Pass-through bulkhead connection switch for a perforating gun

A system for making perforations in a well casing at multiple depth locations in a sequential or non-sequential manner, the perforations being configured to access one or more of oil and gas deposits disposed within a rock layer below ground and to channel the same into the well, the system comprising:

• a first perforating gun assembly comprising a first plurality of charges and a first detonation mechanism configured to detonate the first plurality of charges;
• and
• a second perforating gun assembly comprising a second plurality of charges, an isolation subassembly, and a second detonation mechanism located in the isolation subassembly, the second detonation mechanism being configured to detonate the second plurality of charges;
• and
• a pass-through bulkhead connection switch in electrical communication with the first detonation mechanism and with the second detonation mechanism, the pass-through bulkhead connection switch including an uninterrupted electrically conductive pin and an electrically insulating body at least partially surrounding and electrically insulating the conductive pin, the pass-through bulkhead switch being configured to communicate a detonation signal to the first detonation mechanism and to prevent or reduce increase of pressure about the second detonation mechanism from a blast wave formed after the detonation of the first plurality of charges, wherein:
• the conductive pin comprises a front portion, a back portion, a center portion, and a transition shoulder between the back portion and the center portion, at least a portion of the back portion having a first outer diameter, at least a portion of the center portion having a second outer diameter that is different from the first outer diameter;
• and
• the insulating body comprises an aperture passing therethrough, the aperture having a first internal diameter in a first portion thereof, the first internal diameter generally corresponding to the first outer diameter of the back portion, a second internal diameter in a second portion thereof, the second internal diameter generally corresponding to the second outer diameter of the center portion, and a shoulder formed between the first internal diameter and the second internal diameter, the shoulder in the aperture and the transition shoulder of the conductive pin being configured to cooperate to create a seal between the conductive pin and the insulating body and to limit axial movement of the conductive pin relative to the insulating body.

A method of reliably sequentially transmitting detonation signals to detonation mechanisms of multiple perforating gun assemblies and detonating explosive charges housed in the perforating gun assemblies, the method comprising:

• isolating a first detonation mechanism in a first isolation chamber of a first perforating gun assembly by sealing the first isolation chamber with a pass-through bulkhead connection switch that includes an uninterrupted electrically conductive pin and an electrically insulating body at least partially surrounding and electrically insulating the conductive pin, the conductive pin comprising a front portion, a back portion having a first outer diameter, a center portion having a second outer diameter, and a transition shoulder between the back portion and the center portion, the insulating body comprising an aperture passing therethrough that has a first internal diameter in a first portion thereof, a second internal diameter in a second portion thereof, and a shoulder formed between the first internal diameter and the second internal diameter, the first internal diameter generally corresponding to the first outer diameter of the back portion and the second internal diameter generally corresponding to the second outer diameter of the center portion, the shoulder in the aperture and the transition shoulder of the conductive pin being configured to cooperate to create a seal between the conductive pin and the insulating body and to limit axial movement of the conductive pin relative to the insulating body during a detonation, the first detonation mechanism being in electrical communication with the pass-through bulkhead connection switch, and the pass-through bulkhead connection switch being in electrical communication with a second detonation mechanism;
• and
• detonating a second plurality of charges located in a second perforating gun assembly by sending a detonation signal through the pass-through bulkhead connection switch to the second detonation mechanism, wherein the pass-through bulkhead connection switch is configured to at least partially block a blast wave generated by the detonation of the second plurality of charges.