Charge case fragmentation control for gun survival

Patent metadata

Field	Value
Publication number	US-10161723-B2
Application number	US-201214648568-A
Country	US
Kind code	B2
Filing date	Dec 19, 2012
Priority date	Dec 19, 2012
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

A method for forming a perforation is disclosed. The method comprises positioning a perforating gun at a desired location in the formation. The perforating gun comprises a gun body and a charge carrier. The method further comprises disposing one or more shaped charges within the charge carrier. The one or more shaped charges comprise an outer case, an inner liner, and an explosive material retained between the outer case and the inner liner. The outer case of the shaped charge comprises one or more predefined fracture lines. The method further comprises detonating at least one shaped charge, wherein detonating the at least one shaped charge forms one or more perforations in the formation.

First claim

What is claimed is:

1. A perforation apparatus comprising:
a perforating gun comprising a gun body and a charge carrier;
a shaped charge disposed within the charge carrier, wherein the shaped charge comprises:
an outer case;
an inner liner;
an explosive material retained between the outer case and the inner liner, wherein the outer case comprises one or more predefined fracture lines and two or more predefined elements, and wherein the two or more predefined elements are coupled to one another; and
an explosive load, wherein a material composition of the outer case, an orientation of the one or more predefined fracture lines, and a size of the two or more predefined elements is based on the explosive load and a size of one or more exit holes to be formed in the gun body.

2. The perforation apparatus of claim 1 , wherein the one or more predefined fracture lines are the boundaries between the two or more predefined elements.

3. The perforation apparatus of claim 1 , wherein the outer case is formed by a process selected from a group consisting of machining, molding, hot isostatic pressing, brazing, encapsulating, compositing, bonding, forging, sintering and laser depositing.

4. The perforation apparatus of claim 1 , wherein the outer case comprises at least one of an aluminum alloy, a steel alloy, a copper alloy, a zinc alloy, a nickel alloy, a tungsten alloy, a ceramic, and a combination thereof.

5. The perforation apparatus of claim 1 , wherein the outer case further comprises one or more grooves, and wherein the one or more predefined fracture lines are stress concentrations formed by the one or more grooves.

6. The perforation apparatus of claim 5 , wherein the one or more grooves are machined grooves, wherein the machined grooves are formed by a material removal process.

7. The perforation apparatus of claim 6 , wherein the material removal process is selected from a group consisting of cutting, chemically etching, laser ablating, abrasive jet cutting and eroding.

8. The perforation apparatus of claim 5 , wherein the one or more grooves are molded grooves, wherein the molded grooves are formed by a material forming process, and wherein the material forming process is selected from a group consisting of molding, forming, pressing and forging.

9. The perforation apparatus of claim 1 , wherein the outer case comprises a composite.

10. The perforation apparatus of claim 9 , wherein the composite further comprises a metal matrix.

11. The perforation apparatus of claim 10 , wherein the metal matrix comprises at least one of zinc, tungsten, metal alloys, or a combination thereof.

12. The perforation apparatus of claim 10 , wherein the metal matrix comprises elongated fibers of at least one of glass, carbon, Kevlar, or a combination thereof.

13. The perforation apparatus of claim 9 , wherein the composite further comprises a ceramic matrix.

14. A method for forming a perforation comprising the steps of:
positioning a perforating gun comprising a gun body and a charge carrier at a desired location in the formation;
disposing one or more shaped charges within the charge carrier, wherein the one or more shaped charges comprise:
an outer case;
an inner liner;
an explosive material retained between the outer case and the inner liner, wherein the outer case comprises one or more predefined fracture lines; and
an explosive load;

detonating at least one shaped charge, wherein detonating the at least one shaped charge forms one or more predefined fragments and one or more exit holes in the gun body, wherein the one or more predefined fragments are coupled to one another and are larger than the one or more exit holes; and
retaining the one or more predefined fragments in the gun body, wherein a material composition of the outer case, an orientation of the one or more predefined fracture lines, and a size of the one or more predefined fragments are based on the explosive load of the shaped charge and a size of the exit holes to be formed in the gun body.

15. The method of claim 14 , wherein detonating the at least one shaped charge forms one or more perforations in the formation.

16. The method of claim 15 , wherein the one or more predefined fragments are defined by the predefined fracture lines of the shaped charge.

17. The method of claim 15 , wherein impact forces on an inner wall of the gun body are minimized in part due to the size of the one or more predefined fragments.

18. The method of claim 15 , wherein a pressure rise in the perforating gun is controlled in part by a size of the one or more predefined fragments.

19. A method for forming a perforation comprising the steps of:
positioning a perforating gun comprising a gun body and a charge carrier at a desired location in the formation;
disposing one or more shaped charges within the charge carrier, wherein the one or more shaped charges comprise:
an outer case;
an inner liner;
an explosive material retained between the outer case and the inner liner, wherein the outer case comprises one or more predefined fracture lines; and
an explosive load;

detonating at least one shaped charge, wherein detonating the at least one shaped charge forms one or more perforations in the formation, one or more predefined fragments, and one or more exit holes in the gun body; and
selecting a material composition of the outer case, an orientation of the predefined fracture lines, and a size of the predefined fragments based on the explosive load of the shaped charge and a size of the exit holes in the gun body.

Assignees

• Halliburton Energy Services Inc

Inventors

• Hales John H
• Burleson John
• Rodgers John P
• Glenn Timothy S

Classifications

• F42B12/32

  the hull or case comprising a plurality of discrete bodies, e.g. steel balls, embedded therein {or disposed around the explosive charge} · CPC title

• F42B1/036

  Manufacturing processes therefor {(F42B33/0214 - F42B33/0292 take precedence)} · CPC title

• E21B43/263

  using explosives · CPC title

• F42B12/24

  with grooves, recesses or other wall weakenings {(F42B12/26, F42B12/28 take precedence)} · CPC title

• F42B1/02 Primary

  Shaped or hollow charges (blasting cartridges with cavities in the charge F42B3/08; oil winning using shaped-charge perforators E21B43/116) · CPC title