Subsea station

Abstract

A subsea station or installation in which one or more rigid elongated base template frames are adapted to be permanently positioned on a sea floor. Each base template frame includes a plurality of framed receptor openings, each adapted to receive a module guide base for aligning and releasably connecting thereto module unitary assemblies, each of which carries selected equipment in a protected manner. Extending along each side of the base frame are elongated side structures releasably connected to the base frame and recoverable for maintenance and service, each side structure extending outboardly of the sides of the base frame and being adapted to carry fluid conducting lines, power lines, and a rail means for guidance of a submarine capsule along the length of the base frame. Flowlines for conducting fluid to a remote platform or onshore installation are connected to the fluid conducting lines on the side structures by means of a transversely disposed pipe loop means supported from the base frame and arranged to compensate for expansion and contraction of the flowlines and pipelines and to provide yieldability in the makeup connections of flowlines to the pipe loop means. The rigid base frame includes guide and support members for power control means such as electrical and hydraulic actuating means for operation of the equipment carried by the modular assemblies and by the rigid base frame. A method is disclosed of lowering a rigid base template frame from a work boat while assisted by a drill ship and of controlling selected orientation of the base frame to and in a selected position on the sea floor.