Downhole sealing devices having a shape-memory material and methods of manufacturing and using same

Abstract

Sealing devices such as packers comprise a shape-memory material having a compressed run-in position or shape and an original expanded position or shape. The shape-memory material may comprise a polyurethane foam material held in the compressed run-in position by an adhesion material that is dissolvable by a fluid. The fluid may be a wellbore fluid already present in the wellbore or a fluid pumped down the wellbore after the sealing device is disposed within the wellbore. The fluid may also be a production fluid from the well. Upon being contacted by the fluid, the adhesion material dissolves and the shape-memory material expands to its original expanded position or shape, thereby sealing and dividing the annulus of the wellbore.

1 . A sealing device for use in a wellbore to isolate an annulus of the wellbore, the sealing device comprising:
 a shape-memory material, the shape-memory material having a compressed position and an expanded position and the shape-memory material being maintained in the compressed position by a dissolvable adhesion material,   wherein the dissolvable adhesion material is dissolvable by a wellbore fluid placed in contact with the adhesion material.   
     
     
         2 . The sealing device of  claim 1 , wherein the shape-memory material comprises a polyurethane foam material. 
     
     
         3 . The sealing device of  claim 1 , wherein the dissolvable adhesion material comprises a polymer. 
     
     
         4 - 19 . (canceled) 
     
     
         20 . A method of sealing wellbore to divide an annulus of the wellbore, the method comprising:
 (a) securing a downhole tool to a string of tubing, the downhole tool comprising a sealing device comprising a shape-memory material, the shape-memory material having a compressed run-in position and an original expanded position, wherein the shape-memory material is maintained in the compressed run-in position by a dissolvable adhesion material;   (b) running the downhole tool in a wellbore;   (c) contacting the shape-memory material and dissolvable adhesion material with a fluid;   (d) dissolving the dissolvable adhesion material with the fluid;   (e) expanding the shape-memory material from the compressed run-in position to the original expanded position, thereby sealing and dividing the annulus of wellbore with the shape-memory material in the original expanded position.   
     
     
         21 . The method of  claim 20 , wherein the fluid is water. 
     
     
         22 . The method of  claim 20 , wherein the fluid is oil.