A pressure testable toe sleeve and a method for pressure testing a wellbore

Abstract

A method for pressure testing a wellbore casing and establishing fluid communication between a first location inside a wellbore and a second location and/or a third location. The method comprises providing a pressure testable toe sleeve for use in a wellbore. The pressure testable toe sleeve comprises a port allowing fluid communication of a displacement fluid between the first location inside the wellbore and a chamber, via a first valve configured to open at or below the required test pressure, and the port being pluggable by a plug; the plug being configured to prevent ingress of cement into the port during a cementing operation, and the first valve being configured to allow fluid communication between the first location and the chamber when the first valve is open. The method further comprises conducting a cementing operation while the plug is plugging the port, the cementing operation comprising using a cementing dart to separate the cement from a displacement fluid; testing the casing at the required test pressure, opening the first valve, and removing the plug, allowing the displacement fluid to flow from the first location in the wellbore to the chamber, and the displacement fluid to flow to the second location and/or the third location. A pressure testable toe sleeve for use in a wellbore. The pressure testable toe sleeve comprises a port allowing fluid communication of a displacement fluid between the first location inside the wellbore and a chamber, via a first valve configured to open at or below the required test pressure, and the port being pluggable by a plug. The plug is configured to prevent ingress of cement into the port during a cementing operation, and the first valve is configured to allow fluid communication between the first location and the chamber when the first valve is open.

1 . A method for pressure testing a wellbore casing and establishing fluid communication between a first location inside a wellbore and a second location and/or a third location, the method comprising:
 providing a pressure testable toe sleeve for use in a wellbore, the pressure testable toe sleeve comprising:   a port allowing fluid communication of a displacement fluid between the first location inside the wellbore and a chamber, via a first valve configured to open at or below the required test pressure, and the port being pluggable by a plug;   the plug being configured to prevent ingress of cement into the port during a cementing operation,   and the first valve being configured to allow fluid communication between the first location and the chamber when the first valve is open;   the method further comprising:
 conducting a cementing operation while the plug is plugging the port, the cementing operation comprising using a cementing dart to separate the cement from a displacement fluid; 
 testing the casing at the required test pressure, opening the first valve, and removing the plug, allowing the displacement fluid to flow from the first location in the wellbore to the chamber, and the displacement fluid to flow to the second location and/or the third location. 
   
     
     
         2 . A method according to  claim 1 , wherein the plug is degradable when in contact with the displacement fluid, and wherein the step of removing the plug comprises waiting for the plug to degrade, the degradation of the plug occurring after the cementing operation, but before the pressure testing of the wellbore casing. 
     
     
         3 . A method according to  claim 1 , wherein there are a plurality of plugs. 
     
     
         4 . A method according to  claim 2 , wherein the material and/or the shape, and/or the dimensions of the degradable plug are chosen to provide a desired degradation time. 
     
     
         5 . A method according to  claim 4 , wherein the degradation time of the degradable plug is between 10 hours and 100 hours. 
     
     
         6 . A method according to  claim 1 , wherein the first valve is a first piston held in position by one or more shear pins, and the step of opening the first valve comprises the pressure of the testing shearing the shear pins, allowing the first piston to be moved by the displacement fluid. 
     
     
         7 . A method according to  claim 1 , wherein the chamber comprises a second valve, the second valve preventing fluid connection between the chamber and the second location when the second valve is closed, and allowing fluid connection between the chamber and the second location when the second valve is open. 
     
     
         8 . A method according to  claim 7 , wherein the second valve is controlled by a degradable stop, the degradable stop being degradable when in contact with the displacement fluid, and the step of opening the second valve comprises waiting for the degradable stop to degrade. 
     
     
         9 . A method according to  claim 8 , wherein the second valve comprises a second piston held in position by the degradable stop, and the step of opening the second valve further comprises the second piston being moved by the displacement fluid after the degradable stop has degraded. 
     
     
         10 . A method according to  claim 9 , wherein the material and/or the shape, and/or the dimensions of the degradable stop are chosen to provide a desired degradation time. 
     
     
         11 . A method according to  claim 10 , wherein the degradation time of the degradable stop is between 30 minutes and 48 hours. 
     
     
         12 . A method according to  claim 1 , wherein the second location is outside the wellbore. 
     
     
         13 . A method according to  claim 1 , wherein the cementing operation further comprises the cementing dart impacting a blockade, the blockade allowing cement to pass through the blockade, but not allowing the cement dart to pass the blockade, and the blockade being held in position by a removable blockade holder. 
     
     
         14 . A method according to  claim 13 , wherein the blockade holder comprises a degradable blockade holder that is removed by degrading in contact with the displacement fluid. 
     
     
         15 . A method according to  claim 14 , wherein displacement fluid in the chamber is in contact with the degradable blockade holder, thereby removing it. 
     
     
         16 . (canceled) 
     
     
         17 . A method according to  claim 13 , wherein the method further comprises:
 waiting for the removable blockade holder to be removed;   the removal of the removable blockade holder allowing the displacement fluid to force the cementing dart to a second position downhole of the initial position of the cementing dart.   
     
     
         18 . A method according to  claim 17 , wherein the third location is inside the wellbore, downhole of the second position of the cementing dart, wherein the method further comprises:
 the movement of the cementing dart to a second position allowing the displacement fluid to flow from the first location to the third location.   
     
     
         19 . A method according to  claim 1 , wherein the test pressure is higher than the pressure in the wellbore after testing. 
     
     
         20 . A pressure testable toe sleeve for use in a wellbore, the pressure testable toe sleeve comprising:
 a port allowing fluid communication of a displacement fluid between the first location inside the wellbore and a chamber, via a first valve configured to open at or below the required test pressure, and the port being pluggable by a plug;   the plug being configured to prevent ingress of cement into the port during a cementing operation,   and the first valve being configured to allow fluid communication between the first location and the chamber when the first valve is open.