ONE-ATMOSPHERE PRODUCTION SYSTEMS FOR USE IN DEEP WATER

Abstract

The establishment of a joint industry sponsored subsea production system development program in early 1973 has resulted in the development of field-proven systems for the subsea production of oil and gas using the one atmosphere chamber concept.

The program was completed in mid 1978 with the development of a deep-water multi-well drilling and producing station for the subsea production of oil and gas. Deep water is used here to refer to 3000 ft (915 m) and beyond. This study has resulted in equipment designs to provide for:

A multi-well drilling and producing template to allow drilling and completion of approximately ten wells from a single rig location.

Commingling of production from the wells into a common manifold chamber without laying flow lines.

Connection of the production, service and electrical lines through a production riser, remotely located from the template wells, to a floating facility.

Installation and servicing of subsea equipment using a one-atmosphere service system for deep water.

The development of the deepwater system was preceded by the design, installation and operation of shallow-water equivalents.

In October 1972, a one-atmosphere wellhead chamber was installed on a subsea well in 37S ft (114 m) of water in the Main Pass 290 field, offshore Louisiana. Subsequently, a one- atmosphere subsea manifold center designed to serve two subsea wells, completed with one-atmosphere wellhead chambers and one platform well, was installed. Since the August 1976 start-up of this subsea manifold center system, more than 300,000 barrels of oil and 680,000 MSCF of gas have been produced.