Wellbore Shut Off Valve with Hydraulic Actuator System

Abstract

A wellbore shut-off valve is operably associated with a valve actuator so that the shut-off valve can be selectively moved between open and closed conditions when desired rather than opening and closing occurring automatically as portions of the production assembly are removed or replaced in the wellbore.

1 . A shut-off valve assembly for use in selectively closing off a section of wellbore to fluid flow, the assembly comprising:
 a shut-off valve incorporated within a completion string within the wellbore, the shut-off valve being moveable between an open condition wherein fluid may flow through the completion string, and a closed condition, wherein fluid flow through the completion string is blocked; and   a valve actuator incorporated within the completion string and associated with the shut-off valve, the valve actuator operating the shut-off valve between its open and closed conditions.   
     
     
         2 . The shut-off valve assembly of  claim 1  wherein the shut-off valve comprises a ball valve. 
     
     
         3 . The shut-off valve assembly of  claim 1  wherein the valve actuator is hydraulically actuated. 
     
     
         4 . The shut-off valve assembly of  claim 1  wherein the valve actuator further comprises:
 a housing;   a sleeve moveably disposed within the housing; and   a shifting portion affixed to the sleeve, the shifting portion being operable to move the shut-off valve between open and closed conditions upon movement of the sleeve with respect to the housing.   
     
     
         5 . The shut-off valve assembly of  claim 1  further comprising a programmable controller operably associated with the valve actuator to cause the valve actuator to operate the shut-off valve between open and closed conditions in accordance with a predetermined scheme. 
     
     
         6 . The shut-off valve assembly of  claim 5  wherein the controller is operably associated with the valve actuator by control of a fluid pump supplying hydraulic control fluid to the valve actuator. 
     
     
         7 . A shut-off valve assembly for use in selectively closing off a section of wellbore to fluid flow, the assembly comprising:
 a shut-off ball valve incorporated within a completion string within the wellbore, the shut-off ball valve being moveable between an open condition wherein fluid may flow through the completion string, and a closed condition, wherein fluid flow through the completion string is blocked; and   a valve actuator incorporated within the completion string and associated with the shut-off valve, the valve actuator operating the shut-off valve between its open and closed conditions.   
     
     
         8 . The shut-off valve assembly of  claim 7  wherein the valve actuator further comprises:
 a housing;   a sleeve moveably disposed within the housing; and   a shifting portion affixed to the sleeve, the shifting portion being operable to move the shut-off valve between open and closed conditions upon movement of the sleeve with respect to the housing.   
     
     
         9 . The shut-off valve assembly of  claim 7  wherein the valve actuator is hydraulically actuated. 
     
     
         10 . The shut-off valve assembly of  claim 7  further comprising a programmable controller operably associated with the valve actuator to cause the valve actuator to operate the shut-off valve between open and closed conditions in accordance with a predetermined scheme. 
     
     
         11 . The shut-off valve assembly of  claim 10  wherein the controller is operably associated with the valve actuator by control of a fluid pump supplying hydraulic control fluid to the valve actuator. 
     
     
         12 . A method of selectively shutting off a wellbore so that an upper portion of a completion assembly within the wellbore may be removed, the method comprising the steps of:
 operably associating a wellbore shut-off valve which is operable between open and closed conditions with a valve actuator that controls movement of the valve between open and closed conditions;   operating the valve actuator to move the shut-off valve to the closed condition; and   detaching and removing the upper completion assembly portion from a lower completion portion within the wellbore after the shut-off valve has been closed.   
     
     
         13 . The method of  claim 12  further comprising the steps of:
 reattaching the upper completion portion to the lower completion portion; and   after reattaching the upper completion portion to the lower completion portion, operating the valve actuator to move the shut-off valve to the open condition.   
     
     
         14 . The method of  claim 12  wherein the step of operating the valve actuator to move the shut-off valve to the closed condition is conducted by a programmable controller. 
     
     
         15 . The method of  claim 13  wherein the step of operating the valve actuator to move the shut-off valve to the open condition is conducted by a programmable controller.