Dual-derrick ice-worthy jack-up drilling unit

摘要

The invention relates to a jack-up rig. The inventive rig would work like a conventional jack-up rig while in open water with the hull jacked up out of the water. However, in the event of ice conditions, the hull is lowered into the water into an ice defensive configuration. The hull is specifically shaped with a lower portion that is an ice-bending surface to bend and break up ice that comes in contact with the hull while in the ice defensive configuration. Furthermore, the jack-up rig comprises at least two derricks.