Chain hoist failure resulting in a serious near miss

What happened?

During maintenance of a vessel’s main engine there was a requirement to remove the charge air cooler weighing 400kg. 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 500kg) 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.

What were the findings?

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.

What actions were taken by our member?

• Full inventory made of all powered hoists (pneumatic and electric) to include both chain hoists and wire hoists and not restricted to permanently installed units;
• Additional relevant maintenance scope added to planned maintenance scopes for all these devices;
• Powered hoists fitted with overload devices should be set at working load limit +10% and checked annually as part of the planned maintenance regime.

Members may wish to refer to:

• Failure of bell winch clutch coupling during bell recovery