Abstract: An arming tandem for a perforating gun is provided. The arming tandem includes an internal arming pin that is biased in a retracted position. Detonating the last perforating gun in a gun string forces the arming pin in the immediately adjacent tandem into contact with a grounding plate in the next perforating gun, thereby arming the next perforating gun. The arming pin is biased in the retracted position by a helical compression spring that is contained within a counterbored opening in the arming tandem. An adjacent bulkhead includes a grounding plate that surrounds a contact pin. The grounding plate provides a flat surface for contacting the arming pin and creating a secure connection to ground.

Abstract: An improved perforating gun system is provided. The perforating gun system includes a perforating gun having a shaped charge positioning tube that is securely received within a female opening in a tandem to provide a 360-degree connection to ground. The shaped charge positioning tube includes segmented end portions that extend over first and second contact housings. Each contact housing includes a contact pin that is biased outwardly by a spring, the spring comprising a portion of an electrical path for a firing signal.

Abstract: An improved perforating gun. The perforating gun includes an internal charge holder formed from a conductive material and comprising a grounding tab. The grounding tab protrudes through a first end cap and is in direct electrical contact with a tandem for grounding the internal charge holder. An optional second grounding tab protrudes through a second end cap and is in direct electrical contact with a second tandem. Each end cap includes a contact pin that engages a signal transfer pin contained within a tandem. The contact pins are biased outwardly by respective compression springs, and each compression spring comprises a portion of an electrical path for a firing signal.

Abstract: A self-positioning system for a perforating gun or gun string is provided. The self-positioning system includes a plurality of protrusions extending outwardly from the perforating gun or the gun string for providing a finite number of rotational positions and/or for providing a desired water clearance. The protrusions include one or more groupings of at least three protrusions, the protrusions being angularly offset from each other about the outer circumference of the perforating gun or gun string.

Abstract: An improved perforating gun is provided. The perforating gun includes an outer loading tube, an internal charge holder, an addressable switch housing, and a detonator housing. In some embodiments, the addressable switch housing and the detonator housing are separate components that are joined to the outer loading tube. In other embodiments, the addressable switch housing is integrally joined to a first portion of the internal charge holder and the detonator housing is integrally joined to a second portion of the internal charge holder. When detonated, a plurality of shaped charges create a plurality of perforations through a wellbore casing, the perforations being angularly offset from each other within a single perforation plane, optionally followed by a hydraulic fracturing stage.

Abstract: An improved perforating gun is provided. The perforating gun includes an internal charge holder formed from a conductive material and comprising a grounding tab. The grounding tab protrudes through a first end cap and is in direct electrical contact with a tandem for grounding the internal charge holder. An optional second grounding tab protrudes through a second end cap and is in direct electrical contact with a second tandem. Each end cap includes a contact pin that engages a signal transfer pin contained within a tandem. The contact pins are biased outwardly by respective compression springs, and each compression spring comprises a portion of an electrical path for a firing signal.

Abstract: An improved perforating gun is provided. The perforating gun includes an outer loading tube, an internal charge holder, an addressable switch housing, and a detonator housing. In some embodiments, the addressable switch housing and the detonator housing are separate components that are joined to the outer loading tube. In other embodiments, the addressable switch housing is integrally joined to a first portion of the internal charge holder and the detonator housing is integrally joined to a second portion of the internal charge holder. When detonated, a plurality of shaped charges create a plurality of perforations through a wellbore casing, the perforations being angularly offset from each other within a single perforation plane, optionally followed by a hydraulic fracturing stage.

Abstract: A self-positioning system for a perforating gun or gun string is provided. The self-positioning system includes a plurality of protrusions extending outwardly from the perforating gun or the gun string for providing a finite number of rotational positions and/or for providing a desired water clearance. The protrusions include one or more groupings of at least three protrusions, the protrusions being angularly offset from each other about the outer circumference of the perforating gun or gun string.

Abstract: An apparatus and method is provided to reduce interference resulting from activation of explosive devices. One type of interference is charge-to-charge interference, and another type of interference is pre-shock interference between a detonating cord and an explosive, such as a shaped charge. To reduce interference, one or more shock impeding elements are placed proximal one or more explosives to impede propagation of shock caused by detonation of the explosives. The shock impeding elements include a porous material, such as a porous liquid or solid. In another arrangement, a shock barrier may be positioned between a detonating cord and an explosive to reduce pre-shock interference. In yet another feature, an encapsulant may be provided around one or more shaped charges to enhance structural support for the shaped charges.