The offshore unit and method of installing wellhead platform using the offshore unit.

摘要

There is disclosed an offshore unit (10, 60, 62, 64, 58, 70) which includes hull (22) and/or deck frame (52), a mat (14) attached to at least one connecting leg (16) or a spud can (50) attached to each of at least one connecting leg or lower hull (18) attached to at least one connecting means (66), a wellhead deck (24) is removeably attached to the hull (12) and/or deck frame (52) and a sub-sea clamp in conjunction with a caisson (20) or a sub-sea conductor frame (32) removeably attached to the mat (14) or to the at least one connecting leg (16), where a spud can (50) is attached to each of the at least one connecting leg, or to the lower hull (18). The offshore unit is relocatable and is a platform or a rig capable of performing drilling, production, construction, accommodation, hookup and commissioning or a combination of any of these functions thereof. The offshore unit is a self elevating mobile platform (10, 60, 62, 64) or submersible platform (70) or semi-submersible platform (58). There is also disclosed a method of installing a wellhead platform (22) for exploring hydrocarbon below seabed which includes a wellhead deck (24) and a sub-sea conductor frame (32) using an offshore unit.