Degradable wellbore isolation devices with degradable sealing balls

Patent metadata

Field	Value
Publication number	US-10227841-B2
Application number	US-201514784829-A
Country	US
Kind code	B2
Filing date	Jun 30, 2015
Priority date	Aug 28, 2014
Publication date	Mar 12, 2019
Grant date	Mar 12, 2019

Abstract

Downhole tools including a wellbore isolation device that provides a plurality of components including a mandrel, a packer element, and a sealing ball, wherein the mandrel defines a central flow passage that allows fluid flow in at least one direction through the wellbore isolation device, wherein at least a portion of the mandrel is composed of a degradable metal material, at least a portion of the packer element is composed of an elastomer, and at least a portion of the sealing ball is composed of a degradable substance, and wherein the degradable metal material and the degradable substance degrades upon exposure to a wellbore environment.

First claim

What is claimed is:

1. A downhole tool comprising:
a wellbore isolation device that provides a plurality of components including a mandrel, a packer element, and a sealing ball,
wherein the mandrel defines a central flow passage that allows fluid flow in at least one direction through the wellbore isolation device,
wherein at least a portion of the mandrel is composed of a slowly degradable metal material having a period for degradation in the range of from about 5 days to about 40 days, at least a portion of the packer element is composed of an elastomer, and at least a portion of the sealing ball is composed of a degradable substance,
wherein the slowly degradable metal material and the degradable substance degrades upon exposure to a wellbore environment; and
wherein the wellbore isolation device provides an inner diameter and an outer diameter, and wherein a minimum production flow area across the wellbore isolation device is selected from the group consisting of:

a first flow area across the wellbore isolation device of at least 1/25 a total flow area of a casing at a location of the wellbore isolation device within a wellbore,
a second flow area resulting from the inner diameter being at least 17% of the outer diameter, and
any combination thereof.

2. The downhole tool of claim 1 , wherein the wellbore isolation device is selected from the group consisting of a frac plug, a wellbore packer, a deployable baffle, and any combination thereof.

3. The downhole tool of claim 1 , wherein the wellbore isolation device is a frac plug and the sealing ball is a frac ball.

4. The downhole tool of claim 1 , wherein the slowly degradable metal material is selected from the group consisting of gold, a gold-platinum alloy, silver, nickel, a nickel-copper alloy, a nickel-chromium alloy, copper, a copper alloy, chromium, tin, aluminum, an aluminum alloy, iron, zinc, magnesium, a magnesium alloy, beryllium, any alloy thereof, and any combination thereof.

5. The downhole tool of claim 1 , wherein the elastomer is minimally degradable such that no more than about 50% by volume of the elastomer degrades in the wellbore environment.

6. The downhole tool of claim 1 , wherein the elastomer is a degradable elastomer that degrades in the presence of the wellbore environment.

7. The downhole tool of claim 1 , wherein the elastomer is a degradable elastomer that degrades in the presence of the wellbore environment, and the wellbore environment is selected from the group consisting of an aqueous fluid, a hydrocarbon fluid, and any combination thereof.

8. The downhole tool of claim 1 , wherein the elastomer is a degradable elastomer that degrades in the presence of the wellbore environment, the degradable elastomer selected from the group consisting of a polyurethane rubber; a polyester-based polyurethane rubber; a polyether-based polyurethane rubber; a thiol-based polymer; a thiol-epoxy polymer; a hyaluronic acid rubber; a polyhydroxobutyrate rubber; a polyester elastomer; a polyester amide elastomer; a starch-based resin; a polyethylene terephthalate polymer; a polyester thermoplastic; a polylactic acid polymer; a polybutylene succinate polymer; a polyhydroxy alkanoic acid polymer; a polybutylene terephthalate polymer; a polysaccharide; chitin; chitosan; a protein; an aliphatic polyester; poly(ε-caprolactone); a poly(hydroxybutyrate); poly(ethyleneoxide); poly(phenyllactide); a poly(amino acid); a poly(orthoester); polyphosphazene; a polylactide; a polyglycolide; a poly(anhydride); a polyepichlorohydrin; a copolymer of ethylene oxide/polyepichlorohydrin; a terpolymer of epichlorohydrin/ethylene oxide/allyl glycidyl ether; any copolymer thereof; any terpolymer thereof; and any combination thereof.

9. The downhole tool of claim 1 , wherein the degradable substance is selected from the group consisting of a degradable metal material, a degradable elastomer, a degradable glass material, and any combination thereof.

10. The downhole tool of claim 1 , wherein the degradable substance is a degradable metal material selected from the group consisting of gold, a gold-platinum alloy, silver, nickel, a nickel-copper alloy, a nickel-chromium alloy, copper, a copper alloy, chromium, tin, aluminum, an aluminum alloy, iron, zinc, magnesium, a magnesium alloy, beryllium, any alloy thereof, and any combination thereof.

11. The downhole tool of claim 1 , wherein the degradable substance is a slowly degradable metal material, rates of degradation of the slowly degradable metal materials of the mandrel and the sealing ball being in the range of from about 0.01 mg/cm 2 to about 10 mg/cm 2 per hour at 200° F. in 15% KCl brine.

12. The downhole tool of claim 1 , wherein the degradable substance is a degradable metal, rates of degradation of the degradable metal materials of the mandrel and the sealing ball being greater than about 10 mg/cm 2 per hour at 200° F. in 15% KCl brine.

13. The downhole tool of claim 1 , wherein the degradable substance is a slowly degradable metal material, rates of degradation of the slowly degradable metal materials of the mandrel and the sealing ball being in the range of from about 0.1% to about 10% loss of total mass per day at 200° F. in 15% KCl brine.

14. The downhole tool of claim 1 , wherein the degradable substance is a degradable metal material, rates of degradation of the degradable metal materials of the mandrel and the sealing ball being greater than about 10% loss of total mass per day at 200° F. in 15% KCl brine.

15. The downhole tool of claim 1 , wherein the degradable substance is a degradable elastomer selected from the group consisting of a polyurethane rubber; a polyester-based polyurethane rubber; a polyether-based polyurethane rubber; a thiol-based polymer; a thiol-epoxy polymer; a hyaluronic acid rubber; a polyhydroxobutyrate rubber; a polyester elastomer; a polyester amide elastomer; a starch-based resin; a polyethylene terephthalate polymer; a polyester thermoplastic; a polylactic acid polymer; a polybutylene succinate polymer; a polyhydroxy alkanoic acid polymer; a polybutylene terephthalate polymer; a polysaccharide; chitin; chitosan; a protein; an aliphatic polyester; poly(ε-caprolactone); a poly(hydroxybutyrate); poly(ethyleneoxide); poly(phenyllactide); a poly(amino acid); a poly(orthoester); polyphosphazene; a polylactide; a polyglycolide; a poly(anhydride); a polyepichlorohydrin; a copolymer of ethylene oxide/polyepichlorohydrin; a terpolymer of epichlorohydrin/ethylene oxide/allyl glycidyl ether; any copolymer thereof; any terpolymer thereof; and any combination thereof.

16. The downhole tool of claim 1 , wherein the degradable substance is a degradable glass material selected from the group consisting of a glass polyalkenoate, borate glass polyalkenoate, calcium phosphate glass, polylactic acid/calcium phosphate glass, phosphate glass, silica glass, and any combination thereof.

17. The downhole tool of claim 1 , wherein the minimum production flow area across the wellbore isolation device includes any fluid flow area through the central flow passage and through any other flow paths through or around the wellbore isolation device.

18. The downhole tool of claim 17 , wherein the other flow paths comprise at least one flow channel defined longitudinally through the mandrel through which fluids may flow.

19. The downhole tool of claim 1 , wherein the inner diameter comprises a diameter of the central flow passage, and the outer diameter comprises a diameter of the wellbore isolation device in an unexpanded configuration.

Assignees

• Halliburton Energy Services Inc

Inventors

• Fripp Michael Linley
• Walton Zachary William

Classifications

• E21B33/1294

  characterised by a valve, e.g. a by-pass valve · CPC title

• C22C21/00

  Alloys based on aluminium · CPC title

• E21B33/134

  Bridging plugs · CPC title

• C09K8/426 Primary

  for plugging · CPC title

• C09K8/428

  for squeeze cementing, e.g. for repairing · CPC title