DNVGL-OS-E302 Offshore Mooring Chain

OFFSHORE STANDARDSDNVGL-OS-E302Edition July 2018Offshore mooring chainThe electronic pdf version of this document, available free of chargefrom http://www.dnvgl.com, is the officially binding version.DNV GL AS

FOREWORDDNV GL offshore standards contain technical requirements, principles and acceptance criteriarelated to classification of offshore units. DNV GL AS July 2018Any comments may be sent by e-mail to rules@dnvgl.comThis service document has been prepared based on available knowledge, technology and/or information at the time of issuance of thisdocument. The use of this document by others than DNV GL is at the user's sole risk. DNV GL does not accept any liability or responsibilityfor loss or damages resulting from any use of this document.

This document supersedes the July 2015 edition of DNVGL-OS-E302.Changes in this document are highlighted in red colour. However, if the changes involve a whole chapter,section or subsection, normally only the title will be in red colour.Changes July 2018TopicAlignment to revised IACSW22 on Offshore MooringChain (rev 6 June 2016)ReferenceDescriptionCh.2 Sec.1 [1.2.2]Updated clause, clarification on samples location.Ch.2 Sec.1 [1.5.3]Updated clause, clarification on charpy samples.Ch.2 Sec.1 [1.6.2]Updated clause, included ISO 9934 as acceptable NDTstandard.Ch.2 Sec.1 [2.8.1]Updated clause, possibility for magnetic flux leakage.Ch.2 Sec.1 [2.9.2]New clause, clarification on welding repair.Ch.2 Sec.2 [2.3.2]Updated clause, clarification on control parameters.Ch.2 Sec.2 [2.5.3]Updated clause, doc req change.Ch.2 Sec.2 [2.6.2]Updated clause, new approach.Ch.2 Sec.2 [2.7.5]Introduction of R6 materialgradeCh.2 Sec.2 [2.9.4]Updated clause, small change to the tolerances.Ch.2 Sec.2 [3.5.2]Updated clause, clarification.Ch.2 Sec.2 [3.5.3]Updated clause, new requirement.Ch.2 Sec.2 Table 1and 3New R6 mechanical properties and proof load/break load testvalues.Ch.2 Sec.1 Table 1New R6 mechanical properties.Editorial correctionsIn addition to the above stated changes, editorial corrections may have been made.Offshore standards, DNVGL-OS-E302. Edition July 2018Offshore mooring chainDNV GL ASPage 3Changes - currentCHANGES – CURRENT

Changes – current. 3Chapter 1 Introduction. 5Section 1 Introduction. 51 General.52 Normative references.63 Definitions. 7Chapter 2 Technical provisions. 9Section 1 Materials. 91 General requirements. 92 Rolled steel bars. 133 Steel forgings.154 Steel castings.165 Materials for studs. 18Section 2 Mooring chain cables and accessories. 201 General requirements. 202 Mooring chain. 203 Chain accessories.27Chapter 3 Certification and classification.32Section 1 Certification and classification - requirements.321 General.322 Certification and classification requirements. 33Appendix A Scope of survey for mooring chain. 36Appendix B Scope of survey for mooring chainaccessories. 38Changes – historic.40Offshore standards, DNVGL-OS-E302. Edition July 2018Offshore mooring chainDNV GL ASPage 4ContentsCONTENTS

Chapter 1 Section 1CHAPTER 1 INTRODUCTIONSECTION 1 INTRODUCTION1 General1.1 IntroductionThis offshore standard contains criteria, technical requirements and guidance on materials, design,manufacture and testing of offshore mooring chain and accessories.1.2 ObjectiveThe objectives of this standard are to:— provide an internationally acceptable standard of safety by defining minimum requirements for offshoremooring chain and accessories— serve as a contractual reference document between manufacturers and purchasers— serve as a guideline for designers, suppliers, purchasers and regulators— specify procedures and requirements for offshore mooring chain and accessories subject to DNV GLcertification and classification.1.3 Scope and application1.3.1 The standard has been written for general world-wide application. Governmental regulations mayinclude requirements in excess of the provisions by this standard depending on the size, type, location andintended service of the offshore unit or installation.1.3.2 The mooring chain and accessories specified herein are intended for position mooring applicationssuch as: mooring of mobile offshore units, mooring of floating production units, mooring of offshore loadingsystems, and mooring of gravity base structures during fabrication.1.3.3 Mooring chain links covered are common stud links and common stud less links, connecting commonlinks (splice links), enlarged links and end links.1.3.4 Mooring chain accessories covered are detachable connecting links (shackles), connecting plates(triplates etc), end (anchor) shackles, swivels and swivel shackles.1.4 StructureThis standard is divided into three main chapters:— Chapter 1: Sec.1 with general information, scope, definitions and references— Chapter 2: Sec.1 and Sec.2 with technical provisions for materials and chain cables— Chapter 3: Sec.1 specific procedures and requirements applicable for certification and classification ofmaterials and chain cables in accordance with this standard. Also, requirements to design verification aregiven.— App.A and App.B list the scope of survey for the mooring chain respectively mooring chain accessories.Offshore standards, DNVGL-OS-E302. Edition July 2018Offshore mooring chainDNV GL ASPage 5

2.1 General2.1.1 The standards in Table 1 include provisions which, through reference in this text, constitute provisionsof this offshore standard. Latest issue of the standards shall be used unless otherwise agreed.2.1.2 Other recognised standards may be used provided it can be demonstrated that these meet or exceedthe requirements of the standards in Table 1.2.1.3 Any deviations, exceptions and modifications to the design codes and standards shall be documentedand agreed between the supplier, purchaser and verifier, as applicable.2.2 Reference documentsApplicable reference documents are given in Table 1.Table 1 Normative referencesNo.TitleAPI Spec 2FSpecification for mooring chainAPI Spec 6ASpecification for Wellhead and Christmas Tree Equipment, Twentieth Edition (ISO 10423:2009Modification)ASME BPVC IXBoiler and Pressure Vessel Code - Section IX: Welding and Brazing QualificationsASNTSNT-TC-1A American Society for Non-destructive Testing – Recommended PracticeASTM A255Standard Test Methods for Determining Hardenability of SteelASTM A275Standard Practice for Magnetic Particle Examination of Steel ForgingsASTM A388Standard Practice for Ultrasonic Examination of Steel ForgingsASTM A488Standard Practice for Steel Castings, Welding, Qualifications of Procedures and PersonnelASTM A609Standard Practice for Castings, Carbon, Low-Alloy and Martensitic Stainless Steel, UltrasonicExamination ThereofASTM A991Standard Test Method for Conducting Temperature Uniformity Surveys of Furnaces Used to HeatTreat Steel ProductsASTM E112Standard Test Methods for Determining Average Grain SizeASTM E381Standard Method of Macro-etch Testing Steel Bars, Billets, Blooms and ForgingsASTM E587Practice for Ultrasonic Angle-Beam Examination by the Contact TestingASTM E709Standard Guide for Magnetic Particle TestingASTM E1417Standard Practice for Liquid Penetrant TestingASTM E1444Standard Practice for Magnetic Particle TestingDNVGL-OS-B101Metallic materialsDNVGL-CP-0237Offshore mooring chain and accessoriesOffshore standards, DNVGL-OS-E302. Edition July 2018Offshore mooring chainDNV GL ASPage 6Chapter 1 Section 12 Normative references

TitleEN 287-6Qualification test of welders - Fusion welding - Part 6: Cast ironEN 10204Metallic products - Types of inspection documentsEN 10228-1/3Non-destructive testing of steel forgingsISO 4967Steel – Determination of content of non-metallic inclusions – Micrographic method using standarddiagramsISO 1704Ships and marine technology – Stud-link anchor chainsISO 8501-1Preparation of steel substrates before application of paints and related products - Visualassessment of surface cleanliness - Part 1: Rust grades and preparation grades of uncoated steelsubstrates and of steel substrates after overall removal of previous coatingsISO 9606 seriesQualification testing of welders - Fusion weldingISO 9712Non-destructive testing - Qualification and certification of NDT personnelISO 10423Petroleum and natural gas industries - Drilling and production equipment - Wellhead andchristmas tree equipmentISO 13588Non-destructive testing of welds - Ultrasonic testing - Use of automated phased array technologyISO 15549Non-destructive testing – Eddy current testing – General principlesISO 15614 seriesSpecification and qualification of welding procedures for metallic materials - Welding proceduretest3 Definitions3.1 Verbal formsTable 2 Verbal formsTermDefinitionshallverbal form used to indicate requirements strictly to be followed in order to conform to thedocumentshouldverbal form used to indicate that among several possibilities one is recommended as particularlysuitable, without mentioning or excluding others, or that a certain course of action is preferredbut not necessarily required.mayverbal form used to indicate a course of action permissible within the limits of the document.Agreement,agreed or byagreementunless otherwise indicated, agreed in writing between manufacturer and purchaser or DNV GLwhere DNV GL is certifying the productOffshore standards, DNVGL-OS-E302. Edition July 2018Offshore mooring chainDNV GL ASPage 7Chapter 1 Section 1No.

Table 3 TermsTermDefinitionpurchaserthe owner or another party acting on his behalf, who is responsible for procuring materials,components or services intended for the design, fabrication or modification of a unit or installationmanufacturerthe party who is contracted to be responsible for planning, execution and documentation ofmanufacturingOffshore standards, DNVGL-OS-E302. Edition July 2018Offshore mooring chainDNV GL ASPage 8Chapter 1 Section 13.2 Terms