1、 Guide for the Certification of Offshore Mooring Chains GUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN MAY 2017 American Bureau of Shipping Incorporated by Act of Legislature of the State of New York 1862 2017 American Bureau of Shipping. All rights reserved. ABS Plaza 16855 Northchase Drive
2、Houston, TX 77060 USA Foreword Foreword This is the fourth edition of the Guide for the Certification of Offshore Mooring Chain, following from the 1986, 1999 and 2009 versions. Based on IACS UR W22, this new version adds requirements for thimbles, introduces qualification of higher grades to cover
3、lower grades, and includes more detail on CTOD tests, furnace calibration, guidance on failed proof load tests, and more detail on NDE. This Guide supersedes previous versions and ABS encourages its immediate application. Compliance with this edition is required for offshore units and single point m
4、oorings contracted for construction on or after 1 July 2017 and when the application for certification of chains and accessories is dated on or after 1 July 2017. Users are advised to check periodically on the ABS website www.eagle.org to verify that this version of this Guide is the most current. W
5、e welcome your feedback. Comments or suggestions can be sent electronically by email to rsdeagle.org. ii ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2017 Table of Contents GUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN CONTENTS SECTION 1 General Requirements . 1 1 Scope 1 1.1 Ap
6、plication . 1 1.3 Mooring Equipment . 1 1.5 Studless Chain 1 1.7 Chafing Chain 1 1.9 Special Subsea Mooring Connectors 1 3 Chain and Accessory Grades . 2 3.1 R3, R3S, R4, R4S, and R5 2 3.3 R4S and R5 . 2 3.5 Approval 2 5 Chain Manufacturer Approval . 3 5.1 Approval of Chain Manufacturers 3 5.3 Manuf
7、acturing Process Approval . 3 5.5 CTOD Tests (Crack Tip Opening Displacement Tests) . 3 5.7 Furnace Calibration . 4 5.9 R4S and R5 Additional Requirements . 4 5.11 Qualification Testing 5 7 Approval of Quality Systems at Chain Manufacturers and Bar Producers 6 7.1 Quality Provision . 6 7.3 Procedure
8、s for Obtaining Approval . 7 7.5 Quality Assurance Certificate 8 7.7 Test Data and Documentation . 8 9 Approval of Steel Mills Rolled Bar and Plate for Chain and Accessories . 8 9.1 Bar and Plate Material for Chain and Accessories, Including Pins . 8 9.3 Approval Restrictions 8 9.5 Chemical Composit
9、ion 9 9.7 Heat Treatment Sensitivity Study for Rolled Bars 9 9.9 Strain Aging, Temper Embrittlement, Hydrogen Embrittlement . 9 11 Accessory Manufacturer Approval 9 11.1 Approval of Forges and Foundries Accessories . 9 11.3 Approval Restrictions 9 11.5 Forging Reduction Ratio 10 ABSGUIDE FOR THE CER
10、TIFICATION OF OFFSHORE MOORING CHAIN .2017 iii 11.7 Chemical Composition . 10 11.9 Strain Aging, Temper Embrittlement, Hydrogen Embrittlement . 10 11.11 Heat Treatment Sensitivity Study. 10 11.13 CTOD Tests (Crack Tip Opening Displacement Tests) . 10 11.15 Furnace Calibration . 11 11.17 R4S and R5 A
11、dditional Requirements . 11 11.19 Manufacturing Process Approval . 12 11.21 Qualification Testing 12 13 Approval of Quality Systems at Accessory Manufacturers and Steel Producers 13 13.1 Quality Provision 13 13.3 Procedures for Obtaining Approval 14 13.5 Quality Assurance Certificate 14 13.7 Test Da
12、ta and Documentation . 15 TABLE 1 Mechanical Properties of Offshore Mooring Chain and Accessories . 2 TABLE 2 Minimum CTOD Values for Chain Type 4 TABLE 3 Minimum CTOD Test Values for Accessories 10 FIGURE 1 CTOD Test Specimen Location in Chain 4 FIGURE 2 Microspecimens 6 FIGURE 3 Location of CTOD T
13、est Specimens 11 SECTION 2 Material Requirements for Chain and Accessories . 16 1 Scope 16 3 Rolled Steel Bars 16 3.1 Steel Bar Manufacture . 16 3.3 Chemical Composition . 16 3.5 Mechanical Tests . 16 3.7 Dimensional Tolerances 18 3.9 Nondestructive Examination and Repair 19 3.11 Marking 19 3.13 Hea
14、t Treatment of Rolled Bars Intended for Accessory Pins . 19 5 Forged Steel 20 5.1 Forged Steel Accessories 20 5.3 Chemical Composition . 20 5.5 Heat Treatment 20 5.7 Mechanical Properties . 20 5.9 Mechanical Tests . 21 5.11 Nondestructive Examination and Repair 22 5.13 Marking 22 7 Cast Steel 22 7.1
15、 Cast Steel Accessories 22 7.3 Chemical Composition . 23 7.5 Heat Treatment 23 7.7 Mechanical Properties . 23 iv ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2017 7.9 Mechanical Tests 23 7.11 Nondestructive Examination and Repair . 24 7.13 Marking 25 9 Materials for Studs 25 TABLE 1 Dim
16、ensional Tolerance of Bar Stock. 18 FIGURE 1 Sampling for Tension Specimens and Charpy V-Notch Specimens: Steel Bars, Forgings and Castings 18 SECTION 3 Design and Manufacture of Chain and Accessories . 26 1 Design . 26 1.1 Design Details . 26 1.3 Stud Link Chain . 26 1.5 Kenter Shackles 26 1.7 Spec
17、ial Subsea Mooring Connectors 26 1.9 Ancillary Accessory Components 26 3 Chain Cable Manufacturing Process 27 3.1 Joining Shackles and Splice Links 27 5 Chain Cable Manufacturing Process Records 27 5.1 Bar Heating . 27 5.3 Flash Welding of Chain Cable . 27 5.5 Heat Treatment of Chain Cable . 28 7 Me
18、chanical Properties 28 9 Proof and Breaking Test Loads 28 11 Freedom from Defects 28 13 Dimensions and Dimensional Tolerances 29 13.1 Link Shape and Proportion 29 13.3 Tolerances Applicable to Chain Links . 29 15 Stud Link Chain Welding of Studs . 32 15.1 Heat Treatment of Welded Studs 32 15.3 Exten
19、t of Stud Weld . 32 15.5 Single Weld . 32 15.7 Weld Procedure Studs 33 15.9 Fillet Size . 33 15.11 Weld Quality 33 15.13 Stud Weld Inspection 33 17 Connecting Common Links (Splice Links) 33 17.1 Procedure Approval . 33 17.3 Adjacent Links to Splice Links . 33 17.5 Testing and Inspection 33 17.7 Iden
20、tification 33 TABLE 1 Formulas for Proof and Break Test Loads, Weight, and Length Over 5-Links 29 TABLE 2 Diameter Tolerance of Finished Chain . 30 ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2017 v FIGURE 1 Test Sample Locations in Link 28 FIGURE 2A Proportions, Dimensions and Toleran
21、ces of Stud Link Common Link 31 FIGURE 2B Proportions, Dimensions and Tolerances of Studless Common Link 32 SECTION 4 Testing and Inspection of Finished Chain . 34 1 General . 34 3 Proof and Break Load Tests . 34 3.1 Proof Load Test . 34 3.3 Break Test Specimens . 34 5 Dimensions and Dimensional Tol
22、erances 35 5.1 Individual Link Measurement After Proof Load . 35 5.3 Five-Link Measurement After Proof Load . 35 7 Mechanical Tests on Completed Chain After Proof Load 35 7.1 Specified Tests 35 7.3 Test Frequency and Properties . 36 7.5 Frequency of Crown Impact Tests . 36 7.7 Hardness Tests 36 9 No
23、ndestructive Examination After Proof Load Test . 36 9.1 Visual Inspection 36 9.3 Nondestructive Examination General . 36 9.5 Magnetic Particle Inspection (MT) . 36 9.7 Ultrasonic Testing (UT) 37 11 Retest, Rejection and Repair Criteria . 37 11.1 Measurement of Five Links 37 11.3 Replacement of Defec
24、tive Links 37 11.5 Surface Defects . 38 11.7 Volumetric Defects . 38 11.9 Geometrical or Tolerance Failure 38 11.11 Break Load Test Failure 38 11.13 Proof Load Test Failure . 38 11.15 Tensile Test Failure . 39 11.17 Charpy Test Failure . 39 13 Marking . 39 13.1 Locations for Marking of Chain 39 13.3
25、 Markings 39 13.5 Chain Certificate 40 15 Manufacturers Documentation . 40 TABLE 1 Frequency of Break and Mechanical Tests 35 vi ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2017 SECTION 5 Testing and Inspection of Accessories 41 1 General . 41 1.1 Accessory Manufacturing Process 41 1.3
26、 Accessory Manufacturing Process Records 41 3 Proof and Break Load Tests . 41 3.1 Proof Load Test . 41 3.3 Break Load Test 41 3.5 Definition of a Batch 42 3.7 Accessories Subjected to Break Test 42 3.9 Over-Designed Accessories 42 5 Dimensions and Dimensional Tolerances 42 5.1 Dimensional Tolerances
27、 42 7 Mechanical Tests 43 7.1 Test Location of Forged Shackles . 43 7.3 Test Location of Cast Shackles . 43 7.5 Complex Geometry Accessories . 43 7.7 Individual Accessories or Small Batches . 43 7.9 Definition of a Batch 44 7.11 Test Location of Pins . 44 9 Nondestructive Examination After Proof Loa
28、d Test . 44 9.1 Visual and Surface Examination 44 9.3 Nondestructive Examination General . 44 9.5 Manufacturers Statement . 45 11 Test Failures . 45 13 Marking and Certification 46 13.1 Marking 46 13.3 Certificates 46 15 Documentation 46 FIGURE 1 Pin Heat Treatment Buffer 44 APPENDIX 1 Chafing Chain
29、 for Single Point Mooring Arrangements . 47 1 Scope 47 3 Approval of Manufacturing 47 5 Materials 47 7 Design, Manufacturing, Testing and Certification . 47 ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2017 vii This Page Intentionally Left Blank Section 1: General Requirements SECTION 1
30、 General Requirements 1 Scope 1.1 Application (1 May 2017) This Guide supersedes previous versions and ABS encourages its immediate application. Compliance with this edition is required for offshore units and single point moorings contracted for construction on or after 1 July 2017 and when the appl
31、ication for certification of chains and accessories is dated on or after 1 July 2017. These requirements apply to the materials, design, manufacture, and testing of offshore mooring chain and accessories intended to be used for temporary and permanent applications such as: mooring of mobile offshore
32、 units, mooring of floating production units, mooring of offshore loading systems, and mooring of gravity based structures during fabrication. 1.3 Mooring Equipment (1 May 2017) Mooring equipment covered is common stud and studless links, connecting common links (splice links), enlarged links, end l
33、inks, detachable connecting links (shackles), end shackles, double pinned H-type links, tri-plates and shackles, subsea mooring hooks, and H-links specifically designed for chain to wire/polyester rope connections and thimbles. Mooring foundation shackles and anchor shackles for mooring are also to
34、comply with the requirements of this Guide. In addition, accessories specifically designed for temporary applications, such as pear links, Kenter shackles, swivels and swivel shackles, and similar designs are covered. 1.5 Studless Chain Studless link chain is normally deployed only once, being inten
35、ded for long-term permanent mooring systems with pre-determined design life. 1.7 Chafing Chain (1 May 2017) Requirements for chafing chain for Emergency Towing Arrangement (ETA) are given in 3-5-1/17 of the ABS Rules for Building and Classing Steel Vessels. In addition, recognized industry standards
36、 such as OCIMF may be applied. Also refer to Appendix 1 for the requirements applying to chafing chain for single point mooring arrangements (short lengths approximately 8 m). Materials requirements are to comply with applicable parts of this Guide. 1.9 Special Subsea Mooring Connectors In the case
37、of specially designed subsea connectors, these requirements are in general applicable. However, consideration will be given to unique designs, validated by first principles engineering, with mechanical and material properties different from those herein. ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MO
38、ORING CHAIN .2017 1 Section 1 General Requirements 3 Chain and Accessory Grades 3.1 R3, R3S, R4, R4S, and R5 Depending on the nominal tensile strength of the steels used for manufacture, chains are to be subdivided into five grades (i.e., R3, R3S, R4, R4S, and R5). Refer to Section 1, Table 1 below
39、for mechanical properties. 3.3 R4S and R5 (1 May 2017) Manufacturers proprietary specifications for R4S and R5 may vary subject to design conditions and material physical properties, therefore more detailed information regarding design, manufacture, testing, and specifications are to be submitted to
40、 ABS. 3.5 Approval (1 May 2017) Each grade of chain or accessory is to be individually approved. Approval for a higher grade does not constitute approval of a lower grade. If it is demonstrated to the satisfaction of ABS Materials engineering that the higher and lower grades are produced to the same
41、 manufacturing procedure using the same chemistry and heat treatment, consideration will be given to qualification of a lower grade by a higher grade. The parameters applied during qualification are not to be modified during production. Approved manufacturers will be included in the list of ABS Appr
42、oved Manufacturers on the ABS website. The approval will indicate the Company, grade, product, maximum size, and any limitations. TABLE 1 Mechanical Properties of Offshore Mooring Chain and Accessories Grade Yield Strength (1)minimum N/mm2(kg/mm2, ksi) Tensile Strength (1)minimum N/mm2(kg/mm2, ksi)
43、Elongation in 5D minimum in percent Reduction of Area minimum in percent (3)Charpy V-Notch impact Tests Energy in Joules Minimum Average Temp. C (2)Average for Base Metal Average at Flash Weld R3 410 (42, 59) 690 (70, 100) 17 500 20 60 40 50 30 R3S 490 (50, 71) 770 (78, 112) 15 (5)50 (5)0 20 65 45 5
44、3 33 R4 580 (59, 84) 860 (87, 125) 12 (5) 50 (5) 20 50 36 R4S (4)700 (71, 101) 960 (98, 139) 12 (5)50 (5) 20 56 40 R5 (4)760 (77, 110) 1000 (102, 145) 12 (5) 50 (5)20 58 42 Notes 1 Aim value of yield to tensile ratio: 0.92 maximum. 2 At the option of ABS, the impact test of Grade R3 and R3S may be c
45、arried out at either 0C or minus 20C to meet the indicated values. It is not required to Charpy test at both temperatures. 3 Reduction of area of cast steel accessories is to be for Grades R3 and R3S: minimum 40%; for Grades R4, R4S, and R5: minimum 35%, 4 Surface hardness tests are required for R4S
46、 and R5 chain and accessories. The target maximum hardness for R4S is HB330 and for R5 is HB340. Two hardness tests at each end 180 apart of chain links or accessories are to be taken. 5 For chain cross-weld tensile tests, these properties are to be reported for information only; the stated requirem
47、ents do not apply. 2 ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2017 Section 1 General Requirements 5 Chain Manufacturer Approval 5.1 Approval of Chain Manufacturers (1 May 2017) Offshore mooring chains are to be manufactured only by works approved by ABS. For this purpose, approval t
48、ests are to be carried out, the scope of which is to include proof and breaking load tests, measurements, and mechanical tests, including fracture mechanics tests. Approval will be given only after successful testing of the completed chain. The approval for each grade will normally be limited up to
49、the maximum chain diameter tested. Chain manufacturers are to have a documented and effective quality system approved by ABS. The provision of such a quality system is required in addition to, and not in lieu of, the witnessing of tests by a Surveyor as specified in Sections 2 to 5 of these requirements. Welding repair of the chain links is not permitted. 5.3 Manufacturing Process Approval (1 May 2017) Manufacturers are to submit for review and approval the sequence of operations from receiving inspection to shipment, including details of the follo
