Swellable Seal with Backup

Abstract

A well seal assembly for use in a seal groove of a well component. The seal assembly including a swellable elastomer seal to reside in the seal groove. The swellable elastomer seal responsive to expand when in contact with a specified fluid. A backup member is provided to reside in the seal groove, axially between the swellable elastomer seal and an axial end wall of the seal groove. The backup ring includes an undulation that, when axially compressed, expands the backup member.

What is claimed is: 
     
         1 . A well seal assembly for use in a seal groove of an elongate well component, comprising:
 a swellable elastomer seal to reside in the seal groove, the swellable elastomer seal responsive to expand when in contact with a specified fluid; and   a backup member to reside in the seal groove axially between the swellable elastomer seal and an axial end wall of the seal groove, the backup member comprising an undulation that, when axially compressed, expands the backup member.   
     
     
         2 . The well seal assembly of  claim 1 , where the backup member comprises a plurality of axial undulations distributed evenly around the backup member. 
     
     
         3 . The well seal assembly of  claim 1 , where the backup member comprises a wave spring. 
     
     
         4 . The well seal assembly of  claim 1 , where the swellable elastomer seal swells axially when in contact with the specified fluid and axially compresses the backup member. 
     
     
         5 . The well seal assembly of  claim 1 , where the well component comprises a first tubular and the seal groove is annular to encircle the first tubular, and the first tubular of the well component is insertable into a specified second tubular; and
 where the swellable elastomer seal is annular to encircle the first tubular and swellable to abut and seal against the second tubular.   
     
     
         6 . The well seal assembly of  claim 5 , where the backup member is annular to encircle the first tubular and expands radially, when axially compressed, to press against the second tubular. 
     
     
         7 . The well seal assembly of  claim 1 , comprising a second backup member to reside in the seal groove axially between the swellable elastomer seal and an opposite axial end wall of the seal groove. 
     
     
         8 . The well seal assembly of  claim 1 , where the backup member comprises a chamfer oriented toward the swellable elastomer seal. 
     
     
         9 . The well seal assembly of  claim 8 , where the backup member comprises parallel, opposing axial sidewalls. 
     
     
         10 . The well seal assembly of  claim 1 , where the backup member is a different, harder material than the swellable elastomer seal. 
     
     
         11 . A method, comprising:
 expanding, in response to contact with a specified fluid, a swellable elastomer seal in a seal groove of an elongate well component; and   axially compressing an undulation of a backup member in the seal groove with the swellable elastomer seal, expanding the backup member outward.   
     
     
         12 . The method of  claim 11 , where axially compressing an undulation of the backup member comprises axially compressing a plurality of axial undulations of the backup member, the undulations distributed evenly around the backup member. 
     
     
         13 . The method of  claim 11 , where axially compressing an undulation of the backup member comprises axially compressing the undulation between the seal and an axial end wall of the seal groove. 
     
     
         14 . The method of  claim 11 , comprising sealing, with the swellable elastomer seal, against a surface of a second well component; and
 supporting the swellable elastomer seal against extruding through a gap between the first mentioned well component and the second well component with the backup member.   
     
     
         15 . The method of  claim 11 , comprising axially compressing an undulation of a second backup member in the seal groove with the swellable elastomer seal, expanding the second backup member outward. 
     
     
         16 . The method of  claim 15 , comprising sealing, with the swellable elastomer seal, against a surface of a second well component; and
 supporting the swellable elastomer seal against extruding through gaps between the first mentioned well component and the second well component with the first mentioned backup member and the second backup member.   
     
     
         17 . A well device for use in a well, comprising:
 a swellable seal in a seal groove of the well device, the swellable seal responsive to swell when in contact with a fluid; and   a wave backup ring in the seal groove responsive to expand outward when axially compressed by the swellable seal.   
     
     
         18 . The well device of  claim 17 , where the wave backup ring comprises a plurality of axial undulations distributed evenly around the ring. 
     
     
         19 . The well device of  claim 17 , where the wave backup ring comprises a chamfer oriented toward the swellable seal. 
     
     
         20 . The well device of  claim 17 , comprising a second wave backup ring in the seal groove opposite the swellable seal and responsive to expand outward when axially compressed by the swellable seal.