NZ630561A - Marine lifting vessel - Google Patents

Abstract

A marine lifting vessel or catamaran having two buoyant hulls each provided with static buoyancy, where the catamaran has a rigid working deck 130 having a top, an underneath, two sides, a bow aspect and a stern aspect. The deck 130 is movably and symmetrically supported along each side from the adjacent hull by a plurality of intermediate beams arranged in a parallel array thereby indirectly securing one hull to the other. Each intermediate beam is comprised of two beams ( a “hull beam” and a “deck beam”), pivotally joined together at their adjacent ends and having a substantially horizontal axis of rotation, thereby forming a lifting joint, the far end of each beam being fixedly attached to the hull and to the deck 130 respectively. Each joint shares a common axis of rotation with the joints of the other intermediate beams. The catamaran includes joint control or actuator means to forcibly change the angle between the hull beam and the deck beam at the lifting joint. All joint control means are under the co-ordinated control of a controller, so that, when in use, a height of the rigid deck 130 in relation to a water line can be altered by the controller by forcibly causing the angles of a plurality of the joints to change thereby either lifting the deck 130 higher above the water line, or lowering the deck 130 to or below the water line.