Investigation Report
Mooring Chain Failure on Spar During Production
07-18-2021 09:30 G10380 AC 25 Incident >$25K #4 mooring line failure
- BSEE
- Investigation Report
- Unknown
- Mechanical failureStructural and asset integrity
- Inspection and maintenance
- Mooring lines
- Upstream oil and gas
- Offshore installation
Summary
Investigation of a mooring chain failure on the Diana Hoover Spar during production. Examination linked crown and weld fractures to hydrogen embrittlement and deficient material properties, likely associated with improper heat treatment. ROV surveys and hardness testing assessed remaining chains; modelling supported continued production with eleven lines.
Classifications: Mechanical failure; equipment failure.
Classifications: Structural and asset integrity; asset integrity; structural integrity.
Classifications: Inspection and maintenance; asset inspection; equipment maintenance.
Classifications: Mooring lines; mooring rope; mooring wire.
Classifications: Upstream oil and gas; oil and gas extraction; upstream petroleum.
Classifications: Offshore installation; offshore platform; offshore rig.