Reservoir Tool for Packer Setting

Abstract

An external casing packer with a packer element is fashioned from materials that physically expand (“swell”) in response to contact by an appropriate swelling fluid. In preferred embodiments, the packer element is fashioned of a swellable elastomer, and the swelling fluid is an oil or water-based fluid that is effective to swell the particular elastomer used.

1 . An packer device for providing a seal between a string of casing and a borehole wall, the device comprising:
 a packer element substantially formed of a material that swells in response to contact by a swelling fluid;   a fluid reservoir containing a swelling fluid that causes the packer element to swell upon contact; and   a distribution conduit for transmitting the swelling fluid from the reservoir to the packer element.   
   
   
       2 . The packer device of  claim 1  wherein the distribution conduit further comprises a nozzle that is disposed within the packer element, the nozzle having a plurality of fluid openings. 
   
   
       3 . The packer device of  claim 1  wherein the swelling fluid comprises a water-based fluid. 
   
   
       4 . The packer device of  claim 1  wherein the swelling fluid comprises an oil-based fluid. 
   
   
       5 . The packer device of  claim 1  wherein the packer element is substantially formed of a swellable elastomer. 
   
   
       6 . The packer device of  claim 1  wherein there is a plurality of fluid reservoirs. 
   
   
       7 . The packer device of  claim 1  wherein the fluid reservoir further comprises:
 a reservoir body containing the swelling fluid;   an opening in the reservoir body; and   a piston moveably disposed within the reservoir body between the opening and the swelling fluid, the piston forming a fluid seal against the reservoir body and moveable in response to annular fluid pressure.   
   
   
       8 . A packer device for providing a seal between a string of casing and a borehole wall, the device comprising:
 a central packer mandrel for incorporation into the string of casing;   a packer element radially surrounding the mandrel and substantially formed of an elastomeric material that swells in response to contact by a swelling fluid;   a fluid reservoir containing a swelling fluid that causes the packer element to swell upon contact; and   a distribution conduit for transmitting the swelling fluid from the reservoir to the packer element.   
   
   
       9 . The packer device of  claim 8  wherein the fluid reservoir further comprises:
 a reservoir body containing the swelling fluid;   an opening in the reservoir body; and   a piston moveably disposed within the reservoir body between the opening and the swelling fluid, the piston forming a fluid seal against the reservoir body and moveable in response to annular fluid pressure.   
   
   
       10 . The packer device of  claim 8  wherein the distribution conduit further comprises a nozzle that is disposed within the packer element, the nozzle having a plurality of fluid openings. 
   
   
       11 . The packer device of  claim 8  wherein the swelling fluid comprises a water-based fluid. 
   
   
       12 . The packer device of  claim 8  wherein the swelling fluid comprises an oil-based fluid. 
   
   
       13 . A method of forming a packer seal between a string of casing and a surrounding well bore wall, the method comprising the steps of:
 integrating a packer device into the string of casing, the packer device comprising:
 a) a packer element substantially formed of an elastomeric material that swells in response to contact by a swelling fluid; and 
 b) a fluid reservoir containing a swelling fluid that causes the packer element to swell upon contact; 
   disposing the string of casing and packer device into a wellbore;   flowing the swelling fluid from the fluid reservoir to the packer element to cause the packer element to swell and form a seal against the surrounding well bore wall.   
   
   
       14 . The method of  claim 13  wherein the step of flowing the swelling fluid from the fluid reservoir to the packer element further comprises urging a piston against the swelling fluid within the fluid reservoir. 
   
   
       15 . The method of  claim 14  wherein the piston is urged against the swelling fluid in response to increased fluid pressure within an annulus surrounding the string of casing.