Method for removing a consumable downhole tool

• US 8,272,446 B2
• Filed: 11/10/2011
• Issued: 09/25/2012
• Est. Priority Date: 06/08/2006
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Swor, Loren C., Starr, Phillip M., Smith, Don R., Wilkinson, Brian K.
• Primary Examiner(s): COY, NICOLE A
• Application Number:
  US13/293,557
• Publication Number:
  US 20120048572A1
• Time in Patent Office: 320 Days
• Field of Search: 166/58, 166/59, 166/63, 166/228, 166/243, 166/376, 166/377
• US Class Current: 166/376
• CPC Class Codes: E21B 17/06 Releasing-joints, e.g. safety joints
• CPC Class Codes: E21B 23/06 for setting packers
• CPC Class Codes: E21B 29/02 by explosives or by thermal or chemical means freeing stuck objects by explosives E21B31/002
• CPC Class Codes: E21B 31/002 Destroying the objects to be fished, e.g. by explosive means

Abstract

A method for removing a downhole tool from a well bore comprises consuming at least a portion of the downhole tool within the well bore via exposure of the tool to heat and a source of oxygen. Another method of removing a downhole tool from a well bore comprises exposing the downhole tool to heat and a source of oxygen in situ within the well bore to desirably consume at least a portion of the tool within the well bore.

Claims

1. A method for removing a downhole tool from a wellbore comprising:

conveying the downhole tool comprising a flexible sealing element into the wellbore using a work string;

engaging the sealing element to a wellbore wall, wherein the sealing element substantially prevents a fluid flow around the downhole tool in at least one direction through the wellbore;

disconnecting the downhole tool from the work string;

consuming at least a portion of the downhole tool within the wellbore via exposure of the tool to heat and a source of oxygen, wherein consuming at least a portion of the downhole tool allows the sealing element to disengage the wellbore wall, wherein the downhole tool fails structurally while or after the portion of the downhole tool is consumed; and

further comprising an additional step comprising at least one of;

applying a load to the downhole tool to aid in the structural failure;

allowing the downhole tool to fall to the bottom of the wellbore;

or

removing the downhole tool from the wellbore.

2. The method of claim 1 wherein consuming comprises burning.

3. The method of claim 1 wherein the portion comprises a metal.

4. The method of claim 3 wherein the metal is magnesium.

5. The method of claim 4 wherein consuming comprises converting the magnesium metal to magnesium oxide.

6. The method of claim 1 further comprising igniting a fuel load to produce the heat and source of oxygen.

7. The method of claim 6 wherein the fuel load comprises a flammable, non-explosive solid.

8. The method of claim 6 wherein the fuel load comprises thermite.

9. The method of claim 8 wherein the heat and oxygen source are produced by the burning of thermite.

10. The method of claim 6 wherein igniting comprises:

triggering a firing mechanism; and

activating a heating source.

11. The method of claim 10 wherein triggering the firing mechanism comprises:

setting a device to activate the heating source when pre-defined conditions are met.

12. The method of claim 11 wherein the pre-defined conditions comprise elapsed time, temperature, pressure, or any combination thereof.

13. The method of claim 12 wherein the device comprises an electronic timer, a mechanical timer, or a spring-wound timer.

14. The method of claim 13 wherein the timer is programmable to activate the heating source when the pre-defined conditions are met.

15. The method of claim 12 wherein the device comprises a pressure-actuated firing head.

16. The method of claim 10 wherein the firing mechanism is disposed on the tool.

17. The method of claim 10 wherein the firing mechanism is lowered to the tool on a work string.

18. The method of claim 10 wherein the heating source is disposed on the tool.

19. The method of claim 10 wherein the heating source is lowered to the tool on a work string.

20. The method of claim 6 wherein the fuel load does not contact the wellbore wall.

21. The method of claim 1, wherein the additional step is applying a load to the downhole tool to aid in the structural failure.

22. The method of claim 21 wherein the load comprises a pressure load, a mechanical load, or a combination thereof.

23. The method of claim 1 further comprising releasing the downhole tool from engagement with a wall of the wellbore.

24. The method of claim 1, wherein the additional step is allowing the downhole tool to fall to the bottom of the wellbore.

25. The method of claim 1, wherein the additional step is removing the downhole tool from the wellbore.

26. The method of claim 1 wherein the downhole tool is a frac plug, a bridge plug, a packer, or a wellbore zonal isolation device.

27. The method of claim 1 wherein the downhole tool is substantially free of any connection to the surface when the downhole tool is consumed.

28. The method of claim 1 further comprising:

allowing a fluid to flow through the downhole tool.

29. The method of claim 1 wherein the heat is produced in a substantially radial direction at a plurality of locations spaced longitudinally apart along the downhole tool.

30. The method of claim 1 wherein downhole tool prevents downward fluid flow through the wellbore.

31. The method of claim 1 further comprising flowing the fluid through the wellbore.

32. The method of claim 1 wherein the downhole tool substantially prevents a fluid flow in at least one direction through the wellbore.

33. The method of claim 1 wherein the portion comprises magnesium, and further comprising igniting a fuel load to produce the heat and source of oxygen, wherein the fuel load comprises thermite.