1、 Guide for the Certification of Offshore Mooring Chains GUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN DECEMBER 2009 (Updated February 2014 see next page) American Bureau of Shipping Incorporated by Act of Legislature of the State of New York 1862 Copyright 2009 American Bureau of Shipping AB
2、S Plaza 16855 Northchase Drive Houston, TX 77060 USA Updates February 2014 consolidation includes: December 2009 version plus Corrigenda/Editorials ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2009 iii Foreword Foreword This is the third edition of the Guide for the Certification of Off
3、shore Mooring Chain, following from the 1986 and 1999 versions. This new version adds two higher strength grades R4S and R5 (the previous Q identification letter has been dropped) to the existing R3, R3S, and R4 and addresses studded and studless flash butt welded chain, chafing chain, chain accesso
4、ries, and special subsea connectors. The Guide includes additional requirements for the qualification of manufacturers, especially with respect to forged and cast accessories, and has defined certain aspects of manufacturing controls more comprehensively. This Guide supersedes previous versions and
5、ABS encourages its immediate application. Compliance with this edition is required for offshore mooring chain and accessories with a date of purchase order of the materials on or after 1 July 2011. iv ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2009 Table of Contents GUIDE FOR THE CERT
6、IFICATION OF OFFSHORE MOORING CHAIN CONTENTS SECTION 1 General Requirements . 1 1 Scope 1 1.1 Application . 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 . 1 3.1 R3, R3S, R4, R4S, and R5 1 3.3 R4S and R5 . 1
7、3.5 Approval 2 5 Chain Manufacturer Approval . 2 5.1 Approval of Chain Manufacturers 2 5.3 Manufacturing 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 4 7 Approval of Qu
8、ality Systems at Chain Manufacturers 6 7.1 Quality Provision 6 7.3 Procedures for Obtaining Approval 6 7.5 Quality Assurance Certificate 7 7.7 Test Data and Documentation . 7 9 Approval of Steel Mills Rolled Bar and Plate for Chain and Accessories . 7 9.1 Bar and Plate Material for Chain and Accesso
9、ries, Including Pins 7 9.3 Approval Restrictions . 8 9.5 Chemical Composition . 8 9.7 Heat Treatment Sensitivity Study for Rolled Bars 8 9.9 Strain Aging, Temper Embrittlement, Hydrogen Embrittlement . 8 11 Accessory Manufacturer Approval 8 11.1 Approval of Forges and Foundries Accessories . 8 11.3
10、Approval Restrictions . 8 11.5 Forging Reduction Ratio 8 11.7 Chemical Composition . 9 11.9 Strain Aging, Temper Embrittlement, Hydrogen Embrittlement . 9 ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2009 v 11.11 Heat Treatment Sensitivity Study 9 11.13 CTOD Tests (Crack Tip Opening Dis
11、placement Tests) . 9 11.15 Furnace Calibration . 9 11.17 R4S and R5 Additional Requirements . 9 11.19 Manufacturing Process Approval . 10 11.21 Qualification Testing 10 13 Approval of Quality Systems at Accessory Manufacturers . 11 13.1 Quality Provision . 11 13.3 Procedures for Obtaining Approval .
12、 12 13.5 Quality Assurance Certificate 12 13.7 Test Data and Documentation . 13 TABLE 1 Mechanical Properties of Offshore Mooring Chain and Accessories . 2 SECTION 2 Material Requirements for Chain and Accessories . 14 1 Scope 14 3 Rolled Steel Bars 14 3.1 Steel Bar Manufacture . 14 3.3 Chemical Com
13、position 14 3.5 Mechanical Tests 14 3.7 Dimensional Tolerances 16 3.9 Nondestructive Examination and Repair . 17 3.11 Marking 17 3.13 Heat Treatment of Rolled Bars Intended for Accessory Pins . 17 5 Forged Steel . 17 5.1 Forged Steel Accessories 17 5.3 Chemical Composition 18 5.5 Heat Treatment . 18
14、 5.7 Mechanical Properties . 18 5.9 Mechanical Tests 18 5.11 Nondestructive Examination 19 5.13 Marking 19 7 Cast Steel . 19 7.1 Cast Steel Accessories . 19 7.3 Chemical Composition 19 7.5 Heat Treatment . 20 7.7 Mechanical Properties . 20 7.9 Mechanical Tests 20 7.11 Nondestructive Examination 20 7
15、.13 Marking 21 9 Materials for Studs 21 TABLE 1 Dimensional Tolerance of Bar Stock. 16 FIGURE 1 Sampling for Tension Specimens and Charpy V-Notch Specimens Steel Bars, Forgings and Castings . 16 vi ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2009 SECTION 3 Design and Manufacture of Cha
16、in and Accessories . 22 1 Design . 22 1.1 Design Details . 22 1.3 Stud Link Chain . 22 1.5 Kenter Shackles. 22 1.7 Special Subsea Mooring Connectors . 22 1.9 Ancillary Accessory Components 22 3 Chain Cable Manufacturing Process 22 3.1 Joining Shackles and Splice Links . 22 5 Chain Cable Manufacturin
17、g Process Records 23 5.1 Bar Heating 23 5.3 Flash Welding of Chain Cable . 23 5.5 Heat Treatment of Chain Cable . 23 7 Mechanical Properties 23 9 Proof and Breaking Test Loads 23 11 Freedom from Defects 23 13 Dimensions and Dimensional Tolerances 25 13.1 Link Shape and Proportion 25 13.3 Tolerances
18、Applicable to Chain Links 25 15 Stud Link Chain Welding of Studs . 27 15.1 Heat Treatment of Welded Studs. 27 15.3 Extent of Stud Weld . 27 15.5 Single Weld . 27 15.7 Weld Procedure Studs 28 15.9 Fillet Size . 28 15.11 Weld Quality 28 15.13 Stud Weld Inspection . 28 17 Connecting Common Links (Splic
19、e Links) 28 17.1 Procedure Approval . 28 17.3 Adjacent Links to Splice Links . 28 17.5 Testing and Inspection . 28 17.7 Identification 28 TABLE 1 Formulas for Proof and Break Test Loads, Weight, and 5-Link Length 24 FIGURE 1 Test Sample Locations in Link 24 FIGURE 2A Proportions, Dimensions and Tole
20、rances of Stud Link Common Link 26 FIGURE 2B Proportions, Dimensions and Tolerances of Studless Common Link 27 SECTION 4 Testing and Inspection of Finished Chain . 29 1 General . 29 3 Proof and Break Load Tests . 29 3.1 Proof Load Test . 29 3.3 Break Test Specimens . 29 ABSGUIDE FOR THE CERTIFICATIO
21、N OF OFFSHORE MOORING CHAIN .2009 vii 5 Dimensions and Dimensional Tolerances 30 5.1 Individual Link Measurement After Proof Load . 30 5.3 Five-Link Measurement After Proof Load . 30 7 Mechanical Tests on Completed Chain After Proof Load 30 7.1 Specified Tests 30 7.3 Test Frequency and Properties .
22、31 7.5 Frequency of Crown Impact Tests . 31 9 Nondestructive Examination After Proof Load Test . 31 9.1 Visual Inspection . 31 9.3 Nondestructive Examination General . 31 9.5 Magnetic Particle Inspection (MPI) 31 9.7 Ultrasonic Testing (UT) 31 11 Retest, Rejection and Repair Criteria . 32 11.1 Measu
23、rement of Five Links . 32 11.3 Replacement of Defective Links 32 11.5 Surface Defects . 32 11.7 Volumetric Defects 32 11.9 Geometrical or Tolerance Failure 32 11.11 Break Load Test Failure 32 11.13 Proof Load Test Failure . 33 11.15 Tensile Test Failure . 33 11.17 Charpy Test Failure . 33 13 Marking
24、 . 33 13.1 Locations for Marking of Chain 33 13.3 Markings 34 13.5 Chain Certificate 34 15 Manufacturers Documentation . 34 TABLE 1 Frequency of Break and Mechanical Tests 30 SECTION 5 Testing and Inspection of Accessories 35 1 General . 35 1.1 Accessory Manufacturing Process 35 1.3 Accessory Manufa
25、cturing Process Records 35 3 Proof and Break Load Tests . 35 3.1 Proof Load Test . 35 3.3 Break Load Test 35 3.5 Definition of a Batch 35 3.7 Accessories Subjected to Break Test 36 3.9 Over-Designed Accessories 36 5 Dimensions and Dimensional Tolerances 36 5.1 Dimensional Tolerances 36 7 Mechanical
26、Tests 36 7.1 Test Location of Forged Shackles . 36 7.3 Test Location of Cast Shackles . 36 7.5 Complex Geometry Accessories . 37 7.7 Individual Accessories or Small Batches . 37 viii ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2009 7.9 Definition of a Batch . 37 7.11 Test Location of P
27、ins . 37 9 Nondestructive Examination After Proof Load Test . 38 9.1 Visual and Surface Examination 38 9.3 Nondestructive Examination General . 38 9.5 Manufacturers Statement 38 11 Test Failures . 38 13 Marking and Certification 39 13.1 Marking 39 13.3 Certificates . 39 15 Documentation 39 FIGURE 1
28、Pin Heat Treatment Buffer 37 ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2009 1 Section 1: General Requirements SECTION 1 General Requirements 1 Scope 1.1 Application This Guide supersedes previous versions and ABS encourages its immediate application. Compliance with this edition is r
29、equired for offshore mooring chain and accessories with a date of purchase order of the materials on or after 1 July 2011. These requirements apply to the materials, design, manufacture, and testing of offshore mooring chain and accessories intended to be used for temporary and permanent application
30、s such as: mooring of mobile offshore units, mooring of floating production units, mooring of offshore loading systems, and mooring of gravity based structures during fabrication. 1.3 Mooring Equipment Mooring equipment covered is common stud and studless links, connecting common links (splice links
31、), enlarged links, end links, detachable connecting links (shackles), end shackles, double pinned H-type links, tri-plates and shackles, and H-links specifically designed for chain to wire/polyester rope connections. Mooring foundation shackles and anchor shackles for mooring are also to comply with
32、 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 intended for lon
33、g-term permanent mooring systems with pre-determined design life. 1.7 Chafing Chain Requirements for chafing chain for single point mooring arrangements are given in 3-5-1/17 of the ABS Rules for Building and Classing Steel Vessels. In addition, recognized industry standards such as OCIMF may be app
34、lied. 1.9 Special Subsea Mooring Connectors In the case 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 tho
35、se herein. 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 for mechanical properties. 3.3 R4S and R
36、5 Specifications for R4S and R5 are newly introduced into this Guide and therefore more detailed information regarding design, manufacture, testing, and specification details are to be submitted to ABS. Section 1 General Requirements 2 ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2009 3
37、.5 Approval Each grade of chain or accessory is to be individually approved. Approval for a higher grade does not constitute approval of a lower grade. Approved manufacturers will be included in the list of ABS Approved Manufacturers on the ABS website. The approval will indicate the Company, grade,
38、 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) Elongation in 5D minimum in percent Reduction of Area minimum in percent (3)Charpy V-
39、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 53 33 R4 580 (59, 84) 860 (87, 125) 12 (5) 50 (5) 20 50 36 R4S (4)700 (71, 101) 960 (9
40、8, 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 carried out at either 0C or minus 20C to meet the indicated values. It is not required
41、 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 and R5 chain and accessories. The target maximum hardness for R4S is HB330 and for R
42、5 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 requirements do not apply. 5 Chain Manufacturer Approval 5.1 Approval of Chain Manufacturers
43、Offshore mooring chains are to be manufactured only by works approved by ABS. For this purpose, approval tests 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 af
44、ter successful testing of the completed chain. The approval for each grade will normally be limited up to 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, a
45、nd not in lieu of, the witnessing of tests by a Surveyor as specified in Sections 2 to 5 of these requirements. Section 1 General Requirements ABSGUIDE FOR THE CERTIFICATION OF OFFSHORE MOORING CHAIN .2009 3 5.3 Manufacturing Process Approval Manufacturers are to submit for review and approval the s
46、equence of operations from receiving inspection to shipment, including details of the following manufacturing processes: i) Bar heating and bending, including method, temperatures, temperature control, recording, and in-process bar identification ii) Flash welding, including current, force, time, an
47、d dimensional variables, as well as control and recording of parameters iii) Flash removal, including method and inspection iv) Stud insertion (for stud link chain) method, imprint, and degree of plastic deformation after heat treatment. Stud welding (if applicable) v) Heat treatment, including furn
48、ace types, means of specifying, controlling and recording of temperature, chain speed and allowable limits, quenching bath and agitation, and cooling method after exit. Procedures, practices, temperatures and limits, heating and cooling rates. vi) Proof and break loading, including method, machine,
49、means of horizontal support (if applicable), method of measurement, and recording vii) Nondestructive examination procedures viii) The manufacturers surface quality requirement of mooring components ix) Connecting common link (splice link) procedures 5.5 CTOD Tests (Crack Tip Opening Displacement Tests) For initial approval, CTOD tests are to be carried out on the particular ABS mooring grade of material. CTOD tests are to be carried out in accordance with a recognized standard such as BS 7448 Parts 1 neither does it apply to licensees, subcont
