Subterranean formation operations using degradable wellbore isolation devices

Patent metadata

Field	Value
Publication number	US-10125568-B2
Application number	US-201514896684-A
Country	US
Kind code	B2
Filing date	Aug 13, 2015
Priority date	Aug 28, 2014
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

Methods including introducing a frac plug into a wellbore in a subterranean formation, the frac plug comprising at least a mandrel, slips, and a packer element, wherein at least a portion of the mandrel and/or the slips is composed of a degradable alloy selected from the group consisting of a magnesium alloy, an aluminum alloy, and any combination thereof. The wellbore may be a cased wellbore or an open-hole wellbore, and wherein the slips are frictionally engaged with the casing string or the wellbore wall and the packer element is compressed against the casing or the wellbore wall to set the frac plug. One or more perforations is created within the formation and the formation is hydraulically fractured. The frac plug is at least partially degraded upon contact with an electrolyte in the wellbore before or after beginning production of a hydrocarbon.

First claim

What is claimed is:

1. A method comprising:
(a) introducing a frac plug into a wellbore in a subterranean formation, the frac plug comprising at least a mandrel, slips, and a packer element, wherein:
at least a portion of the mandrel and/or the slips is composed of a degradable alloy selected from the group consisting of a magnesium alloy, an aluminum alloy, and any combination thereof; and
at least a portion of the frac plug comprises a non-metal degradable material having a same degradation rate as the degradable alloy, the degradation rate being about 0.1% to about 10% of total mass per day at 93° C. in a 15% KCl solution;

(b) frictionally engaging the slips with a casing string in the subterranean formation;
(c) compressing the packer element against the casing string to set the frac plug;
(d) creating at least one perforation into the subterranean formation;
(e) hydraulically fracturing the subterranean formation;
(f) at least partially degrading the degradable alloy upon contact with an electrolyte in the wellbore; and
(g) producing a hydrocarbon from the subterranean formation.

2. The method of claim 1 , wherein the packer element is at least partially composed of a degradable elastomer.

3. The method of claim 1 , wherein step (f) begins before step (g) begins, or wherein step (g) begins before step (f) begins.

4. The method of claim 1 , wherein there is no wellbore intervention for purposes of removing the frac plug or debris from the frac plug from the wellbore between steps (e) and (f), and/or between steps (f) and (g).

5. The method of claim 1 , wherein there is no wellbore intervention for purposes of removing the frac plug or debris from the frac plug from the wellbore between the steps of (e) and (g), and wherein either of steps (f) or (g) begins prior to the other.

6. The method of claim 1 , wherein the packer element is compressed by stroking the mandrel on the frac plug.

7. The method of claim 1 , wherein the packer element is compressed by rupturing a frangible barrier disposed at least partially about the packer element.

8. The method of claim 1 , further comprising seating a degradable metal ball on a ball seat of the frac plug to create a fluid seal in the wellbore.

9. The method of claim 1 , further comprising seating a degradable elastomer ball on a ball seat of the frac plug to create a fluid seal in the wellbore.

10. The method of claim 1 , wherein the frac plug further comprises a component selected from the group consisting of at least one slip wedge, at least one spacer ring, a mule shoe, and any combination thereof, and wherein one or more of the components is composed of the degradable alloy.

11. A method comprising:
(a) introducing a frac plug into a wellbore in a subterranean formation, the frac plug comprising at least a mandrel, slips, and a packer element, wherein:
at least a portion of the mandrel and/or the slips is composed of a degradable alloy selected from the group consisting of a magnesium alloy, an aluminum alloy, and any combination thereof; and
at least a portion of the frac plug comprises a non-metal degradable material having a same degradation rate as the degradable alloy, the degradation rate being about 0.1% to about 10% of total mass per day at 93° C. in a 15% KCl solution;

(b) frictionally engaging the slips with a wall of the wellbore;
(c) compressing the packer element against the wall of the wellbore to set the frac plug;
(d) creating at least one perforation into the subterranean formation;
(e) hydraulically fracturing the subterranean formation;
(f) at least partially degrading the degradable alloy upon contact with an electrolyte in the wellbore; and
(g) producing a hydrocarbon from the subterranean formation.

12. The method of claim 11 , wherein the packer element is at least partially composed of a degradable elastomer.

13. The method of claim 11 , wherein step (f) begins before step (g) begins, or wherein step (g) begins before step (f) begins.

14. The method of claim 11 , wherein there is no wellbore intervention for purposes of removing the frac plug or debris from the frac plug from the wellbore between steps (e) and (f), and/or between steps (f) and (g).

15. The method of claim 11 , wherein there is no wellbore intervention for purposes of removing the frac plug or debris from the frac plug from the wellbore between the steps of (e) and (g), and wherein either of steps (f) or (g) begins prior to the other.

16. The method of claim 11 , wherein the packer element is compressed by stroking the mandrel on the frac plug.

17. The method of claim 11 , wherein the packer element is compressed by rupturing a frangible barrier disposed at least partially about the packer element.

18. The method of claim 11 , further comprising seating a degradable metal ball on a ball seat of the frac plug to create a fluid seal in the wellbore.

19. The method of claim 11 , further comprising seating a degradable elastomer ball on a ball seat of the frac plug to create a fluid seal in the wellbore.

20. The method of claim 11 , wherein the frac plug further comprises a component selected from the group consisting of at least one slip wedge, at least one spacer ring, a mule shoe, and any combination thereof, and wherein one or more of the components is composed of the degradable alloy.

Assignees

• Halliburton Energy Services Inc

Inventors

• Fripp Michael Linley
• Walton Zachary William

Classifications

• E21B33/1208

  characterised by the construction of the sealing or packing means (E21B33/1277 takes precedence) · CPC title

• E21B33/134 Primary

  Bridging plugs · CPC title

• E21B2200/08

  Down-hole devices using materials which decompose under well-bore conditions · CPC title

• E21B33/12 Primary

  Packers; Plugs (used for cementing E21B33/134, E21B33/16) · CPC title

• E21B33/128

  with a member expanded radially by axial pressure (E21B33/122, E21B33/124 take precedence) · CPC title