Safety Flash
Near-miss involving winch failure
Near-miss involving winch failure
- IMCA
- Safety Flash
- IMCA SF 01/03
- DivingInspection and MaintenanceMachinery and Equipment
- Mechanical failurePressure systems
- Inspection and maintenanceLifting operationsSaturation diving
- Diving bellValveWinch
- Emergency responseFunctional testing
- Marine industry
- Subsea
Summary
A saturation diving bell descended uncontrollably during recovery when trapped hydraulic pressure kept the winch brakes and counterbalance valve open. A cross-haul wire checked the descent and the bell was recovered. Investigation identified incorrect control-system plumbing; corrective work included a bleed line, separation of valve and brake, and valve replacement.
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: Saturation diving; sat diving.
Classifications: Diving bell; closed bell; wet bell.
Classifications: Valve; valves.
Classifications: Winch; winches.
Classifications: Emergency response; emergency preparedness.
Classifications: Functional testing; function test.
Classifications: Marine industry; shipping industry; maritime sector.
Classifications: Subsea; underwater worksite.
Summary
A hydraulic control-system fault caused a diving bell winch to descend uncontrollably during recovery.
IMCA SF 01/03. Themes: diving, inspection and maintenance, machinery and equipment.