Warren S Fine

US Patent:

47550821, Jul 5, 1988

Filed:

May 1, 1987

Appl. No.:

7/045028

Inventors:

Robert H. Beskow - Midland TX
Patrick J. Dunn - Pleasant Hill CA
Warren S. Fine - Kenwood CA

Assignee:

Chevron Research Company - San Francisco CA

International Classification:

E02B 1702

US Classification:

405217

Abstract:

The Removable Bottom Founded Structure (RBFS) is an offshore platform for petroleum drilling and producing operations intended for deployment in waters with severe weather and iceberg conditions. It is a two-part structure comprising (1) a platform which is made up of a deck structure, multiple columns and braces; and (2) a reinforced concrete subbase that rests on the sea floor and upon which the platform is founded. The structure is normally held down by gravity for standard platform operations, but during the deballasting procedure due to an iceberg emergency a hold-down system is employed to keep the platform on the subbase until full deballasting is achieved. The system that is used to hold the platform down onto the subbase is located where the platform meets the subbase. It operates on the principle of hydrostatics. On the underside of the columns there are multiple chambers which may be evacuated by pumping and which are vented to the outside atmosphere.