The crane uses a series of special sheaves tofeed the rope out from a fibre rope system mounted under the deck . The capacity of cranes using conventional ropes is limited in deep sea applications by the weight of the rope. On active heave compensated (AHC) cranes such as this, the AHC system must spool rope in and out at up to 2m per second (120m min). The weight of steel wire rope puts extra strain on the AHC system, limiting the length of rope it can work with. The new rope in this crane is neutrally buoyant, meaning it adds no load to the crane, regardless of the depth it is operating at.
MacGregor will deliver the crane in January, to be installed on the subsea vessel Havila Phoenix. The 250-tonne Hydramarine active heave-compensated (AHC) offshore crane is designed with a 250t/3,000m single-line winch and is prepared for a 250t single-line fibre rope.
“MacGregor’s technology for handling lightweight fibre rope rather than traditional steel wire rope offers several advantages that will meet the ever-increasing demands of the offshore industry as operators move further into deeper and more remote territories,” says Øystein Bondevik, sales director in MacGregor’s offshore division. “For example, due to the neutralisation of the weight of the fibre rope in the water, much heavier loads can be handled without strain to the crane at unlimited depths. Consequently, overall safety is improved due to the lighter equipment, which can still carry out heavy work operations.”
