Anti-extrusion assembly for a packing element system

Abstract

The present invention generally relates to an apparatus and a method for sealing a wellbore. In one aspect, a sealing apparatus for use in a wellbore is provided. The apparatus includes a compressible sealing member disposed around a body and an anchoring device. The apparatus further includes an anti-extrusion assembly having at least one flexible segment and one seal ring disposable a each end of the compressible sealing member, wherein the anti-extrusion assembly is constructed and arranged to form a barrier around the ends of the compressible sealing member upon expansion thereof. In another aspect, a downhole tool for sealing an annulus of a wellbore is provided. In yet another aspect, a method for sealing a wellbore is provided.

1 . A sealing apparatus for use in a wellbore, comprising: 
 a body;    a compressible sealing member disposed around the body;    an anti-extrusion assembly having at least one flexible segment and one seal ring disposable at each end of the compressible sealing member, wherein the anti-extrusion assembly is constructed and arranged to form a barrier around the ends of the compressible sealing member upon expansion thereof; and    an anchoring device.    
     
     
         2 . The apparatus of  claim 1 , wherein the flexible segment is fabricated from a highly elastic material capable of forming to a contour of a defined area.  
     
     
         3 . The apparatus of  claim 1 , wherein the seal ring secures the compressible sealing member to the body.  
     
     
         4 . The apparatus of  claim 1 , wherein the flexible segment is fabricated as part of the seal ring.  
     
     
         5 . The apparatus of  claim 1 , further including a plurality of split rings disposed adjacent the anti-extrusion assembly.  
     
     
         6 . The apparatus of  claim 5 , wherein the anchoring device consists of a plurality of cones and slips.  
     
     
         7 . The apparatus of  claim 6 , wherein the anti-extrusion assembly is formed into the profile of the plurality of cones and the plurality of split rings upon expansion of the compressible sealing member.  
     
     
         8 . The apparatus of  claim 1 , wherein the anti-extrusion assembly forms the barrier around a lower portion of the compressible sealing member to prevent the compressible sealing member from extruding under the anchoring device.  
     
     
         9 . The apparatus of  claim 1 , wherein the mating surface of the anti-extrusion assembly includies a smooth machined surface and a slick coating.  
     
     
         10 . The apparatus of  claim 1 , further including a spacer disposed at the lower end of the flexible segment.  
     
     
         11 . The apparatus of  claim 1 , wherein the flexible segment is disposed adjacent the seal ring.  
     
     
         12 . A downhole tool for sealing an annulus of a wellbore, comprising: 
 a body; and    an anchoring and sealing system disposed about the body, wherein the anchoring and sealing system comprises: 
 a compressible sealing member;  
 an anti-extrusion assembly having at least one flexible segment and one seal ring disposable a each end of the compressible sealing member, wherein the anti-extrusion assembly is constructed and arranged to form a barrier around the ends of the compressible sealing member upon expansion thereof;  
 a cone and slip arrangement; and  
 a plurality of split rings disposed adjacent the anti-extrusion assembly.  
   
     
     
         13 . The downhole tool of  claim 12 , wherein the flexible segment is fabricated from a highly elastic material capable of forming to a contour of a defined area.  
     
     
         14 . The downhole tool of  claim 12 , wherein the flexible segment forms the barrier around the lower portion of the compressible sealing member.  
     
     
         15 . The downhole tool of  claim 12 , wherein the flexible segment is fabricated as part of the seal ring.  
     
     
         16 . A method for sealing a wellbore, comprising: 
 running a sealing apparatus in to the wellbore, the sealing apparatus comprising: 
 a body;  
 a compressible sealing member disposed around the body;  
 an anti-extrusion assembly having at least one flexible segment and one seal ring disposable a each end of the compressible sealing member, wherein the anti-extrusion assembly is constructed and arranged to form a barrier around the ends of the compressible sealing member upon expansion thereof; and  
 an anchoring device;  
   applying an axial force to the sealing apparatus to cause the anchoring device to grip the wellbore;    expanding the sealing member into contact with an area of the wellbore; and    deforming the flexible segment and creating a barrier to prevent the sealing member from extruding under the anchoring device.    
     
     
         17 . The method of  claim 16 , wherein the flexible segment is fabricated from a highly elastic material capable of forming to a contour of a defined area.  
     
     
         18 . The method of  claim 16 , wherein the anchoring device consists of a cone and slip arrangement.  
     
     
         19 . The method of  claim 16 , further including bridging any gaps between the sealing member and the anchoring device due to activation of the sealing apparatus.  
     
     
         20 . The method of  claim 16 , wherein the sealing apparatus further includes a plurality of split rings disposed adjacent the anti-extrusion assembly.  
     
     
         21 . The method of  claim 20 , further including containing the sealing member within a predefined space by the anti-extrusion assembly and the plurality of split rings.