Expandable Sleeve

Abstract

An expandable sleeve for use in a well, comprises a tubular structure including an external sealing layer comprising a compliant material; an intermediate expandable tubular body made from a plastically deformable material; and an internal spring structure such as a helically wound spring; wherein the external sealing layer is disposed on the outer surface of the tubular body, and the internal spring structure is disposed inside the tubular body and acts so as to exert a radial force on the body when in an expanded state. Such a sleeve can be used to seal off perforations and in well completions using slotted liners or in drilling applications.

1 . An expandable sleeve for use in a well, comprising a tubular structure including: 
 an external sealing layer comprising a compliant material;    an intermediate expandable tubular body made from a plastically deformable material; and    an internal spring structure;    wherein the external sealing layer is disposed on the outer surface of the tubular body, and the internal spring structure is disposed inside the tubular body and acts so as to exert a radial force on the body when in an expanded state.    
   
   
       2 . A sleeve as claimed in  claim 1 , wherein the internal spring structure comprises a helically wound spring.  
   
   
       3 . A sleeve as claimed in  claim 2 , wherein the internal spring structure comprises a helically would wire of rectangular section.  
   
   
       4 . A sleeve as claimed in  claim 2 , wherein the internal spring structure is provided with formations that resist compression.  
   
   
       5 . A sleeve as claimed in  claim 4 , wherein the formations comprise inter-engaging teeth formed on adjacent edges of the spring windings.  
   
   
       6 . A sleeve as claimed in  claim 1 , wherein the tubular body is formed from solid metal.  
   
   
       7 . A sleeve as claimed in  claim 1 , wherein the tubular body has a corugated structure prior to expansion.  
   
   
       8 . A sleeve as claimed in  claim 1 , wherein the external sealing layer is natural or synthetic rubber.  
   
   
       9 . A sleeve as claimed in  claim 1 , further comprising an axial reinforcement structure for supporting axial load on the sleeve.  
   
   
       10 . A sleeve as claimed in  claim 9 , wherein the axial reinforcement structure is provided by a further layer located inside the intermediate layer and attached at the extremities of the sleeve.  
   
   
       11 . A method of installing an expandable sleeve as claimed in any preceding claim in a well, comprising: 
 lowering the sleeve in an unexpanded form into the well; and    expanding the sleeve such that the external layer engages the wall of the well.    
   
   
       12 . A method as claimed in  claim 11 , wherein the internal spring is installed in the tubular body in a compressed state prior to lowering the sleeve into the well.  
   
   
       13 . A method as claimed in  claim 11 , comprising lowering the tubular body into the well and lowering the spring into the tubular body after it has been lowered into the well.  
   
   
       14 . A method as claimed in  claim 13 , comprising lowering the spring into the tubular body after the tubular body has been expanded.  
   
   
       15 . A method of completing a well, comprising installing a completion string including at least one sleeve as claimed in  claim 1  in the well.  
   
   
       16 . A method as claimed in  claim 15 , wherein the completion string comprises an array of slotted liners having sleeves as claimed in  claim 1  dispersed at various locations along the array.  
   
   
       17 . A method as claimed in  claim 16 , wherein the sleeves are expanded on installation of the completion.  
   
   
       18 . A method as claimed in  claim 16 , wherein one or more of the sleeves is expanded after installation to allow production management operations to be performed in the region between the expanded sleeves.  
   
   
       19 . A method as claimed in  claim 17 , further comprising installing at least one further sleeve as claimed in  claim 1  between adjacent expanded sleeves in the completion string to isolate that region.  
   
   
       20 . A method as claimed in  claim 16 , further comprising associating axially deformable sections with at least some of the expandable sleeves so as to compensate for changes in length of the completion string on expansion of sleeves.  
   
   
       21 . A method as claimed in  claim 20 , wherein the axially deformable sections comprise circumferential or helical corrugations.  
   
   
       22 . The use of a sleeve as claimed in  claim 1  during drilling operations to stabilise the formation being drilled.