Welding of Pipelines and Related Facilities

API STANDARD 1104

TWENTY-SECOND EDITION, JULY 2021

Special Notes

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Copyright © 2021 American Petroleum Institute

Foreword

This standard was prepared by a formulating committee that included representatives of the API, the American Gas Association (AGA), the Pipe Line Contractors Association (PLCA), the American Welding Society (AWS), and the American Society for Nondestructive Testing (ASNT), as well as representatives of pipe manufacturers and individuals associated with related industries.

The purpose of this standard is to present methods for the production of high quality welds through the use of qualified welders using approved welding procedures, materials, and equipment. Its purpose is also to present inspection methods to ensure the proper analysis of welding quality through the use of qualified technicians and approved methods and equipment. It applies to both new construction and in-service welding.

The use of this standard is entirely voluntary and is intended to apply to welding of piping used in the compression, pumping, and transmission of crude petroleum, petroleum products, fuel gases, carbon dioxide, and nitrogen and, where applicable, to distribution systems.

This standard represents the combined efforts of many engineers who are responsible for the design, construction, and operation of oil and gas pipelines, and the committee appreciatively acknowledges their wholehearted and valuable assistance.

Nothing contained in any API publication is to be construed as granting any right, by implication or otherwise, for the manufacture, sale, or use of any method, apparatus, or product covered by letters patent. Neither should anything contained in the publication be construed as insuring anyone against liability for infringement of letters patent.

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This document was produced under API standardization procedures that ensure appropriate notification and participation in the developmental process and is designated as an API standard. Questions concerning the interpretation of the content of this publication or comments and questions concerning the procedures under which this publication was developed should be directed in writing to the Director of Standards, American Petroleum Institute, 200 Massachusetts Avenue, Suite 1100, Washington, DC 20001. Requests for permission to reproduce or translate all or any part of the material published herein should also be addressed to the director.

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Suggested revisions are invited and should be submitted to the Standards Department, API, 200 Massachusetts Avenue, Suite 1100, Washington, DC 20001, standards@api.org.

iii

Contents

Page

1. Scope 1

2. Normative References 1

3. Terms, Definitions, Acronyms, and Abbreviations 2

   1. Terms and Definitions 2

   2. Acronyms and Abbreviations 8

4. Specifications 11

   1. Equipment 11

   2. Materials 12

5. Qualification of Welding Procedures with Filler Metal Additions 13

   1. Procedure Qualification 13

   2. Record 13

   3. Welding Procedure Specification 13

   4. Essential Variables 19

   5. Welding of Test Joints-Butt Welds 22

   6. Testing of Welded Joints-Butt Welds 22

   7. Welding of Test Joints-Branch and Fillet Welds 30

   8. Testing of Welded Joints-Branch and Fillet Welds 31

6. Qualification of Welders 32

   1. General 32

   2. Single Qualification 33

   3. Multiple Qualification 36

   4. Visual Examination 40

   5. Destructive Testing 40

   6. Nondestructive Testing (NDT)-Butt Welds Only 41

   7. Retesting and Disposition of Test Results 42

   8. Records 42

7. Design and Preparation of a Joint for Production Welding 42

   1. General 42

   2. Alignment 42

   3. Use of Lineup Clamp for Butt Welds 43

   4. Bevel 43

   5. Weather Conditions 43

   6. Clearance 43

   7. Cleaning Between Beads 43

   8. Position and Roll Welding 43

   9. Identification of Welds 44

   10. Preheat, Interpass Temperature, Postheat, and PWHT 44

8. Inspection and Testing of Production Welds 44

   1. Rights of Inspection 44

   2. Methods of Inspection 44

   3. Qualification of Inspection Personnel 44

   4. Certification of NDT Personnel 45

9. Acceptance Standards for NDT 45

   1. General 45

   2. Rights of Rejection 45

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   3. Radiographic Testing 46

   4. Magnetic Particle Testing 52

   5. Liquid Penetrant Testing 53

   6. Ultrasonic Testing 54

   7. Visual Acceptance Standards for Undercutting 56

   8. Visual Acceptance Standards for Internal Concavity 56

10. Repair and Removal of Weld Defects 56

    1. General 56

    2. Repair Requirements 57

    3. Repair Procedure 58

    4. Repair Welder Qualification 67

    5. Inspection of Repair Welding 71

    6. NDT and Weld Repair Acceptance Criteria 71

11. Procedures for Nondestructive Testing (NDT) 71

    1. General 71

    2. Magnetic Particle Testing Method 83

    3. Liquid Penetrant Testing Method 83

    4. Ultrasonic Testing Methods 83

12. Mechanized Welding with Filler Metal Additions 94

    1. Acceptable Processes 94

    2. Procedure Qualification 94

    3. Record 95

    4. Welding Procedure Specification 95

    5. Essential Variables 99

    6. Testing of Welded Joints-Butt Welds 102

    7. Qualification of Welding Operators 107

    8. Records of Qualified Operators 111

    9. Inspection and Testing of Production Welds 111

    10. Acceptance Standards for NDT 111

    11. Repair and Removal of Defects 111

    12. Radiographic Testing 111

    13. Ultrasonic Testing 111

Annex A (normative) Alternative Acceptance Standards for Girth Welds 112

Annex B (normative) In-service Welding 137

Annex C (normative) Requests for Interpretation and Requests for Revision to the Document 161

Bibliography 163

Figures

1. Sample Qualification Weld Report Form 15

2. Sample Welding Procedure Specification Form 16

3. Location of Test Butt Weld Specimens for Procedure Qualification Test 23

4. Tension Test Specimen 25

5. Nick Break Test Specimen 27

6. Dimensioning of Imperfections in Exposed Weld Surfaces 28

7. Root and Face Bend Test Specimen: Wall Thicknesses Less than or Equal to 0.500 in. (12.7 mm) 28

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8. Jig for Guided-bend Tests 29

9. Side Bend Test Specimen: Wall Thicknesses Greater than 0.500 in. (12.7 mm) 30

10. Location of Nick Break Test Specimens: Branch and Fillet Weld Procedure

    and Welder Qualification Test Welds 30

11. Location of Nick Break Test Specimens: Branch and Fillet Weld Procedure and Welder

    Qualification Test Welds, Including Size-to-size Branch Connection Welder Qualification Test 31

12. Location of Test Butt Weld Specimens for Welder Qualification Test (Full Circumference) 38

13. Location of Test Butt Weld Specimens for Welder Qualification Test (Half Circumference) 39

14. Inadequate Penetration Without High-low 46

15. Inadequate Penetration Due to High-low 46

16. Inadequate Cross Penetration 47

17. Incomplete Fusion at Root of Bead or Top of Joint 47

18. Incomplete Fusion Due to Cold Lap 48

19. Internal Concavity 48

20. Maximum Distribution of Gas Pockets: Wall Thickness (t) less than or equal to 0.500 in. (12.7 mm) . . 50

21. Maximum Distribution of Gas Pockets: Wall Thickness (t) Greater Than 0.500 in. (12.7 mm) 51

22. Hardness Locations for Full-thickness Repair Procedure Qualification 64

23. Hardness Locations for External Partial-thickness Repair Procedure Qualification at Weld 64

24. Hardness Locations for Cover Pass Repair Procedure at Weld Centerline 65

25. Hardness Location for Back Weld Repair or Internal Partial-Thickness Repair Procedure

    at Weld Centerline 65

26. Hardness Locations for Cover Pass Repair Procedure at Fusion Line 66

27. Hardness Locations for External Partial-Thickness Repair at Fusion Line 66

28. Calculation for Determining Beam Width 75

29. Example of Reference Standard for Manual Ultrasonic Testing 89

30. Example: Establishing Distance, Refracted Angle, and Velocity 89

31. Example: Attenuation and Transfer Procedure 90

32. Example: V Prep Reference Standard—Example Reflector Positioning 93

33. Example: J and K Prep Reference Standard—Reflector Positioning 93

34. Example—J Prep Reference Standard—Top View 93

35. Sample Coupon Test Report 96

36. Sample Welding Procedure Specification Form 97

37. Location of Test Butt Weld Specimens for Procedure Qualification Test 104

38. Tension Test Specimen 105

39. Root and Face Bend Test Specimen: Wall Thicknesses Less Than or Equal to 0.500 in. (12.7 mm) . . 106 40 Jig for Guided-bend Tests 106

41 Side Bend Test Specimen: Wall Thicknesses Greater than 0.500 in. (12.7 mm) 107

1. Top View (Width in Circumferential Direction) of the Tensile Test Specimen 118

2. Charpy Specimen and V-notch Location for HAZ Impact Testing 119

3. Orientation of CTOD Test Specimen 120

4. Machining Objective for CTOD Test Specimen with Respect to Pipe Wall 121

5. Location of Notch for Weld Metal Specimen 122

6. Location of Notch for Heat-affected Zone Specimen 122

7. Option 1 Imperfection Limits for CTOD ≥ 0.010 in. (0.25 mm) 124

8. Option 1 Imperfection Limits for 0.004 in. (0.10 mm) ≤ CTOD < 0.010 in. (0.25 mm) 125

9. Allowable Imperfection Size Curves Before and After Height Adjustment 128

10. Schematic Overview of the Option 2 Procedure 128

11. Criteria for Evaluation of Imperfection Interaction 136

1. Examples of Typical Temper Bead Deposition Sequences 138

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2. An Example of Procedure and Welder Qualification Test Assembly 143

3. Suggested Location of Test Specimens 144

4. Suggested Location of Test Specimens for Weld Deposition Repair 145

5. Example Macro Test Specimen—In-service Fillet Welds 147

6. Face Bend Test Specimen 149

7. Reinforcing Pad 153

8. Reinforcing Saddle 154

9. Encirclement Sleeve 154

10. Encirclement Tee 155

11. Encirclement Sleeve and Saddle 155

12. Encirclement Saddle 156

Tables

1. Essential Variables for Qualification of Welding Procedure Specifications 20

2. Filler Metal Groups 22

3. Type and Number of Test Specimens for Procedure Qualification Test 24

4. Filler Metal Groups for Welder Qualification 33

5. Qualified Thickness Range for Single Qualification Test 35

6. Qualification Scope for Single Qualification Test Using a Branch Connection 36

7. Type and Number of Butt Weld Test Specimens per Welder for Welder

   Qualification Test and Destructive Testing of Production Welds 41

8. Maximum Dimensions of Undercutting 56

9. Essential Variables for Qualification of Repair Welding Procedure Specifications 60

10. Repair Type Qualification Matrix 60

11. Type and Number of Butt Weld Test Specimens per Repair Type for Repair Procedure 62

12. Repair Weld Maximum Hardness Values, Non-Sour Service, HV10 67

13. Repair Welder Qualification Scope 68

14. Type and Number of Butt Weld Test Specimens per Repair Type for Repair Welder Qualification 69

15. Essential Variables for Repair Welders 70

16. Repair Welder Qualification Matrix 71

17. ASTM E747 Wire Type IQI Selection 77

18. ISO Wire Type IQI Selection 77

19. ASTM E1025 Hole Type IQI Selection 77

20. Essential Variables for the Qualification of Mechanized Welding Procedure Specifications 100

21. Filler Metal Groups 102

22. Type and Number of Test Specimens for Procedure Qualification Test 103

23. Type and Number of Test Specimens for Welding Operator Qualification Test 109

1. Essential Variables for Qualification of Welding Procedure Specifications in Accordance

   with this Annex 116

2. Allowed Range of Variation from the Targeted Mean Values for a Lot Defined by

   Controlled Chemical Composition 117

3. Initial Allowable Imperfection Size for Pr = 0.825 126

4. Example Acceptance Table 128

5. Acceptance Limits for Buried Volumetric Imperfections 133

6. Acceptable Limits for Unrepaired Arc Burns 133

1. Essential Variables for Qualification of Welding Procedure Specifications in Accordance

   with this Annex 140

2. Essential Variables Applicable to Procedure and Welder Qualification 141

3. Type and Number of Specimens—In-service Welding Procedure Qualification Test 146

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4. Weld Maximum Hardness Values, Non-Sour Service, HV 148

5. Type and Number of Test Specimens for Longitudinal Groove Seam—Welder Qualification 152

6. Essential Variables for Qualification of Repair Welding Procedure Specifications

   in Accordance with this Annex 158

7. Type and Number of Specimens—In-service Welding Repair Procedure Qualification Test 159

Welding of Pipelines and Related Facilities

1. Scope

   
   

   This standard covers the gas and arc welding of butt, branch, and fillet welds in carbon and low-alloy steel pipe and piping components used in the compression, pumping, and transmission of crude petroleum, petroleum products, fuel gases, carbon dioxide, nitrogen, and, where applicable, covers welding on distribution systems. It applies to both new construction and in-service welding. The welding may be done by a shielded metal arc welding, submerged arc welding, gas tungsten arc welding, gas metal arc welding, flux- cored arc welding, plasma arc welding, or oxyacetylene welding process, or by a combination of these processes using a manual, semiautomatic, or mechanized welding technique or a combination of these techniques. The welds may be produced by position or roll welding or by a combination of position and roll welding.

   
   

   This standard also covers the procedures for radiographic, magnetic particle, liquid penetrant, and ultrasonic testing, as well as the acceptance standards to be applied to production welds tested to destruction or inspected by radiographic, magnetic particle, liquid penetrant, ultrasonic, and visual testing methods.

   
   

   The values stated in either U.S. customary units (USC) or metric units (SI) are to be regarded separately as standard. Each system is to be used independently of the other, without combining values in any way.

   
   

   The figures depicted in this standard are not drawn to scale.

   
   

   It is intended that all work performed in accordance with this standard meets or exceeds the requirements of this standard.

   
   

   While this standard is comprehensive, it may not address all issues that may arise. The absence of guidance or requirements is not to be considered prohibitive to a particular activity or approach that is based upon sound engineering judgment. For example, other industry standards, reliable engineering tests and analyses, or established industry practices may provide useful reference to establish sound engineering judgment.

   
   

2. Normative References

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

API Specification 5L, Specification for Line Pipe

ASNT1 SNT-TC-1A, Recommended Practice for Personnel Qualification and Certification in Nondestructive Testing

ASTM2 E23, Standard Test Methods for Notched Bar Impact Testing of Metallic Materials

ASTM E165, Standard Test Method for Liquid Penetrant Examination

ASTM E384, Standard Test Method for Knoop and Vickers Hardness of Materials

ASTM E709, Standard Guide for Magnetic Particle Testing

ASTM E747, Standard Practice for Design, Manufacture and Material Grouping Classification of Wire Image Quality Indicators (IQI) Used for Radiology

1 American Society for Nondestructive Testing, 1711 Arlingate Lane, Columbus, Ohio 43228-0518, www.asnt.org.

2 ASTM International, 100 Barr Harbor Drive, West Conshohocken, Pennsylvania 19428, www.astm.org.