagram (FSD) prepared by CONTRACTOR.

COMPANY Representative to witness 100% of activity shown for all primary members and makes inspections required to hold points shown in fabrication structural drawings.

“S” includes Ultrasonic Testing (UT) calibration, procedure, and fieldwork check; “R” includes 100% review of radiographs and reader sheets, UT and magnetic particle testing (MT) reports, and weld map review.

Material traceability.

Primary to primary member T, K, Y joints and erection stage tubular butt joints. Primary members are defined as members manufactured from Type I through III material.

6.2 Testing

6.2.1 Testing of Jacket Members

COMPANY Representative shall witness CONTRACTOR-supervised performance of all pre-loadout or/and post-loadout tests and inspections. The following tests shall be included:

1. Jacket legs and skirt pile guides shall be drifted (e.g., the internal diameters checked with a

template) to ensure their straightness after all welding is completed prior to Loadout.

a) The template diameter shall be at least 6 mm (1/4 in.) larger than the pile diameter.

b) The drifting shall be performed after welding of shim plates and braces is completed.

c) When jacket legs have been used for support during loadout, the external diameter of those

legs shall be re-tested.

2. Each pile section shall be drifted to ensure straightness and that internal diameters are not

excessively oval, obstructed, or in any way present a hindrance to the installation of piles.

3. When permanent buoyancy or

installation temporary buoyancy (launch/upending) is required for installation, jacket legs shall be pneumatically tested prior to loadout to ensure their watertightness.

transportation or

for

a) Jacket legs (including the closures) shall be individually and independently tested with compressed air to a pressure of expected (dive) depth plus 10 percent or 103 kPag (15 psig), whichever is larger. This pressure shall be maintained for a period of 2 hours without further

Company No._Rev. 200-22-ST-SPC-00007_00

34 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

addition of air or loss of pressure, making due allowance for ambient temperature changes. Leak testing of jacket legs and buoyancy tanks with 1.5 bars pressure are required.

b) The use of water to reduce the amount of compressed air will require COMPANY approval.

c) CONTRACTOR shall examine all joints for tightness using soap solution or other indicator approved by COMPANY. All leaks or other defects discovered by the testing and caused by faulty workmanship shall be repaired by CONTRACTOR, in accordance with the repair procedure specified in this Project Specification, Section 11.

d) After completing the repair, CONTRACTOR shall retest the repaired member until a successful

test is attained to the satisfaction of COMPANY.

e) Once successful testing has been completed, the pressure shall be reduced to 35 kPag (5 psig) and maintained at this value, making due allowance for temperature changes and without the addition of further air, for the duration of the loadout, sea fastening, transportation, and lifting/launch procedures.

4. Prior to testing, CONTRACTOR shall prepare written test methods, including pressure monitoring,

and submit them to COMPANY for endorsement.

6.2.2 Pressure Testing of Grout Systems

1. CONTRACTOR shall prepare a plan for testing and pressure monitoring of the grout system and

submit it to COMPANY for endorsement prior to testing.

2. All grout lines shall be pressure tested, at a pressure of 1.5 times the working pressure, for not less

than 30 minutes. All leaks shall be repaired.

3. All grout lines shall be internally cleaned prior to testing and loadout to remove weld slag and other

debris.

4. All grouting valves shall be lubricated, and test operated before loadout to ensure that the valve

control risers and valves operate smoothly and freely.

a) Valve handles shall be positioned according to the grout plan.

b) After testing, valves shall be checked to ensure that protective caps or other obstructions that

can hinder proper operation are not present.

5. All grout packers shall be tested in accordance with Manufacturer recommendations.

6. All subsea air or grout line connectors shall be test-fitted in the yard with equipment to be used

offshore.

6.2.3 Pressure Testing of the Flooding System

1. All flood lines shall be pressure tested at 1.5 times the working pressure for not less than 30

minutes.

a) For small jackets with the flooding system consisting solely of a nipple and flood valve, the test

shall be performed at the jacket leg test pressure of 103 kPag (15 psig).

b) All leaks shall be repaired in accordance with an approved repair procedure.

2. All flood lines shall be internally cleaned prior to testing and loadout to remove weld slag and other

debris

3. All flooding valves shall be lubricated, and test operated before loadout to ensure that the valve

control risers and valves operate smoothly and freely.

Company No._Rev. 200-22-ST-SPC-00007_00

35 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

a) After testing, the valves shall be checked to ensure that they are properly oriented according to

the flooding plan.

b) Valves shall be checked to ensure that the protective caps and other obstructions that may

hinder proper operation are not present.

4. Where applicable, functional operation of the pneumatic flooding control panel shall be performed

to ensure proper operation.

5. Prior to testing, CONTRACTOR shall prepare test methods and submit them to COMPANY for

endorsement.

6.2.4 Test Fitting of Appurtenances

1. Prior to loadout, CONTRACTOR shall test fit all platform components that are shipped loose and designated as field installed. These components include, but are not limited to, the following:

a) Barge bumpers

b) Stairs

c) Boat landings

d) Handrails

e) Grating

f) Helideck

g) Deck Cranes

h) Large Spool Pieces

2. After the fit has been verified in the fabrication yard, the items shall be removed and prepared for shipment. Handrails and similar other items shall be stamped or metal tagged to show their test- fitted location.

3. All yard test fits shall be photographed. The photographs shall be sent offshore and be provided

to the Installation CONTRACTOR.

6.2.5 Plated Surfaces and Drains

1. Plated decks shall be flooded and checked for ponding. If deviations of the plated surface are larger than the tolerances specified Section 5.3.6.2, CONTRACTOR shall correct the problem. At COMPANY’s option, drains in lieu of plate straightening may be used as the corrective action. COMPANY shall approve all repair procedures before the repair is undertaken.

2. Drain troughs and drain lines shall be checked for leaks and proper drainage. CONTRACTOR shall prepare a test method and submit it to COMPANY for endorsement prior to testing of the drains.

Company No._Rev. 200-22-ST-SPC-00007_00

36 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

7 WELDING

7.1 Welding – General

1. All structural welding shall be in accordance with AWS D1.1/D1.1M, Ref. [64], amended and supplemented by the welding section of API RP 2A-WSD, Ref. [35], this Project Specification, and the AFC drawing requirements. All welds shall be full penetration welds, unless detailed otherwise on AFC drawings.

2. Welding and other criteria covered by this Project Specification shall meet or exceed the requirements of any codes referenced herein or in the Contract Documents. In case of conflict, the specific requirements stated herein shall govern over referenced specifications. Any such conflict between the requirements of this Project Specification and related codes, standards, drawings, contract document, etc. shall be referred to COMPANY for written clarification and resolution prior to fabrication.

3. CONTRACTOR shall not make any assumptions regarding information not furnished by

COMPANY. CONTRACTOR is required to obtain all necessary documentation from COMPANY.

4. CONTRACTOR’s base technical proposal in response to the ITT Package shall include full

compliance with this Project Specification.

5. CONTRACTOR shall list and fully describe all modifications or deviations from this Project Specification and the related codes in an alternate technical proposal to the ITT Package. Alternate technical proposals shall include all relevant technical information, for each medication or deviation, such that the technical merit of each modification or deviation can be assessed at the bid stage, on a case-by-case basis.

6. The Lowest Anticipated Service Temperature (LAST) for the selection of materials has been based on the air and seawater temperatures given in the Section 6.11 of Greenfield Topside Structural Design Basis, Ref. [25].

For the purpose of this Specification LAST shall be taken as: LAST = 0oC

The above LAST temperature is a conservative value, since as per report OMQ011 (181571_1_R3) _Part 2_Updated, “Updated Metocean Offshore Qatar – Fugro”, Ref. [8], Table 3.5.1, the lowest anticipated service temperature is 16.0 degree Celsius, occurring in all year season.

LAST is to be used for the general selection of materials unless local specific operating conditions dictate otherwise.

Impact testing for toughness classes containing CV2 requirements (e.g. CV2, CV2X, CV2ZX, CV2Z4 and CV2Z5) shall be conducted at 20oC below LAST on Class A steels per API RP 2A- WSD.

7. CONTRACTOR shall prepare and submit a complete set of WPS with supporting PQR for review

and approval by COMPANY prior to fabrication.

8. CONTRACTOR shall prepare a WPS register that identifies all WPS and associated PQR and the locations in the structure where the procedures shall be used. The WPS register shall include:

a) WPS and supporting PQR

b) Welding process

c) Consumables (AWS Classification and brand name/Manufacturer and size)

d) Material grade

e) Joint type

Company No._Rev. 200-22-ST-SPC-00007_00

37 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

f) Preheat and interpass temperature proposed

g) Thickness to be qualified and thickness range qualified

h) Position for PQT and positions qualified for fabrication

i) Mechanical tests to be performed

j) CVN/CTOD test temperatures, as applicable

k) NDE to be performed

l) Start and finish date for welding and testing

9. The WPS and supporting PQR shall include all essential and nonessential variables.

10. Only COMPANY-approved WPS shall be used in fabrication.

7.1.1 Tack Welds

1. All members shall be well-fitted and firmly tacked into place before welding.

2. Tack welding, including tack welding of temporary attachments, such as scaffolding supports and tie-downs, shall be performed according to a qualified and COMPANY-approved WPS and shall only be performed by qualified Tack Welders or qualified Welders.

7.1.2 Gaps and Buttering

1. As part of the WPS, CONTRACTOR shall include a procedure for repair of wide gaps. The procedure shall be in accordance with AWS D1.1/D1.1M, Ref. [64] and this Project Specification.

7.1.3 Seal Welding

1. All contacting steel surfaces, except grating, or where otherwise shown on approved drawings, shall be seal-welded by continuous fillet welds to prevent corrosion between the contacting surfaces. Seal welds shall be made in accordance with AWS D1.1/D1.1M, Ref. [64] using a COMPANY-approved WPS.

2. When seal welding is not practicable, boxing plates shall be used to completely seal inaccessible

surfaces from the outside atmosphere.

3. Liquid Steel, Caulk, Putty, Epoxy Compounds, or Solder shall not be used.

7.1.4 Fillet and Partial Joint Penetration (PJP) Welds

Root openings in excess of 5 mm (0.20 in.) shall be corrected by converting the joint to a CJP groove weld. The weld groove between the fillet weld and CJP weld shall be suitably transitioned from a fillet to a PJP, then transitioned from a PJP to a CJP.

7.1.5 Weld-Through Primers

1. Use of weld-through primers shall require written COMPANY approval prior to the start of fabrication.

2. When weld-through primers will be used during fabrication, they shall be included in the WPS

qualifications.

3. DFT of the primer shall be included on the PQR for qualification of the weld-through primer.

4. Weld-through primer qualification testing shall be in accordance with this Project Specification.

7.1.6 Backing Bars and Runoff Tabs

1. Backing bars, rings, or strips shall not be used for any primary structural steel, except ceramic

backing material may be used when qualified in accordance with this Project Specification.

Company No._Rev. 200-22-ST-SPC-00007_00

38 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

2. Backing may only be used for non-primary structural steel components; however, all backing shall

be removed.

3. Backing proposed to be left in place shall be approved by COMPANY. In this case, the backing shall not interfere with the other connections or generate a stress riser. Additionally, backing that remains shall be entirely seal welded and traceable to the MTC.

4. Runoff tabs may be used for fabrication but shall be removed upon completion of the weld. The

ends of the weld shall be ground smooth and flush.

7.2 Approved Welding Processes

1. The following are approved welding processes:

a) Shielded metal arc welding (SMAW)

b) Submerged arc welding (SAW)

c) Gas metal arc welding (GMAW) RESTRICTED

d) Flux-cored arc welding (FCAW)

e) Gas tungsten arc welding (GTAW)

2. The short circuit arc GMAW process (GMAW-S) shall be used only for welding tertiary structural

items such as handrails, except as indicated in Item (3) below for root pass welding.

3. GMAW-S is also acceptable for root passes in primary structural welds when the remainder of the

weld is made from one or both sides using SAW, FCAW, or SMAW.

4. Modified short arc GMAW (i.e., suffices as STT, RMD, or similar) shall be considered a GMAW-S

process.

5. FCAW-SS for other than tertiary shall obtain COMPANY approval include PQR qualification prior to

use.

7.3 Welding Consumables

7.3.1 General

1. The welding consumables used to weld steels shall have been tested and certified by Manufacturer to meet or exceed the base material CVN test temperature. This shall be supported by the Material Test Report from Manufacturer.

2. The number of different consumables shall be minimized.

3. Welding consumables shall be supplied with Manufacturer’s Material Test Reports verifying that

they are low-hydrogen type electrodes and wire/flux.

4. All consumables used for welding primary steel shall conform to testing of each filler metal Manufacturer’s production lot as defined in AWS A5.01M/A5.01, Ref. [56], in conformance with the following:

a) Class C3 or C4 for SMAW electrodes

b) Class S3 for solid GMAW and SAW electrodes

c) Class T3 for FCAW

d) Class F2 for SAW fluxes

Level of testing shall be according to Schedule 4 of AWS A5.01, Ref. [56] as a minimum (each lot)

Company No._Rev. 200-22-ST-SPC-00007_00

39 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

7.3.2 Low-Hydrogen Welding Requirements

1. Low-hydrogen welding consumables shall be used for all welds.

2. Diffusible hydrogen testing of all SMAW, SAW, and FCAW consumables shall be performed. These consumables shall produce weld metal with ≤ 8 ml/100 g of diffusible hydrogen per deposited weld metal, as determined by ISO 3690, Ref. [71] or AWS A4.3, Ref. [55].

3. Additional diffusible hydrogen testing of consumables during construction shall be performed if

requested by COMPANY to confirm the following:

a) Purchased low-hydrogen electrodes meet specification requirements.

b) Field electrode handling practices deliver the diffusible hydrogen level requirements of this

Project Specification.

7.3.3 Consumables Storage and Handling Procedure

1. CONTRACTOR shall prepare and submit a Consumables Storage and Handling Procedure for COMPANY review and approval. The Procedure shall include storage and handling requirements for electrodes, flux, strip, bare wire, coated wire, and cored wire, where used.

2. Unless otherwise specified in Manufacturer’s recommendations, consumables shall be consumed immediately after opening, within Manufacturer’s specified number of hours. Alternatively, electrodes may be stored in a holding oven at a temperature of 121ºC (250ºF) or may be held in a heated portable rod oven.

7.3.4 Fluxes and Submerged Arc Welding (SAW)

1. CONTRACTOR shall have heating ovens equipped to heat the welding rods and welding fluxes,

and to sustain their required temperature, as specified by Manufacturer.

2. SAW flux shall not be reused from the floor or after exposure to dampness.

3. For SAW weldments, recycled, crushed slag shall be prohibited.

4. SAW flux from the plate (not the shop floor) may be reused, provided it is dry and immediately

collected and deposited into a heated hopper.

5. SAW flux recovery and storage system shall consist of vacuum recovery at the welding head with

subsequent magnetic and fines separation and heated holding ovens.

6. The SAW flux shall be stored at the temperature recommended by Manufacturer.

7. The traceability of SAW flux to Manufacturer and brand shall be maintained until it is consumed.

7.3.5 Electrodes

1. Cellulosic Electrodes are Strictly Forbidden.

2. Welding electrodes removed from heating ovens or portable heated rod ovens shall be used within

the allowable time stated by Manufacturer.

3. Welders shall keep all electrodes in a heated container or carrying box after removal from a heating

oven.

7.3.6 Wire Spools

1. FCAW consumables shall be controlled in accordance with the COMPANY-approved Consumable

Storage and Handling Procedure.

Company No._Rev. 200-22-ST-SPC-00007_00

40 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

2. Unused or partially used welding wire spools shall be returned to a warm holding facility at the end

of the day.

3. Consumable Storage room shall be approved by COMPANY inspector and requirements defined in

Consumable Storage and Handling Procedure.

4. Spools of opened FCAW or SAW wire shall be dated and stored in accordance with approved

Consumable Storage and Handling Procedure.

5. FCAW, GMAW, and SAW wire spools and coils shall be protected from rain and moisture during

production welding.

7.3.7 Consumable Identification

1. All welding consumables shall be properly identified up to time of use.

2. Each welding electrode and rod shall have distinguishing markings.

3. If identification is destroyed, then the consumables shall be discarded and replaced with properly

identified materials.

4. Welding wire spools shall be tagged with the electrode identification at all times during welding and

storage.

5. Wire spools shall be stored in cabinets with supplied wrappers intact, and partially used spools shall

be identified before being replaced in the cabinet.

6. In no case shall rusty or unidentified electrodes or wire be used.

7.4 FCAW Requirements

The following requirements shall apply to both self-shielded (FCAW-SS when approved by COMPANY) and gas-shielded (FCAW-GS) flux core arc welding:

1. All FCAW consumables shall be low-hydrogen type, as tested and certified by the Consumable Manufacturer and shall conform to AWS A5.20/A5.20M, Ref. [61] and AWS A5.29/A5.29M, Ref. [63] optional supplemental diffusible hydrogen designator H8.

2. Flux-cored wire shall be kept clean and dry prior to use and at all times while on the wire feeder. Wire that has any signs of rust or contamination shall be discarded. FCAW consumables shall be controlled in accordance with the COMPANY-approved Consumable Storage and Handling Procedure.

3. Maximum bead width and layer thickness shall be controlled for all FCAW welding to ensure adequate toughness of the weld and HAZ. Bead width and layer thickness shall be recorded on the PQR and shown on the WPS.

4. The maximum wire diameter for out-of-position welding (3G, 4G, 5G, and 6G) shall be as shown in

the table below.

Table 7.1: Maximum Wire Diameter

Thickness

Max Diameter for Gas Shield

Max Diameter for Self-Shield

< 10mm (0.40 in.)

1.0mm (0.04 in.)

≥ 10mm (0.40 in.)

1.5mm (0.06 in.)

2.0mm (0.08 in.)

2.0mm (0.08 in.)

Company No._Rev. 200-22-ST-SPC-00007_00

41 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

5. The flat position and horizontal positions (1G and 2G) shall be limited to 2.5 mm (0.1 in.) maximum

wire diameter.

6. Where the required Charpy test temperature is below −20°C (−4°F) or where CV2 materials are welded, the FCAW electrodes shall have the MJ suffix (e.g., E7X-T1MJ). Alternatively, CJ suffix can apply if the product is granted by Manufacturer with Charpy test temperature at -40oC (that is J designation); this also will bring compliance to API RP 2A Table 13.1, Ref. [35] or lower using a shielding gas with designator “C” in the relevant AWS Specification, Ref. [57] to Ref. [63].

7. Consumables for the FCAW-SS process shall require COMPANY approval. This will be handled

through the formal WPS/PQR review and approval process.

8. The FCAW welding consumables shall be tested and certified using gases having the same

designator “C” or “M” as used in fabrication.

9. FCAW-SS may be used alone or in combination with other processes. However, any welding procedure using a combination of FCAW-SS as one of the weld metals shall meet the requirements of AWS D1.1/D1.1M:2020 clause 6.28 “Combining FCAW-S with Other Welding Processes in a Single Joint, Ref. [64] and AWS D1.8/D1.8M, Ref. [65], Annex B “Intermix CVN Testing of Filler Metal Combinations”; however, the CVN test temperature and absorbed energy requirements shall be in accordance with this Project Specification.

10. Any repairs made to FCAW-SS weldments shall only be performed by FCAW-SS process. Any

exemption to such requirements is subjected to prior COMPANY approval.

7.5 Welding Procedure Qualification

7.5.1 General

1. All WPS shall be qualified in accordance with AWS D1.1/D1.1M, Ref. [64] and the additional

requirements of this Project Specification.

2. A COMPANY-approved independent testing laboratory shall perform qualification tests in

accordance with AWS D1.1/D1.1M, Ref. [64] and this Project Specification.

3. WPS with supporting PQR and the results of all qualification tests shall be submitted to COMPANY for review and approval. PQR performed for COMPANY, with failed mechanical test results, shall be reported.

4. Welding procedures shall be qualified by NDT and mechanical testing.

5. Prequalified procedures as defined by AWS D1.1/D1.1M, Ref. [64], Section 3, “Prequalification of WPSs” shall not be permitted, with the exception of tertiary members welded to themselves or welded to secondary members.

6. Records of previous qualification for a welding procedure may be submitted for approval in lieu of new qualifications and may be accepted if all requirements of this Project Specification are met. COMPANY may approve previously qualified PQR or may require additional testing, even if all requirements of this Project Specification are met.

7. Mechanical testing shall include tensile, bend, CVN, hardness, and macro-section tests in

accordance with AWS D1.1/D1.1M, Ref. [64] and this Project Specification.

8. Essential variables for welding procedure qualifications shall be in accordance with AWS

D1.1/D1.1M, Ref. [64] and this Project Specification.

9. CVN testing shall be performed for each welding position to be used in production. AWS D1.1/D1.1M, Ref. [64], Table 6.7 “PQR Supplementary Essential Variable Changes for CVN Testing Applications Requiring WPS Requalification for SMAW, SAW, GMAW, FCAW, and GTAW,” variable

Company No._Rev. 200-22-ST-SPC-00007_00

42 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

6 for “Position” shall not apply to welding qualifications that are in accordance with this Project Specification.

Qualification using test plate shall have impact tested at the position where it is qualified (e.g., 2G, 3G, 4G and 1G in case SAW mechanized). Qualification using test pipe (e.g., 5G, 6G, or 6GR position) the CVN specimens shall be extracted from 3 and/or 9 o’clock in accordance with AWS D1.1/D1.1M:2020, Figure 10.14.

When two different AWS D1.1 material group are joined and CVN tested at both HAZ, it will qualify each group of materials welded to itself and their combination

10. The actual values of all essential variables shall be recorded for each pass as part of the welding procedure qualification, and the data records shall be submitted with the qualifications for COMPANY review and approval.

11. Weld-through primers, where used during fabrication, shall be included in the welding PQR in

accordance with Section 7.5.2.

12. COMPANY shall witness all new weld procedure qualification tests. A schedule of procedure

qualification testing shall be provided to COMPANY.

13. Where previously qualified WPS and PQR are submitted for approval, adequate documentation of

the results from an independent testing laboratory shall be included.

14. Combinations of welding processes shall not be used unless qualified in accordance with AWS D1.1/D1.1M:2020, Section 6 (for plate structures) and Section 10 Part C (for tubular structures), “WPS Qualification” and the following conditions are met:

a) The welding process has been explicitly stated for each kind of passes (root, hot, fill, cap, back

pass) (e.g., optional passes are not permitted).

b) The combination of welding processes has been fully tested with supporting PQR

documentation.

c) CVN testing shall be performed on each welding process in the weld joint.

d) A single welding process PQR shall not be combined with another PQR to support a combination

process WPS unless such welding processes have been qualified in combination.

e) A combination welding process PQR shall not be used to support a single welding process WPS.

f) A combination welding process WPS shall be qualified by one or more PQR that each includes

the same combination of welding processes.

15. The back side of CJP groove welds shall be back-gouged by chipping, arc-air gouging following by grinding to sound metal before any welding is performed on the opposite side. The back-gouged groove detail shall be as specified by the applicable WPS. Any exemption to such requirement is subjected to prior COMPANY approval

16. CJP welds welded from one side shall be limited to ≤ 25 mm (1.0 in.) or when there is no appropriate safe access for back side welding. One-side welded CJP welds that are not back-gouged shall be qualified with ceramic backing material with the specific brand and configuration documented on the PQR and WPS.

17. In case one-side welded CJP welds with GTAW or SMAW process for root pass, ceramic backing

is not necessarily to be used.

Company No._Rev. 200-22-ST-SPC-00007_00

43 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

7.5.2 Weld-Through Primer Qualification Test

1. Weld-through primers, where used during fabrication, shall be included in the welding PQR. The primer trade name and the maximum applied thickness shall be considered to be essential variables. Supplementary testing shall comply with the Weld-Through Primer Qualification Test from Figure 7.1, with zero root gap. Primer shall be removed from all CJP welds.

2. The entire length of the fillet weld tests shall be examined visually. The weld shall present a reasonably uniform appearance and shall be free of overlap, cracks, and undercut in excess of the AWS D1.1/D1.1M, Ref. [64] requirements. There shall be no porosity visible on the weld surface.

3. A 150 mm (6 in.) long specimen shall be loaded in such a way that the root of the weld is in tension.

At least one welding stop/start shall be located within the test specimen.

4. The load shall be increased or repeated until the specimen fractures or bends flat upon itself.

5. The broken specimen shall be determined to be acceptable if the specimen bends flat upon itself, or if fractured, has a fracture surface showing complete fusion at the root of the joint with no inclusion or porosity larger than 2.5 mm (0.10 in.) in greatest dimension, and the sum of the greatest dimensions of all inclusions and porosity shall not exceed 10 mm (0.40 in.) in the 150 mm (6 in.) long specimen.

6. A macroetch specimen shall be prepared to demonstrate weld metal soundness. The PQR shall

include a photomacrograph of the macroetch specimen.

Figure 7.1: Weld-Through Primer Qualification Test

Company No._Rev. 200-22-ST-SPC-00007_00

44 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

7.5.3 Hardness Testing

1. Welding procedure qualifications shall include hardness testing of the HAZ, weld metal, and base

metal. Hardness testing shall be performed in accordance with ASTM E384, Ref. [52].

2. Hardness traverses shall be made within 1–2 mm (0.04–0.08 in.) from the ID and OD surfaces (see

Figure 5.2).

3. Hardness impressions in the weld metal and base metal shall be spaced 2 mm (0.08 in.) apart.

4. The first hardness impression in the HAZ shall be located 0.25–0.50 mm (0.01–0.02 in.) from the

fusion line and located entirely in the CGHAZ.

5. Subsequent impressions shall be located at 0.50–0.75 mm (0.02–0.03 in.) intervals along the

CGHAZ.

6. A minimum of three impressions shall be made in each area (weld metal, HAZ, and base metal on

each side) for each traverse.

7. Hardness values, greater than 325 Vickers using a 10 kg (22 lb) load, are not acceptable and shall

require a new PQR.

Figure 7.2: Sketch Showing Base Metal, Weld and Heat-Affected Zone of Typical Weld for

Guidance in Making Macro Hardness Traverses

Company No._Rev. 200-22-ST-SPC-00007_00

45 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

7.5.4 CVN Impact Testing

1. CVN impact testing of both weld metal and HAZ shall be required on all welding procedure

qualifications, except for welding NT materials.

2. CVN testing of both the weld and HAZ shall be in accordance with AWS D1.1/D1.1M Section 6, Ref.

[64], Part D “Requirements for CVN Toughness Testing.”

3. CVN test specimen location shall be in accordance with AWS D1.1/D1.1M, Ref. [64], Figure 6.28 “CVN Test Specimen Locations,” except that for thickness > 20 mm (0.75 in.), an additional WM centerline specimen shall be taken at the T/4 location B centerline.

7.5.5 CVN Impact Testing Acceptance Criteria

Acceptance criteria for both weld metal and HAZ specimens shall be in accordance with Table 7.2

Table 7.2: Acceptance Criteria for Weld Metal and HAZ Specimens

Yield Type/Toughness Class

Test Temp (4) (5)

Min. Average J (ft-lb) (5)

Min. Single Values J (ft-lb) (5)

I / NT

I / CV1

I / CV2, CV2Z4, CV2Z5, CV2X, CV2ZX

II / NT

II / CV1

II / CV2, CV2Z4, CV2Z5, CV2X, CV2ZX

III / NT

III / CV1

III / CV2, CV2Z4, CV2Z5, CV2X, CV2ZX

Notes:

(Note 1)

21 (15) (1)

17 (12) (1)

LAST 20oC (54o F) below LAST (Note 2)

LAST 20oC (54o F) below LAST (Note 3)

27 (20)

27 (20) 42 (30) (2)

42 (30)

42 (30) 47 (35) (3)

LAST 20oC (54o F) below LAST

47 (35)

47 (35)

20 (15)

20 (15) 35 (25) (2)

35 (25)

35 (25) 40 (30) (3)

40 (30)

40 (30)

(1) Electrodes for Yield Type/Toughness Class I/NT shall meet or exceed AWS requirements for a

minimum of 21/17 J at 0C (15/12 ft-lbs at 32F). PQR Charpy testing is not required.

(2) Electrodes for Yield Type/Toughness Class II/NT shall meet or exceed AWS requirements for a

minimum of 42/35 J at 0C (30/25 ft-lbs at 32F). PQR Charpy testing is not required.

(3) Electrodes for Yield Type/Toughness Class III/NT shall meet AWS requirements for a minimum of

47/40 J at 0C (35/30 ft-lbs at 32F). PQR Charpy testing is not required.

(4) The Charpy test temperature shall be as defined in this table or the minimum designed Charpy

test temperature as per structural material specification of the material to be welded, whichever is lower.

(5) Weld Metal Charpy Test temperature & Acceptance Criteria in case of different Yield Type and/or Toughness class shall meet most stringent of both (i.e.: Lower Test Temperature and Higher Energy Values requirements). HAZ Test Temperature & Acceptance criteria requirements shall be according to each side (i.e., HAZ side A & HAZ side B) applicable Yield Type & Toughness Class.

Company No._Rev. 200-22-ST-SPC-00007_00

46 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

7.5.6 Additional Essential Variable Requirements for Thickness Ranges

AWS D1.1/D1.1M, Ref. [64] limits on qualified thickness ranges shall be followed, except for the following additional requirements:

1. For PQRs where CTOD testing is required, the maximum thickness shall be limited to the thickness

of the CTOD test coupon.

2. For T-Y-K connections in pipe with wall thickness ≥ 25 mm (1.0 in.), a large-scale 6GR test shall be required. The test joint shall be similar to AWS D1.1/D1.1M, Ref. [64], Figure 10.20 “Test Joint for T-, Y-, and K-Connections without Backing on Pipe or Box Tubing—Welder and WPS Qualification,” except for the following changes:

a) Minimum outside diameter shall be 324 mm (12.75 in.)

b) Minimum wall thickness shall be 25 mm (1.0 in.)

c) Minimum length of each pipe nipple shall be 305 mm (12 in.)

7.5.7 Additional Essential Variables for CV2, CV2Z4, CV2Z5, CV2X, CV2ZX

The following additional essential variables shall apply to Toughness Class CV2, CV2Z4, CV2Z5, CV2X, and CV2ZX welding procedures qualifications:

1. An increase in the CE > 0.03 versus the base material used for the procedure qualification.

2. A change in the process of manufacture for the base material, according to the following groups:

a) Quenched and tempered steels.

b) TMCP or controlled rolled steels.

c) Normalized or as-rolled steels.

3. An increase of more than 30ºC (54ºF) over the maximum interpass temperature attained on the

procedure qualification.

4. A change greater than ± 25 percent in the heat input of any welding pass from the average value

calculated for the procedure qualification test for each process.

5. Heat inputs for fill passes and cap passes shall be grouped separately in determining the average heat input qualified, and the minimum heat input for the cap pass shall not be less than the lowest heat input pass adjacent to base metal on the procedure qualification.

6. Any change in the electrode or electrode/flux brand name or Manufacturer.

7. For the FCAW process, the maximum bead width and layer thickness shall not be greater than that

qualified during PQR testing.

7.5.8 CTOD Requirements for CV2X and CV2ZX

1. CTOD testing of weld metal shall be required for all welding procedure qualifications on Toughness

Class CV2X and/or CV2ZX steels weld to CV2X or CV2ZX.

2. Weld metal CTOD testing shall be performed on the thickest steel to be welded for each steel type, using the highest preheat, heat input, and interpass temperature permitted by the welding procedure to be qualified.

3. Specimens shall be tested in the as-welded condition, with the notch located at the centerline of the weld. Surface notched geometry specimens on weld repair centerline shall be used for repair weld tests, unless the repair weld consumable has been qualified by CTOD testing of a full penetration butt weld made using the same welding parameters.

Company No._Rev. 200-22-ST-SPC-00007_00

47 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

4. CTOD tests shall be performed in accordance with BSI BS EN ISO 15653, Ref. [66], ASTM E 1290,

Ref. [54], or an equivalent standard approved by COMPANY.

5. A minimum of three valid CTOD test results shall be obtained.

6. Test temperature shall be at LAST = 0ºC.

7. CTOD acceptance criteria shall be 0.25 mm (0.010 in.) for thicknesses ≤ 75 mm (3.0 in.), and 0.38

mm (0.015 in.) for thicknesses > 75 mm (3.0 in.).

7.5.8.1 Additional Essential Variables for CTOD Testing

1. The following additional essential variables shall apply to all WPS where CTOD testing of Toughness Class CV2X and CV2ZX weld metal is required as part of the PQR. These are in addition to the essential variables listed in Section 7.5.7 of this Project Specification and AWS D1.1/D1.1M, Ref. [64]:

a) Any increase in thickness of the base material versus that used for the PQR.

b) Any increase in the maximum preheat, heat input, or interpass temperature versus the

PQR.

c) Any reduction in the depth or width of back-gouging versus that used for the PQR.

d) Any change in the type of power supply (constant voltage or constant current) or wire feeder (constant feed or voltage sensing) for flux-cored arc welding (FCAW-SS or FCAW-GS) only.

e) A change in filler metal and/or flux brand, brand name, or location of manufacture.

2. For all welding on Toughness Class CV2X and CV2ZX steels, preheat, heat input, and interpass temperature shall be within the prequalified ranges in accordance with API RP 2Z, Ref. [36] (min. = 0.8 kJ/mm, max. = 4.5 kJ/mm). If BS EN 10225 Option 17, Ref. [69], materials are approved for procurement, the additional limitation on heat input range shall be within that qualified through Option 17.

7.6 Welding Equipment

7.6.1 Condition of Equipment

1. Welding machines, line-up clamps, beveling machines, cutting torches, tools, supplies, and other equipment used in conjunction with the welding work shall be kept in good mechanical condition to ensure production of sound welds.

2. Welding machines shall have adequate controls for making the current adjustments necessary for all welding requirements. Sufficient meters, portable or permanent shall be provided to calibrate machines and to regulate voltage and amperage as needed.

3. Welding equipment for the FCAW-SS process shall require COMPANY approval. Current COMPANY-approved equipment (wire feeder and constant voltage DC power source) is supplied by Lincoln or Miller.

7.6.2 Grounding of Equipment

Grounding of welding machines shall be in accordance with API RP 2A-WSD, Ref. [35] and with the following additional requirements:

1. Each welding machine shall be individually grounded to the platform or portion of the platform being

welded.

2. Ground clamps for pipe shall be designed to prevent arcing.

Company No._Rev. 200-22-ST-SPC-00007_00

48 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

3. CONTRACTOR shall develop a Stray Current Control Procedure for COMPANY review and

approval.

7.7 Preheat and Interpass Temperatures

1. Welding preheat and interpass temperatures shall be as specified in CONTRACTOR’s qualified WPS, but shall be in accordance with AWS D1.1/D1.1M, Ref. [64], Table 5.8 “Prequalified Minimum Preheat and Interpass Temperature.”

2. The alternative methods for determining preheat given in AWS D1.1/D1.1M, Ref. [64], Annex B “Guideline on Alternative Methods for Determining Preheat” may be used with written COMPANY approval.

3. For any metal that is damp or less than 10ºC (50°F), a minimum preheat of 65ºC (150°F) shall be

required regardless of thickness.

4. Regardless of the AWS recommended temperature or method used to determine preheat, the

preheat specified and applied shall be sufficient to prevent hydrogen cold cracking.

5. Preheat shall be performed by using oxy-fuel bulbous type torches, induction, or electric resistance

heat.

6. When the thickness of any member is greater than 65 mm (2.25 in.), electric resistance preheat

shall be used. Other alternative method is subjected to COMPANY approval

7. Preheat and preheat monitoring shall be in accordance with a written CONTRACTOR procedure

submitted to COMPANY for review and approval.

8. Maximum interpass temperatures shall not exceed the limit established by the PQR.

7.8 Welder and Welder Operator Qualifications

1. CONTRACTOR shall qualify all Welders and Welding Operators to be used for fabrication.

2. All Welders and Welding Operators shall be qualified in accordance with AWS D1.1/D1.1M, Ref.

[64], Section 6 Part C and Section 10 Part D, “Performance Qualification”.

3. Production CJP, T-K-Y box tubing welds shall include appropriate qualification using box tubing.

4. COMPANY shall be notified of all Welder and Welding Operator qualification testing to be performed

and have the option to witness all qualifications.

7.8.1 Testing

1. Welders and Welding Operators shall be qualified by destructive testing.

2. Radiography may be performed in addition to destructive testing; however, qualification by

radiography alone shall not be accepted.

3. If radiographic testing is performed, radiographs shall be made available for COMPANY review.

4. Records of the results of all qualifying tests shall be maintained by CONTRACTOR and submitted

to COMPANY upon request.

7.8.2 Previous Qualification

1. Records of previously qualified welders may be submitted to COMPANY for review and approval in lieu of new qualifications and may be accepted if requirements of this Project Specification are met.

7.8.3 Failure to Qualify

1. Any Welder who fails to qualify shall not be permitted to retest without COMPANY approval.

Company No._Rev. 200-22-ST-SPC-00007_00

49 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

2. CONTRACTOR shall remove immediately from the project any Welder who, in the opinion of COMPANY, is not careful, not skilled, or incompetent or negligent in the proper performance of his or her duties.

7.8.4 Additional Essential Variables

In addition to AWS D1.1/D1.1M, Ref. [64] essential variables for Welder and Welding Operator performance qualification, the following shall apply:

1. For FCAW, a change from self-shielded to gas-shielded, or vice versa, shall require a new

qualification.

2. For GMAW, a change in the mode of metal transfer from short-arc to any other mode (globular,

spray, or pulsed) shall require a new qualification.

3. An increase in the specified minimum tensile strength of the filler metal shall require a new

qualification.

7.9 Weld and Welder Identification and Marking

1. Prior to fabrication, CONTRACTOR shall establish a comprehensive numbering system that

provides unique identification of each weld and each qualified Welder.

2. The numbering system shall be used for identification purposes at each weld, on all shop drawings,

and for indexing all NDT inspection reports and repairs.

3. Prior to commencement of fabrication, CONTRACTOR shall supply COMPANY with details of the

identification system, including subsequent revisions or modifications.

4. Low stress die stamps shall be used for weld and Welder identification. However, a paint stick may

be used with written COMPANY approval.

7.10 Workmanship

Workmanship shall comply with the requirements in the following subsections.

7.10.1 General

Permanent backing rings, bars, or plates shall not be permitted, except as indicated below:

1. Backing rings shall be allowed only on structural tubular braces less than DN 600 (NPS 24) and

shall be qualified and used in accordance with COMPANY-approved welding procedures.

2. For gas-shielded processes (FCAW-GS, GTAW, and GMAW), the wind speed adjacent to the arc shall be a maximum of 8 km/hr (5 mph) to allow adequate gas coverage of the molten puddle. For all outside welding, suitable windshields shall be furnished to limit wind speed adjacent to the arc.

7.10.2 Forming

1. A Cold Forming Procedure shall be submitted to COMPANY for review and approval prior to

production fabrication.

2. A Hot Forming Procedure shall be submitted to COMPANY for review and approval prior to

production fabrication.

3. All forming procedures shall be qualified on the specific type of steel to be formed (i.e., yield type and toughness class). Cold forming procedures with strains corresponding to less than 5 percent extreme fiber elongation do not require qualification testing. The extreme fiber elongation shall be calculated in accordance with Equation 1, or COMPANY-approved equivalent formula called out by the forming procedure.

Company No._Rev. 200-22-ST-SPC-00007_00

50 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

Equation 1: Percent Extreme Fibre Elongation

For single curvature (e.g., cylinders)

For double curvature (e.g., heads)

Where:

t = plate thickness, mm (in) Rf = final centre line radius, mm (in) Ro = original centre line radius (equals infinity for flat plate), mm (in)

4. Qualification shall consist of application of the highest extreme fiber elongation, at the highest recommended forming temperature, to the thickest material to be qualified, and then repeating all mechanical testing required by the material specification, in accordance with the forming procedure.

5. Mechanical test results after forming shall meet the minimum requirements of the material

specification, including any supplementary or COMPANY-imposed requirements.

7.10.3 Preparation and Fit-Up

1. During welding, the weld joint and adjacent base metal shall be kept free of moisture, grease, loose

mill scale, rust, and paint.

2. Surfaces showing carbon deposits or slag due to arc-gouging or oxy-fuel cutting shall be cleaned

by sand blasting or grinding to remove carbon residue and slag.

3. Any deviation from the WPS (e.g., weld gaps, inadequate preheat) shall be rectified before welding

commences.

4. Weld fit-up shall be within tolerances specified in AWS D1.1/D1.1M, Ref. [64] or an equivalent

standard approved by COMPANY.

7.10.4 Surface Considerations

1. Surfaces of metal to be welded shall be free of fins, tears, cracks, loose scale, slag, rust, oil, paint,

and other defects that would adversely affect the quality or strength of the weld.

2. When more than one weld pass is deposited on a joint, each pass shall be thoroughly cleaned by

wire brushing and chipping as necessary before the next pass is applied.

7.10.5 Distortions

1. Welding shall proceed in a manner that minimizes residual stresses or distortions.

The finished structure shall be as free from distortion as possible.

2. CONTRACTOR shall be responsible for preventing or correcting distortion, and for maintaining alignment within a specified tolerance, by COMPANY-approved procedures such as use of strong backs. COMPANY shall be the judge of these factors and shall have the right to delay the work if excessive distortion becomes evident, until such time as corrective methods may be successfully applied.

Company No._Rev. 200-22-ST-SPC-00007_00

51 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

3. CJP groove welds on material over 25 mm (1.0 in.) thickness shall be double bevel or double-vee

welds unless there is no sufficient access for welding on second side or it is unsafe.

4. Splices in DN 600 (NPS 24) and larger pipe members shall be full-penetration, double-sided butt joints, welded and inspected from both the inside and outside of the pipe. Single-sided splices require COMPANY approval. Confined space entry procedures shall be followed in all instances of pipe entry.

7.10.6 Cooling

1. Welds shall not be quenched or cooled other than by contact with the natural atmosphere.

2. Welds shall be protected from rapid cooling caused by rain, wind, or inclement weather. COMPANY shall determine whether adequate weather protection has been provided for welding to continue.

7.10.7 Weld Run-off Tabs and Access Holes

1. Weld run-off tabs shall be used prior to welding where practicable (e.g., beam flanges, long seams

on pipe, etc.).

2. Access holes for welding shall be shown on detail drawings and shall not exceed specified size. All

access holes shall be sealed by one of the following methods:

a) Completely seal welding by returning fillet welds through the opening.

b) Covering both sides with 6 mm (¼ in.) plate, fully seal welded.

7.10.8 Arc Strikes and Temporary Weldments

1. COMPANY may require CONTRACTOR to remove any Welder who continually arc-burns the

material.

2. CONTRACTOR shall develop an arc strike removal procedure that shall be submitted to COMPANY

for review and approval.

3. Arc strikes not covered by subsequent weld passes shall be ground out, repaired, and MT inspected

in accordance with a COMPANY-approved arc strike removal procedure.

4. After temporary attachments are removed, the welded areas shall be ground smooth, and MT inspected. Temporary attachments shall be cut to no less than 3 mm (0.12 in.) above the parent material and mechanically ground flush.

7.10.9 Cleaning and Repairing of the Ends of Pipes, Plates, and Shapes

1. Minor dents at the ends of pipe, plates, and shapes, may be straightened with a jack or properly

applied impact bronze-faced sledgehammer or flatter.

2. When weld-through primers are used, the weld bevel and adjacent area shall be thoroughly cleaned (by grit blasting, grinding, power buffing or COMPANY-approved equal) prior to primer application.

7.10.10 Flame Straightening

1. A Flame Straightening Procedure shall be submitted to COMPANY for review and approval prior to

the start of fabrication.

2. Flame straightening temperatures shall not exceed 500ºC (932ºF). The method of measuring and

controlling the temperature shall be stated in the flame straightening procedure.

3. Flame straightening procedure qualifications shall be performed to demonstrate that the straightening procedure does not have any detrimental effects on the base materials being straightened or heated.

Company No._Rev. 200-22-ST-SPC-00007_00

52 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

7.11 Safety

Safety shall be in accordance with contractual documents and meet all national, state, and local requirements where applicable.

Company No._Rev. 200-22-ST-SPC-00007_00

53 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

8 CONTRACTOR REQUIREMENTS

1. CONTRACTOR shall perform the work for COMPANY.

2. All welding and inspection shall be in accordance with this Project Specification and referenced

specifications, codes, and standards.

3. At all times during the performance of the work, CONTRACTOR shall keep a competent

Superintendent and/or Foreman on the job site.

4. Any written or verbal instructions given to such Superintendent or Foreman by COMPANY shall be

construed as having been given to CONTRACTOR.

Company No._Rev. 200-22-ST-SPC-00007_00

54 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

9 QUALITY ASSURANCE REQUIREMENTS

1. CONTRACTOR shall comply with all requirements of Project Specification.

2. This QAP shall be available for COMPANY review upon request.

9.1 Quality Control

1. As a minimum, quality control procedures for the following elements shall be submitted for

COMPANY review and approval:

a) Control of materials, including receipt, storage, and issue

b) Product identification and traceability (may be combined with NDT Plan)

c) Inspection and Test Plans

d) Calibration of inspection and test equipment

e) Weld summary sheet identifying where all WPS shall be used

f) Fabrication Procedures (e.g., identifies alignment, fit-up, heat treatment, etc. requirements)

g) Preheat and Preheat Monitoring Procedure

h) Consumable Storage and Handling Procedure with Manufacturer’s Recommendations for all

Consumables

i) Cold Forming Procedure (as required)

j) Hot Forming Procedure (as required)

k) Flame Straightening Procedure

l) Weld Repair Protocol - Protocol for Minor and Major Repairs

m) Major Weld Repair Procedures (as required)

n) Wide gap welding procedures (as required)

o) Stray Current Control Procedure

p) Preservation of materials and equipment

q) Qualification of Welding Inspection personnel, and Welders

r) Control of special processes

s) Dimension control

t) Equipment installation

u) Maintenance and traceability of inspection and test records

v) Surface treatment and painting inspection

w) Data dossier contents, compilation, and handover (TCP)

x) Reject rate reporting for production welding and Welder performance

y) In-process inspection, including joint type and preparation, fit-up, tack welding, welding monitoring (Heat Input Monitoring, Wire Feed Speed, Travel Speed, Electrical Parameters, preheat & interpass temperature), back-gouging, and final weld inspection

z) PWHT monitoring (where applicable)

Company No._Rev. 200-22-ST-SPC-00007_00

55 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

aa) NDT Plan, which shall also reflect timing of NDT application on completed welds, and technician

qualifications

2. CONTRACTOR shall provide additional procedures for the proper control of work quality when

COMPANY deems necessary.

Company No._Rev. 200-22-ST-SPC-00007_00

56 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

10 NON-DESTRUCTIVE TESTING (NDT)

10.1 General

1. All NDT shall be in accordance with the requirements of APPENDIX 1 & 2 of this Project

Specification.

2. COMPANY shall have the right to require supplementary NDT or increased inspection percentages

to assist the evaluation of weld defects.

3. NDT methods, acceptance criteria, and operator qualifications shall be in accordance with Table

10.1 and Table 10.2.

4. Contractor shall submit all NDT procedures to COMPANY for review and approval.

5. COMPANY and CONTRACTOR shall agree upon hold/release/witness points prior to assembly,

welding, NDT, and painting of individual components.

6. Inspection at fit-up, prior to first pass, shall be both visual and dimensional.

7. Inspection following back-gouging shall be visual only unless one or more NDT techniques are required to explore the extent of visually observed flaws or unless previous production performance indicates that unacceptable flaws may be present.

8. With the exception of the API Certified, API SPEC 2B, Ref. [37] pipe mill welds, all welds shall be

non-destructively tested no sooner than 48 hours after welding.

9. Higher preheat temperature or performing a hydrogen bakeout procedure after welding shall be

done when exceptions to the 48-hour criteria are granted.

10. CONTRACTOR shall submit individual 48-hour exceptions, the reason for minimizing delay, and the proposed preheat procedure to COMPANY. COMPANY approval shall be obtained before the subject weld is performed.

11. COMPANY reserves the right to test any welding samples as necessary to verify quality of work.

10.2 NDT Plan

1. CONTRACTOR shall prepare an NDT plan for all NDT and testing to be performed and shall submit

the plan to COMPANY for approval prior to fabrication.

2. The NDT plan shall be auditable and include the following:

a) Material traceability (as applicable)

b) Weld mapping—capable of tracking and identifying weld, Welder, weld rejects (R1, R2, etc.),

and Welder reject rates.

c) NDT mapping and timing of NDT—VT, RT, UT, PT, MT (as applicable)

d) PWHT mapping (as applicable)

e) Hydrotest mapping (as applicable)

f) Qualification and testing of NDT procedures

g) Qualification and certification of NDT technicians and personnel

10.3 Personnel Qualifications

1. CONTRACTOR’s Lead Structural Welding Inspector for the Project shall be certified by the

American Welding Society as a CWI or a COMPANY-approved equivalent certification.

Company No._Rev. 200-22-ST-SPC-00007_00

57 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

2. COMPANY shall review and approve any NDT testing company utilized by CONTRACTOR for

fabrication under this Project Specification.

3. NDT personnel shall be qualified in accordance with ASNT SNT-TC-1A, Ref. [45] or equivalent

standard approved by COMPANY.

4. NDT personnel can also be qualified under ISO 9712, Ref. [74].

5. NDT personnel shall have the qualifications required by Table 10.1 and Table 10.2 and shall be

subject to COMPANY approval.

6. COMPANY reserves the right to reject for cause and demand a re-qualification test for any and all

NDT personnel at any time.

7. CONTRACTOR shall furnish all necessary labor and equipment for the transportation and

preparation of pipe, plate, and other materials for testing.

8. CONTRACTOR shall submit, as part of the NDT Plan, all current and updated NDT certifications to

COMPANY for review.

10.4 Visual Inspection (VT)

1. All welds shall be VT inspected and shall meet the requirements of AWS D1.1/D1.1M, Ref. [64],

Table 6.1 “Visual Inspection Acceptance Criteria.”

2. Visual and dimensional inspections shall be performed at weld joint fit-up prior to the first pass.

3. Weld profiles, including tubular connections, shall conform to the requirements of AWS D1.1/D1.1M,

Ref. [64], Section 5, Paragraph 5.23, “Weld Profiles.”

4. All primary steel welds in the assembly and erection areas shall be visually inspected at each of the

stages listed in the ITP.

5. Inspection for laps, seams, fins, and laminations after blasting and/or priming shall be VT inspected.

6. In the case of overlapping welds, the initial weld shall be inspected by all required NDT methods as

per NDT extent, prior to completion of any further welds.

10.5 Radiographic Testing (RT)

1. CONTRACTOR shall submit the RT procedure to COMPANY for review and approval.

2. The RT procedure shall be in accordance with Table 10.1 and Table 10.2.

3. The RT acceptance criteria shall be in accordance with Table 10.1 and Table 10.2.

4. Cutting of holes for insertion of radiographic or x-ray sources shall not be performed without

COMPANY approval.

5. UT may be used to supplement RT, when approved by COMPANY on a case-by-case basis.

10.6 Ultrasonic Testing (UT)

1. CONTRACTOR shall submit the UT procedure to COMPANY for review and approval.

2. The UT procedure shall be in accordance with Table 10.1 and Table 10.2.

3. The UT acceptance criteria shall be in accordance with Table 10.1 and Table 10.2.

4. If defects revealed by RT are difficult to evaluate, then UT shall be used to facilitate interpretation,

or vice versa.

Company No._Rev. 200-22-ST-SPC-00007_00

58 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

10.7 Magnetic Particle Testing (MT)

1. CONTRACTOR shall submit the MT procedure to COMPANY for review and approval.

2. The MT procedure shall be in accordance with Table 10.1 and Table 10.2.

3. The MT acceptance criteria shall be in accordance with Table 10.1 and Table 10.2.

4. MT inspection shall be performed using the wet method AC yokes with contrasting background

paint.

10.8 Penetrant Testing (PT)

1. CONTRACTOR shall submit the PT procedure to COMPANY for review and approval.

2. PT procedure shall be in accordance with Table 10.1 and Table 10.2.

3. PT acceptance criteria shall be in accordance with Table 10.1 and Table 10.2.

4. PT procedure shall only be used for weldments that are specifically approved by COMPANY.

10.9 Contractor Inspection Responsibility

1. CONTRACTOR shall inspect all work during fabrication.

2. CONTRACTOR shall conduct inspections sufficient to ensure that materials, fabrication, and testing

comply in all respects with the requirements of this Project Specification.

3. Inspections by COMPANY shall not relieve CONTRACTOR from the duty to implement any quality assurance procedures necessary to ensure that the requirements and intent of this Project Specification are satisfied.

4. Before construction begins, COMPANY shall notify CONTRACTOR of the stages of fabrication at

which special examinations shall be made.

5. CONTRACTOR shall give at least 24 hours notice to COMPANY before each stage is reached.

6. COMPANY shall have the right to examine work at any stage, and to reject defective material or

workmanship whenever found.

7. CONTRACTOR shall provide COMPANY access to the fabrication facility at all times during work in progress, and COMPANY shall be at liberty to inspect the fabrication at any stage and to reject any part not complying with this Project Specification.

8. When, in the opinion of COMPANY, any section requires inspection, CONTRACTOR shall thoroughly clean the section of all excess and waste materials (such as sand, slag, or welding electrodes) and allow sufficient time for the section to be properly inspected.

9. CONTRACTOR shall have copies of the latest edition of the Specifications and Codes referred to in this Project Specification and make them readily available to inspection personnel involved in the project.

10. CONTRACTOR shall furnish, install, and maintain in a safe operating condition any scaffolding,

ladders, walkways, and lighting necessary for safe and thorough inspection by COMPANY.

11. All inspections shall be conducted before proceeding with the assembly sequence. In the event that inspections are missed, CONTRACTOR shall perform whatever disassembly is required to safely perform the necessary inspections and reinstall lighting, scaffolding, and safe access to all locations requiring such inspections.

Company No._Rev. 200-22-ST-SPC-00007_00

59 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

Table 10.1: Weld Acceptance Criteria and NDT Qualifications

NDE Method

Inspection Procedure

Acceptance Criteria

Minimum NDT Operator (2) (4) Qualification

VT

AWS D1.1/D1.1M:2020

AWS D1.1/D1.1M:2020 Table 8.1 / 10.15

AWS Certified Welding Inspector (CWI) (3)

API RP 2X

API RP 2X, Level C (5, 6)

ASNT Level II and tested per API RP 2X

UT

RT

AWS D1.1/D1.1M:2020 Section 8, Part E

MT

ASTM E 709

PT (1)

ASTM E 165

AWS D1.1/D1.1M:2020, see table 4b of this document

AWS D1.1/D1.1M:2020, see table 4b of this document

AWS D1.1/D1.1M:2020, see table 4b of this document

ASNT Level II

ASNT Level II

ASNT Level II

Notes:

(1) When approved by COMPANY.

(2) Or equivalent certification approved by COMPANY.

(3) Qualified in accordance with AWS D1.1/D1.1M:2020 or COMPANY approved equivalent certification

(4) CONTRACTOR shall submit currently updated NDT Operator certifications to COMPANY for review.

(5) Padeye and lifting eye acceptance criteria API RP 2X Level “A.”

(6) When UT is used as an alternate to RT, AWS D1.1 Class R criteria shall be used (as per 10.26.1.1 of AWS

D1.1:2020)

Table 10.2: NDT Acceptance Criteria for Each Type of Load

AWS D1.1

Load

Item

RT

MT

PT

Edition 2020

Statically

Cyclically

Non-tubular

Tubular

Non-tubular

Tubular

Sec. 8.12.1 & Figure 8.1

Sec. 8.12.1 & Figure 8.1

Sec. 8.12.2 & Figure 8.2 & 8.3

Sec. 8.12.1 & Figure 8.1

Table 8.1

Table 8.1

Table 10.15

Table 10.15

Table 8.1

Table 8.1

Table 10.15

Table 10.15

Company No._Rev. 200-22-ST-SPC-00007_00

60 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

11 WELDING REPAIRS

11.1 General

1. CONTRACTOR shall repair or replace all welds made by CONTRACTOR that do not meet the requirements of this Project Specification, AFC drawing requirements, and/or the applicable codes and standards.

2. A weld repair protocol shall be submitted and approved by COMPANY prior to making any repairs. The weld repair protocol shall include a description of both minor and major repairs, and describe the means by which COMPANY notification, prior approval, and record keeping of all major repairs shall be obtained. Minor repairs may be performed without COMPANY notification, in accordance with the approved weld repair protocol.

3. Minor Repairs of surface and weld defects, as defined in Table 11.1, by chipping, grinding, and gouging shall be permitted, provided that the thickness is not reduced below the minimum required. Where necessary, minor repair welding shall be performed by qualified Welders using a COMPANY- approved WPS.

4. Major Repairs in weldments, base materials, castings, etc., as defined in Table 11.1, shall not be

repaired until a written procedure for each individual repair has been approved by Company.

5. No cracks shall be removed or repaired by CONTRACTOR without prior approval of CONTRACTOR’s repair procedure. COMPANY shall be notified of all cracking issues. All cracks shall be repaired in accordance with an approved weld repair procedure.

6. All weld repair procedures shall require an additional 30°C (54°F) increase in the preheat

temperature than that required for the original weld.

7. Excavation of defects shall be verified by MT, as a minimum.

8. All repairs involving a primary member shall require a weld repair PQR when more than one repair attempt is required (e.g., R2, R3, etc.), as detailed in Section 11.2. CONTRACTOR shall be responsible for testing the repaired portion of the weld.

9. A maximum of one repair attempt is permitted for weld joints involving a primary member, without a weld repair PQR. Subsequent repair attempts are considered to be major repairs, regardless of cause or dimensions, and require a weld repair PQR.

10. Prior to qualification of a weld repair WPS, a pWPS shall be submitted to COMPANY for review and

approval.

11. Weld repairs shall be made using the WPS that was originally used for the weld joint. If the repair WPS is a change of process or a different WPS from the original WPS used for the weld joint, then a weld repair PQR shall be qualified in accordance with Section 11.2.

12. For repairs made to welds originally made by the FCAW-SS process where the repair is made using a different welding process (e.g., SMAW), a weld repair PQR shall be qualified in accordance with Section 11.2 for the combination of weld metal. This repair procedure shall be qualified in the 3G position, and the qualification shall include CVN impact testing. The CVN impact testing shall locate the V notches at:

a) The highest dilution zone of the original weld by the repair weld.

b) Immediately below the fusion line within the FCAW-SS weld.

13. If COMPANY considers the proposed repair of a defect to be either non-productive or detrimental to the completed facility, CONTRACTOR shall not repair the defect but cut out the weld and redo the work.

Company No._Rev. 200-22-ST-SPC-00007_00

61 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

11.2 Weld Repair WPS Qualification

1. Where required by Section 11.1, a WPS for weld repair shall be qualified in accordance with Section

7.5 and the additional requirements of this Section.

2. COMPANY shall witness all welding and NDT of the weld repair qualification.

3. All weld repair procedures shall require a 30ºC (54ºF) increase in the preheat temperature than that

required for the original weld.

4. Repair weld qualification shall be performed in accordance with Figure 11.1.

5. Repair weld qualification CVN locations shall be performed in accordance with Figure 11.2.

Figure 11.1: Weld Repair WPS Qualification

Figure 11.2: Weld Repair WPS CVN Qualification

Company No._Rev. 200-22-ST-SPC-00007_00

62 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

11.3 Types of Weld Repairs

11.3.1 General

1. Weld repairs shall be classified as major repairs and minor repairs.

2. Major and minor repairs are defined in Table 11.1.

11.3.2 Major Repairs

1. Major repairs in weldments, base materials, castings, etc. shall not be repaired until a written

procedure is developed for each individual repair.

2. Major repairs require specific case-by-case approval.

3. The written procedure shall be submitted to COMPANY for review and approval.

4. The written procedure shall include, but not be limited to, the following:

a) Root cause analysis for each defect

b) Identification as to primary, secondary, and tertiary member being repaired

c) Repair map or dimensioned sketch detailing the extent and location

d) Methodology used for defect removal (e.g., grinding, gouging, etc.)

e) NDT used to verify removal

f) COMPANY-approved WPS to be used

g) Heat treatment (as applicable)

h) NDT of final weld repair area

5. The root cause analysis shall consider the following areas when developing this portion of the written

procedure:

a) Data Collection:

i) Conditions existing during welding

ii) Personnel involved

iii) Environmental factors

iv) Any other information relevant to the repair area or component

b) Assessment:

i)

Identifying the problem

ii) Significance of the problem

iii) Identifying the causes leading up to and surrounding the problem

iv) Identifying the reasons why the causes existed

c) Corrective Action:

i)

Identifying the correction action for each occurrence

ii)

ii)

Identifying if the corrective action will prevent reoccurrence

iii) Identifying if the corrective action is feasible

d) Inform: Discussing with and explaining to COMPANY the results of the analysis, including

corrective action.

Company No._Rev. 200-22-ST-SPC-00007_00

63 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

e) Follow-up: Identifying the methodology that will be followed to determine the effectiveness of the

corrective actions taken.

Table 11.1: Major/Minor Repairs

Base Metal

Weld Metal

No.

Defect Type

Minor Repair

Major Repair

Minor Repair

Major Repair

Crack

YES

Only if Crater cracks

YES (Except crater cracks)

Repair Cavity (based on area)

Repair Cavity (based on thickness)

≤ 65 cm2 or 10 in.2

65 cm2 or 10 in.2

≤ 65 cm2 / 10 in.2

65 cm2 / 10 in.2

≤ 50% Thk

50% Thk

≤ 50% Thk

50% Thk

Edge Defect (based on thickness)

≤ 25 mm deep, or T, whichever is less

25 mm deep, or T, whichever is less

Edge Defect (based on length)

Lack of Fusion

Lack of Penetration

Porosity

Slag Inclusion

10

Undercut

11

Arc Strikes

12

Repair after 1st attempt

13

Weld build-up or buttering

11.4 Gaps and Buttering

≤ 20% of edge length

20% of edge length

root gap ≤ 20 mm

root gap > 20 mm

YES

YES

YES

YES

YES

YES

(see item 2 and 3)

(see item 2 and 3)

YES (Only if involving primary member)

1

2

3

4

5

6

7

8

9

1. Where required, CONTRACTOR shall include a WPS for repair of wide gaps, as part of WPS

qualifications. A wide gap is considered as a root opening until max 25 mm (1.0 in.).

2. Wide gaps shall not be welded until a written procedure is developed for each individual wide gap

weld.

3. Wide gap welding requires specific case-by-case approval.

4. The written procedure shall be submitted to COMPANY for review and approval.

5. The written procedure shall include, but not be limited to, the following:

a) Identification as to primary, secondary, and tertiary member

b) Dimensioned sketch detailing the magnitude of the gap, extent, and location

c) COMPANY-approved WPS to be used

d) NDT of final weld area

Company No._Rev. 200-22-ST-SPC-00007_00

64 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

6. The wide gap WPS may include breaking the joint apart and buttering one or more members, in-situ buttering of one or more members, or welding onto backing material, as qualified by CONTRACTOR. Any backing material shall be removed prior to second side welding.

7. All wide gap WPS shall be qualified in accordance with Section 7.5 of this Project Specification and

the additional requirements of this Section.

8. The maximum allowable root opening for wide gap welding shall be 25 mm (1.0 in.).

9. All joints with root openings > 25 mm (1.0 in.) shall be refitted to bring the root opening within the tolerances indicated on the WPS or base material replaced in order to maintain welding tolerances.

10. A wide gap WPS shall be qualified on the thinnest material and the thickest material to be used

during fabrication.

11. All buttered ends for wide gap welds shall be inspected by MT and shall be included in the final

inspection of completed welds.

12. No buttering shall be allowed on square cut edges. All buttering shall be done on base materials

that have weld joint preparations.

13. Wide gap WPS qualification shall be in accordance with Figure 11.3.

14. Wide gap WPS qualification CVN locations shall be performed in accordance with Figure 11.4.

Figure 11.3: Wide Gap WPS Qualification (Typical)

Company No._Rev. 200-22-ST-SPC-00007_00

65 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

Figure 11.4: Wide Gap WPS CVN Locations (typical)

Company No._Rev. 200-22-ST-SPC-00007_00

66 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

12 MAJOR DELIVERABLES

Table 12.1 identifies the documents that shall be submitted to COMPANY for review and approval with the dates required for their submittal. These deliverables are also applicable to SUBCONTRACTORS.

Table 12.1: Schedule of Deliverables Prior to Start of Fabrication

CONTRACTOR Deliverable

Date Required

CONTRACTOR shall prepare and submit a complete set of WPS with supporting PQR for review and approval by COMPANY.

At least 30 working days prior to start of fabrication

CONTRACTOR shall prepare a weld register that identifies all WPS and the location in the structure where the procedures shall be used.

At least 30 working days prior to start of fabrication

The Consumable Storage and Handling procedure shall be submitted to COMPANY for approval prior to the start of fabrication.

At least 30 working days prior to start of fabrication

For any new WPS requiring qualification or WPS requiring re-qualification, a COMPANY approved testing laboratory shall perform mechanical tests.

Prior to weld testing

A schedule of procedure qualification testing shall be provided to COMPANY.

A Weld and Welder Identification and Marking System shall be provided to COMPANY.

At least 30 working days prior to start of fabrication

Prior to start of fabrication

A Cold Forming Procedure shall be established by CONTRACTOR and submitted to COMPANY for approval prior to production fabrication.

At least 30 working days prior to start of fabrication

A Hot Forming Procedure shall be established by CONTRACTOR and submitted to COMPANY for approval prior to production fabrication.

At least 30 working days prior to start of fabrication

A Flame Straightening procedure shall be established and qualified by CONTRACTOR and submitted to COMPANY for approval prior to production fabrication.

The QAP shall be submitted for COMPANY and Classification Society approval.

Prior to start of fabrication

At least 30 working days prior to start of fabrication

Inspection and Test Plans shall be submitted for COMPANY and Classification Society approval.

At least 30 working days prior to start of fabrication

A Dimensional Control Procedure shall be established by CONTRACTOR and submitted to COMPANY for approval prior to production fabrication.

Prior to start of fabrication

CONTRACTOR shall prepare an NDT plan for all Weld Mapping and NDT to be performed and shall submit the plan to COMPANY for approval.

At least 30 working days prior to start of fabrication

Submit the NDT testing company utilized by CONTRACTOR for fabrication under this Project Specification.

At least 30 working days prior to start of fabrication

Submit NDT inspection personnel qualifications.

Submitted with NDT Plan

RT procedure shall be submitted to COMPANY for approval prior to fabrication.

Submitted with NDT Plan

UT procedure shall be submitted to COMPANY for approval prior to fabrication.

Submitted with NDT Plan

MT procedure shall be submitted to COMPANY for approval prior to fabrication.

Submitted with NDT Plan

PT procedure shall be submitted to COMPANY for approval prior to fabrication.

Submitted with NDT Plan

A Weld Repair Protocol shall be established by COMPANY and submitted to COMPANY for approval prior to production fabrication.

Prior to start of fabrication

Company No._Rev. 200-22-ST-SPC-00007_00

67 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

13 APPENDICES

Appendix 1

Inspection Requirement and NDT Extent for Jacket Structures

Appendix 2

Inspection Requirement and NDT Extent for Deck Structures

Company No._Rev. 200-22-ST-SPC-00007_00

68 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

13.1 Appendix 1

Inspection Requirement and NDT Extent for Jacket Structures

INSPECTION REQUIREMENTS - JACKET STRUCTURE

CVN CLASS / INSPECTION CATEGORY

STRUCTURAL CATEGORY

ITEM DESCRIPTION

YIELD TYPE

T < 19mm

INSPECTION CATEGORY

19mm ≤ T ≤ 50mm

INSPECTION CATEGORY

T > 50mm

INSPECTION CATEGORY

2

1

1

NA

CV2Z4

CV2ZX

2

1

1

NA

CV2ZX

CV2ZX

2

1

1

2 & Note 2

NT

2 & Note 2

CV1

Notes 2 & 3

JA

Joint Cans

JB

JC

Primary Members Diagonals, Legs, Brace end stubs @nodes, Stiffener @nodes

Secondary Members Horizontal and Conductor panel framing, Knee Braces

JD1

Piling Heavy wall at mudline

JD2

Piling Elsewhere

JE

Stiffeners

JF

JG

JH

Lifting Points Padeye main plates & attachment points of the padeye to structure

Miscellaneous Conductor panels, Boat landings, Mudmats, Pile Shim, Launc Craddle

Miscellaneous Crown

I

II

III

I

II

III

I

II

III

I

II

III

I

II

III

I

II

III

I

II

III

I

II

III

I

II

Company No._Rev. 200-22-ST-SPC-00007_00

NA

CV2

CV2

NT

NT

CV2

NT

NT

CV1

NA

NA

CV2

NT

NT

CV1

CV1

CV1

NA

CV2Z5

CV2Z4

NT

NT

CV1

NA

CV2

2 & Note 2

CV1

Notes 2 & 3

1

CV2Z5

1

2 & Note 2

NT

2 & Note 2

2 & Note 2

CV1

Notes 2 & 3

Notes 2 & 3

2

2

1

CV2Z5

CV2

CV2Z5

CV2Z5

1

1

1

1

CV2

CV2X

NA

NA

NA

NA

CV2X

CV2X

2 & Note 2

NT

2 & Note 2

CV1

2 & Note 2

Notes 2 & 3

Notes 2 & 3 Notes 2 & 3

2

1

1

CV1

CV2

NT

CV1

CV2

NA

CV2Z4

CV2ZX

Notes 2 & 3

CV2

1

CV2Z5

2 & Note 2

NA

Notes 2 & 3

1

2

1

1

CV1

CV2

NA

CV2ZX

CV2ZX

2 & Note 2

NT

2 & Note 2

CV1

2 & Note 2

Notes 2 & 3

2

1

CV1

CV1

NA

CV2Z5

Notes 2 & 3 Notes 2 & 3

2

1

CV1

CV2

NA

CV2ZX

NT

2 & Note 2

1

1

2

2

2

2

1

1

Notes 2 & 3

1

1

2

Notes 2 & 3

1

2

1

1

Notes 2 & 3 Notes 2 & 3

1

2

1

69 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

INSPECTION REQUIREMENTS - JACKET STRUCTURE

CVN CLASS / INSPECTION CATEGORY

STRUCTURAL CATEGORY

ITEM DESCRIPTION

YIELD TYPE

T < 19mm

INSPECTION CATEGORY

19mm ≤ T ≤ 50mm

INSPECTION CATEGORY

T > 50mm

INSPECTION CATEGORY

Outfitting Steel Walkways, Access Platforms, Stair, Ladders

JI

Notes:

III

I

II

III

CV2

1

CV2ZX

1

CV2ZX

NT

NT

NA

2 & Note 2

2 & Note 2

2

NT

NT

NA

2 & Note 2

NA

2 & Note 2

CV1

2

NA

2

1

2

Notes 2 & 3

1. CV2ZX can be substituted where CV2X is required, but CV2X cannot be specified where CV2ZX is required

2. 10% RT of each weld shall apply for CV1 and NY Toughness Class Tubular members with DN < 400 (NPS 16)

3. Inspection Categories for CV1: 1 - for full penetration welds 1 - for stiffeners welding 1 - for Tubular with OD ≥ DN 400 1 - for Beams Depth > 457mm 1 - for Plate with WT ≥ 13mm 2 - for anything not covered above (including equipment support sole plates)

4. When two different structure groups are joined, the following are applied: - if any appurtenances attached to toughness class CV2, CV2Z4, CV2Z5, CV2X and CV2X tubular members, the inspection category will follow weld category 1 - if any TKY tubular incoming member that welded to any tubular member of joint cans/chord/brace cans with class CV2/CV2Z4/CV2Z5/CV2ZX/CV2X, the weld category 1 shall apply. - if any circumferential butt weld with equal thickness, the minimum NDT will follow the higher structure group. - if any circumferential butt weld joint with different and with tapering (to meet the lower thickness), the minimum required NDT may follow structure group of the lower thickness. In case joined with cone, the stringent of cone and lower thickness shall govern.

Company No._Rev. 200-22-ST-SPC-00007_00

70 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

13.2 Appendix 2

Inspection Requirement and NDT Extent for Deck Structures

INSPECTION REQUIREMENTS - DECK STRUCTURE

Toughness Classes (single)

Members (when different members joined, for CJP refers to the beveled member, for Fillet refers to lower thickness)

CV2s

Tubulars

Beams

Plates

Tubulars

CV1

Beams

Plates

Tubulars

Beams

Plates

Members

Tubulars

Non-tubulars (including beams, plates)

Tubulars

Non-tubulars (including beams, plates)

Tubulars

Non-tubulars (including beams, plates)

NT

Toughness Classes (Mixture)

CV1 to CV2s (vice versa)

NT to CV2s (vice versa)

NT to CV1 (vice versa)

Sizes

Any

Any

Any

NDT Categories or Percentages

CATEGORY 1

CATEGORY 1

CATEGORY 1

16in and over diameter

CATEGORY 1

lower than 16in diameter

10% RT

over 18in web depth

CATEGORY 1

18in and lower web depth

CATEGORY 2

Other/Specific:

• Splice Beam
• End connection cantilever beam
• Stiffener (plate or circular)

CATEGORY 1

13mm and over thick

CATEGORY 1

lower than 13mm thick

CATEGORY 2

16in and over diameter

CATEGORY 2

lower than 16in diameter

10% RT

Any

Any

Sizes

Any

Any

Any

Any

Any

Any

CATEGORY 2

CATEGORY 2

NDT Categories or Percentages

CATEGORY 1

Refer to “single” CV1

CATEGORY 1

Refer to “single” NT

Refer to “single” NT

Refer to “single” NT

Company No._Rev. 200-22-ST-SPC-00007_00

71 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

WELD CATEGORY

LOCATION OR TYPE OF WELD (c)

CATEGORY 1

BRACE TO CHORD WELDS, ALL T, K OR Y CONNECTION

CIRCUMFERENTIAL BUTT WELDS IN TUBULAR MEMBERS

LONGITUDINAL WELDS IN TUBULAR MEMBERS

(NOTE i) BRACE END STUBS AND OTHER TUBULARS FABRICATED FROM MATERIAL CV2

FULL PENETRATION WELDS (e.g. CJP T- JOINT, PLATE BUTT WELD, BEAM SPLICE)

FILLET AND PART PENETRATION WELDS

BRACE TO CHORD WELDS, ALL T, K OR Y CONNECTION

CATEGORY 2

CIRCUMFERENTIAL BUTT WELDS IN TUBULAR MEMBERS

LONGITUDINAL WELDS IN TUBULAR MEMBERS

VT

100

100

100

100

100

100

100

100

100

NDT EXTENT PERCENTAGE OF TOTAL WELD LENGTH (a) (d) (o)

UT (b) (l)

MT (e)

RT (b)

L1

L2

L1

L2

L1

L2

100 (k) APPLY ONLY IF DN>300 WITH WT>13mm AND LOCAL DIHEDRAL ANGLE >30o

100

10 (f) APPLY ONLY IF WT>38mm

10 (f) APPLY ONLY IF WT>38mm

10 (f) APPLY ONLY IF WT>38mm

100 (IF MEMBER WT<13mm THEN APPLY MT INSTEAD OF UT)

100 (g) (j)

100

10 (m)

100

100

20 (m)

20 (n) APPLY ONLY IF DN≥80

20 (n) APPLY ONLY IF DN≥80

10 (f) APPLY ONLY IF WT>38mm

10 (m)

Company No._Rev. 200-22-ST-SPC-00007_00

72 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

WELD CATEGORY

LOCATION OR TYPE OF WELD (c)

FULL PENETRATION WELDS (e.g. CJP T- JOINT, PLATE BUTT WELD, BEAM SPLICE)

FILLET AND PART PENETRATION WELDS

FLOOR PLATE

HANDRAILS

VT

100

100

100

100

NDT EXTENT PERCENTAGE OF TOTAL WELD LENGTH (a) (d) (o)

UT (b) (l)

MT (e)

RT (b)

L1

L2

L1

L2

L1

L2

20

10

20

10

10

5

CATEGORY DEFINITIONS

CATEGORY 1

• All WELDING OF TOUGHNESS CLASS CV2, CV2Z4, CV2Z5, CV2X, and CV2ZX MATERIALS.
• FULL PENETRATION WELDS OF TOUGHNESS CLASS CV1 MATERIAL.
• WELDING OF TOUGHNESS CLASS CV1 STIFFENERS.
• SPLICES OR END CONNECTIONS IN CANTILEVER BEAMS.
• APPURTENANCES ATTACHED TO TOUGHNESS CLASS CV2, CV2Z4, CV2Z5, CV2X, AND CV2X TUBULAR MEMBERS.
• LARGE OR THICK CV1 MATERIALS: TUBULARS WITH OD ≥ DN 400 (NPS 16), BEAMS WITH DEPTH > 457 mm (18 in.), PLATE WITH THICKNESS >= 13 mm (0.5 in.) (EXCLUDING EQUIPMENT SUPPORT SOLE PLATES)

CATEGORY 2

ANYTHINGS NOT COVERED BY CATEGORY 1

L1 L2

a

b

c

LEVEL 1 — INITIAL INSPECTION PERCENTAGE. LEVEL 2 — REDUCED INSPECTION PERCENTAGE BASED ON REJECT LEVELS BELOW 2 PERCENT FOR A SATISFACTORY PERIOD OF TIME. REDUCED INSPECTION LEVELS SHALL BE APPROVED BY COMPANY AND MAY BE REVOKED AT ANY TIME, AND WITHOUT REASON, BY COMPANY.

NOTES TO NDT EXTENT

FOR EACH WELD, THE PERCENTAGE OF TESTING SHALL BE RANDOMLY DISTRIBUTED OVER THE ENTIRE LENGTH OF THE WELD. RT CAN BE REPLACED BY PAUT (INCLUDING TOFD) IN CASES WHERE RT IS IMPRACTICAL (I.E. DUE TO PENETRATION LIMITATION OF HIGH WALL THICKNESS, CLEARANCES OR OTHER RESTRICTIONS). WHEN PAUT IS PROPOSED FOR REPLACING RT, A SPECIFIC VALIDATION/DEMONSTRATION TEST SHALL BE CARRIED-OUT AND CONSIST IN COMPARISON DETECTABILITY AND SIZING ACCURACY CAPABILITY VERSUS THE RADIOGRAPHIC TESTING OVER A DEFECTIVE WELD SAMPLE OR TEST BLOCK. ANY SUCCESSFUL VALIDATION TEST CARRIED-OUT IN PREVIOUS PROJECTS WITH SIMILAR SCOPE OF WORK AND USING SAME PROPOSED PAUT SYSTEM CONFIGURATION, CAN BE CONSIDERED FOR CURRENT PROJECT SCOPE IN LIEU OF SPECIFIC VALIDATION, PROVIDED EVIDENCE DOCUMENTATION IS SUBMITTED FOR COMPANY REVIEW AND APPROVAL

100% UT LAMINATION CHECK PRIOR TO WELD SHALL BE PERFORMED IF THE HEADER / CHORD / CANS / MAIN MEMBER MATERIALS WITH THICKNESS >20MM SHALL BE DESIGNED UNDER Z PROPERTIES, LIKE CV2Z4 / CV2Z5 /

Company No._Rev. 200-22-ST-SPC-00007_00

73 of 74

NFPS Offshore Compression Complexes Project COMP2 FABRICATION OF OFFSHORE STEEL STRUCTURES, WELDING & INSPECTION SPECIFICATION FOR CP6S AND CP7S COMPLEXES

WELD CATEGORY

LOCATION OR TYPE OF WELD (c)

NDT EXTENT PERCENTAGE OF TOTAL WELD LENGTH (a) (d) (o)

UT (b) (l)

MT (e)

RT (b)

VT

L1

L2

L1

L2

L1

L2

CV2ZX; AND THE INCOMING / ATTACHING / BRANCH MEMBER MATERIAL SHALL BE 13MM AND OVER IF FULL PENETRATION WELD, OR 13MM WELD THROAT THICKNESS IF FILLET OR PARTIAL PENETRATION WELD.

INSPECTED WELDS SHALL INCLUDE ENDS AS A MINIMUM FOR PARTIALLY INSPECTED WELDS. BALANCE OF WELD LENGTH TO BE INSPECTED ON PARTIALLY INSPECTED WELDS SHALL BE APPLIED AT RANDOM LOCATIONS ALONG THE WELD LENGTH

WHEN APPROVED IN WRITING BY COMPANY ON A CASE-BY-CASE BASIS, PT INSPECTIONS MAY SUBSTITUTE MT INSPECTION IN AREAS WHERE MT INSPECTION IS IMPOSSIBLE DUE TO LACK OF ACCESS

THICKNESS > 38 mm (1.5 in.). 10% OF EACH WELD SHALL BE INSPECTED FOR CV1 AND NT TOUGHNESS CLASS TUBULAR MEMBERS < DN 400 (NPS 16). NODE CANS AND OTHER TUBULARS FABRICATED FROM MATERIAL TOUGHNESS CLASS CV2X AND CV2ZX

BRACE END STUBS AND OTHER TUBULARS FABRICATED FROM MATERIAL CV2

ON A CASE-BY-CASE BASIS, COMPANY MAY ALLOW THE SUBSTITUTION OF UT INSPECTION IN COMBINATION WITH MT INSPECTION IN LIEU OF RT OF FULL PENETRATION CLOSING BUTT JOINTS MADE FROM ONE SIDE TUBULAR MEMBERS > DN 300 (NPS 12), WITH THICKNESS > 13 mm (0.50 in.) AND LOCAL DIHEDRAL ANGLES > 30 DEGREES. MT INSPECTION SHALL BE UTILIZED WHEN THICKNESS IS < 13 mm (0.50 in.)

WHEN LESS THAN 100 PERCENT OF WELD IS INSPECTED, THE REDUCED PERCENTAGE SHOULD INCLUDE THE INITIATION, TERMINATION, ANY DISCONTINUITIES, AND SOME MID-SPAN DISTANCE OF EACH WELD

FOR TUBULARS ≥ DN 80 (NPS 3). IF A DISCONTINUITY EXTENDS BEYOND THE PERCENTAGE OF NDT REQUIRED, THE DISCONTINUITY SHALL BE INVESTIGATED TO DETERMINE ITS FULL LENGTH. ANY CJP WELD WHICH REQUIRES UT AND HAVING SCANNING LIMITATION (i.e., PAD EYE, ETC.) SHALL BE SUBJECTED TO UT ON THE ACCESSIBLE AREAS UP TO MAXIMUM AVAILABLE EXTENT. UT LIMITATIONS SHALL BE DULY REMARKED IN THE UT REPORT. ENTIRE WELD SHALL BE ADDITIONALLY INSPECTED WITH MT

d

e

f

g

h i

j

k

l

m

n

o

p

Company No._Rev. 200-22-ST-SPC-00007_00

74 of 74

Project: Q-21699 - Saipem COMP2 Folder: Structure