Offshore role for hoist

Seawater pumps are an integral part of the working environment within oil and gas offshore structures. Seawater itself is utilised for general cooling of on-site production activities, while also providing a major safety dousing factor in the event of fire or leakage occurring in the hazardous and potentially explosive offshore atmospheric conditions.

The maintenance, repair or even total replacement of the associated pumps and pipework on the rig is undertaken by Gerritsen On- & Offshore Services BV. A four man team undertook the dismantling of one pump and pipework assembly out of the three similar installations in the pump area.

To handle the lifting and temporary storage of the components involved, a 20m lift from sea level to an upper storage area was required. To undertake this task an air operated hoist (model EH20) was used. This offered a SWL capacity of 20t, providing intrinsically safe performance within such hazardous environments with appropriate Ex safety ratings.

It was provided with a chain drop lift capacity of 12m, and included a similar length umbilical for the hoist hand controller with the operator located at the lower deck. The EH model JDN hoist was mounted on an overhead rail which provided the necessary lateral movements to facilitate individual load laydowns at a temporary storage area prior to undertaking the reassembly task.

The pump riser pipework comprised a total of eight x 3.5m x 16in diameter pipes, which were disconnected to provide two connected pipes per lift. The pump located at the bottom of the pipework was approximately 8m in length and weighed some 9250kg. 

The EH20 is part of the JDN monorail air hoist range designed for handling heavy loads while operating within confined spaces. A total of 11 models are available, with lift capacities ranging from 10 to 100t. These hoists are insensitive to humidity and dust, while operating within a temperature range of -20 to 70°C.