Degradable layer for temporarily protecting a seal

Abstract

A packer arrangement for forming a seal between an inner member and an outer tubular string in a borehole includes an outer tubular string member having a chamber portion; and a packer device disposed at least partially within the chamber portion and including a sealing element for forming a seal against an inner member, the packer device including a degradable layer, the degradable layer temporarily and at least partially protecting the sealing element and method of establishing a seal.

1 . A packer arrangement for forming a seal between an inner member and an outer tubular string in a borehole, the packer arrangement comprising:
 an outer tubular string member having a chamber portion; and   a packer device disposed at least partially within the chamber portion and including a sealing element for forming a seal against an inner member, the packer device including a degradable layer, the degradable layer temporarily and at least partially protecting the sealing element.   
     
     
         2 . The packer arrangement of  claim 1  further comprising a setting member for selectively actuating the sealing element between set and unset positions. 
     
     
         3 . The packer arrangement of  claim 1  wherein the sealing element comprises an elastomeric seal. 
     
     
         4 . The packer arrangement of  claim 1  wherein the sealing element comprises a metallic seal. 
     
     
         5 . The packer arrangement of  claim 2  further comprising a locking mechanism for securing the setting member such that the sealing element is maintained in the set position. 
     
     
         6 . The packer arrangement of  claim 5  wherein the locking mechanism comprises a body lock ring. 
     
     
         7 . The packer arrangement of  claim 5  wherein the setting member comprises:
 a compression member that is axially moveable within the chamber portion; and 
 an engagement profile for selectively securing the compression member to a setting tool component. 
 
     
     
         8 . The packer arrangement of  claim 7  wherein the setting member comprises a camming member that is axially moveable within the chamber portion between a first position wherein the sealing element is unset and a second position wherein the camming member urges the sealing element radially inwardly by camming toward the set position. 
     
     
         9 . The packer arrangement of  claim 7  wherein the setting member comprises:
 a generally cylindrical compression member having a helical interface with the outer tubular string member such that rotation of the compression member results in movement of the compression member axially within the outer tubular string member. 
 
     
     
         10 . The packer arrangement of  claim 1  wherein the degradable layer is disposed in the chamber portion. 
     
     
         11 . The packer arrangement of  claim 2  wherein the degradable layer is removed before the sealing element is actuated. 
     
     
         12 . The packer arrangement of  claim 1 , wherein the degradable layer is disposed radially inwardly of the sealing element. 
     
     
         13 . The packer arrangement of  claim 1 , further comprising a seal engagement member having a plurality of radially extending pips for engaging into the seal element. 
     
     
         14 . The packer arrangement of  claim 2  wherein the setting member comprises a hydraulically-actuated setting piston. 
     
     
         15 . The packer arrangement of  claim 1  wherein:
 the packer device comprises a sealing element within the chamber portion; and 
 the inner tubular string includes a ductile tube that is expandable radially outwardly to form a sealing engagement with the sealing element within the chamber portion. 
 
     
     
         16 . The packer arrangement of  claim 15  wherein the sealing element comprises an elastomeric sealing element. 
     
     
         17 . The packer arrangement of  claim 15  wherein the sealing element comprises a metallic sealing element and the sealing engagement of the ductile tube and the sealing element forms a biting retention to withstand high axial tubing loads. 
     
     
         18 . The packer arrangement of  claim 15  wherein the ductile tube is expanded radially outwardly by hydraulic inflation. 
     
     
         19 . The packer arrangement of  claim 15  wherein the ductile tube is expanded radially outwardly by mechanical swaging. 
     
     
         20 . A borehole production system comprising:
 an outer tubular string defining a central bore;   a packer device associated with the outer tubular string, the packer device including a sealing element actuatable between set and unset positions, the packer device including a degradable layer for temporarily and at least partially protecting the sealing element, wherein the sealing element of the packer device is moved radially inwardly to engage an inner tubular string for forming a seal against the inner tubular string.   
     
     
         21 . The borehole production system of  claim 20  further comprising a setting member for selectively actuating the sealing element from the unset position to the set position. 
     
     
         22 . The borehole production system of  claim 21  wherein the setting member comprises:
 a compression member that is axially moveable within the chamber portion; and 
 an engagement profile for selectively securing the compression member to a setting tool component. 
 
     
     
         23 . The borehole production system of  claim 22  wherein the setting member comprises a generally cylindrical compression member having a helical interface with the outer tubular string member such that rotation of the compression member results in movement of the compression member axially within the outer tubular string member. 
     
     
         24 . The borehole production system of  claim 23  further comprising an inner tubular string for production of hydrocarbons against which the packer device is set. 
     
     
         25 . The borehole production system of  claim 23  wherein the sealing element comprises an elastomeric seal. 
     
     
         26 . The borehole production system of  claim 23  wherein the sealing element comprises a non-elastomeric seal. 
     
     
         27 . The borehole production system of  claim 23  wherein the sealing element comprises a metallic seal member. 
     
     
         28 . The borehole production system of  claim 23  further comprising a locking mechanism for securing the setting member such that the sealing element is maintained in the set position. 
     
     
         29 . The borehole production system of  claim 28  wherein the locking mechanism comprises a body lock ring assembly. 
     
     
         30 . A method of establishing a seal within a borehole between an outer tubular string member and an inner tubular string member, comprising the steps of:
 disposing an outer tubular string within a borehole, the outer tubular string containing an outer tubular string member having an enlarged diameter chamber portion with a packer device residing at least partially within the chamber portion, the packer device being actuatable between an unset position and a set position and including a degradable layer for temporarily and at least partially protecting the packer device;   disposing an inner tubular string within the outer tubular string;   actuating the packer device from the unset position to the set position to create a seal between the outer and inner tubular strings.   
     
     
         31 . The method of  claim 30  wherein the step of actuating the packer device comprises axially compressing a packer element to cause the packer element to be expanded radially inwardly against the inner tubular string. 
     
     
         32 . The method of  claim 30  wherein the step of actuating the packer device comprises urging a compression member axially against a sealing member to cause the sealing member to expand axially inwardly against the inner tubular string. 
     
     
         33 . The method of  claim 32  wherein the step of urging the compression member axially against the sealing member comprises:
 engaging an engagement profile on the compression member with a portion of the inner tubular string, and 
 moving the inner tubular string axially with respect to the outer tubular string to cause the compression member to be urged against the sealing member. 
 
     
     
         34 . The method of  claim 33  further comprising securing the packer device in a set position with a locking mechanism. 
     
     
         35 . The method of  claim 30  wherein the degradable layer is disposed in the chamber portion. 
     
     
         36 . The method of  claim 30  further comprising removing the degradable layer before the step of actuating packer device.