Investigation Report
Crown Motion Compensator Bracket Fell Following Drill-Line Slipping and Cutting
09-21-2020 21:00 G18745 WR 634 Other - Lifting - CMC
- BSEE
- Investigation Report
- Unknown
- Dropped objectsFunctional safetyMechanical failurePressure systems
- Inspection and maintenanceLifting operations
- Valve
- Competence and trainingFunctional testingOperating and work procedures
- Upstream oil and gas
Summary
Investigation of a crown motion compensator incident following drill-line slipping and cutting on Deepwater Conqueror. Rapid cylinder retraction sheared bumper assembly bolts, allowing a bracket to fall to the drill floor. Findings identify procedural non-compliance and a software logic error; subsequent measures included revised procedures, training and tested software changes. No injuries were reported.
Classifications: Dropped objects; falling objects; DROPS.
Classifications: Functional safety; safety instrumented systems; SIS.
Classifications: Mechanical failure; equipment failure.
Classifications: Pressure systems; stored pressure; pressurised systems; pressurized systems.
Classifications: Inspection and maintenance; asset inspection; equipment maintenance.
Classifications: Lifting operations; load lifting; hoisting.
Classifications: Valve; valves.
Classifications: Competence and training; competency assurance; safety training.
Classifications: Functional testing; function test.
Classifications: Operating and work procedures.
Classifications: Upstream oil and gas; oil and gas extraction; upstream petroleum.