Constant entrance hole perforating gun system and method
View Patent ↗A shaped charge comprising a case, a liner positioned within the case, and an explosive filled within the case. The liner is shaped with a subtended angle ranging from 100° to 120° about an apex, a radius, and an aspect ratio such that a jet formed with the explosive creates an entrance hole in a well casing. The jet creates a perforation tunnel in a hydrocarbon formation, wherein a diameter of the jet, a diameter of the entrance hole diameter, and a width and length of the perforation tunnel are substantially constant and unaffected with changes in design and environmental factors such as a thickness and composition of the well casing, position of the charge in the perforating gun, position of the perforating gun in the well casing, a water gap in the wellbore casing, and type of the hydrocarbon formation.
1. A shaped charge for use in a perforating gun, said charge comprising a case, a liner positioned within said case, and an explosive filled within said liner; said liner shape configured with a subtended angle about an apex of said liner such that a jet formed with said explosive creates an entrance hole in a well casing: said liner having an exterior surface, said exterior surface substantially straight and conically tapered to form said apex; said subtended angle of said liner ranges from 100° to 120°, said jet creates a perforation tunnel in a hydrocarbon formation; wherein a diameter of said entrance hole is substantially equal to a diameter of a second entrance hole created by a second charge.
2. The shaped charge of claim 1 wherein a thickness of said liner is substantially constant.
3. The shaped charge of claim 2 wherein said thickness of said liner ranges from 0.01 to 0.2 inches.
4. The shaped charge of claim 2 wherein a variation of said diameter of said entrance hole in said well casing is less than 7.5%.
5. The shaped charge of claim 1 wherein said radius of said liner ranges from 0.01 to 0.5 inches.
6. The shaped charge of claim 1 wherein said diameter of said entrance hole in said well casing ranges from 0.15 to 0.75 inches.
7. The shaped charge of claim 1 wherein a width of said perforation tunnel in said hydrocarbon formation ranges from 0.15 to 1 inches.
8. The shaped charge of claim 1 wherein a variation of a width of said perforation tunnel in said hydrocarbon formation ranges is less than 5%.
9. The shaped charge of claim 1 wherein a length of said perforation tunnel in said hydrocarbon formation ranges from 1 to 20 inches.
10. The shaped charge of claim 1 wherein a variation of a length of said perforation tunnel in said hydrocarbon formation is less than 20%.
11. The shaped charge of claim 1 wherein a diameter of said jet ranges from 0.15 to 0.75 inches.
12. The shaped charge of claim 1 wherein a variation of a diameter of said jet is less than 5%.
13. The shaped charge of claim 1 wherein a thickness of said well casing ranges from 0.20 to 0.75 inches.
14. The shaped charge of claim 1 wherein a diameter of said well casing ranges from 3 to 12 inches.
15. The shaped charge of claim 1 wherein a diameter of said gun ranges from 1 to 7 inches.
16. The shaped charge of claim 1 wherein said charge in said perforating gun is oriented in an upward direction.
17. The shaped charge of claim 1 wherein said charge in said perforating gun is oriented in a downward direction.
18. The shaped charge of claim 1 wherein said perforating gun in said well casing is centralized.
19. The shaped charge of claim 1 wherein said perforating gun in said well casing is decentralized.
20. The shaped charge of claim 1 wherein a thickness of a water gap in said well casing ranges from 0.15 to 2.5 inches.
21. The shaped charge of claim 1 wherein said type of said hydrocarbon formation is selected from a group consisting of: shale, carbonate, sandstone and clay.
22. The shaped charge of claim 1 wherein said charge is selected from a group consisting of: reactive, and conventional charges.
23. The shaped charge of claim 1 wherein said second charge is located in a second perforating gun.
24. The shaped charge of claim 1 wherein said second perforating gun is located in same stage as said perforating gun.
25. The shaped charge of claim 1 wherein said second perforating gun is located in a different stage as said perforating gun.
26. The shaped charge of claim 1 wherein said second charge is located in said perforating gun.
27. A shaped charge for use in a perforating gun, said charge comprising a case, a liner positioned within said case, and an explosive filled within said liner; said liner shape configured with a subtended angle about an apex of said liner and an aspect ratio such that a jet formed with said explosive creates an entrance hole in a well casing; said subtended angle of said liner ranges from 100° to 120°; said liner having an exterior surface, said exterior surface substantially conical proximate said apex; said jet creates a perforation tunnel in a hydrocarbon formation; wherein a diameter of said jet is substantially equal to a diameter of a second jet created by a second shaped charge, a diameter of said entrance hole is substantially equal to a diameter of a second entrance hole created by said second charge, and a width and length of said perforation tunnel are substantially constant equal to a width and length of a second perforation tunnel created by said second charge in said second perforating gun.
28. A shaped charge for use in a perforating gun, said charge comprising a case, a liner positioned within said case, and an explosive filled within said liner; said liner shape configured with a subtended angle about an apex of said liner-such that a jet formed with said explosive creates an entrance hole in a well casing; said liner having an exterior surface, said exterior surface substantially straight and conically tapered to form said apex; said subtended angle of said liner ranges from 100° to 120°; said jet creates a perforation tunnel in a hydrocarbon formation; wherein a width and length of said perforation tunnel are substantially equal to a width and length of a second perforation tunnel created by said second charge.