Tubing hanger running tool and subsea test tree control system

Abstract

A system for providing power to elements down-hole in a subsea well includes a control pod having at least one shuttle valve, a down-hole hydraulically-actuated device having at least one internal porting mechanism in fluid communication with the at least one shuttle valve, a blowout preventer stack connected to the down-hole device, the blowout preventer stack including a first ram and a second ram, and a choke line in fluid communication with an area between the first ram and the second ram. The at least one shuttle valve controls distribution of hydraulic pressure applied through the choke line to the internal porting mechanism for selective distribution of power to the hydraulically-actuated device.

Description

RELATED APPLICATIONS [0001] This application claims priority to U.S. Provisional Application No. 60 / 558,078, entitled, “Subsea Test Tree,” filed Mar. 30, 2004, and to U.S. Provisional Application No. 60 / 580,474, entitled, “Tools for Completing Subsea Wells,” filed Jun. 17, 2004, each of which is herein incorporated by reference.FIELD OF THE INVENTION [0002] This invention relates to subsea well technology, and specifically to an improved tubing hanger running tool and subsea test tree control system and method of controlling hydraulic / electric tools or equipment used during drilling, testing or completion of a subsea well. BACKGROUND OF THE INVENTION [0003] A subsea well constructed for producing hydrocarbons consists of a series of concentric drilled and cased bores. The casings typically include sections of threaded and coupled pipes screwed together. The casings are run into the well bore, suspended (landed) in a wellhead attached to the first casing string (referred to as conduc...

AI Technical Summary

Benefits of technology

[0011] Various features of the invention may provide one or more of the following capabilities. Using the sealing capabilities of the BOP and the existing hydraulic power and control functions allows the user to avoid having to obtain the umbilical, the control unit and a hydraulic power supply. Also, rig time is lessened due to the elimination of the necessity of hooking up the aforementioned components, as well as the time required to run the umbilical. Savings can be as much as one-half of the standard cost of renting and running a known subsea test tree. Safety is enhanced by the elimination of the control umbilical required in the current SSTT designs.

[0012] Various features of the invention may provide one or more of the following capabilities. In embodiments of the invention, the need for a hose reel, a control umbilical, a hydraulic control panel, a hydraulic power supply and down-hole accumulator are substantially eliminated. The rig time associated with running the control umbilical is also substantially eliminated. The efficiency of the drilling of a subsea well can be more cost effective and safer for the user.

Problems solved by technology

The process of running the SSTT is cumbersome and time consuming to the well operator and requires the rental of expensive equipment (i.e. control panel, hydraulic power supply, control umbilical, hose reel, etc.).

The cost can include the rental cost of the SSTT itself, the umbilical, and the control panel and hydraulic power system, as well as the rig time to run the SSTT with the umbilical, strapping the umbilical to the tie back string and rigging up the hydraulic control system.

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