API Standard 1104. Welding of Pipelines and Related Facilities. 21-th edition

This standard presents methods for the production of high-quality welds through the use of qualified welders using approved welding procedures, materials, and equipment. This standard covers the gas and arc welding of butt, fillet, and socket welds in carbon and low-alloy steel piping 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, oxyacetylene welding, or flash butt-welding process or by a combination of these processes using a manual, semiautomatic, mechanized, or automatic 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 presents inspection methods to ensure the proper analysis of welding quality through the use of qualified technicians and approved methods and equipment. It 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. 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. Cover ......Page 1 Special Notes......Page 2 Foreword......Page 3 Contents......Page 5 2 Normative References......Page 9 3.1 Terms and Definitions......Page 10 3.2 Acronyms and Abbreviations......Page 13 4.2 Materials......Page 16 5.3 Welding Procedure Specification......Page 17 5.4 Essential Variables......Page 21 5.6 Testing of Welded Joints—Butt Welds......Page 24 Figure 9—Side Bend Test Specimen: Wall Thicknesses Greater than 0.500 in. (12.7 mm)......Page 31 6.2 Single Qualification......Page 33 6.3 Multiple Qualification......Page 34 6.4 Visual Examination......Page 36 6.5 Destructive Testing......Page 37 Table 3—Type and Number of Butt Weld Test Specimens per Welder for Welder Qualification Test and Destructive Testing of Production Welds......Page 38 7.6 Clearance......Page 39 7.11 Preheat and PWHT......Page 40 8.4 Certification of NDT Personnel......Page 41 Figure 13—Inadequate Penetration Without High-low......Page 42 9.4 Magnetic Particle Testing......Page 49 9.5 Liquid Penetrant Testing......Page 50 9.6 Ultrasonic Testing......Page 51 Table 4—Maximum Dimensions of Undercutting......Page 53 10.3 Repair Procedure......Page 55 Table 6—Repair Weld Maximum Hardness Values, HV10 a......Page 61 Table 7—Type and Number of Butt Weld Test Specimens per Repair Type for Repair Welder Qualification......Page 62 11.1 Radiographic Test Methods......Page 63 11.4 Ultrasonic Test Methods......Page 68 12.4 Welding Procedure Specification......Page 74 12.5 Essential Variables......Page 76 12.6 Qualification of Welding Equipment and Operators......Page 78 12.12 Ultrasonic Testing......Page 79 Figure 30—Location of Test Butt Weld Specimens for Flash Weld Procedure Qualification Test: Outside Diameter Greater Than 18 in. (457 mm) but Less Than or Equal to 24 in. (610 mm)......Page 80 13.5 Essential Variables......Page 84 13.8 Quality Assurance of Production Welds......Page 85 13.10 Repair and Removal of Defects......Page 86 13.11 Radiographic Procedure......Page 87 Annex A (normative) Alternative Acceptance Standards for Girth Welds......Page 88 Annex B (normative) In-service Welding......Page 110 Annex C (normative) Requests for Interpretation and Request for Revision to the Document......Page 125 Tables ......Page 0 Figure 1—Sample Welding Procedure Specification Form......Page 18 Figure 2—Sample Coupon Test Report......Page 19 Figure 3—Location of Test Butt Weld Specimens for Procedure Qualification Test......Page 25 Figure 4—Tension Test Specimen......Page 27 Figure 5—Nick Break Test Specimen......Page 28 Figure 7—Root and Face Bend Test Specimen: Wall Thicknesses Less Than or Equal to 0.500 in. (12.7 mm)......Page 29 Figure 8—Jig for Guided-bend Tests......Page 30 Figure 11—Location of Nick Break Test Specimens: Fillet Weld Procedure and Welder Qualification Test Welds, Including Size-to-size Branch Connection Welder Qualification Test......Page 32 Figure 12—Location of Test Butt Weld Specimens for Welder Qualification Test......Page 35 Figure 15—Inadequate Cross Penetration......Page 43 Figure 18—Internal Concavity......Page 44 Figure 19—Maximum Distribution of Gas Pockets: Wall Thickness (t) Less Than or Equal to 0.500 in. (12.7 mm)......Page 47 Figure 20—Maximum Distribution of Gas Pockets: Wall Thickness (t) Greater Than 0.500 in. (12.7 mm)......Page 48 Figure 21—Hardness Locations for Full Thickness Repair Procedure Qualification......Page 58 Figure 23—Hardness Locations for Cover Pass Repair Procedure at Weld Centerline......Page 59 Figure 26—Hardness Locations for Partial Thickness Repair at Fusion Line......Page 60 Figure 28—Establishing Distance, Refracted Angle, and Velocity......Page 72 Figure 29—Transfer Procedure......Page 73 Figure 32—Location of Test Butt Weld Specimens for Flash Weld Procedure Qualification Test: Outside Diameter Greater Than 30 in. (762 mm)......Page 81 Figure 33—Two-in. Nick Break Test Specimen......Page 83 Figure A.1—Top View (Width in Circumferential Direction) of the Tensile Test Specimen......Page 94 Figure A.2—Charpy Specimen and V-notch Location for the HAZ Impact Testing......Page 95 Figure A.4—Machining Objective for CTOD Test Specimen with Respect to Pipe Wall......Page 96 Figure A.6—Location of Notch for Heat-affected Zone Specimen......Page 97 Figure A.7—Option 1 Imperfection Limits for CTOD 3 0.010 in. (0.25 mm)......Page 99 Figure A.8—Option 1 Imperfection Limits for 0.004 in. (0.10 mm) £ CTOD < 0.010 in. (0.25 mm)......Page 100 Table A.3—Example Acceptance Table......Page 102 Figure A.10—Schematic Overview of the Option 2 Procedure......Page 103 Figure A.11—Criteria for Evaluation of Imperfection Interaction......Page 109 Figure B.1—Examples of Typical Temper Bead Deposition Sequences......Page 111 Figure B.2—Suggested Procedure and Welder Qualification Test Assembly......Page 113 Figure B.3—Suggested Location of Test Specimens for Sleeve and Branch Welds......Page 115 Figure B.4—Suggested Location of Test Specimens for Weld Deposition Repair......Page 116 Table B.1—Type and Number of Specimens—In-service Welding Procedure Qualification Test......Page 117 Figure B.6—Face Bend Test Specimen......Page 118 Figure B.7—Reinforcing Pad......Page 120 Figure B.9—Encirclement Sleeve......Page 121 Figure B.11—Encirclement Sleeve and Saddle......Page 122 Figure B.12—Encirclement Saddle......Page 123 Table 1—Filler Metal Groups......Page 23 Table 2—Type and Number of Test Specimens for Procedure Qualification Test......Page 26 Table 5—Type and Number of Butt Weld Test Specimens per Repair Type for Repair Procedure Qualification......Page 56 Table 9—Weld Thickness vs Diameter of ISO Wire Type IQI......Page 66 Table 10—Type and Number of Test Specimens for Procedure Qualification Test (Flash Weld Only)......Page 82 Table A.1—Allowed Range of Variation from the Targeted Mean Values for a Lot Defined by Controlled Chemical Composition......Page 92 Table A.2—Initial Allowable Imperfection Size for Pr = 0.825......Page 101 Table A.4—Acceptance Limits for Buried Volumetric Imperfections......Page 107 Table A.5—Acceptable Limits for Unrepaired Arc Burns......Page 108 Table B.2—Type and Number of Test Specimens for Longitudinal Seam Welds—Welder Qualification Test......Page 119