Abstract: A perforating gun system includes shaped charges and a carrier housing containing the shaped charges and having a pattern of scallops (or other forms of perforating jet passageways). The shaped charges have one of a plurality of arrangements with respect to the scallops to provide one of a plurality of different phasing patterns and/or shot densities. The pattern of scallops includes a first set that provides a first phasing pattern and a second set that provides a second phasing pattern.

Abstract: A perforating gun apparatus comprises a plurality of perforating gun, each gun containing at least one charge and a novel arming, testing and firing apparatus. The arming, testing and firing apparatus arms a first charge in a lowermost perforating gun; however, the arming of the first charge in the lowermost perforating gun allows a tester disposed at the well surface to determine the identity of the lowermost perforating gun to be detonated. Furthermore, the arming of the first charge in the lowermost perforating gun also enables the arming of a second charge in an adjacent perforating gun of the gun string. In the event the first charge is not armed as expected, the arming, testing and firing apparatus in the lowermost perforating gun bypasses the lowermost perforating gun and begins to arm the second charge in the adjacent perforating gun of the gun string.

Abstract: A safe-arm or quick arm system for a perforating gun includes a body containing a detonator and an adapter head containing an electrical plug and a detonating cord shell, the body and associated detonator being rotatable relative to the adapter head and associated detonating cord shell. Upon rotation of the body relative to the adapter head, the detonator moves from a start position to a transport position. In this position, the plug is not electrically connected to the detonator and the leads connected to the detonator are short circuited. The detonator is not adapted to receive electrical power. Upon further rotation of the body relative to the adapter head, the detonator moves from the transport position to an electrical contact position. In this position, the plug is electrically connected to the detonator but the detonator is not aligned with the detonating cord shell.

Abstract: An improved apparatus for releasing a perforation gun from a tubing string in a well casing is disclosed. The explosion of a detonator that fires the perforation gun opens a previously sealed passageway through a wall of the apparatus of the invention. The passageway transmits bottom hole well pressure to a piston that actuates means for releasing the perforation gun. A secondary release sleeve is also provided to mechanically release the perforation gun when the piston fails to function properly. In an alternate embodiment of the apparatus of the invention, the perforation gun is released when the explosion of the detonator breaks a frangible rod that previously held one or more retaining balls within a recess in a wall of the perforation gun assembly.