Abstract: A cartridge (24) for explosively operated industrial tools is disclosed. The tool (10) is of the type that has a piercer pin (46) that pierces through a surface of the cartridge during assembly of the cartridge within the tool. Then, upon firing of the cartridge, the residual gases (72) formed by the explosion are vented to the atmosphere by moving the piercer pin out of the pierced opening (70). The present cartridge includes a depression (64) in a surface of the base (62) that is in alignment with the piercer pin. There is a relatively thin section (66) of the base left at the bottom of the depression. The thin section is sized so that when it is unsupported, as for example when a defective piercer pin is used, it will fracture under the forces of the exploding powder (38) and the residual gases formed by the explosion will be vented through the fracture and into the atmosphere.

Abstract: An improved cartridge 24 is disclosed for use in an explosively operated industrial tool 10. The cartridge 24 includes a retaining plate 60 for assuring that, after firing the cartridge 24, the spent primer 32 cannot be inadvertently ejected into the interior of the tool 10, where it can subsequently adversely affect the performance of the tool 10. The retaining plate 60 is washer shaped having an upwardly turned beveled peripheral edge 64 that interferingly engages portions of a gas check member 36 that holds the primer 32. The retaining plate 60 has a hole 61 that allows access to the detonator cap 68 for firing yet will not permit passage therethrough of the detonator cap 68 itself.

Abstract: An electrical wire connector has a bifurcated bolt having opposed prongs coextending spaced from each other defining a wire-receiving channel therebetween. A nut is threaded onto the bolt until an insert carried by the nut is pressed tightly against one of the two wires disposed along the channel, to clamp the wires tightly against the bottom of the channel and electrically interconnect the wires. The nut has an internally threaded lower section within which a body section of the insert is disposed, and an upper section joined to the lower section at a frangible section adapted to break upon sufficient torque being applied to the nut by a tool, thus providing a torque limit and a visual indication of full assured interconnection.