The Use of Buoyancy to Lift Heavy Objects from the Sea.

摘要

To recover oil from economically marginal offshore fields the re-use of production platforms has been considered. Re-use involves severing the jacket from the seabed, rotating the jacket to the horizontal and lifting it through the air/sea interface in a configuration suitable for towing. Five systems are considered for use in the recovery process. Two systems currently used for installation are found suitable for modification to recover jackets. They are the pontoon barge system and the self-floating tower. Major problems to be overcome in modifying for retraction are mating of the pontoon barge with the tower, developing a pile system which can be refurbished, and ensuring transverse stability on retraction through the air/sea interface.