Air operated monorail hoists for offshore rig application

Four JD Neuhaus EH50 air operated monorail hoists have been supplied and mounted by Westcon Løfteteknikk AS of Bergen to the Maersk offshore rig Guardian.

These products have been specified for the synchronised lifting and handling of a 15,000psi BOP (blowout preventer) unit before and after drilling operations. Two hoists are each mounted on twin parallel overhead rails, with each hoist providing 50t load and 20m lift capacities for between deck operations.

Removable connector bars have also been supplied for fitting between paired hoists on the individual rails to maintain a fixed working distance of 4,060mm between the load hook centres. With the two sets of hoists operating together, a combined lift capacity of 200t is made available.

The minimum horizontal travel distance of the trolleys with the connector bars fitted is 14.81m. The maximum available free travel without the connector bars in place is 18m, with the travel distance limited by pneumatic end switches mounted on the hoist trolleys.

Synchronised operation of all linear movement and lifting operations of individual, paired or all the four hoists when used in conjunction, is provided with the F type multi-function pendant controllers also supplied by JDN. These tough, ergonomically designed controllers are suitable for outdoor, heavy-duty operations that can be experienced offshore.

A main air emergency stop together with load monitoring device is incorporated in the controllers. The two overhead beams are 23m in length and also carry twin energy chain power supplies, with each power chain comprising two air supply hoses.

A complete offshore documentation package was supplied together with all hoists having JDN’s full protection kit for offshore corrosion protection which includes trolley wheel bearings and threaded bolt ends and nuts fitted with grease packed covers, hoists fitted with special-design galvanised chain containers with stainless steel suspension chains and hoists finished with a JDN four layer marine paint, top coat.

The hoists provided are part of a range of well-proven JDN monorail hoists with individual lift capacities from 10 to 115t. Westcon Løfteteknikk AS is an authorised Norwegian sole importer of JD Neuhaus lifting and handling equipment.