CAPE TOWN-based Petrel Engineering, part of the Elgin Group of companies, designed, manufactured, installed and commissioned a heavy duty barge launch and recovery crane for the island of Tristan da Cunha.

Petrel became involved in the project following an inquiry from Ivor Mumford of The Apple Group of companies, after the original tracked mobile crane used to launch the barge which services the island, was was damaged in April last year.

The crane is an electro-hydraulic fixed gantry type crane with dual crawl beams, each crawl beam able to handle a safe working load of 10 ton and controlled by means of a single control station.

Both crawl hoists are used in a tandem lift to launch and recover the barge which has an operational mass of 17 tons.

20' ISO containers can also be handled by means of a purpose built spreader beam and smaller cargo items handled by each crawl hoist independently.

The span and overall length of the crawl beams are 8m and 19m respectively. The height of lift is 5.2 m and the overall height of the gantry 10.8m

A 90kW electro-hydraulic power pack drives the crane and is housed in a modified shipping container.

The crane had to be designed in such a way as to be easily transported to and erected on the island.

A purpose built powered pontoon was sourced and supplied by the Apple Group in order to transport the crane components, some of which were 14m in length and 4 tons in mass, from the supply vessel to the shallow draught Calshot harbour of the island.

Petrel’s team on the island were assisted by specialist riggers from Target Rigging, under the leadership of Neill Rodgers.

Apple site and project’s Charl Moolman was responsible for the project management of the installation of the gantry crane on the island.

The impressive new crane was commissioned last month.