Core Technical Indicators and Surface Treatment Methods for Marine Anchor Chains and Offshore Mooring Chains

1. Core Definition and Application Boundaries

2. Core Technical Indicators

2.1 General Mandatory Compliance Indicators (One-Vote Veto, Mandatory for Classification Inspection)

1. Standard Compliance
   • Marine anchor chains: Must comply with ISO 1704:2022 Ships and marine technology — Stud-link anchor chains, GB/T 549-2017 Electric Welded Anchor Chains, as well as corresponding classification society rules (such as CCS Rules for Classification and Construction of Sea-Going Steel Ships, DNV-OS-E301, etc.).
   • Offshore mooring chains: Must comply with API Spec 2F Specification for Mooring Chain, ISO 20438:2017 Ships and marine technology — Mooring chains, as well as special requirements including DNV-OS-E303 and CCS Specification for Offshore Mooring Systems.
   
   
2. Classification Society Certification and Traceability
   • Must hold a valid Type Approval (TA) Certificate issued by the classification society where the target facility is classed (CCS, DNV, LR, ABS, BV, NK, etc.). Each batch of products shall be accompanied by traceable material reports, mechanical property reports and non-destructive testing reports.
   • Each link must be marked with permanent steel stamping, clearly indicating grade, specification, production batch number, manufacturer code, and classification society mark, to ensure full life cycle traceability.
   
   
3. Mandatory Structural Requirements
   • Marine anchor chains: The mainstream type is stud-link chain, with a cross stud inside the link, which can increase the breaking strength by about 15% and prevent link deformation and twisting. Studless chains are only used for small vessels.
   • Offshore mooring chains: Divided into stud-link and studless chains. Large-size chains for deep water mostly adopt studless chains to adapt to the dynamic load characteristics of the mooring system.
   
   

2.2 Material Chemical Composition Indicators