Abstract: The Removable Bottom Founded Structure (RBFS) is an offshore platform for petroleum drilling and producing operations intended for depolyment in waters with severe weather and iceberg conditions. The structure is normally held down by gravity, but during the deballasting procedure a hold-down system is employed to keep the platform on the subbase until site evacuation. 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. Flexible seals that define these chambers are positively engaged by this evacuation to create a fluid-tight seal so that no seawater will enter the evacuated chambers. The reduction of the buoyancy forces will hold the platform onto the subbase until such time as the platform is totally deballasted.

Abstract: The Removable Bottom Founded Structure (RBFS) is an offshore platform for petroleum drilling and producing operations which is deployed in waters with severe weather and iceberg conditions. The structure is normally held down by gravity, but during the deballasting procedure a hold-down system is employed to keep the platform on the subbase until site evacuation. 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. Flexible seals that define these chambers are positively engaged by water to create a fluid-tight seal so that no seawater will enter the evacuated chambers. The reduction of the buoyancy forces will hold the platform onto the subbase until such time as the platform is totally deballasted.

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. The structure is normally held down by gravity, but during the deballasting procedure a hold-down system is employed to keep the platform on the subbase until site evacuation. 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 top surface of the subbase there are circularly arranged elastomeric bearing pads that define chambers which may be evacuated by pumping and which are vented to the outside atmosphere. Pressure by the platform on the bearing pads creates a fluid-tight seal so that no seawater will enter the evacuated chambers.

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.