Perforating gun
In general, in one aspect, embodiments relate to a perforating gun that includes a gun body, a bulkhead assembly for coupling the perforating gun to an uphole perforating gun, where the bulkhead assembly is at least partially disposed in the gun body, and where the bulkhead assembly includes a bulkhead and electrical feedthrough formed in the bulkhead, and a charge tube assembly attached to the bulkhead assembly, where the charge tube is disposed in the gun body, and where the charge tube assembly includes a charge tube, a detonator housing interlocked with the charge tube, an end alignment interlocked with the charge tube, and a detonation cord extending from the detonator housing to the charge tube.
1. A perforating gun comprising:
a gun body;
a bulkhead assembly for coupling the perforating gun to an uphole perforating gun, wherein the bulkhead assembly is at least partially disposed in the gun body, and wherein the bulkhead assembly comprises a bulkhead and an electrical feedthrough formed in the bulkhead;
a charge tube assembly attached to the bulkhead assembly, wherein the charge tube assembly is disposed in the gun body, and wherein the charge tube assembly comprises a charge tube, a detonator housing interlocked with the charge tube, an end alignment interlocked with the charge tube, and a detonation cord extending from the detonator housing to the charge tube; and
an electrical contact comprising a contact plate, a support plate, and three or more bends disposed between the contact plate and the support plate to counteract a force applied to the contact plate when engaged by a contact pin, wherein the electrical contact is configured to convey a detonating signal through the electrical feedthrough extending through the bulkhead assembly, wherein each one of the three or more bends does not extend past a diameter of the support plate to keep the contact plate axially located during deformation from contact with the contact pin.
2. The perforating gun of claim 1 , wherein the end alignment has a mating notch configured to slide into a corresponding slot on the gun body.
3. The perforating gun of claim 2 , wherein the end alignment and the detonator housing are made of plastic.
4. The perforating gun of claim 3 , wherein the detonator housing comprises a detonating cord stop that limits insertion of the detonation cord into the detonator housing.
5. The perforating gun of claim 1 , wherein the end alignment comprises a lug and a collet that interlock with one or more openings on the charge tube.
6. The perforating gun of claim 5 , wherein the detonator housing is coupled to the charge tube by a collet and a lug snapped into place.
7. A perforating gun assembly comprising:
a first perforating gun comprising
a gun body;
a bulkhead assembly for coupling the first perforating gun to a second perforating gun, wherein the bulkhead assembly is at least partially disposed in the gun body, and wherein the bulkhead assembly comprises a bulkhead and an electrical feedthrough formed in the bulkhead; wherein the electrical feedthrough is configured to house one or more electrical connections in the perforating gun assembly;
an end alignment attached to the bulkhead assembly, wherein the end alignment engages the gun body;
an electrical contact that passes through one or more internal regions of the end alignment, wherein the electrical contact comprises a contact plate, a support plate, and three or more bends disposed between the contact plate and the support plate to counteract a force applied to the contact plate when engaged by a contact pin, wherein each one of the three or more bends does not extend past a diameter of the support plate to keep the contact plate axially located during deformation from contact with the contact pin;
a charge tube interlocked with the end alignment, wherein the charge tube holds
a plurality of perforating charges disposed in corresponding charge cases; and
a detonator housing interlocked with the charge tube; and
the second perforating gun comprising:
a gun body;
a bulkhead assembly for coupling the first perforating gun to a third perforating gun, wherein the bulkhead assembly is at least partially disposed in the gun body, and wherein the bulkhead assembly comprises a bulkhead and electrical feedthrough formed in the bulkhead that is configured to house one or more electrical connections in the perforating gun assembly; an end alignment attached to the bulkhead assembly, wherein the end alignment engages the gun body;
a charge tube interlocked with the end alignment, wherein the charge tube holds a plurality of perforating charges disposed in corresponding charge cases; and
a detonator housing interlocked with the charge tube, wherein the detonator housing of the second perforating gun is secured in the bulkhead assembly of the first perforating gun.
8. The perforating gun assembly of claim 7 , wherein each end alignment comprises a collet and a lug that interlock with one or more openings of the corresponding charge tube.
9. The perforating gun assembly of claim 7 , wherein each end alignment comprises one or more protrusions that mate to one or more slots of the corresponding gun body.
10. The perforating gun assembly of claim 7 , wherein the one or more electrical connections comprise the electrical contact configured to engage or be engaged by one or more contact pins.
11. The perforating gun assembly of claim 10 , wherein the electrical contact comprises four or more flexible bends disposed between a contact plate and a support plate.
12. The perforating gun assembly of claim 11 , wherein each end alignment comprises:
at least two different portions of the corresponding electrical feedthrough configured to limit side-to-side mobility of the corresponding electrical contact through contact with one or more fins disposed about a central axis of the corresponding electrical contact; and
at least one material cut-out section for reducing a total volume of space occupied by the end alignments.
13. The perforating gun assembly of claim 7 , each perforating gun comprising a grounding clip for grounding the detonator housing to the corresponding charge tube, bulkhead, and/or gun body.
14. The perforating gun assembly of claim 7 , each detonator housing comprising:
a detonating cord receptacle having a detonating cord stop; and
a detonator receptacle having a detonator stop.
15. A method comprising:
disposing a perforating gun assembly in a wellbore extending into a subterranean formation, wherein the perforating gun assembly comprises at least one perforating gun comprising:
a gun body;
a bulkhead assembly for coupling the at least one perforating gun to an uphole perforating gun of the perforating gun assembly, wherein the bulkhead assembly is disposed in the gun body, and wherein the bulkhead assembly comprises a bulkhead and electrical feedthrough formed in the bulkhead; that is configured to house one or more electrical connections in the perforating gun assembly;
an end alignment attached to the bulkhead assembly, wherein the end alignment engages the gun body;
an electrical contact that passes through one or more internal regions of the end alignment, wherein the electrical contact comprises a contact plate, a support plate, and three or more bends disposed between the contact plate and the support plate to counteract a force applied to the contact plate when engaged by a contact pin, wherein each one of the three or more bends does not extend past a diameter of the support plate to keep the contact plate axially located during deformation from contact with the contact pin;
a charge tube interlocked with the end alignment, wherein the charge tube holds a plurality of perforating charges disposed in corresponding charge cases; and
a detonator housing interlocked with the charge tube.
16. The method of claim 15 , wherein the end alignment comprises a collet and a lug that interlock with one or more openings on the charge tube.
17. The method of claim 15 , wherein the detonator housing is coupled to the charge tube by one or more snap fit fasteners.
18. The method of claim 15 , wherein the end alignment comprises three or more radial protrusions circumferentially spaced about a central axis of the end alignment.
19. The method of claim 15 , wherein each end alignment comprises one or more cut-out sections for reducing a total volume of space occupied by the one or more end alignments.
20. The method of claim 15 , further comprising:
limiting side-to-side mobility of the electrical connection within the end alignment of the at least one perforating gun by contacting one or more fins disposed about a support plate of the electrical contact with the electrical feedthrough.