Extrusion gap reduction device and method for reducing an extrusion gap

Abstract

An extrusion gap reduction device includes an outer housing; an inner housing movably disposed relative to the outer housing. A plurality of petals movably connected to the inner housing. One or more of the plurality of petals including a follower responsive to a cam surface of the outer housing.

1 . An extrusion gap reduction device comprising:
 an outer housing;   an inner housing movably disposed relative to the outer housing; and   a plurality of petals movably connected to the inner housing, one or more of the plurality of petals including a follower responsive to a cam surface of the outer housing.   
     
     
         2 . An extrusion gap reduction device as claimed in  claim 1  wherein the inner housing is rotatably movable relative to the outer housing. 
     
     
         3 . An extrusion gap reduction device as claimed in  claim 1  wherein the plurality of petals are rotatably movable relative to the inner housing. 
     
     
         4 . An extrusion gap reduction device as claimed in  claim 1  wherein the inner housing further includes a limit groove arranged to limit movement of the outer housing relative to the inner housing. 
     
     
         5 . An extrusion gap reduction device as claimed in  claim 4  wherein the limit groove is arranged circumferentially in the inner housing. 
     
     
         6 . An extrusion gap reduction device as claimed in  claim 4  wherein the outer housing includes a lug arranged to interact with the limit groove. 
     
     
         7 . An extrusion gap reduction device as claimed in  claim 1  wherein at least one of the plurality of petals has an arcuate edge. 
     
     
         8 . An extrusion gap reduction device as claimed in  claim 7  wherein the arcuate edge has an arc length sufficient to span a distance between a next adjacent petal of the plurality of petals on each side of the at least one petal. 
     
     
         9 . An extrusion gap reduction device as claimed in  claim 1  wherein at least one of the petals has a first region extending in a general direction and a second region extending in another general direction having an angle relative to the first general direction. 
     
     
         10 . An extrusion gap reduction device as claimed in  claim 9  wherein the angle is formed by the first region having a radius that is about the same radius of the outer housing and a second region having a radius that is about the same radius of an inside diameter of a tubular in which the device is to be set. 
     
     
         11 . An extrusion gap reduction device as claimed in  claim 1  wherein one or more of the petals are connected to the inner housing via a pivot pin. 
     
     
         12 . An extrusion gap reduction device as claimed in  claim 1  wherein one or more of the followers is a pin. 
     
     
         13 . A packer system comprising:
 an element; and   at least one extrusion gap reduction device as claimed in  claim 1 .   
     
     
         14 . A packer system as claimed in  claim 13  wherein the at least one extrusion gap reduction device is two devices disposed at opposite axial ends of the element. 
     
     
         15 . A borehole system including the packer system of  claim 13  deployed therein. 
     
     
         16 . An extrusion gap reduction device comprising:
 an outer housing;   an inner housing movably disposed relative to the outer housing; and   a plurality of petals movably connected to one of the inner housing and or the outer housing, one or more of the plurality of petals including a follower responsive to a cam surface of the other of the inner housing or the outer housing.