Downhole tools comprising oil-degradable sealing elements

Patent metadata

Field	Value
Publication number	US-2016258240-A1
Application number	US-201414433304-A
Country	US
Kind code	A1
Filing date	May 7, 2014
Priority date	May 7, 2014
Publication date	Sep 8, 2016
Grant date	—

Abstract

Downhole tools comprising a body, wherein at least a portion of the body is degradable when exposed to a wellbore environment; and at least one oil-degradable sealing element composed of an oil-degradable elastomer, wherein the oil-degradable sealing element degrades in the wellbore environment. The oil-degradable elastomer is selected from the group consisting of an oil-degradable natural rubber, an oil-degradable synthetic rubber, and any combination thereof.

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 oil-degradable sealing element composed of an oil-degradable elastomer, wherein the oil-degradable sealing element degrades in the wellbore environment.

2 . The downhole tool of claim 1 , wherein the oil-degradable elastomer is selected from the group consisting of an oil-degradable natural rubber, an oil-degradable synthetic rubber, and any combination thereof.

3 . The downhole tool of claim 2 , wherein the oil-degradable synthetic rubber is selected from the group consisting of ethylene propylene diene M-class rubber, isoprene rubber, isobutylene rubber, polyisobutene rubber, styrene-butadiene rubber, silicone rubber, ethylene propylene rubber, butyl rubber, norbornene rubber, polynorbornene rubber, a block polymer of styrene, a block polymer of styrene and butadiene, a block polymer of styrene and isoprene, a polyepichlorohydrin, a copolymer of ethylene oxide/polyepichlorohydrin, a terpolymers of epichlorohydrin/ethylene oxide/allyl glycidyl either, and any combination thereof.

4 . The downhole tool of claim 1 , wherein the body is degradable when exposed to at least one of an aqueous fluid, a wellbore temperature of at least about 93° C., and a hydrocarbon fluid in the wellbore environment.

5 . The downhole tool of claim 4 , wherein the aqueous fluid in the wellbore environment further comprises an ionic salt.

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

7 . The downhole tool of claim 6 , wherein the wellbore zonal isolation device is selected from the group consisting of a frac plug, a bridge plug, or a packer.

8 . The downhole tool of claim 1 , wherein the oil-degradable sealing element is at least partially encapsulated in a second material, and wherein the second material delays degradation of the oil-degradable sealing element.

9 . 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 oil-degradable sealing element.

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

11 . The downhole tool of claim 1 , wherein the oil-degradable elastomer further comprises a thermoplastic polymer embedded therein.

12 . A method comprising:
installing a downhole tool in a wellbore, wherein the downhole tool comprises a body and at least one oil-degradable sealing element composed of an oil-degradable elastomer, and
wherein at least a portion of the body is degradable when exposed to the wellbore environment and the oil-degradable sealing element degrades in the wellbore environment;
fluidly sealing two sections of the wellbore with the oil-degradable sealing element of the downhole tool, the oil-degradable sealing element capable of holding a differential pressure; performing a downhole operation; and degrading at least a portion of the oil-degradable sealing such that the oil-degradable sealing element no longer is capable of holding the differential pressure.

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

14 . The method of claim 12 , wherein the body is degradable when exposed to at least one of an aqueous fluid, a wellbore temperature of at least about 93° C., and a hydrocarbon fluid in the wellbore environment.

15 . The method of claim 14 , wherein the aqueous fluid further comprises an ionic salt.

16 . The method of claim 12 , wherein the oil-degradable elastomer is selected from the group consisting of an oil-degradable natural rubber, an oil-degradable synthetic rubber, and any combination thereof.

17 . The method of claim 12 , wherein the oil-degradable sealing element is at least partially encapsulated in a second material, and wherein the second material delays degradation of the oil-degradable sealing element.

18 . The method of claim 12 , wherein the portion of the body that is degradable releases an accelerant during degradation, and wherein the accelerant accelerates the degradation of the oil-degradable sealing element.

19 . The method of claim 12 , wherein the oil-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 . The method of claim 12 , wherein the oil-degradable elastomer further comprises a thermoplastic polymer embedded therein.

21 . The method of claim 12 , wherein the downhole operation is a fluid injection operation.

22 . The method of claim 21 , wherein the fluid injection operation is a hydraulic fracturing operation.

23 . 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 oil-degradable sealing element composed of an oil-degradable elastomer and the oil-degradable sealing element is capable of holding a differential pressure,
wherein at least a portion of the body is degradable when exposed to the wellbore environment and the oil-degradable sealing element degrades in the wellbore environment.

24 . The system of claim 23 , wherein the oil-degradable elastomer is selected from the group consisting of an oil-degradable natural rubber, an oil-degradable synthetic rubber, and any combination thereof.

25 . The system of claim 23 , wherein the oil-degradable sealing element is at least partially encapsulated in a second material, and wherein the second material delays degradation of the oil-degradable sealing element.

26 . The system of claim 23 , wherein the portion of the body that is degradable releases an accelerant during degradation, and wherein the accelerant accelerates the degradation of the oil-degradable sealing element.

27 . The system of claim 23 , wherein the oil-degradable sealing element releases an accelerant during degradation, and wherein the accelerant accelerates the degradation of the portion of the body that is degradable.

28 . The system of claim 23 , wherein the oil-degradable elastomer further comprises a thermoplastic polymer embedded therein.

Assignees

• Halliburton Energy Services Inc

Inventors

• Fripp Michael Linley
• Murphree Zachary
• Walton Zach
• Smith Charles Timothy

Classifications

• E21B33/12 Primary

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

• C09K8/5083

  obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• E21B33/128

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

• C09K8/5086

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• E21B43/26

  by forming crevices or fractures · CPC title