Removable subsea test valve system for deep water

摘要

A subsea test valve system for wells completed at the floor of the sea includes a safety valve and disconnect mechanism mounted in a blowout preventer at the bottom of the sea and having hydraulic fluid pressure operated means for opening the safety valve and controlling a latch in the disconnect mechanism. A tubing test string shut off valve is releasably latched in the disconnect mechanism and has a hydraulic fluid operated shut off valve and a valve for venting the test string to the riser pipe which extends from the blowout preventer to the vessel or platform at the surface of the sea. The subsea hydraulic pressure operated devices are supplied with pressure fluid from a subsea accumulator under the control of subsea pilot valves which are operated by small pressure differences, to accomplish rapid operation at great depth from a control console on the vessel or platform.