Pressure activated selective perforating switch support
A method, system, and apparatus for restraining a firing pin using a bushing for use in a downhole switch that is armed using the explosive energy of a previously detonated shaped charge.
1. A switch for use downhole comprising:
an outer cylindrical housing having a common axis and a thru bore;
an inner cylindrical housing located within the thru bore of the outer cylindrical housing having an outer surface and a thru bore where the outer surface is electrically insulated from the thru bore;
a cylindrical electrically conductive receptacle having a thru bore and located within the thru bore of the inner cylindrical housing;
an electrically conductive piston with a first end having a conical cavity, a distal end, and a radial groove about the distal end;
an electrically insulating piston sleeve surrounding the circumference of the first end of the piston;
an electrically conductive firing pin having a first cylindrical segment, a second cylindrical segment, and a third cylindrical segment, wherein the first cylindrical segment is slideably engaged with the inner thru bore of the receptacle, the second cylindrical segment is slideably engaged with the thru bore of the inner cylindrical housing, the third cylindrical segment having a conical distal end located adjacent to the conical bore of the piston;
an electrically insulating bushing with a base end, a cylindrical sleeve, a distal end, and an inner bore, wherein the inner bore is slideably engaged with the distal end of the piston;
a retainer ring in the circumferential groove of the distal end of the piston;
wherein the circumferential groove of the distal end of the piston extends beyond the distal end of the bushing; and
wherein the base end of the bushing is proximate to the piston sleeve.
2. A switch for use downhole comprising:
an outer cylindrical housing having a common axis and a thru bore;
an inner cylindrical housing located within the thru bore of the outer cylindrical housing having an outer surface and a thru bore where the outer surface is electrically insulated from the thru bore;
a cylindrical electrically conductive receptacle having a thru bore and located within the thru bore of the inner cylindrical housing;
an electrically conductive piston with a first end having a conical cavity, a distal end, and a radial groove about the distal end;
an electrically insulating piston sleeve surrounding the circumference of the first end of the piston;
an electrically conductive firing pin having a first cylindrical segment, a second cylindrical segment, and a third cylindrical segment, wherein the first cylindrical segment is slideably engaged with the inner thru bore of the receptacle, the second cylindrical segment is slideably engaged with the thru bore of the inner cylindrical housing, the third cylindrical segment having a conical distal end located adjacent to the conical bore of the piston;
an electrically insulating bushing with a base end, a cylindrical sleeve, a distal end, and an inner bore, wherein the inner bore is slideably engaged with the distal end of the piston;
a shear pin in the circumferential groove of the distal end of the piston;
wherein the circumferential groove of the distal end of the piston extends beyond the distal end of the bushing; and
wherein the base end of the bushing is proximate to the piston sleeve.
3. A switch for use downhole comprising:
an outer cylindrical housing having a common axis and a thru bore;
an inner cylindrical housing located within the thru bore of the outer cylindrical housing having an outer surface and a thru bore where the outer surface is electrically insulated from the thru bore;
a cylindrical electrically conductive receptacle having a thru bore and located within the thru bore of the inner cylindrical housing;
an electrically conductive piston with a first end having a conical cavity, a distal end, and a radial groove about the distal end;
an electrically insulating piston sleeve surrounding the circumference of the first end of the piston;
an electrically conductive firing pin having a first cylindrical segment, a second cylindrical segment, and a third cylindrical segment, wherein the first cylindrical segment is slideably engaged with the inner thru bore of the receptacle, the second cylindrical segment is slideably engaged with the thru bore of the inner cylindrical housing, the third cylindrical segment having a conical distal end located adjacent to the conical bore of the piston;
an electrically insulating bushing with a base end, a cylindrical sleeve, a distal end, and an inner bore, wherein the inner bore is slideably engaged with the distal end of the piston;
a retainer end cap with an inner frusto conical surface ending in a thru bore wherein the thru bore is slideably engaged with the cylindrical wall of the bushing;
wherein the circumferential groove of the distal end of the piston extends beyond the distal end of the bushing; and
wherein the base end of the bushing is proximate to the piston sleeve.
4. A switch for use downhole comprising:
an outer cylindrical housing having a common axis and a thru bore;
an inner cylindrical housing located within the thru bore of the outer cylindrical housing having an outer surface and a thru bore where the outer surface is electrically insulated from the thru bore;
a cylindrical electrically conductive receptacle having a thru bore and located within the thru bore of the inner cylindrical housing;
an electrically conductive piston with a first end having a conical cavity, a distal end, and a radial groove about the distal end;
an electrically insulating piston sleeve surrounding the circumference of the first end of the piston;
an electrically conductive firing pin having a first cylindrical segment, a second cylindrical segment, and a third cylindrical segment, wherein the first cylindrical segment is slideably engaged with the inner thru bore of the receptacle, the second cylindrical segment is slideably engaged with the thru bore of the inner cylindrical housing, the third cylindrical segment having a conical distal end located adjacent to the conical bore of the piston;
an electrically insulating bushing with a base end, a cylindrical sleeve, a distal end, and an inner bore, wherein the inner bore is slideably engaged with the distal end of the piston; and
a cylindrical end cap retainer having a frusto-conical thru bore with an inner shoulder, a countersink end, wherein the inner shoulder is slideably engaged with the cylindrical sleeve of the support bushing and the countersink end fits flush over the support bushing cylindrical sleeve and also fits flush against the second face of the cylindrical housing;
wherein the circumferential groove of the distal end of the piston extends beyond the distal end of the bushing; and
wherein the base end of the bushing is proximate to the piston sleeve.
5. A system for use downhole comprising:
at least one perforating gun with a first end and a second end, the first end being coupled to a first tandem sub;
at least one shaped charge installed within a charge tube located within the at least one perforating gun;
a detonating cord coupled to the at least one shaped charge;
a detonator coupled to the detonating cord and installed in the tandem sub;
an arming switch electrically coupled to the detonator, the arming switch further comprising:
an electrically conductive outer cylindrical housing having a common axis and a thru bore;
an electrically insulating inner cylindrical housing located within the thru bore of the outer cylindrical housing and having a thru bore;
an electrically conductive cylindrical receptacle having a thru bore and located within the thru bore of the inner cylindrical housing;
an electrically conductive piston with a first end having a conical bore and a distal end having a proximately located circumferential groove;
an electrically conductive firing pin having a first cylindrical segment, a second cylindrical segment, and a third cylindrical segment, wherein the first cylindrical segment is slideably engaged with the inner thru bore of the receptacle, the second cylindrical segment is slideably engaged with the thru bore of the inner cylindrical housing, the third cylindrical segment having a conical distal end located adjacent to the conical bore of the piston;
a bushing with a disc base end, a cylindrical wall, a distal end, and an inner bore, wherein the inner bore is slideably engaged with the distal end of the piston; and
a retainer ring in the circumferential groove of the distal end of the piston.
6. A system for use downhole comprising:
at least one perforating gun with a first end and a second end, the first end being coupled to a first tandem sub;
at least one shaped charge installed within a charge tube located within the at least one perforating gun;
a detonating cord coupled to the at least one shaped charge;
a detonator coupled to the detonating cord and installed in the tandem sub;
an arming switch electrically coupled to the detonator, the arming switch further comprising:
an electrically conductive outer cylindrical housing having a common axis and a thru bore;
an electrically insulating inner cylindrical housing located within the thru bore of the outer cylindrical housing and having a thru bore;
an electrically conductive cylindrical receptacle having a thru bore and located within the thru bore of the inner cylindrical housing;
an electrically conductive piston with a first end having a conical bore and a distal end having a proximately located circumferential groove;
an electrically conductive firing pin having a first cylindrical segment, a second cylindrical segment, and a third cylindrical segment, wherein the first cylindrical segment is slideably engaged with the inner thru bore of the receptacle, the second cylindrical segment is slideably engaged with the thru bore of the inner cylindrical housing, the third cylindrical segment having a conical distal end located adjacent to the conical bore of the piston;
a bushing with a disc base end, a cylindrical wall, a distal end, and an inner bore, wherein the inner bore is slideably engaged with the distal end of the piston; and
a shear pin in the circumferential groove of the distal end of the piston.
7. A system for use downhole comprising:
at least one perforating gun with a first end and a second end, the first end being coupled to a first tandem sub;
at least one shaped charge installed within a charge tube located within the at least one perforating gun;
a detonating cord coupled to the at least one shaped charge;
a detonator coupled to the detonating cord and installed in the tandem sub;
an arming switch electrically coupled to the detonator, the arming switch further comprising:
an electrically conductive outer cylindrical housing having a common axis and a thru bore;
an electrically insulating inner cylindrical housing located within the thru bore of the outer cylindrical housing and having a thru bore;
an electrically conductive cylindrical receptacle having a thru bore and located within the thru bore of the inner cylindrical housing;
an electrically conductive piston with a first end having a conical bore and a distal end having a proximately located circumferential groove;
an electrically conductive firing pin having a first cylindrical segment, a second cylindrical segment, and a third cylindrical segment, wherein the first cylindrical segment is slideably engaged with the inner thru bore of the receptacle, the second cylindrical segment is slideably engaged with the thru bore of the inner cylindrical housing, the third cylindrical segment having a conical distal end located adjacent to the conical bore of the piston;
a bushing with a disc base end, a cylindrical wall, a distal end, and an inner bore, wherein the inner bore is slideably engaged with the distal end of the piston; and
a retainer end cap with an inner frusto conical surface ending in a thru bore wherein the thru bore is slideably engaged with the cylindrical wall of the bushing.
8. The apparatus of claim 1 wherein the bushing base end is proximate to the outer housing.
9. The apparatus of claim 1 wherein the distal end of the bushing is proximate to the circumferential groove of the distal end of the piston.
10. The apparatus of claim 1 further comprising an o-ring in the circumferential groove of the distal end of the piston.
11. The apparatus of claim 1 wherein the first cylindrical segment of the firing pin is covered in an electrical insulator.
12. The apparatus of claim 1 wherein the first cylindrical segment of the firing pin is covered in an electrically non-conductive material.
13. The apparatus of claim 1 further comprising a first wire electrically coupled to the first cylindrical segment of the firing pin.
14. The apparatus of claim 1 further comprising a second wire electrically coupled to the outer cylindrical housing.
15. The apparatus of claim 1 further comprising diode in series with the second wire.
16. The apparatus of claim 1 wherein the shoulder of the base end of the bushing is disposed between the trainer and the outer housing.
17. The apparatus of claim 2 wherein the bushing base end is proximate to the outer housing.
18. The apparatus of claim 2 wherein the distal end of the bushing is proximate to the circumferential groove of the distal end of the piston.
19. The apparatus of claim 2 further comprising an o-ring in the circumferential groove of the distal end of the piston.
20. The apparatus of claim 2 wherein the first cylindrical segment of the firing pin is covered in an electrical insulator.
21. The apparatus of claim 2 wherein the first cylindrical segment of the firing pin is covered in an electrically non-conductive material.
22. The apparatus of claim 2 further comprising a first wire electrically coupled to the first cylindrical segment of the firing pin.
23. The apparatus of claim 2 further comprising a second wire electrically coupled to the outer cylindrical housing.
24. The apparatus of claim 2 further comprising diode in series with the second wire.
25. The apparatus of claim 2 wherein the shoulder of the base end of the bushing is disposed between the trainer and the outer housing.
26. The apparatus of claim 3 wherein the bushing base end is proximate to the outer housing.
27. The apparatus of claim 3 wherein the distal end of the bushing is proximate to the circumferential groove of the distal end of the piston.
28. The apparatus of claim 3 further comprising an o-ring in the circumferential groove of the distal end of the piston.
29. The apparatus of claim 3 wherein the first cylindrical segment of the firing pin is covered in an electrical insulator.
30. The apparatus of claim 3 wherein the first cylindrical segment of the firing pin is covered in an electrically non-conductive material.
31. The apparatus of claim 3 further comprising a first wire electrically coupled to the first cylindrical segment of the firing pin.
32. The apparatus of claim 3 further comprising a second wire electrically coupled to the outer cylindrical housing.
33. The apparatus of claim 3 further comprising diode in series with the second wire.
34. The apparatus of claim 3 wherein the shoulder of the base end of the bushing is disposed between the trainer and the outer housing.
35. The apparatus of claim 4 wherein the bushing base end is proximate to the outer housing.
36. The apparatus of claim 4 wherein the distal end of the bushing is proximate to the circumferential groove of the distal end of the piston.
37. The apparatus of claim 4 further comprising an o-ring in the circumferential groove of the distal end of the piston.
38. The apparatus of claim 4 wherein the first cylindrical segment of the firing pin is covered in an electrical insulator.
39. The apparatus of claim 4 wherein the first cylindrical segment of the firing pin is covered in an electrically non-conductive material.
40. The apparatus of claim 4 further comprising a first wire electrically coupled to the first cylindrical segment of the firing pin.
41. The apparatus of claim 4 further comprising a second wire electrically coupled to the outer cylindrical housing.
42. The apparatus of claim 4 further comprising diode in series with the second wire.
43. The apparatus of claim 4 wherein the shoulder of the base end of the bushing is disposed between the trainer and the outer housing.
44. The apparatus of claim 5 wherein the distal end of the bushing is aligned with the circumferential groove of the distal end of the piston.
45. The apparatus of claim 5 further comprising an o-ring in the circumferential groove of the distal end of the piston.
46. The apparatus of claim 5 wherein the first cylindrical segment of the firing pin is covered in an electrical insulator.
47. The apparatus of claim 5 wherein the first cylindrical segment of the firing pin is covered in an electrically non-conductive material.
48. The apparatus of claim 5 wherein the second cylindrical segment of the firing pin is electrically conductive.
49. The apparatus of claim 5 wherein the receptacle is electrically conductive.
50. The apparatus of claim 5 further comprising a first wire electrically coupled to the first cylindrical segment of the firing pin.
51. The apparatus of claim 5 further comprising a second wire electrically coupled to the receptacle.
52. The apparatus of claim 5 further comprising diode in series with the second wire.
53. The system of claim 5 further comprising the second end being coupled to a second tandem sub.
54. The apparatus of claim 6 wherein the distal end of the bushing is aligned with the circumferential groove of the distal end of the piston.
55. The apparatus of claim 6 further comprising an o-ring in the circumferential groove of the distal end of the piston.
56. The apparatus of claim 6 wherein the first cylindrical segment of the firing pin is covered in an electrical insulator.
57. The apparatus of claim 6 wherein the first cylindrical segment of the firing pin is covered in an electrically non-conductive material.
58. The apparatus of claim 6 wherein the second cylindrical segment of the firing pin is electrically conductive.
59. The apparatus of claim 6 wherein the receptacle is electrically conductive.
60. The apparatus of claim 6 further comprising a first wire electrically coupled to the first cylindrical segment of the firing pin.
61. The apparatus of claim 6 further comprising a second wire electrically coupled to the receptacle.
62. The apparatus of claim 6 further comprising diode in series with the second wire.
63. The system of claim 6 further comprising the second end being coupled to a second tandem sub.
64. The apparatus of claim 7 wherein the distal end of the bushing is aligned with the circumferential groove of the distal end of the piston.
65. The apparatus of claim 7 further comprising an o-ring in the circumferential groove of the distal end of the piston.
66. The apparatus of claim 7 wherein the first cylindrical segment of the firing pin is covered in an electrical insulator.
67. The apparatus of claim 7 wherein the first cylindrical segment of the firing pin is covered in an electrically non-conductive material.
68. The apparatus of claim 7 wherein the second cylindrical segment of the firing pin is electrically conductive.
69. The apparatus of claim 7 wherein the receptacle is electrically conductive.
70. The apparatus of claim 7 further comprising a first wire electrically coupled to the first cylindrical segment of the firing pin.
71. The apparatus of claim 7 further comprising a second wire electrically coupled to the receptacle.
72. The apparatus of claim 7 further comprising diode in series with the second wire.
73. The system of claim 7 further comprising the second end being coupled to a second tandem sub.