Halliburton Energy Services, Inc.

Otis Engineering Corporation

Nam Van Le

John C Gano

James R Longbottom

Rennie L Dickson

Robert W Crow

Ronald K Churchman

Karluf Hagen

Michael W Meaders

A tubing retrievable surface controlled subsurface safety valve 106 is adapted to be positioned in a well tubing string 102 to control the flow through the tubing string. The safety valve includes an annular housing or body 200 defining a fluid passageway through which fluids and/or gasses may flow to the surface. The safety valve is equipped with a valve closure member such as flapper 252, positioned in the fluid passageway which is moveable between an open and closed position. The valve closure member is engaged and actuated by a longitudinally extending operator 242 that engages the valve closure member 252. In one embodiment, the longitudinally extending operator 242 may be a tubular member longitudinally moveable within the valve body. The longitudinally extending member 242 is operatively coupled to a spring guide 226. A biasing spring 222 is positioned in a spring chamber 120 defined by a spring housing 228 and the spring guide 226. A spring 256 biases the closure member 252 in the closed position. A balance line 114 extending from the surface is connected to a balance pressure conduit 118 that is in fluid communication with the spring chamber 120 to balance the hydrostatic pressure from the control line 112. The spring chamber 120 is isolated from well pressure at the top and bottom therefore the pressure applied to the spring chamber 120 through the balance pressure line via the balance pressure conduit 118 counteracts the hydrostatic head of the fluid in the control line or lines, thereby enabling the subsurface safety valve 106 to operate at vary depths.

Balanced line tubing retrievable safety valve

A system for selective production from, and stimulation of, subterranean production zones while improving productivity and enhancing control of the well. Portions of a production tubing string and an internal stimulation/shifter string are assembled and run together as completion segments. Consecutive completion segments, with each segment including packers that surround sleeves and terminate at the upper end in a well control valve, are run into the cased wellbore so that the acid flow ports operated by sleeve valve assemblies are placed proximate the perforations of prospective production zones. The production zones are then stimulated as the stimulation/shifter string is moved progressively outward placing acid at each consecutive zone. The stimulation/shifter string is then removed from the production tubing string, mechanically closing the well control valve assembly by tubing manipulation. A well control valve assembly prevents flow from or to completion segments further downhole from the well control valve assembly once the stimulation/shifter string has been removed from the production tubing string. The well control valve assembly features a shaped flapper plate which, when opened, conforms closely to the shape and size of the production tubing string's interior diameter. The flapper plate is biased toward a closed position by a compression spring arrangement that includes an arm which levers the plate upward toward a seating surface. The valve assembly's closure is mechanically induced and is not responsive to a sensed well condition. Reopening of the valve assembly is accomplished by insertion into the assembly of a tubular member, or 'stinger', which is incorporated into a running arrangement. The stinger is described in relation to a seal assembly which is capable of reopening the well control valve and securing it in the open position. The seal assembly is incorporated into a running arrangement and inserted into the valve assembly to open the valve assembly and seal the connection between the seal assembly and the well control valve assembly.

Well completion system with well control valve

A lift gas safety valve has a compound valve closure assembly which will close automatically upon loss of hydraulic control pressure, and which can be reopened and maintained in the open position by the application of hydraulic control pressure at a relatively low pressure level. A primary valve closure member is slideably mounted onto a valve stem for movement to a seated position on the valve body in which a lift gas flow passage is closed, to an unseated position in which the lift gas flow passage is opened. A bypass flow passage is formed between the stem and the primary valve closure member for establishing fluid flow communication between the lift gas flow passage and the outlet port when the primary valve closure member is in its seated position. The auxiliary valve closure member is mounted onto the valve stem for movement from a seated position on the primary valve closure member to an unseated position for selectively closing and opening the bypass flow passage. According to this arrangement, when the auxiliary valve closure member is moved to its open position, the pressure differential across the safety valve is equalized, thereby permitting the main valve closure member to be unseated by the application of hydraulic control fluid at a relatively low pressure level.

Annular safety system for gas lift production

Growing community of inventors

Lewisville, TX, United States of America

Nam Van Le