Abstract: The present invention discloses a pressured O-ring type sealing system which allows for effective seals without expensive and time consuming machining of the sealing surface. The O-ring sealing system of the present invention allows the sealing member to conform to the natural surface irregularities of the sealing surface and to compensate for any eccentricities between the plug and the inner diameter of the member being sealed.

Abstract: The present invention is an explosive device for use in a subterranean well, the downhole portion of the well being at a higher temperature than the surface, the explosive device comprising an explosive, an electrically conductive circuit capable of supplying electricity that can fire the explosive, and, a thermal switch electrically connected in the circuit, the thermal switch being switchable from open to close as the temperature of the thermal switch is changed from the temperature on the surface to the temperature in the downhole portion, the thermal switch being set such that the explosive cannot be electrically fired until the switch is at the downhole temperature.The thermal switch may operate in either of two ways. In one embodiment, the thermal switch is connected in series in the electrical circuit, and is open at the surface temperature, thereby acting as a break in the electrical continuity of the circuit and preventing electricity from reaching the explosive.

Abstract: A perforating gun and method permit a casing or liner within a well to be perforated even within a section obstructed by sand either before or after perforation. The perforating gun comprises a support for carrying a plurality of explosive charges and one or more channels for conducting a fluid through the support, which channels are spaced from where the plurality of explosive charges are carried on the support. A method of perforating a well comprises: lowering a perforating gun into the well; flowing fluid through the perforating gun before or after the perforating gun is detonated; and detonating the perforating gun.

Abstract: Improved apparatus for perforating a subterranean formation penetrated by a well bore comprised of at least one encapsulated shaped charge held in the well bore adjacent the formation by a charge carrier optionally selected from a wire carrier or a metal strip carrier. The encapsulated shaped charge includes an ignition end and a capped discharge end, the ignition end having an extension providing cavities for containing opposed portions of a pair of wires. The capped discharge end includes a threaded extension whereby the encapsulated shaped charge can optionally be threadedly attached to a complementary threaded opening in a metal strip carrier. A wire carrier adapter nut is threadedly attached to the capped discharge end extension which provides cavities for containing opposed portions of a pair of additional wires of a four-wire carrier.

Abstract: A cartridge loaded stud gun and a complementary anode attachment fitting provide a system for explosively attaching a sacrificial anode to a subsea structure. The system is capable of being operated by a remote-controlled vehicle, and contains a means for orienting the gun and sensing its alignment in order to prevent firing the gun with the barrel canted relative to the subsea structure, a position which might permit ricocheting of the fired stud.