Isolation Barrier

Abstract

An apparatus and method for securing a tubular within another tubular or borehole, creating a seal across an annulus in a well bore, and centralising or anchoring tubing within a wellbore. A sleeve is arranged on a tubular body to create a chamber therebetween. A port provides fluid access through the body to the chamber. A torsion spring is located within the chamber. When fluid is introduced into the chamber the sleeve is morphed to secure it to a well bore wall and the torsion spring unwinds to a relaxed state. The relaxed torsion spring supports the morphed sleeve against collapse.

1 . An assembly, comprising:
 a tubular body arranged to be run in and secured within a larger diameter generally cylindrical structure;   a sleeve member positioned on the exterior of the tubular body, to create a chamber therebetween;   the tubular body including a port to permit the flow of fluid into the chamber to cause the sleeve member to move outwardly and morph against an inner surface of the larger diameter structure; and   characterised in that:   at least one torsion spring is located within the chamber;   the torsion spring relaxing as the sleeve member is moved outwardly by fluid pressure to provide a frame within the chamber when the sleeve member is morphed against the inner surface of the larger diameter structure.   
     
     
         2 . An assembly according to  claim 1  wherein, the torsion spring is a helically coiled spring which unwinds as it relaxes. 
     
     
         3 . An assembly according to  claim 1 , the torsion spring has a relaxed diameter less than a diameter of the larger diameter structure. 
     
     
         4 . An assembly according to  claim 3  wherein, the torsion spring has a relaxed diameter less than a diameter of the morphed sleeve. 
     
     
         5 . An assembly according to  claim 1  wherein, the torsion spring has a rectangular cross-section. 
     
     
         6 . An assembly according to  claim 1  wherein, the torsion spring has a square cross-section. 
     
     
         7 . An assembly according to  claim 1  wherein, the sleeve member has a first end which is affixed and sealed to the tubular body and a second end which includes a sliding seal to permit longitudinal movement of the second end over the tubular body. 
     
     
         8 . An assembly according to  claim 1  wherein the large diameter structure is selected from a group comprising: an open hole borehole, a borehole lined with a casing or liner string, a borehole lined with a casing or liner string which is cemented in place downhole; a pipeline within which another smaller diameter tubular section requires to be secured or a pipeline within which another smaller diameter tubular section requires to be centralised. 
     
     
         9 . An assembly according to  claim 1  wherein the tubular body is located coaxially within the sleeve and is part of a tubular string used within a wellbore. 
     
     
         10 . An assembly according to  claim 1  wherein there is a plurality of ports arranged through the tubular body. 
     
     
         11 . An assembly according to  claim 1  wherein the port includes a barrier. 
     
     
         12 . An assembly according to  claim 11  wherein the barrier is a rupture disc which allows fluid to flow through the port at a predetermined fluid pressure. 
     
     
         13 . An assembly according to  claim 11  wherein the barrier includes a valve. 
     
     
         14 . An assembly according to  claim 13  wherein the valve is a one-way check valve. 
     
     
         15 . A method of setting a morphed sleeve in a well bore, comprising the steps:
 (a) locating a sleeve member on the exterior of a tubular body and sealing it thereto to create a chamber therebetween,   (b) locating a torsion spring in the chamber;   (c) running the tubular body on a tubular member into a wellbore and positioning the sleeve member at a desired location within a larger diameter structure;   (d) pumping fluid through the tubular member and through a port in the tubular body to access the chamber;   (e) causing the sleeve member to move radially outwardly and morph against an inner surface of the larger diameter structure;   (f) allowing the torsion spring to relax and exert a radial force on the sleeve member as the sleeve member is moved radially outwardly towards the inner surface of the larger diameter structure; and   (g) creating a frame from the relaxed torsion spring to prevent collapse of the morphed sleeve member.   
     
     
         16 . A method of setting a morphed sleeve in a well bore according to  claim 15  wherein, the method includes the step of selecting a torsion spring having a relaxed diameter less than a diameter of the larger diameter structure. 
     
     
         17 . A method of setting a morphed sleeve in a well bore according to  claim 16  wherein, the method includes the step of selecting a torsion spring having a relaxed diameter less than a calculated diameter of the morphed sleeve. 
     
     
         18 . A method of setting a morphed sleeve in a well bore according to any  claim 15  wherein step (d) includes the step of pumping fluid through the tubular member and through multiple ports in the tubular body to access the chamber. 
     
     
         19 . A method of setting a morphed sleeve in a well bore according to  claim 15  wherein the method includes the step of rupturing a disc at a valve in the port to allow fluid to enter the chamber when the pressure reaches a desired value. 
     
     
         20 . A method of setting a morphed sleeve in a well bore according to  claim 15  wherein the method includes the steps of running in an activation fluid delivery tool, creating a temporary seal above and below the port and injecting fluid from the tool into the chamber via the port.