Chain hoist failure resulting in a serious near miss

During maintenance of a vessel’s main engine there was a requirement to remove the charge air cooler weighing 400 kg.

The third-party contractor who was tasked with the maintenance job was in the process of lifting the item when the (electric) chain hoist failed, resulting in the load dropping two metres to the engine room deck plating.

The chain hoist used for the vertical lift (SWL 500 kg) was permanently installed on an engine room running beam located specifically to facilitate this type of operation.

After the incident, the hoist was quarantined and analysed by a third-party specialist company in order to establish the cause of failure.

The inspection and maintenance regime for the hoist was within date but was considered inadequate as it only involved a visual inspection and function test (without load).

The unit was infrequently used and was not subjected to internal inspection; this allowed the internal braking mechanisms to suffer corrosion, and this prevented the braking function operating properly when under load.

The above resulted in the clutch failing to hold the load, lowering the charge air cooler to the engine room deck plating in an uncontrolled and rapid manner.

Good planning and rigging practice were observed by the lifting team, personnel were in ‘safe zones’ during the lift and not in the line of fire. Slight damage to the deck plating was observed.