Actuator Assembly for Tubular Expansion

Abstract

A hydraulically powered downhole tool includes a tool mandrel ( 20 ) having an interior bore ( 22 ), and a plurality of pistons ( 26 ) each axially movable relative to the tool mandrel and mechanically interconnected by an outer sleeve ( 24 ) exterior of the tool mandrel. A plurality of mandrel sections and a plurality of outer sleeve sections each have a lower end for interconnection with an upper end of a corresponding member. A retainer ( 28 ), ( 29 ) is provided for supporting each outer sleeve section above a respective lower sleeve section, thereby exposing mandrel sections for vertical assembly.

1 . A hydraulically powered downhole tool for axially moving an expander in a well to radially expand a downhole tubular, comprising:
 a tool mandrel axially secured to the expander, the tool mandrel including a plurality of mandrel sections each having a lower end for interconnection with an upper end of another tool mandrel section;   a plurality of pistons each axially movable relative to the tool mandrel and mechanically interconnected by an outer sleeve exterior of the tool mandrel;   one or more slips supported by the outer sleeve to temporarily fix an axial position of the outer sleeve in the well;   the outer sleeve including the plurality of outer sleeve sections each having a lower end for interconnection to an upper end of another outer sleeve section; and   a retainer for supporting an upper outer sleeve section axially above a lower outer sleeve section, thereby exposing upper and lower mandrel sections for assembly, the upper outer sleeve section being axially lowered over the assembled upper and lower mandrel sections for connection with the lower outer sleeve section.   
   
   
       2 . A downhole tool as defined in  claim 1 , wherein hydraulic fluid is supplied to the plurality of pistons through a workstring having an interior in fluid communication with an interior bore in the tool mandrel. 
   
   
       3 . A downhole tool as defined in  claim 1 , wherein the one or more slips include a plurality of circumferentially spaced slips for engaging an inner wall of the downhole tubular in the well. 
   
   
       4 . A downhole tool as defined in  claim 1 , further comprising:
 another plurality of pistons each axially movable relative to the outer sleeve and mechanically interconnected to the tool mandrel.   
   
   
       5 . A downhole tool as defined in  claim 1 , wherein the tool mandrel includes upper and lower sections interconnected by a threaded pin and box connection. 
   
   
       6 . A downhole tool as defined in  claim 1 , wherein the outer sleeve includes upper and lower sections interconnected by a threaded connection. 
   
   
       7 . A downhole tool as defined in  claim 1 , wherein the retainer comprises threads secured to the mandrel; and
 through ports in the mandrel supply fluid pressure to the plurality of pistons.   
   
   
       8 . A downhole tool as defined in  claim 1 , wherein each of the one or more slips and the outer sleeve include cam portions to force the slips radially outward in response to axial movement of the tool mandrel relative to the outer sleeve. 
   
   
       9 . A downhole tool as defined in  claim 1 , wherein the tool is assembled with a substantially vertical assembly axis at a well site. 
   
   
       10 . A hydraulically powered downhole tool comprising:
 a tool mandrel having an interior bore;   a plurality of pistons each axially movable relative to the tool mandrel and mechanically interconnected by an outer sleeve exterior of the tool mandrel;   another plurality of pistons each axially movable relative to the outer sleeve and mechanically interconnected to the tool mandrel;   a work string supplying hydraulic fluid to the plurality of pistons and the another plurality of pistons through an interior of the work string in fluid communication with the interior bore in the tool mandrel;   the tool mandrel including a plurality of mandrel sections each having a lower end for interconnection with an upper end of another tool mandrel section;   the outer sleeve including the plurality of outer sleeve sections each having a lower end for interconnection to an upper end of another outer sleeve section; and   a retainer for supporting an upper outer sleeve section axially above a respective lower outer sleeve section, thereby exposing upper and lower mandrel sections for assembly, the upper outer sleeve section being axially lowered over the assembled upper and lower mandrel sections connection with the respective lower outer sleeve section.   
   
   
       11 . A downhole tool as defined in  claim 10 , wherein the tool mandrel includes upper and lower sections interconnected by a threaded pin and box connection. 
   
   
       12 . A downhole tool as defined in  claim 10 , wherein the outer sleeve includes upper and lower sections interconnected by a threaded connection. 
   
   
       13 . A downhole tool as defined in  claim 10 , wherein the retainer comprises a latch to temporarily secure an axial position of an outer sleeve section with respect to the tool mandrel. 
   
   
       14 . A downhole tool as defined in  claim 10 , wherein through ports in the mandrel supply fluid pressure to the plurality of pistons. 
   
   
       15 . A downhole tool as defined in  claim 10 , further comprising:
 a plurality of circumferentially spaced slips supported by the outer sleeve for engaging the downhole tubular in the well to temporarily fix an axial position of the outer sleeve in the well.   
   
   
       16 . A method of assembling a hydraulically powered downhole tool at a well site, comprising:
 providing a tool mandrel having an interior bore;   providing a plurality of pistons each axially movable relative to the tool mandrel and mechanically interconnected by an outer sleeve exterior of the tool mandrel;   the tool mandrel including a plurality of mandrel sections each having a lower end for interconnection with an upper end of another tool mandrel section;   the outer sleeve including a plurality of outer upper sleeve sections each having a lower end for interconnection to an upper end of an outer lower sleeve section;   temporarily supporting each of the outer sleeve sections axially above a respective lower outer sleeve section;   thereafter interconnecting two mandrel section;   thereafter axially lowering the outer sleeve section over the interconnected mandrel section; and   thereafter assembling the outer sleeve section and the outer lower sleeve section.   
   
   
       17 . A method as defined in  claim 16 , further comprising:
 supplying hydraulic fluid to the plurality of pistons through a workstring having an interior in fluid communication with the interior bore in the tool mandrel.   
   
   
       18 . A method as defined in  claim 16 , wherein the tool mandrel includes upper and lower sections interconnected by a threaded pin and box connection. 
   
   
       19 . A method as defined in  claim 16 , wherein threads on an exterior surface of the mandrel temporarily supports a respective outer sleeve section. 
   
   
       20 . A method as defined in  claim 16 , further comprising:
 supporting one or more slips on the outer sleeve to temporarily fix an axial position of the outer sleeve in the well.