Support cone for retrievable packer

Patent metadata

Field	Value
Publication number	US-9534462-B2
Application number	US-201414466654-A
Country	US
Kind code	B2
Filing date	Aug 22, 2014
Priority date	Aug 22, 2014
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

Opposed cones for slips on a packer have an annular undercut in general alignment with the end of the cone that has the slip ramp. The undercut faces the mandrel on which the cones can be driven together to radially extend the slips. A high modulus insert sleeve is interference fitted to the undercut. This results in the cone exterior surface being in hoop stress tension before the slips are set. Once the slips are set and a reaction load comes radially back from the surrounding tubular into which the slips have extended there is a tendency for the reaction force to put the exterior surface of the cones into compressive hoop stress. The initial tensile hoop stress from the sleeve placement acts to at least in part offset the reaction force tending to create compressive hoop stress. The net loading and deflection of the mandrel is minimized.

First claim

I claim:

1. A tool for subterranean use, comprising:
a mandrel;
an anchoring assembly further comprising at least one cone selectively movable between at least one slip and said mandrel and at least one sleeve fitted to said cone in a manner to put a tensile hoop stress on at least one exterior surface of said cone before said slip is moved against a surrounding tubular.

2. The tool of claim 1 , further comprising:
a radially extendable seal mounted to said mandrel to selectively engage a surrounding tubular.

3. The tool of claim 1 , wherein:
said sleeve contacting said mandrel and said cone during loading.

4. The tool of claim 1 , wherein:
said sleeve is stiffer than said cone or has a higher compressive yield strength than the cone.

5. The tool of claim 1 , wherein:
said sleeve is mounted in an undercut between said cone and said mandrel.

6. The tool of claim 5 , wherein:
said undercut is in said cone.

7. The tool of claim 1 , wherein:
said sleeve is rotationally locked to said cone.

8. The tool of claim 1 , wherein:
said sleeve underlies at least a ramp on said cone.

9. The tool of claim 8 , wherein:
said sleeve extends from a bottom of said ramp and axially beyond a top of said ramp for a length at least as long as the axial length of said ramp.

10. The tool of claim 1 , wherein:
said sleeve has a modulus of elasticity of at least 60E6 PSI.

11. The tool of claim 1 , wherein:
said at least one cone comprises two spaced apart opposed cones with ramps facing each other;
said at least one sleeve comprises two sleeves, each of said cones being associated with one of said sleeves.

12. The tool of claim 1 , wherein:
said sleeve is no more than a quarter the maximum thickness of said cone.

13. The tool of claim 1 , wherein:
said sleeve reduces stress on the mandrel when said slip engages the surrounding tubular by transmitting force to a larger area on said mandrel that has been reduced by the initial tensile hoop stress on said cone initially applied by said sleeve.

14. A tool for subterranean use, comprising:
a mandrel;
an anchoring assembly further comprising at least one cone selectively movable between at least one slip and said mandrel and at least one a sleeve fitted to said cone in a manner to put a tensile hoop stress on at least one exterior surface of said cone before said slip is moved against a surrounding tubular;
said sleeve is interference fit within said cone.

15. A tool for subterranean use, comprising:
a mandrel;
an anchoring assembly further comprising at least one cone selectively movable between at least one slip and said mandrel and at least one a sleeve fitted to said cone in a manner to put a tensile hoop stress on at least one exterior surface of said cone before said slip is moved against a surrounding tubular;
said tensile hoop stress created by placement of said sleeve is offset with compressive hoop stress from a reaction force from the surrounding tubular when said slip is forced against the surrounding tubular by said cone.

16. The tool of claim 15 , wherein:
said sleeve is stiffer than said cone or has a higher compressive yield strength than the cone.

17. The tool of claim 16 wherein:
said sleeve is mounted in an undercut between said cone and said mandrel.

18. The tool of claim 17 , wherein:
said undercut is in said cone.

19. The tool of claim 18 , wherein:
said sleeve is rotationally locked to said cone.

20. The tool of claim 15 , wherein:
said sleeve is interference fit within said cone.

21. A tool for subterranean use, comprising:
a mandrel;
an anchoring assembly further comprising at least one cone selectively movable between at least one slip and said mandrel and at least one a sleeve fitted to said cone in a manner to put a tensile hoop stress on at least one exterior surface of said cone before said slip is moved against a surrounding tubular;
said sleeve has a higher coefficient of thermal expansion than said cone.

Assignees

• Baker Hughes Inc

Inventors

• Hayter Steven R

Classifications

• E21B23/06

  for setting packers · CPC title

• E21B23/065 Primary

  setting tool actuated by explosion or gas generating means · CPC title