Consistent entry hole shaped charge

Patent metadata

Field	Value
Publication number	US-10458212-B2
Application number	US-201916262627-A
Country	US
Kind code	B2
Filing date	Jan 30, 2019
Priority date	May 21, 2014
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

An apparatus and method for specialized shaped charges that perforate similar sized diameter holes regardless of the fluid gaps between the shaped charge and the casing wall. Shaped charges having three conical or frusto-conical liner sections are disclosed, where the apex liner section has a larger conical angle than the outer liner section are disclosed.

First claim

What is claimed is:

1. A method for perforating a formation comprising:
placing a perforating gun downhole at a predetermined location of a cased hole having an inner surface, placing a plurality of shaped charges in a plurality of orientations about the perforating gun;
detonating a plurality of shaped charges in a plurality of directions, with a plurality of fluid gaps, wherein at least two fluid gaps are different lengths; and
simultaneously perforating consistent diameter holes in the plurality of directions in the cased hole at the plurality of fluid gaps, wherein the perforations at the at least two different fluid gaps are consistent with respect to each other.

2. The method of claim 1 , wherein the perforating gun is decentralized with respect to the cased hole at the predetermined location.

3. The method of claim 1 , wherein consistent diameter holes is defined as each hole diameter having less than a 10 percent deviation from the average hole size of the plurality of the holes.

4. The method of claim 1 , wherein the shaped charge comprises a case, explosive material, and a liner further comprising an axis, a first section having a substantially conical shape, a first inner surface, a lowermost apex, and a first conical angle respective to the first inner surface, a second section having a substantially frusto-conical shape, a second inner surface, and a second conical angle respective to the second inner surface, a third section having a substantially frusto-conical shape, a third inner surface, a top surface perpendicular to the axis, and a third conical angle respective to the third inner surface, the first section, second section and third section being axially aligned about the axis, the second conical angle being larger than the first conical angle, the second conical angle being larger than the third conical angle and the liner having a total height measured from the lowermost apex of the first section along the axis to a plane perpendicular to the top surface.

5. The apparatus of claim 4 , wherein the first conical angle is between 44 and 52 degrees.

6. The method of claim 4 , wherein the second conical angle is between 56 and 58 degrees.

7. The method of claim 4 , wherein the third conical angle is between 44 and 54 degrees.

8. The method of claim 4 , having a first angle break where the first section and second section intersect and having a second angle break where the second section and the third section intersect.

9. The method of claim 4 , having a first height measured along the axis from the lowermost apex to a plane perpendicular to the first angle break and having a second height measured along the axis from the lowermost apex to a plane perpendicular to the second angle break.

10. The method of claim 9 , wherein the first height is between 26 and 34 percent of the total height.

11. The method of claim 10 , wherein the second height is between 70 and 73 percent of the total height subject to the total values of first height plus the second height is 100 percent.

12. A method for perforating a formation comprising:
placing a perforating gun downhole at a predetermined location of a cased hole having an inner surface, placing a plurality of shaped charges in a plurality of orientations about the perforating gun, wherein the perforating gun is decentralized with respect to the cased hole at the predetermined location, thereby creating a plurality of fluid gaps between each perforating charge and the cased hole with at least two fluid gaps having different lengths;
detonating a plurality of shaped charges; and
perforating consistent diameter holes in the plurality of directions in the cased hole the plurality of fluid gaps, wherein the perforations at the at least two different fluid gaps are consistent with respect to each other.

13. The method of claim 12 , wherein consistent diameter holes is defined as each hole diameter having less than a 10 percent deviation from the average hole size of the plurality of the holes.

14. The method of claim 12 , wherein the shaped charge comprises a case, explosive material, and a liner further comprising an axis, a first section having a substantially conical shape, a first inner surface, a lowermost apex, and a first conical angle respective to the first inner surface, a second section having a substantially frusta-conical shape, a second inner surface, and a second conical angle respective to the second inner surface, a third section having a substantially frusta-conical shape, a third inner surface, a top surface perpendicular to the axis, and a third conical angle respective to the third inner surface, the first section, second section and third section being axially aligned about the axis, the second conical angle being larger than the first conical angle, the second conical angle being larger than the third conical angle and the liner having a total height measured from the lowermost apex of the first section along the axis to a plane perpendicular to the top surface.

15. A method for perforating a formation comprising:
placing a perforating gun downhole at a predetermined location of a cased hole having an inner surface, placing a plurality of shaped charges in a plurality of orientations about the perforating gun, wherein the perforating gun is decentralized with respect to the cased hole at the predetermined location, thereby creating a plurality of fluid gaps between each perforating charge and the cased hole with at least two fluid gaps having different lengths;
detonating a plurality of shaped charges to create explosive jets, wherein each jet has a plurality of focal points as jet propagates away from each shaped charge; and
perforating similar diameter holes in the cased hole where the focal points contact the casing.

16. The method of claim 15 , wherein similar diameter holes is defined as each hole diameter having less than a 10 percent deviation from the average hole size of the plurality of the holes.

17. The method of claim 15 , wherein the explosive jet penetrates the formation behind the casing between 29 and 44 inches in depth.

18. The method of claim 15 , wherein the explosive jet penetrates the formation behind the casing between 35 and 38 inches in depth.

19. The method of claim 15 , wherein the explosive jet penetrates the formation behind the casing between 17 and 34 inches in depth.

Assignees

• Hunting Titan Inc

Inventors

• Collins William R
• Pederson Mark Allan

Classifications

• F42B1/028

  characterised by the form of the liner · CPC title

• E21B43/117 Primary

  Shaped-charge perforators (E21B43/118 takes precedence) · CPC title