Pressure relief actuated valves
AssigneeSchlumberger Technology Corporation
InventorsPaul G. Goughnour, Russell A. Johnston
Life of this patent
Estimating the term…
Abstract
An embodiment of a valve that is operable from one position to another position upon relief of an applied pressure includes a housing having a bore; a valve member disposed with the housing, wherein the valve member is actuated to one position in response to a certain applied pressure and actuates toward another position upon relief of the certain applied pressure; and a relief system relieving the pressure applied to the valve member when the applied pressure falls below a selected pressure level.
Claims19
A valve configured to move between a first and second position in response to applied pressure, the valve comprising:
- a housing having a bore;
- a valve member disposed with the housing, wherein the valve member is actuated to the first position in response to a certain applied pressure and is actuated to the second position upon relief of the certain applied pressure;
- and
- a pressure relief system establishing an alternative pressure relief passageway for the applied pressure when the applied pressure falls below a selected pressure level, wherein the valve member is operably coupled to the pressure relief system via a mechanical linkage.
A wellbore completion comprising:
- a tubular string disposed in the wellbore;
- a subsurface safety valve (“SSSV”) connected within the tubular string wherein the SSSV is configured to open in response to a certain applied pressure;
- a pressurized fluid source in connection with the SSSV through a control line, wherein a selected pressure level is related to a determined change in pressure from the certain applied pressure;
- a pressure relief system in fluid communication with the control line, wherein the pressure relief system provides an alternative pressure relief mechanism for pressure applied to the SSSV through the control line when the pressure falls below the selected pressure level;
- and
- a mechanical linkage operably coupling a valve member of the SSSV to the pressure relief system.
A method of ensuring positive closing of a subsurface safety valve (“SSSV”) positioned in a wellbore, the method comprising the steps of:
- supplying a hydraulic fluid through a control line to the SSSV;
- maintaining a valve member of the SSSV in an open position by a applying a certain applied hydraulic pressure through the control line;
- actuating the SSSV to close by relieving the certain applied hydraulic pressure;
- and
- releasing hydraulic fluid from the SSSV via an alternative pressure relief mechanism when the hydraulic pressure falls below a selected hydraulic pressure level, wherein the valve member is operably coupled to the pressure relief system via a mechanical linkage.
Dependencies are inferred from the claim text.