Abstract: A tubing and casing cutter is shown which can be assembled in the field from a plurality of pressed segmented pellets of free standing explosive material. The segmented pellets have a liner glued to at least one exposed face thereof. The pellets are glued to a backup plate with two mirror image plates being stacked to form a plate assembly. A plurality of plate assemblies are stacked within a surrounding container to form the cutter. The pressed pellets can also be assembled within a cup-shaped container to form a shaped charge.

Abstract: A liner for a explosive shaped charge, such as those used in perforating operations in oil and gas wells, is formed from a powdered metal mixture that includes molybdenum. The molybdenum allows a higher density liner to be formed to create denser jets for achieving deeper penetration, but without the negative effects that often accompany the use of higher density materials. The molybdenum may be used in the amount of 0.5% to 25% by weight of the metal mixture, with tungsten and other constituents forming the remainder of the mixture.

Abstract: A tubing conveyed perforating apparatus is shown which includes a tubular firing section which carries a plurality of explosive charges. The explosive charges are initially aligned with regions of reduced wall area provided in a tubular firing section which initially surrounds the charges. A piston sleeve is mounted on the exterior of the firing section. The piston sleeve has a plurality of apertures which are initially aligned with the regions of reduced wall area in the tubular firing section and thus with the explosive charges. Detonation of the charges causes the piston sleeve to shift so that the piston sleeve apertures are out of alignment with openings formed in the tubular firing section by the detonation of the charges, thereby trapping any resulting debris within the interior of the tubular firing section. Firing of the explosive charges opens upper and lower circulating ports so that sand or other debris can be reverse circulated up the interior of the well string to the well surface.

Abstract: A shaped charge is shown with enhanced creep resistance for use in a perforating gun having an elongated spiral strip open to the wellbore through which the charges are attached. The shaped charge is a hollow bodied capsule and hollow bodied cap, both threaded for easy attachment to one another. At least the capsule consists of an alloy of, by weight, between about 4 and 12 percent copper, 2 and 4 percent aluminum, and the balance zinc and impurities.

Abstract: A device for cutting a detonating cord having an explosive core is provided. The device includes a detonating cord holding member having a cord holding portion, such as an aperture or recess, configured to closely receive the detonating cord so that the detonating cord is held in place relative to the holding member. The cord holding member also has a side surface from which the detonating cord projects when the detonating cord is held in the cord holding portion prior to cutting. A blade arm is pivotally mounted to the cord holding member. The blade arm carries a sharpened blade and is pivotal between an open and closed position. The blade passes over the cord holding portion in close proximity to the side surface so that the detonating cord is cut by the blade as the blade is passed over the cord holding portion.

Abstract: A tubing conveyed perforating apparatus is shown which includes a tubular assembly made up of a plurality of tubular sections. A plurality of explosive charges are located within the interior bore of at least two of the tubular sections of the tubular assembly. A firing head is carried on the tubular assembly for detonating the explosive charges to perforate a surrounding well bore. The firing head has a concentric detonator arrangement within a hollow central bore. The explosive charges are held within the interior bore of the tubular section by a support. The explosive charges and charge support are comprised of materials which disintegrate upon detonation of the explosive charges, whereby the interior bore of the tubular assembly is fully open after detonation.

Abstract: An improved downhole explosive charge carrier is disclosed. The invention uses a unique staggered charge pattern and a mounting configuration which allows the use of a straight, axially-located detonator in order to achieve a greater number of shots per unit length over conventional carriers. The invention also reduces the interference caused by the detonator and the closeness of the shots and thereby increases the performance of the individual charges, allowing smaller charges to be used to achieve the same perforation size.

Abstract: Shaped charge liners are formed from an alloy of nickel, tin, and copper, which is first formed into a powder, and then pressed into strips. The pressed strips of powdered alloy are next sintered and then cold rolled. Thereafter, the powdered, pressed, and sintered alloy strips are formed into shaped charge liners, for example, by stamping. The shaped charge liners may be heat treated either before or after the forming step.

Abstract: A tubing conveyed perforating apparatus is shown which includes a tubular assembly made up of a plurality of tubular sections. One or more elongate charge holders are located within the interior bore of the tubular assembly and carry explosive charges thereon. A firing head is carried on the tubular assembly for detonating the explosive charges to perforate a surrounding well bore. The charge holders and explosive charges are comprised of materials which disintegrate upon detonation of the explosive charges, whereby the interior bore of the tubular assembly is fully open after detonation.

Abstract: A shaped charge and liner having a minimum outside diameter determined by the formula:D.sub.L =2.625-0.3571(6 -D.sub.ID)Where:D.sub.L =Liner Minimum Outside DiameterD.sub.ID =Carrier Inside DiameterThe geometry of the shaped charge reduces the chances of interference between charges by controlling burn time, as does the positioning of the primer cord. The liner has an open end with a minimum outside diameter determined by the formula. The shape of the case and liner is determined by keeping the center of the primer cord a distance not greater than 0.10 (D.sub.ID) from the center line of the carrier, ideally not greater than 0.05 (D.sub.ID). This yields a large diameter, flat shaped charge that may be loaded in a tubular carrier having a charge or perforation density of at least 10 shots per foot.

Abstract: A high density perforating gun having a carrier housing tube and an interior charge holder tube through which are mounted zinc alloy shaped charges in a phased relationship between about 135 and 145 degrees. The 135 to 145 degree phased relationship provides for an 18 shot per foot perforating gun system. The shaped charges of selected length are inserted into the carrier housing tube and held in place by fastener rings fitted to fastener ring slots. The nose ends of the shaped charges are fitted with ears to receive a detonating cord. This positions the primer cord in tension and generally coaxially with the carrier housing tube to prevent charge interference and assure sequential detonation.

Abstract: A perforating gun having an elongated mounting strip and a selected wave or non-linear, zig-zag form as seen in a plan view, with an outer surface diameter sized for convenient insertion and removal from a well. The mounting strip has a series of openings spaced in intervals for mounting capsule explosive charges in a phased relationship between 0 and 360 degrees. The cross-sectional area of the mounting strip around each opening is selected to prevent fragmentation of the carrier upon detonation of the charges. The mounting strip is preferably metallic with a selected amplitude and wave length. In each opening is an explosive capsule with a hollow cap with a nose for attachment to one of the openings. The cap has an annular, interior thread with a thread run-out of selected width.

Abstract: A perforating gun having an elongated, spiral strip with an outer surface, cylindrical about a longitudinal axis, and a diameter sized for convenient entry and removal from a well. The strip has a series of threaded openings spaced in intervals for mounting capsule explosive charges in a phased relationship between 0 and 360 degrees. The cross-sectional area of the strip around each opening is selected to prevent fragmentation of the carrier upon detonation of the charges. The spiral strip is preferably metallic and forms a helical band with a pitch in a range of 12 to 24 inches. In each threaded opening is an explosive capsule with a hollow cap having at one end a threaded nose for attachment to one of the threaded openings. The cap has an annular, interior thread with a thread run-out of selected width at the other end.

Abstract: A longitudinally slotted carrier having one end adapted for mounting on a tubing string, the carrier being nonplanar, with a slotted configuration and interior dimensions to enable capsule charge orientation at selected phases between 0 and 360 degrees. The carrier has a frangible seam that fractures upon detonation to form two retrievable strips, each supported by the tubing string for retrieval. The seam is a narrow bridge, formed by slotting the carrier, with a cross sectional area that shatters upon detonation of the shaped charges. The remaining cross sectional area of each strip is sufficient to assure retrieval after detonation. The strips are nonplanar, arcuate or a segment of a circle in cross section. When the capsule charges are arrayed around many phases, by attaching both from and rear portions of the capsule charges to the unslotted regions of the carrier, plural primer cords are used for detonation.

Abstract: A system for safely transporting detonating cord that uses a container with a mounting board of insulating material with a walled path through which the cord is threaded. The path has a series of loop regions and adjoining, parallel regions through which the parallel cord is separated with a cord separator that will sever adjoining cord in the event of a detonation to terminate further cord detonation. A separator card of cardboard is an ideal separator means. The walled path must otherwise insulate the detonating cord, being formed in one embodiment of cylindrical cardboard tube and in another of expanded polystyrene having a path with an open top. Fastener means secures the detonating cord within the walled path, being "Nylon" in the tube embodiment and interference fit in the expanded polystyrene embodiment.