Safety Flash
Failure of winch brake on air diving bell system
Failure of winch brake on air diving bell system
- IMCA
- Safety Flash
- IMCA SF 08/01
- DivingInspection and MaintenanceLifting OperationsMachinery and Equipment
- Material fatigueMechanical failure
- Diving operationsInspection and maintenance
- Diving bellWinch
- Preventive maintenance
- Marine industry
- Vessel
Summary
An unmanned wet diving bell fell 6 m through air and a further 15 m through water onto its clump weight, without injury. Investigation identified fatigue fracture following hinge-pin seizure from inadequate lubrication, compounded by hydraulic pressure decay. The company planned winch checks and advised regular brake maintenance.
Classifications: Material fatigue; metal fatigue.
Classifications: Mechanical failure; equipment failure.
Classifications: Diving operations; diving; commercial diving.
Classifications: Inspection and maintenance; asset inspection; equipment maintenance.
Classifications: Diving bell; closed bell; wet bell.
Classifications: Winch; winches.
Classifications: Preventive maintenance; preventative maintenance; planned maintenance.
Classifications: Marine industry; shipping industry; maritime sector.
Classifications: Vessel; aboard ship; onboard vessel.
Summary
A poorly maintained secondary brake failed, allowing an unmanned diving bell to free-fall into the water.
IMCA SF 08/01. Themes: diving, inspection and maintenance, lifting operations, machinery and equipment.