Offshore and heavy lift crane manufacturer Huisman has unveiled a patented Rope Luffing Knuckle Boom Crane.
The new active heave compensated cranes provide combine the benefits of a normal luffing crane with a traditional knuckle boom crane. As such it offers a high lifting height and good capacities at outreach. By incorporating a knuckle in the design it is possible to reduce the pendulum of the hook and, if extended, it can allow for high lifting heights. Furthermore, the boom of the crane can be stored vertically saving valuable deck space.
The main hoisting system comprises a traction and storage winch system and a separate heave compensation system. This means both lifting/lowering and heave compensation can occur simultaneously with no performance interdependency, resulting in a better overall system performance and increased safety, according to the manufacturer. A failure in main hoisting system will not affect the heave compensator or the other way around.
Other features include a patented anti-twist device and electric drive system. Because the crane is fully electrically driven, the power consumption, noise levels, and the number of components are reduced, making the crane more reliable than hydraulically driven cranes. It also helps reduce maintenance and operational costs.
The capacities of the new cranes range from 400 to 1,200 tonnes with the ability to cope with up to 5,000 metres of water depth. The first crane of this type to be built will be a 900 tonne unit for Subsea 7’s ‘Seven Arctic’, scheduled for delivery in 2016.