Abstract: A monobore completion system where the well is completed using a tubing conveyed perforating completion system having an automatic gun release and support for the tubing conveyed perforating guns.

Abstract: A method and apparatus for perforating a subsurface formation in a pumped well. An assembly is provided which facilitates both the support of a pump in a tool string and the convection of fluid, and pressures, around the pump in the tool string. A firing head associated with the perforating gun is actuated by a pressure of differential between the tubing string bore and the wellbore annulus. This pressure differential is achieved by a downhole pump which pumps fluid out of the wellbore into the tubing string bore.

Abstract: A firing head which is actuatable by either mechanical or hydraulic force. The firing head includes two pistons, one releasable through mechanical force, and the other releasable through hydraulic force. The first piston is secured in position until application of either an impact or an upward tension on an actuation piston. The second firing piston is responsive to hydrostatic pressure.

Abstract: The present invention presents a method and apparatus for perforating a well in response to fluid pressure in a first tubing string while establishing a pressure balance in response to pressure in a second string, or in the well casing, through which the well will be produced. Additionally, redundant firing heads may be provided for perforating guns utilized to assure optimal reliability of the system. One or more perforating equipment assemblies may be employed in a tool string, each of which includes redundant firing mechanisms responsive to pressure in the tool string. Additionally, a firing head assembly is utilized which is initially responsive to pressure in the tool string, but which is subsequently actuated by annulus pressure. The firing head is suitable for use with much lower annulus pressures than are utilized with conventional hydraulically actuated firing head assemblies.

Abstract: A method and apparatus for perforating oil well casing in a well bore, with particular advantage in highly deviated well bores. The perforating guns are run into the well bore using the production tubing. A sliding sleeve is connected in the tubing above the guns and a packer is run in for setting above the sliding sleeve and guns. The assembly is run into the well bore until the guns extend into the highly deviated portion of the bore where the well casing is to be perforated. The packer is set into place, isolating that portion of the well bore below the packer from that portion above the packer, and the sliding sleeve is opened using a wireline or other means. The well bore below the packer is pressurized through the tubing to ensure that the packer is properly set. The pressure is then allowed to bleed off and the sliding sleeve is closed.

Abstract: A tool for activating the firing head of a perforating gun located below a packer by applying pressure to the upper well annulus while maintaining an unimpeded bore between the perforating gun and the pipe string. The tool is provided with a flow valve to prevent flow through the flow bore when closed, and a circulation valve which permits fluid flow from the upper annulus into the flow bore when open and a means of switching the valves so that when one is open the other is closed. A method of using the tool to complete a well is also disclosed.

Abstract: A detonator bar has an outer housing, an inner housing connected to the outer housing by at least one first frangible member, an explosive charge disposed in the inner housing, and a firing piston with firing pin held in the inner housing by at least one retaining dog and at least one second frangible member. Operation occurs in response to a relatively small impact force between the detonator bar and a perforator or other explosive object located in a subterranean well. This relatively small impact breaks the at least one first frangible member.

Abstract: An apparatus and method of operation for the release of concentric tubing strings used in well operations. In the preferred embodiment, the apparatus includes a tubing release assembly and an air chamber assembly as an actuating tool. The tubing release assembly comprises a housing, release sleeve, adjustment nut, pull tube mandrel, pull tube adapter, pull tube latch and retainer ring. The air chamber assembly as an actuating tool comprises a lower end plug, a housing, a housing retainer, seal element assembly, upper and lower shear pin retainers, upper element cone, release ring, setting mandrel, upper end plug, retrieving mandrel, and match drill assembly. Alternately, the tubing release assembly may be actuated by a ball and increased fluid pressure level within the interior of the tubing release assembly.

Abstract: Method and apparatus by which a gun firing head is maintained free of debris. An upper tubing string runs downhole in a cased borehole to a packer device. A jet gun, having a firing head located at the upper end thereof, is connected to a lower tubing string. A vent assembly is connected in series relationship within the lower string, and underlies the packer device. A barrier is contained within the lower tubing in underlying relationship to the vent and isolates the tubing interior immediately above the gun from contact with well fluids. A gun firing device is run from the surface, downhole through the packer device, and penetrates the barrier to gain access to the gun firing head, whereupon the gun is detonated, thereby perforating the casing and penetrating the payzone.

Abstract: A system for perforating a well with an annulus pressure firer is provided by the present invention. A pressure responsive means is positioned in a tubing string uphole a packer and includes a piston movable in response to a pressure differential between the upper annulus pressure and the pressure inside the tubing string. The movement of the piston is transferred through a second, concentric tubing string to a firing head on a perforating gun below the packer. The system includes a means for simultaneously decoupling the concentric tubing strings below the packer to drop the perforating gun to the bottom of the well.

Abstract: Methods and apparatus are provided for setting a packer and for placing a seal assembly into the packer bore on a single trip into the borehole. Such apparatus includes a releasable mechanism coupling the seal assembly in fixed relation to the packer until such time as the packer is at least partially set. Methods and apparatus of the present invention also include a mechanism for hydraulically setting a packer without any manipulation of the tubing string. A pair of hydraulic pistons are utilized to move in opposite directions and exert forces on both a packer actuating sleeve and the packer body to set the packer. Methods and apparatus are provided for actuating well tools in response to the hydrostatic pressure in the well. Through use of such apparatus, a chamber at atmospheric pressure is placed in communication with one side of a hydraulically movable member, the other side of which is exposed to hydrostatic pressure.

Abstract: The method and apparatus for actuating a perforating gun by pressure includes a pressure actuated gun firing head disposed on the perforating gun for detonating the shaped charges of the gun. The gun is attached to a pipe string and located downhole adjacent the formation to be perforated. The pressure actuated firing head includes a housing with a plug and piston. The piston has a firing pin adapted for engagement with the initiator of a perforating gun upon reciprocation within the housing. Initially, the piston is pressure balanced until the time of actuation. The plug is responsive to fluid pressure of a predetermined magnitude at the time of the actuation of the gun firing head. Upon effecting pressure on the plug, the plug unbalances the piston causing the piston to reciprocate. Upon reciprocation of the piston, the firing pin engages the initiator to detonate the shaped charges of the perforating gun. Pressure may be effected on the firing head through the pipe string, or the annulus, or both.

Abstract: Systems and methods for surging fluid downhole in an earth borehole, as well as tools especially adapted for use in such systems and methods, are disclosed. In a system for surging fluids, upper and lower valves both operated through the use of annulus pressure define the upper and lower extremities of a surge chamber. In a multiple surge system, first and second surge chambers are provided and a further valve is operative to surge fluids from the first surge chamber into the second surge chamber. A valve is disclosed having a longitudinal passageway initially closed by a breakable closure member. The valve is opened by breaking the closure member, and removing the broken closure member from the longitudinal passageway. The valve is operated by pressure differential between annulus pressure and atmospheric pressure which serves to accelerate a massive cutter member into the closure member for opening it. Also, a fluid pressure actuated apparatus especially useful in operating the upper valve is disclosed.

Abstract: A system for perforating a well with an annulus pressure firer is provided by the present invention. A pressure responsive means is positioned in a tubing string uphole a packer and includes a piston movable in response to a pressure differential between the upper annulus pressure and the pressure inside the tubing string. The movement of the piston is transferred through a second, concentric tubing string to a firing head on a perforating gun below the packer. The system includes a means for simultaneously decoupling the concentric tubing strings below the packer to drop the perforating gun to the bottom of the well.

Abstract: An apparatus for actuating a tool downhole in a borehole. The apparatus includes a body; a port to admit fluid pressure into the body; and apparatus within the body in fluid pressure communication with the port for actuating the tool in response to (1) a fluid pressure level communicated through the port in excess of a first fluid pressure level greater than the hydrostatic pressure level, followed by (2) a decrease in the fluid pressure level communicated through the port from the first fluid pressure level to a second fluid pressure level less than the first fluid pressure level.

Abstract: The present invention includes a gravity oriented perforating gun for use downhole in a slanted borehole. The center of gravity of the gun is located relative to the charge carrier and to a journal means to cause the charge carrier to rotate by gravity about the longitudinal axis of the gun into a predetermined relative position. A plurality of the spaced journal means support the charge carrier in low friction relationship relative to the wellbore. The individual shaped charges gravitate into a position which orients the direction of penetration to occur in a downward direction. Accordingly, production must occur in an upwardly direction through the perforations and into the slanted borehole, thereby reducing flow of formation particles into the borehole.

Abstract: Method and apparatus by which a gun firing head is maintained free of debris. An upper tubing string runs downhole in a cased borehole to a packer device. A jet gun, having a firing head located at the upper end thereof, is connected to a lower tubing string. A vent assembly is connected in series relationship within the lower string, and underlies the packer device. A barrier is contained within the lower tubing in underlying relationship to the vent and isolates the tubing interior immediately above the gun from contact with well fluids. A gun firing device is run from the surface, downhole through the packer device, and penetrates the barrier to gain access to the gun firing head, whereupon the gun is detonated, thereby perforating the casing and penetrating the payzone.

Abstract: Method and apparatus for perforating a cased borehole in a single trip into the well include two or more strings of perforating guns supported within the wellbore. The strings of guns are attached to the lower end of a pipe string and located downhole with one of the strings of guns adjacent a formation to be perforated. The first string of guns is then detonated by hydraulic actuation to perforate the formation. The pipe string is then adjusted to properly align the second string of guns either with the same formation or with another formation in the wellbore. The second string of guns may then be actuated by any known method such as impact or pressure actuation. This method and apparatus allows the same formation to be perforated twice thereby doubling the number of perforations in the cased borehole or permits the testing or completion of another formation in the same well.

Abstract: A device for actuating an explosive charge downhole in a wellbore. The device includes a combustive reaction initiator actuated in response to a first pressure condition in a portion of the wellbore and an explosive charge actuator. A time delay device is provided wherein a combustive reaction is initiated by the initiator and continues for a time delay period providing sufficient time for an operator to alter the first pressure condition to a second pressure condition desired at the time of explosive actuation. The delay device is operative at the end of the time delay period after initiation to actuate the explosive charge.

Abstract: A releasable coupling has opposite ends adpated to be connected into a tool string or tubing string and run downhole into a borehole. A sealing member is passed down through the tubing string and allowed to become seated within the axial passageway of the releasable coupling. Pressure is applied through the axial passageway above the sealing member whereupon the differential in pressure effected across the sealing member is also effected across a slidable piston reciprocatingly received within the releasable coupling. The piston moves into a position which enables a male member to be released and separated from a female member. When the male and female members are released and separated from one another, the lower part of the tubing string is disconnected from the upper part of the tubing string.