Investigation Report
Subsea Safety-Valve Leak Released Well Fluids Through Hydraulic Controls
10-22-2020 13:59 G09868 MC 778 Pollution
- BSEE
- Investigation Report
- Unknown
- Environmental protectionLoss of containmentMechanical failure
- Pressure testingROV operations
- Gas detectorValve
- Competence and trainingFunctional testingEnergy and process isolation
- Upstream oil and gas
- Offshore installationSubsea
Summary
BSEE investigates a Thunder Horse shutdown followed by discovery of a subsea safety-valve leak. Failed rod piston seals allowed well fluids into hydraulic controls and subsea venting, with an estimated 3–50 barrels released. The report examines ROV inspections, sampling and valve tests, and recommends operator training and hurricane-related precautions.
Classifications: Environmental protection; environmental safety; pollution prevention.
Classifications: Loss of containment; containment loss.
Classifications: Mechanical failure; equipment failure.
Classifications: Pressure testing; hydrostatic testing; pneumatic testing.
Classifications: ROV operations; remotely operated vehicle operations.
Classifications: Gas detector; gas monitor; gas detection instrument.
Classifications: Valve; valves.
Classifications: Competence and training; competency assurance; safety training.
Classifications: Functional testing; function test.
Classifications: Energy and process isolation; isolation; energy isolation.
Classifications: Upstream oil and gas; oil and gas extraction; upstream petroleum.
Classifications: Offshore installation; offshore platform; offshore rig.
Classifications: Subsea; underwater worksite.