Bethlehem Beaumont To Build Self-Setting Production-Storage Platform For Phillips Petroleum

The Lafayette, La., office of Phillips Petroleum Company has awarded a contract to Bethlehem Steel Corporation's Beaumont, Texas, shipyard for construction of a selfsetting production-storage platform. It will have a liquid hydrocarbon storage capacity of 11,350 barrels, and will be used offshore Texas.

The unit is the basic Bethlehem design, modified and developed by the cooperative effort of Phillips and Bethlehem to serve better the specific requirements of Phillips in the Texas offshore water.

The self-setting production-storage unit is a mat-supported jackup unit similar in configuration to the Bethlehem mat-supported jackup drilling unit. The production equipment, heliport, and quarters will be installed in the shipyard prior to the platform's being set on location in the producing fields in 54 feet of water in the Gulf of Mexico. The platform is scheduled for completion in December 1977.

The self-setting production-storage facility consists of an elevated platform supported on three tubular columns, which are in turn affixed to the supporting mat structure resting on the floor of the Gulf. The mat will provide underwater storage for liquid hydrocarbons, using Bethlehem's patented saltwater displacement system. Several compartments within the box-like platform will also provide a small portion of additional storage.

The elevated platform is a box girder-type structure, which performs several functions, i.e., provides buoyancy while the unit is in transit and while the mat is being set on location. After the unit has been set, the platform is jacked above the ocean surface to a height sufficient to provide storm wave clearance.

The fixed jacking pins are then secured in order to transfer the vertical load of the platform to the columns. Subsequently, the horizontal load transfer devices are installed between the columns and the platform. The column jacks are then removed and returned to the shipyard. Upon the eventual depletion of reserves at the first location, the entire unit will be recovered by reinstalling the jacks and reversing the latter procedure.

The Lafayette office of Phillips Petroleum played a very active role in developing the design of this unit and incorporated numerous features into this concept. Typical of these are the ability to deliver produced hydrocarbon from the underwater storage tanks without the interruption of production, the ability to divert and retreat emulsion-cut production without going to submerged storage first, and the capability of handling all fluids to prevent accidental discharge or contamination. Many safety and environmental protection precautions additional to regulatory requirements have been included.

Phillips has also secured the necessary approval from USCGS to install the platform.

Bethlehem introduced its "first" matsupported production platform in 1950, followed by the introduction of its first underwater storage facility in 1960. The combination of the technology of both companies, along with Bethlehem's many years of rigbuilding experience, has resulted in the development of this self-setting production platform.