Huisman completes fifth knuckle boom crane

Offshore staff

SCHIEDAM, the Netherlands -- Huisman is preparing to deliver a 250-metric ton (275-ton) knuckle boom crane to Subsea 7 for installation on the new multi-purpose construction vessel Seven Pacific. The crane will be used for offshore construction and subsea installations in water depths of up to 2,500 m (8,202 ft).

Previously, Huisman provided three 120-metric ton (132-ton) knuckle boom cranes for Hornbeck Offshore, Subsea 7, and EZRA and one 150-metric ton (165-ton) version for Technip. Another 150-metric ton crane, rated for water depths up to 3,000 m (9,842 ft), is under construction for Otto Candies.

The newest crane has an in-house developed, secondary controlled hydraulic drive system. This enables real-time active compensation of the heave movement of the crane tip, minimizing the load movement.

During heave compensation, energy can be stored in an accumulator to reduce the crane’s power consumption.

Other features of the new crane include three independent electro-hydraulic power units to provide a high level of redundancy. The plan is for the crane to remain operational with only one or two pump sets running.

09/10/2010