World's largest offshore mast crane installed

Huisman has installed the world's largest offshore mast crane onboard the heavy lift ship Seven Borealis, says the company.

The Netherlands-based lifting, drilling and subsea specialist said the four-day installation of the 5,000 tonne lifting capacity crane was its heaviest and most complex project to date.

BigLift's Happy Buccaneer carried the mast sections from Huisman's production facility in Zhangzhou, China to the Sembawang Shipyard, Singapore. There the four sections were installed in the following sequence: mast base, slewing section, boom and mast. The reeving and commissioning of the crane are now underway.

Apart from the two 2,500 tonne main hoisting blocks, the crane has a 1,200 tonne auxiliary hoist equipped with a heave compensator capable of storing up to 6,000 m of 109 mm diameter hoisting wire. The tip of the fly jib has an additional 110 tonne auxiliary hoist.

Further components include four load tuggers and an additional five block tuggers. The installed electro motor power is about 15 MW, with another 1.6 MW hydraulically. The slew bearing is custom designed and built by Huisman.

The company has started the fabrication of a similar mast crane with a revolving lift capacity of 4,000 tonnes, planned for delivery in 2012.