Downhole tools comprising cast degradable sealing elements

Patent metadata

Field	Value
Publication number	US-9790763-B2
Application number	US-201514890775-A
Country	US
Kind code	B2
Filing date	Jun 15, 2015
Priority date	Jul 7, 2014
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

Downhole tools including a body, wherein at least a portion of the body is degradable when exposed to a wellbore environment; and at least one degradable sealing element comprising a cast degradable elastomer, wherein at least a portion of the cast degradable sealing element degrades when exposed to the wellbore environment.

First claim

The invention claimed is:

1. A downhole tool comprising:
a body, wherein at least a portion of the body is degradable when exposed to a wellbore environment; and
at least one degradable sealing element disposed on the body, the at least one degradable sealing element comprising a thermoset cast degradable elastomer, wherein at least a portion of the thermoset cast degradable sealing element degrades when exposed to the wellbore environment.

2. The downhole tool of claim 1 , wherein the thermoset cast degradable elastomer is selected from the group consisting of a polyurethane rubber; a polyester-based polyurethane rubber; a polyether-based polyurethane rubber; a thiol-based polymer; a hyaluronic acid rubber; a polyhydroxobutyrate rubber; a polyester elastomer; a polyester amide elastomer; a starch-based resin; a polyethylene terephthalate polymer; copolymers thereof; terpolymers thereof; and any combination thereof.

3. The downhole tool of claim 1 , wherein the thermoset cast degradable elastomer is a polyurethane rubber, a polyester-based polyurethane rubber, or a polyether-based rubber.

4. The downhole tool of claim 1 , wherein the thermoset cast degradable elastomer is a thiol-based polymer.

5. The downhole tool of claim 1 , wherein the thermoset cast degradable elastomer further comprises a thermoplastic polymer embedded therein.

6. The downhole tool of claim 1 , wherein the thermoset cast degradable elastomer further comprises a reinforcing agent embedded therein.

7. The downhole tool of claim 1 , wherein the degradable sealing element is at least partially encapsulated in an encapsulating material, and wherein the encapsulating material delays degradation of the degradable sealing element.

8. The downhole tool of claim 1 , wherein the portion of the body that is degradable releases an accelerant during degradation, and wherein the accelerant accelerates the degradation of the degradable sealing element; or wherein the degradable sealing element releases an accelerant during degradation, and wherein the accelerant accelerates the degradation of the portion of the body that is degradable.

9. The downhole tool of claim 1 , wherein the downhole tool is a wellbore isolation device.

10. The downhole tool of claim 9 , wherein the wellbore isolation device is a frac plug, a bridge plug, or a packer, a wiper plug, or a cement plug.

11. A method comprising:
installing a downhole tool in a wellbore, wherein the downhole tool comprises a body and at least one degradable sealing element comprising a thermoset cast degradable elastomer disposed on the body, and
wherein at least a portion of the body and the degradable sealing element are degradable when exposed to a wellbore environment;

fluidly sealing two sections of the wellbore with the degradable sealing element of the downhole tool, the degradable sealing element capable of holding a differential pressure;
performing a downhole operation; and
degrading at least a portion of the degradable sealing element such that the degradable sealing element no longer is capable of holding the differential pressure.

12. The method of claim 11 , further comprising degrading at least a portion of the portion of the body that is degradable.

13. The method of claim 11 , wherein the thermoset cast degradable elastomer is selected from the group consisting of a polyurethane rubber; a polyester-based polyurethane rubber; a polyether-based polyurethane rubber; a thiol-based polymer; a hyaluronic acid rubber; a polyhydroxobutyrate rubber; a polyester elastomer; a polyester amide elastomer; a starch-based resin; a polyethylene terephthalate polymer; copolymers thereof; terpolymers thereof; and any combination thereof.

14. The method of claim 11 , wherein the thermoset cast degradable elastomer is a polyurethane rubber, a polyester-based polyurethane rubber, or a polyether-based rubber.

15. The method of claim 11 , wherein the thermoset cast degradable elastomer is a thiol-based polymer.

16. The method of claim 11 , wherein the thermoset cast degradable elastomer further comprises a thermoplastic polymer embedded therein.

17. The method of claim 11 , wherein thermoset cast degradable elastomer further comprises a reinforcing agent embedded therein.

18. The method of claim 11 , wherein the degradable sealing element is at least partially encapsulated in an encapsulating material, and wherein the encapsulating material delays degradation of the degradable sealing element.

19. The method of claim 11 , wherein the portion of the body that is degradable releases an accelerant during degradation, and wherein the accelerant accelerates the degradation of the degradable sealing element; or wherein the degradable sealing element releases an accelerant during degradation, and wherein the accelerant accelerates the degradation of the portion of the body that is degradable.

20. A system comprising:
a wellbore; and
a downhole tool capable of being disposed in the wellbore to fluidly seal two sections thereof, the downhole tool comprising a body and at least one degradable sealing element disposed on the body, the at least one degradable sealing element comprising a thermoset cast degradable elastomer and the degradable sealing element capable of holding a differential pressure,
wherein at least a portion of the body and at least a portion of the degradable sealing element are degradable when exposed to a wellbore environment.

21. The system of claim 20 , wherein the thermoset cast degradable elastomer is selected from the group consisting of a polyurethane rubber; a polyester-based polyurethane rubber; a polyether-based polyurethane rubber; a thiol-based polymer; a hyaluronic acid rubber; a polyhydroxobutyrate rubber; a polyester elastomer; a polyester amide elastomer; a starch-based resin; a polyethylene terephthalate polymer; copolymers thereof; terpolymers thereof; and any combination thereof.

22. The system of claim 20 , wherein the thermoset cast degradable elastomer is a polyurethane rubber, a polyester-based polyurethane rubber, or a polyether-based rubber.

23. The system of claim 20 , wherein the thermoset cast degradable elastomer is a thiol-based polymer.

24. The system of claim 20 , wherein the thermoset cast degradable elastomer further comprises a thermoplastic polymer embedded therein.

25. The system of claim 20 , wherein the thermoset cast degradable elastomer further comprises a reinforcing agent embedded therein.

26. The system of claim 20 , wherein the degradable sealing element is at least partially encapsulated in an encapsulating material, and wherein the encapsulating material delays degradation of the degradable sealing element.

27. The system of claim 20 , wherein the portion of the body that is degradable releases an accelerant during degradation, and wherein the accelerant accelerates the degradation of the degradable sealing element; or wherein the degradable sealing element releases an accelerant during degradation, and wherein the accelerant accelerates the degradation of the portion of the body that is degradable.

Assignees

• Halliburton Energy Services Inc

Inventors

• Fripp Michael Linley
• Walton Zachary William

Classifications

• E21B43/26

  by forming crevices or fractures · CPC title

• E21B33/128

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

• E21B33/1208 Primary

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

• E21B33/12 Primary

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

• E21B29/02

  by explosives or by thermal or chemical means {(freeing stuck objects by explosives E21B31/002)} · CPC title