KULLUK - An Ice Breaking Drilling Barge

This paper describes the design and construction features of the first purpose-built floating drilling unit for arctic waters. It was designed by Earl and Wright - Lavalin for Gulf Canada Resources Inc., Beaufort Sea Drilling System Division, built by Mitsui Engineering and Shipbuilding Company, and delivered on April 2, 1983. The owner is BeauDril Limited Partnership. It is presently en route to the Beaufort Sea, where it is scheduled to commence drilling in the fall of 1983. The unit is nearly circular in plan, consisting of 24 segments (and thus 24 sides). Its conical shaped hull is designed to deflect ice downward, breaking it in flexure. The hull is extensively compartmented, with a continuous-void double bottom against the sea to allow easy detection of damage and prevent pollution of the sea in case damage occurs. A special steel specification was developed for the C service temperature. A 12-point mooring system was designed to resist ice forces from 4 feet of ice moving in any direction. If the ice forces become too large, the unit can be disconnected from its moorings and move with the ice.