Hoists facilitate crane repairs

The crane was operating at 40m above sea level and provided a lift capacity of 20t. Replacing the broken engine, which weighed about 1750kg, presented a logistical challenge. The diesel engine replacement operation was successfully undertaken by the Gerritsen On- & Offshore Services.

As the replacement engine was too large and heavy to be ferried by helicopter, a lifting device was needed that was explosion-proof, lightweight and easy to handle. The lifting device was sourced from the J D Neuhaus range of air operated hoists available in the Gerritsen rental fleet. It was a Profi 2TI model with a lift capacity of 2t. This model is available as standard with a 3m lift and overall weight of 110kg including the control system. It was easily modified to provide the 40m lift required on site, involving an additional weight for the twin chain hoist mechanism at about 2kg/m run.

With the replacement engine and its lifting equipment being transported by a supply vessel (16 hours sea time), provision was required for a further primary lifting unit to handle the Profi 2 TI hoist and its 40m drop of twin chains used for the lifting operation. Once again, equipment that was light enough to be delivered to site by helicopter was selected from the Gerritsen rental fleet.

This was a J D Neuhaus air operated Mini hoist, providing 980kg lift capacity to handle the larger and more powerful Profi hoist and its chains. The Mini hoist plus an appropriate beam clamp for the hoist suspension support was helicoptered in (30 minutes air time) and mounted ready for the primary lift operation of the Profi hoist and chains using a big bag container. The more powerful Profi unit was then used to replace the Mini hoist, using the same beam clamp installation. The Profi hoist with a 2t lifting capacity was then used to undertake the more difficult lift and location of the replacement diesel engine using a sling assembly. The work was undertaken with one rig personnel for safety inspection, together with one rigger and three scaffolders.

The J D Neuhaus range of air operated hoists are universally deployable, incorporating explosion protection and are suitable for use in hazardous areas. The Mini series is available in load capacities of 125, 250, 500 and 980kg together with a manipulator version providing for one handed operation of lift, lower and hoist traverse operations. These products are explosion protected and feature an Ex classification of Ex II 3 GD IIA T4.

The Profi series hoists offer a more rugged build quality for heavier duty operations, and can be supplied with lift capacities from 250kg to 100t. 100% duty rating and unlimited duty cycles are provided as standard, ensuring no down time and low maintenance requirements, They are supplied as standard with classification Ex II 2 GD IIA T4 / II 3 GD IIB T4, with increased spark protection to Ex II 2 GD IIB T4 and for explosion group IIC : Ex II 2 GD IIC T4. These products are insensitive to dust, humidity and temperatures ranging from -20 to +70°C. They also provide infinitely variable speed controls for the precise positioning of loads.