Global hydraulics leader Enerpac has developed an advanced handling and adjustment device for the world’s largest offshore gantry crane in Reunion Island.

The handling device, which has just completed testing on the Zourite jack-up barge, will be used to lift and lower the piers bases onto a level gravel surface on the seabed, and for making adjustments to the base vertically and horizontally.

The pier positioning and handling system, which utilises technology available throughout South East Asia, is lifted and controlled by Enerpac’s Over Head Travel Crane (OHTC), the world’s largest offshore overhead travel crane. The OHTC comprises two pairs of lifting beams, with an overall width of 30m, and a lifting capacity of 4,800 tonnes for lifting, moving and lowering the concrete blocks for the offshore highway.

“Global success stories provide inspiration to local operations,” says Enerpac SE Asia Integrated Solutions Manager, Mr Maxim Lee.

“Being a global company, we can share knowledge and experience throughout the Enerpac network, which spans 20 countries,” he said.

Reunion Island Highway

The French consortium Bouygues Travaux Publics, VINCI Construction Grands Projets, Dodin Campenon Bernard and Demathieu Bard Construction are constructing a 5,400 m bridge for a new offshore highway in Reunion Island, located East of Madagascar in the Indian Ocean. The new offshore highway (Route du Littoral) will connect Saint Denis – the administrative capital of La Réunion – with La Possession. It replaces the existing coastal road, which is exposed to falling rocks and flooding from swells and tropical storms.

Enerpac Over Head Travel Crane (OHTC)

The Over Head Travel Crane (OHTC) comprises two pairs of lifting beams, with an overall width of 30m, and a lifting capacity of 4,800 tonnes for lifting, moving and lowering the concrete blocks for the offshore highway. The crane is classified as A5 for the structure classification and M5 for the mechanism classification and designed to operate in tropical marine conditions (IP66). Design and testing conforms to Bureau Veritas code for Offshore Units.

The Enerpac OHTC will be used on the Zourite jack-up barge. Lifting and lowering is accomplished with a reeved winch system, based on eight grooved drum winches. Longitudinal travelling of the gantry uses a trolley arrangement comprising two trolleys per lifting beam. Each trolley is propelled with hydraulic drive motors and planetary gearboxes. The wheels run on two parallel rails bolted onto the barge’s runway beams. Side shifting of the gantry hoists in a continuous movement is achieved using long stroke cylinders.

OHTC testing has been conducted on one of the pairs of beams and included lifting 1100Te blocks, synchronized lifting of the block with a hook from each beam, and checking the crane’s positioning, lifting / lowering accuracy to 1 millimeter.