Stored pressure release near-miss: Small part expelled from hydraulic winch

  • Safety Flash
  • Published on 4 July 2016
  • Generated on 23 July 2026
  • IMCA SF 18/16
  • 2 minute read

A Member has reported an incident in which a part was expelled from a hydraulic system under pressure, causing a leak of hydraulic oil. 

What happened?

The incident occurred when the hydraulics were activated to turn the winch drum to install a new wire rope. There was a loud bang from the hydraulic pack as a sensor was forced out of the unit. The sensor hit the bulkhead to the right. Approximately 2 litres of hydraulic oil was also expelled from the winch onto the deck and bulkhead.

Hydraulic system

Our member’s findings were as follows:

  • Company safe system of work had not been followed – there had been no permission or sanction to test this equipment.
  • The hydraulic system had not been commissioned properly. The hydraulic hoses had been fitted the wrong way around.
  • The handover between technicians following crew change had not identified these issues.

Our member's recommendations were:

  • Improve communication between crews at handover especially at crew change.
  • Formal ‘sanction to test’ should be completed before it is handed over to the responsible person in charge.
  • Suitable and sufficient risk assessment and pre-use check list to be created and used for this work and equipment.
  • Status and condition of equipment should be clearly defined before planned maintenance is carried out.

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