Automatically Resetting Tubing String Bypass Valve

Abstract

A bypass valve has a tubular housing for connection in series with a wellbore tubing string supporting a sliding sleeve biased from an open position towards a closed position relative to a bypass port in the housing. A first sealing interface between the sleeve and housing at one side of the port to maintain a fluid seal throughout sliding movement, while a second sealing interface between the sleeve and the housing at an opposing second side of the port maintains a fluid seal only in the closed position. A spring applies a prescribed closing force to the sliding sleeve to retain the sliding sleeve in the closed position only when pressure within the tubular housing which acts on the sliding sleeve through the bypass port is below the prescribed closing force of the spring.

1 . A bypass valve for use with a tubing string within a wellbore, the bypass valve comprising:
 a tubular housing having a longitudinal passage communicating therethrough between longitudinally opposing ends of the tubular housing and a bypass port communicating from the longitudinal passage to an exterior of the tubular housing, the ends of the tubular housing being adapted to be connected in series with the tubing string;   a sliding sleeve supported on the tubular housing so as to be longitudinally slidable along the tubular housing in a first direction from a closed position preventing escape of fluid through the bypass port from the longitudinal passage of the tubular housing to an exterior of the bypass valve and an open position in which the bypass port is in open communication between the longitudinal passage and the exterior of the bypass valve;   a spring operatively connected to the sliding sleeve so as to bias the sliding sleeve relative to the tubular housing in a second direction towards the closed position;   a first sealing interface at a location which is offset from the bypass port in the first direction and which is arranged to maintain a fluid seal between the sliding sleeve and the tubular housing throughout movement of the sliding sleeve between the open and closed positions thereof;   a second sealing interface at a location which is offset from the bypass port in the second direction and which is arranged to maintain a fluid seal between the sliding sleeve and the tubular housing only in the closed position of the sliding sleeve;   the spring being adapted to apply a prescribed closing force to the sliding sleeve such that the spring is adapted to (i) retain the sliding sleeve in the closed position when pressure within the tubular housing which acts on the sliding sleeve through the bypass port is below the prescribed closing force of the spring, (ii) allow the sliding sleeve to be displaced from the closed position towards the open position when the pressure within the tubular housing which acts on the sliding sleeve through the bypass port exceeds the prescribed closing force of the spring, and (iii) displace the sliding sleeve into the closed position from the open position when the pressure within the tubular housing which acts on the sliding sleeve through the bypass port falls below the prescribed closing force of the spring.   
     
     
         2 . The bypass valve according to  claim 1  wherein the second sealing interlace comprises sealing faces on the tubular housing and on the sliding sleeve which are oriented transversely to a longitudinal direction of tubular housing. 
     
     
         3 . The bypass valve according to  claim 2  wherein the sealing face on the sliding sleeve of the second sealing interface is located at an end of the sliding sleeve in the longitudinal direction of the sliding sleeve. 
     
     
         4 . The bypass valve according to  claim 2  wherein the sealing faces of the second sealing interlace become separated from one another immediately upon displacement of the sliding sleeve from the closed position. 
     
     
         5 . The bypass valve according to  claim 1  wherein the second sealing interface comprises metallic sealing faces on each of the tubular housing and the sliding sleeve. 
     
     
         6 . The bypass valve according to  claim 1  in combination with the tubing string within the wellbore and a tubing drain connected in series with the tubing string in which the tubing drain is adapted to open when pressure within the tubing string exceeds a prescribed upper limit, the prescribed closing force of the spring being adapted to be overcome by a prescribed intermediate pressure limit which is less than the prescribed upper limit of the tubing drain. 
     
     
         7 . The bypass valve according to  claim 1  in combination with the tubing string within the wellbore, the bypass valve being connected in series with the tubing string in proximity to a top end of the tubing string. 
     
     
         8 . The bypass valve according to  claim 1  further comprising a gate member supported on the tubular housing so as to be longitudinally slidable along the tubular housing independently of the sliding sleeve between an open position in which the bypass port is unobstructed by the gate member and a closed position in which the bypass port is closed by the gate member. 
     
     
         9 . The bypass valve according to  claim 8  wherein the sliding sleeve is supported externally of the tubular housing, and the gate member is supported internally within the tubular housing. 
     
     
         10 . The bypass valve according to  claim 8  for use with an insert pump having a working barrel defining an outer diameter, wherein the gate member is a tubular sleeve having a main portion with a first internal diameter and a seat portion with a second internal diameter which is reduced relative to the first internal diameter and which is arranged to receiving the outer diameter of the working barrel of the insert pump seated therein. 
     
     
         11 . The bypass valve according to  claim 10  in combination with the insert pump, wherein the second internal diameter of the seat portion of the gate member frictionally receives the outer diameter of the working barrel of the insert pump by interference fit therein such that the gate member is movable between the open and closed positions thereof together with longitudinal displacement of the working barrel of the insert pump relative to the tubing string. 
     
     
         12 . The bypass valve according to  claim 8  wherein the tubular housing includes a retainer recess formed in an inner wall of the tubular housing and the gate member includes a locking portion which is biased from an unlocked position in which the locking portion does not interfere with displacement of the gate member between the open and closed positions towards a locked position in which the locking portion protrudes from an outer diameter of the gate member so as to be received in the retainer recess in the open position of the gate member for retaining the gate member in the open position. 
     
     
         13 . The bypass valve according to  claim 12  wherein the retainer recess comprising an annular groove in the inner wall of the tubular housing and wherein the locking portion comprises a plurality of fingers extending axially from one end of the tubular housing to respective free ends of the fingers supporting respective protrusions thereon which are received within the annular groove in the open position of the gate member. 
     
     
         14 . A bypass valve for use with a tubing string within a wellbore having a tubing drain connected in series with the tubing string in which the tubing drain is adapted to open when pressure within the tubing string exceeds a prescribed upper limit, the bypass valve comprising:
 a tubular housing having a longitudinal passage communicating therethrough between longitudinally opposing ends of the tubular housing and a bypass port communicating from the longitudinal passage to an exterior of the tubular housing, the ends of the tubular housing being adapted to be connected in series with the tubing string;   a sliding sleeve supported on the tubular housing so as to be longitudinally slidable along the tubular housing in a first direction from a closed position preventing escape of fluid through the bypass port from the longitudinal passage of the tubular housing to an exterior of the bypass valve and an open position in which the bypass port is in open communication between the longitudinal passage and the exterior of the bypass valve;   a spring operatively connected to the sliding sleeve so as to bias the sliding sleeve relative to the tubular housing in a second direction towards the closed position;   the spring being adapted to apply a prescribed closing force to the sliding sleeve such that the spring is adapted to (i) retain the sliding sleeve in the closed position when pressure within the tubular housing which acts on the sliding sleeve through the bypass port is below the prescribed closing force of the spring, (ii) allow the sliding sleeve to be displaced from the closed position towards the open position when the pressure within the tubular housing which acts on the sliding sleeve through the bypass port exceeds the prescribed closing force of the spring, and (iii) displace the sliding sleeve into the closed position when the pressure within the tubular housing which acts on the sliding sleeve through the bypass port falls below the prescribed closing force of the spring;   the prescribed closing force of the spring being adapted to be overcome by a prescribed intermediate pressure limit which is less than the prescribed upper limit of the tubing drain.   
     
     
         15 . A bypass valve in combination with a tubing string within a wellbore, the bypass valve comprising:
 a tubular housing having a longitudinal passage communicating therethrough between longitudinally opposing ends of the tubular housing and a bypass port communicating from the longitudinal passage to an exterior of the tubular housing, the ends of the tubular housing being connected in series with the tubing string;   a sliding sleeve supported on the tubular housing so as to be longitudinally slidable along the tubular housing in a first direction from a closed position preventing escape of fluid through the bypass port from the longitudinal passage of the tubular housing to an exterior of the bypass valve and an open position in which the bypass port is in open communication between the longitudinal passage and the exterior of the bypass valve;   a spring operatively connected to the sliding sleeve so as to bias the sliding sleeve relative to the tubular housing in a second direction towards the closed position;   the spring being adapted to apply a prescribed closing force to the sliding sleeve such that the spring is adapted to (i) retain the sliding sleeve in the closed position when pressure within the tubular housing which acts on the sliding sleeve through the bypass port is below the prescribed closing force of the spring, (ii) allow the sliding sleeve to be displaced from the closed position towards the open position when the pressure within the tubular housing which acts on the sliding sleeve through the bypass port exceeds the prescribed closing force of the spring, and (iii) displace the sliding sleeve into the closed position when the pressure within the tubular housing which acts on the sliding sleeve through the bypass port falls below the prescribed closing force of the spring;   the bypass valve being connected in series with the tubing string in proximity to a top end of the tubing string.