Active hold down system for jack-up drilling unit

摘要

A cantilever beam of a jack-up unit is provided with constant force restraining members mounted on a deck of a jack-up unit forward from conventional hold-down cantilever beam clamp. A modified cantilever beam end plate engages a first end of constant force restraining member, which may be a hydraulic cylinder, with the second end of the hydraulic cylinder secured to movable padeye, which is releasably secured to the deck of the jack-up unit. If desired a fixed foundation may be secured to the deck to reinforce the area of attachment of a padeye to the deck. To allow extension of the cantilever beam even farther to a drill well, an extension member may be attached to the end plate between a free end of the end plate and the hydraulic cylinders.