Abstract: Device for producing focused explosions, comprises a rigid outer shell, an explosive filling, the explosive filling comprising a plurality of inwardly extending hollows; and a gap defined between the explosive filling and the rigid outer shell.

Abstract: An assembly (7) for triggering an explosive in a hole (9) to produce an explosive blast in the hole includes (a) an explosion trigger (15, 19) for triggering the explosive in the hole, (b) a detonation unit body (21) that is configured to be located at or proximate an open end of the hole in an initial position of the assembly in the hole and (c) a trigger cord (31) that is connected to the detonation unit body and to the explosion trigger.

Abstract: A charge canister for a perforation tool has a cylindrical body with an expansion portion extending along a radius of the cylindrical body, the expansion portion having a narrow portion at a first end of the expansion portion and a wide portion at a second end of the expansion portion opposite from the first end. An explosive material is disposed within the expansion portion in direct contact with an interior surface thereof.

Abstract: Explosive devices may be formed from hollow members filled with explosive materials. The hollow members may be made of mating halves that are packed or loaded with explosive material prior to the mating halves being joined together. In some exemplary aspects, the hollow members are placed in fluid-filled containers such that the explosive reaction creates a wave of fluid that impacts a target. Components of the devices may be COTS items and items that may be manufacture with 3D printers.

Abstract: A well system includes a perforating gun having shaped charges and a detonator to controllably detonate the shaped charges. The well system further includes a propulsion head coupled to the perforating gun. The propulsion head is operable to apply thrust to the perforating gun such that the well system is self-propelling.

Abstract: A method of deactivating an explosive composition provided in an explosive cartridge, which method comprises exposing the explosive composition to a deactivating agent that renders the explosive composition insensitive to detonation, wherein the deactivating agent is a chemical.

Abstract: A high energy pipe severing tool is arranged to align a plurality of pressure balanced explosive pellets along a unitizing central tube that is selectively separable from a tubular external housing. The explosive pellets are loaded serially in a column and in full view along the entire column as a final charging task. Detonation boosters are pre-positioned and connected to detonation cord for simultaneous detonation at opposite ends of the explosive column. Devoid of high explosive pellets during transport, the assembly may be transported with all boosters and detonation cord connected.

Abstract: A liquid-jacketed disrupter comprising a container (101) for receiving liquid and housing a receptacle (120) for explosive material, in which the container comprises one or more indentations (115) which result in the generation of liquid jets upon detonation.

Abstract: An explosive booster assembly (70) which includes a primary module (10) with a first housing (12) and a first booster (14), wherein a detonator (62) is engageable with the first housing, and an auxiliary module (30, 30A) which comprises a second housing (32) with a second booster composition (34), wherein the second housing (32) is interengageable with the first housing (12) to expose the first booster composition (14) to the second composition (34), and wherein any number of substantially identical auxiliary modules (30, 30A) are engageable with one another in order to form a compound booster assembly.

Abstract: A booster shell, comprising: an elongate body defining a chamber for an explosive composition, the body comprising an upper end and a lower end; an inlet at the upper end of the elongate body adapted to allow an explosive composition to be delivered into the chamber; a detonator receiving passage adapted to receive a detonator, the detonator receiving passage: (a) extending within the chamber from the upper end of the elongate body to the lower end of the elongate body; (b) being integrally formed with the elongate body; and (c) including a detonator stop at or near to the lower end of the elongate body; and a detonator lead guide adapted to receive the lead of a detonator, the detonator lead guide: (a) extending from the upper end of the elongate body to the lower end of the elongate body and (b) being integrally formed with the elongate body.

Abstract: A pipe severing tool is arranged to align a plurality of high explosive pellets along a unitizing central tube that is selectively separable from a tubular external housing. The pellets are loaded serially in a column in full view along the entire column as a final charging task. Detonation boosters are pre-positioned and connected to detonation cord for simultaneous detonation at opposite ends of the explosive column. Devoid of high explosive pellets during transport, the assembly may be transported with all boosters and detonation cord connected.

Abstract: This invention relates to the oil and gas industry and to exploration and production of water resources, in particularly, for stimulation of fluid flow to the well, e.g., for higher oil production, productivity index, and recovery factor. The disclosed device and method can be used for higher permeability of the pay zone due to creation of a network of microcracks in the bottomhole formation zone and facilitates to increase the flow of oil, or other fluids, from the reservoir to the well. Generation of cyclic pressure pulses with varied amplitude and time parameters and proper localization of pulses in space through mechanism of convective combustion provides a “soft” impact upon the wellbore without risk of damage or formation consolidation; the said impact is achieved by using a device which is a downhole cyclic pressure generator operating by a consecutive combustion of layers of compositions having different combustion rates.

Abstract: An apparatus and method for selectively varying the yield of an explosive device is provided. The apparatus generally comprises a main charge that may selectively be consumed and/or detonated to achieve the selected yield ranging from about 0% to about 100%.

Abstract: Mining operations frequently involve the use of electric or electronic delay detonators in operative association with an explosive charge contained in a booster. Disclosed herein are connectors for connecting a signal transmission line to a detonator associated with a booster. In this way, the connectors, at least in preferred embodiments, allow the production of a substantially sealed booster assembly having a secure electrical connection to a signal transmission line. Also disclosed are methods of producing substantially sealed booster assemblies, and methods for their use in mining operations.

Abstract: Embodiments disclosed include a high-energy gas fracture apparatus for through-tubing operation. The apparatus includes a blast head, a fracturing body connected-with the blast head and an electric detonator provided in the blast head, the fracturing body having a central pipe sleeved by a fracture charge column outside and containing an explosive fuse sleeved by tubular igniting charge column inside. In an embodiment, charge amount per unit is effectively enhanced due to bared fracture charge column without sheath combustion gas peak pressure is reached quickly and therefore energy utilization rate during fracturing is effectively enhanced because of igniting by explosion energy of explosive fuse and combustion energy of igniting charge. Various embodiments are usable for fracturing or plug removal in a well without tubing.

Abstract: An apparatus for use in a wellbore comprises a heat insulating container having an inner space and having a structure defining a hollow containing a vacuum. The apparatus further comprises a reflective layer arranged on a surface of the heat insulating container to reflect heat for reducing radiated heat originated in the wellbore from reaching the inner space. Also, a signal-activated detonator is provided in the inner space of the heat insulating container.

Abstract: The present invention relates to apparatus and methods to stimulate subterranean production and injection wells, such as oil and gas wells, utilizing rocket propellants. Rapid production of high-pressure gas from controlled combustion of a propellant, during initial ignition and subsequent combustion, together with proper positioning of the energy source in relation to geologic formations, can be used to establish and maintain increased formation porosity and flow conditions with respect to the pay zone.

Abstract: An apparatus for use in a wellbore comprises a heat insulating container having an inner space and having a structure defining a hollow containing a vacuum. The apparatus further comprises a reflective layer arranged on a surface of the heat insulating container to reflect heat for reducing radiated heat originated in the wellbore from reaching the inner space. Also, a signal-activated detonator is provided in the inner space of the heat insulating container.

Abstract: Mining operations frequently involve the use of electric or electronic delay detonators in operative association with an explosive charge contained in a booster. Disclosed herein are connectors for connecting a signal transmission line to a detonator associated with a booster. In this way, the connectors, at least in preferred embodiments, allow the production of a substantially sealed booster assembly having a secure electrical connection to a signal transmission line. Also disclosed are methods of producing substantially sealed booster assemblies, and methods for their use in mining operations.

Abstract: A shaped charge detonation booster comprises a tubular wall body of substantially constant outside diameter for enclosing an axial primer path that terminates with an enlarged main cavity volume. Preferably, the main cavity is positioned within the juncture plane of opposing shaped cutter charges. The tubular wall surrounding the primer path is substantially thicker than the tubular wall surrounding the main body and the explosive material within the main body is compacted more densely than the explosive material in the primer path.

Abstract: A system for fracturing wells uses a primary propellant charge to initially produce pressures within the well in excess of the maximum fracture extension pressure of the surrounding formation, but below that which would cause damage to the well. A supplemental propellant charge burns for a substantially longer period of time than the primary propellant charge, and thereby maintains pressures within the well in excess of the maximum fracture extension pressure for a significant period of time following completion of the primary propellant burn.

Abstract: A shaped charge tubing cutter includes a minimal contact suspension to isolate the cutter explosive from the housing and sub structure. A charge detonation booster main-cavity is located on the juncture of the charge truncation planes. Explosive in the booster main-cavity is detonated by a shielded primer path. Explosive density in the primer path is less than the main-cavity density. A dense, powdered metal SC liner and an abruptly stepped jet window in the tubing cutter housing improve performance. The axial span of the jet window is preferably aligned with the axial span between the liner bases. A testing apparatus and procedure inexpensively verifies downhole performance.

Abstract: A segmented explosive device capable of producing a shock wave front upon being exploded by a detonation impulse generated by a selectively operable control device and communicated to the explosive device by a transmission line coupled between the control device and the explosive device. The explosive device has a first charge segment and a second charge segment disposed in an assembled relationship. The first charge segment has a first abutment surface formed on a portion of the exterior thereof and a cavity recessed in the first abutment surface. An output end of the transmission line is received by the cavity and contacts the first charge segment. The cavity of the first charge segment can be configured to dispose explosive material in the path of a plasma zone propagating through voids internal of the explosive device to facilitate advance detonation of the explosive material before a shock wave front trailing the plasma zone reaches the explosive material.

Abstract: A method and apparatus to protect explosive components used in various tools, such as tools for use in wellbores, includes a component with an adsorptive material. Example tools include perforating gun strings that include shaped charges, detonating cords, and booster explosives. Other tools may include surface tools containing explosive components. The adsorptive material is placed inside a container. A temperature-activated mechanism is used to open the container. The temperature-activated mechanism includes an element formed of a shape memory metal or plural layers with different coefficients of thermal expansion, such as a bi-metallic strip.

Abstract: An explosive charge such as a cast booster charge (10, 110, 210) includes an explosive charge (14, 114, 214) having a first explosive matrix material (114a, 214a) with discrete bodies (118, 218) of a second material embedded therein. In some embodiments, discrete bodies may comprise explosive material and the first explosive matrix material (114a, 214a) may be more sensitive to initiation than the explosive material of the discrete bodies (118, 218). In a separate aspect of the invention, the discrete bodies may have a minimum dimension of at least 1 millimeter or, optionally, 1.6 millimeter, regardless of the explosive properties of the material therein. In a particular embodiment, discrete bodies may be shaped as cylindrical pellets rounded at at least one end. The cast booster charge (10, 110, 210) may be produced by melting the first explosive, disposing discrete bodies therein and cooling the molten material to solid form.

Abstract: A shock tube connector system comprises a substantially cylindrical detonator having a longitudinal axis a block body receiving the detonator therein, and an end cap. The detonator includes an axisymmetric exterior shell including a cylindrical main section, a cylindrical explosive end portion having a diameter less than the diameter of the main section, and a transition portion connecting the main section and the explosive end portion of the shell. An explosive charge is contained within the explosive end portion of the shell and is distributed along the longitudinal length of the explosive end portion. The explosive charge preferable comprises two portions of lead azide or a first charge portion of lead azide and PETN and a second charge portion of PETN. An initiating shock tube is operatively connected to the explosive charge via a delay element. The block body includes a housing within which the main section of the detonator is received.

Abstract: A shock tube connector system comprises a substantially cylindrical detonator having a longitudinal axis a block body receiving the detonator therein, and an end cap. The detonator includes an axisymmetric exterior shell including a cylindrical main section, a cylindrical explosive end portion having a diameter less than the diameter of the main section, and a transition portion connecting the main section and the explosive end portion of the shell. An explosive charge is contained within the explosive end portion of the shell and is distributed along the longitudinal length of the explosive end portion. The explosive charge preferable comprises two portions of lead azide or a first charge portion of lead azide and PETN and a second charge portion of PETN. An initiating shock tube is operatively connected to the explosive charge via a delay element. The block body includes a housing within which the main section of the detonator is received.

Abstract: A method and apparatus to protect explosive components used in various tools, such as tools for use in wellbores, includes a component with an adsorptive material. Example tools include perforating gun strings that include shaped charges, detonating cords, and booster explosives. Other tools may include surface tools containing explosive components. In these tools, a build up of corrosive gases or liquids may occur, which may cause damage to the explosive components. As a result, the structural integrity or reliability and thermal stability may be weakened or reduced. To reduce the amount of build up of corrosive gases or liquids, an adsorptive material is placed inside tools in the proximity of explosive components.

Abstract: A shock tube connector system comprises a substantially cylindrical detonator having a longitudinal axis a block body receiving the detonator therein, and an end cap. The detonator includes an axisymmetric exterior shell including a cylindrical main section, a cylindrical explosive end portion having a diameter less than the diameter of the main section, and a transition portion connecting the main section and the explosive end portion of the shell. An explosive charge is contained within the explosive end portion of the shell and is distributed along the longitudinal length of the explosive end portion. The explosive charge preferable comprises two portions of lead azide or a first charge portion of lead azide and PETN and a second charge portion of PETN. An initiating shock tube is operatively connected to the explosive charge via a delay element. The block body includes a housing within which the main section of the detonator is received.

Abstract: Migration of Di-Octyl Adipate (DOA) from PBXN-9 main charge into an adjacent PBXN-5 booster charge is the leading cause for unreliable and inefficient detonations when these two insensitive munition explosives are in close proximity. A hermetic seal of metal foil is interposed between the booster and main charges to block migration of DOA chemicals between the charges. This prevents plasticizing and/or desensitizing the booster charge and possible catastrophic accidental detonations or highly undesirable explosive desensitization which might create unexploded ordnance. The hermetic seal may also have a first portion of metal foil covering the surface of a bore in the booster charge and second portions of metal foil covering the surface of bores in the main charge.

Abstract: As has been established, the use of energetic materials, generated by manufacturer's excess and/or demilitarization projects, as ingredients in commercial blasting explosives is a feasible and environmentally acceptable method of handling them. Ammonium picrate is used as an explosive charge in the manufacturing of conventional ammunition rounds, such as large caliber navy guns. The present invention is directed to the use of recovered ammonium picrate in commercial blasting agent compositions, that include watergel slurries, ANFO, HANFO-blends and emulsion based blasting agents. These new blasting agents exhibit favorable cost for performance characteristics and have found a use for recovered ammonium picrate, which would heretofore have been incinerated or otherwise disposed of at significant cost.

Abstract: An explosives booster (10) intended for igniting a main explosive charge is provided which includes a first explosive charge (15) which is sensitive enough to be ignited by the explosion of a charge from a detonator (13); and a second explosive (16) charge which is less sensitive to ignition that the first charge, (15) but more sensitive to ignition than the main charge. The first charge may comprise a 60/40, and the second charge a 40/60, PETN/TNT pentolite mixture.

Abstract: The invention relates to an explosives booster (1) which can substantially enclose a detonator (2) and which comprises an integral fastening means (10) for positive retention of non-electric tubing (3) attached to the detonator (2). The primer formed by the combination of said booster and non-electric detonating assembly has improved handling characteristics and can better withstand rough handling.

Abstract: A propellant igniter assembly includes a housing having ignition channels for the passage of an ignition flame through the housing; an igniter part accommodated in the housing; and a booster part accommodated in the housing and frontally adjoining the igniter part. The booster part has a booster charge which includes a first partial booster charge adjoining the igniter part and composed of a readily ignitable substance and a second partial booster charge adjoining the first partial booster charge and being separated thereby from the igniter part. The second partial booster charge entirely obturates all the ignition channels. The second partial booster charge has a burning behavior and a mechanical stability such that the ignition channels remain obturated for a short duration even after ignition of the second partial booster charge, whereby a firing impact is first retained in the booster part and is subsequently abruptly released in a concentrated form through the ignition channels.

Abstract: A booster explosive device (10) has a housing (12) within which is contained an explosive primer charge (14). Mechanical fastener components such as exterior screw threads (32) on housing (12) and interior screw threads (34) on an explosive accessory charge (20) may be engaged with each other in order to provide a charge assembly (30) comprised of device (10) and accessory charge (20). The outer peripheral surface (26) of accessory charge (20) is optionally concave so that accessory charge (20) optionally serves as a shaped charge to provide enhanced radial explosive output. Explosive primer charge (14) is configured so that the output tip (44b) of a detonator (44) contained therewithin is positioned below at least about 50 percent by weight of primer charge (14) and within the accessory section (10c) of device (10).

Abstract: A detonation system especially useful for initiating a plurality of substantially simultaneous seismic detonations includes an electric trunkline circuit disposed on the surface of a firing site containing boreholes, within which booster charges having respective top and base portions are disposed. The booster charges are connected without intervening detonators to the downhole ends of equal-sized lengths of low-energy detonating cord, the surface ends of which are connected to semiconductor bridge-initiated electric detonators connected in series in the firing circuit. The resulting system, because of the small deviation in function time of the semiconductor bridge detonators, has greatly reduced scatter time as compared to prior art systems utilizing conventional downhole electric detonators, and has a safety advantage in that the boreholes are free of detonators.

Abstract: A system for initiating shock tube which has a low cost of manufacture, is relatively impervious to moisture, and initiates the shock tube reliably is described. The initiating system comprises a thermal input initiator device, a thermal enhancing output device, and a length of shock tube. The thermal input initiator device converts the thermal flame energy to percussive energy that travels as a signal wave along the shock tube at a speed of 6500 ft/sec. The signal wave hits the thermal enhancing output device and is converted back into thermal energy that is capable of reliably initiating display fireworks.

Abstract: A method and apparatus for transferring non-electric blasting initiation signals from detonating cord signal donor lines to signal transmission tube acceptor lines involves disposing the acceptor line in enhanced signal transfer configuration with the donor line. The acceptor line (30) may constitute the input lead (29a) of a detonator (10a). Enhanced signal transfer configuration between the input lead (29a) and the detonating cord (60) can be established by disposing input line (30) in at least partial wrap-around contact with the detonating cord (60) or in multiple abutting contact with the detonating cord (60). Enhanced signal transfer configuration can also be achieved for a detonator having at least two input lines in abutting contact with the detonating cord. A slider (44) is designed to extend contact between a detonator input lead and a detonating cord.

Abstract: A slider (36) has a base fixture (40) and a shielding tube (42). The slider (36) is used to operably couple a detonator (44) to a detonating cord (62) that passes through a booster device (10), i.e., to prevent the detonating cord (62) from directly initiating or fracturing the booster (10). The base fixture (40) includes input lead-retaining means for disposing the input lead (47) of a detonator (44) in signal transfer relation to the detonating cord (62). Optionally, the slider (36) has a detonator retainer (38) for carrying the detonator (44) on the slider (36). Preferably, the detonator retainer (38) is able to hold detonators of various lengths in proper position to initiate the booster device (10). By disposing the shielding tube (42) on the slider (36) a booster device (10) can be used with various detonating cords (62) and a slider (36) having a shielding tube (42) suitable for the chosen detonating cord (62) can be inserted into the booster device (10).

Abstract: An accessory charge (20) for mounting on a booster explosive device (10) is preferably of toroidal configuration including a hub opening (29) dimensioned and configured to engage the accessory charge (20) with the booster device (10). The booster device (10) may have exterior threads (32) which are engaged by the interior threads (34) of the accessory charge (20). The outer peripheral surface (26) of the accessory charge (20) may be concave in cross section so that the accessory charge (20) comprises a shaped charge facing radially outwardly thereof. The accessory charge (20) may be combined with the booster device (10) to provide a charge assembly (30).

Abstract: A shaped charge includes a main body of explosive and a primer adapted to detonate said main body of explosive. In accordance with the present invention, the main body of explosive now includes an explosive composition known as sym-triaminotrinitrobenzene (TATB) and, since TATB is not sensitive enough to be a primer, the primer must consist of an explosive composition which is more sensitive than TATB. It has been discovered that, when the main body of explosive in a shaped charge is modified to include the explosive composition known as TATB and when the primer includes an explosive other than TATB, such as HNS or NONA or PYX or HMX, or a mixture of HNS or NONA or DODECA or PYX or HMX and TATB and when the shaped charge is detonated, the detonated charge will produce a jet that is longer in length than the jet associated with prior art shaped charges which did not have a main body of explosive that included TATB.

Abstract: The present invention is directed to an improved connector comprising a first and second holding means for pressure fitting a detonating cord and shock tube in a substantially orthogonal pressure fitting relationship.

Abstract: The present invention describes a method of using 1.1 solid rocket propellant in the detonation process for explosives. The use of the 1.1 solid rocket propellant is described as a booster for use in a blasting cap.

Abstract: A detonator assembly is provided which increases versatility, reliability and safety by initiating any amount of signal transmission lines up to about 8 without emitting excessive noise or shrapnel which can cause cut off or safety hazards. The detonator assembly comprises a low strength detonator with a single charge of preferably lead azide. A high confinement connection block houses the low strength detonator and comprises a retention block in which the low strength detonator is inserted and a confining wall which surrounds the closed end of the low strength detonator. One to about eight signal transmission lines can be inserted through a gap in the confining wall and operatively confined adjacent the closed end of the low strength detonator.

Abstract: The device (10) consists of a bar (12) of high explosive having a planisymmetrical groove (20) along one side lined with a hollow charge liner (28). A pair of backing charges (34, 36) connected by a bridging charge (42) are disposed along the opposite side of the bar. Each backing charge is separated from the bar by a gap (38, 40) which tapers towards the common longitudinal periphery of the bar and charge. The surfaces of the backing charges facing the gaps are lined with liners (46, 48). A linear initiating charge (54) is separated from the bridging charge longitudinally of the device by a gap (61). The facing surface of the charge (54) is lined with a metal strip (58) which, when the charge is detonated, is projected across the gap (61) to initiate the bridging charge linearly. A detonation wave then propagates from the bridging charge down each backing charge towards its peripheral region, projecting the liners (46, 48) across the gaps (38, 40) to initiate the bar.

Abstract: A method of blasting cap-sensitive, non-nitroglycerine-sensitized explosives and an initiating assembly for use in the method are provided. The method comprises initiating a column of the explosives by directing two radial/forward shock forces from an initiator assembly substantially simultaneously along the column of the explosives towards each end of the column. The initiating assembly of the invention comprises at least two initiators assembled side-by-side so that their explosive ends are opposite. A moulded plastics holder (6) for holding two blasting caps (1, 8) in the required spatial relationship is also described.

Abstract: A primer for an explosive charge which is to be initiated by a fuse cord is sensitized by a loose charge of a high explosive, this high explosive being contained in a rigid, impermeable container which is so shaped that at least partially surrounds the fuse cord. The container is of plastics or metal and preferably comprises at least one elongated concave surface which mates with and is supported by at least one metal rod which protrudes from the base of a mold in which the primer will be cast and which establishes a channel for a fusecord.The primers of this invention have more sensitivity and robustness than known primers, and wire fusecords of lower charge weight.

Abstract: A booster for high efficiency initiation of an explosive material comprising a body portion having substantially tapered sides and a substantially flat interface surface at the larger end of the body portion extending generally laterally thereof for contacting the explosive material. A plurality of passageways may be formed in the booster to receive a means for detonating same. When compared with traditional cylindrical boosters of either equal weight or equally sized interface surfaces, the disclosed booster resulted in shorter run-up distance and a more effective release of explosive energy. Although numerous geometric configurations of the booster are disclosed, a presently preferred embodiment thereof takes the shape of a conical frustum, the larger planar surface of which is to be oriented as the interface surface toward the explosive material to be detonated.

Abstract: An ignition transfer body for a propellant-charge module is coaxially surrounded by a supporting tube and includes at least one clear ignition channel. The ignition transfer charge is composed of a first propellant-charge powder generating thermal energy in a range of 3 kJ/g to 4.5 kJ/g, and the supporting tube is composed of a second propellant-charge powder. Preferably, the second propellant-charge powder forming the supporting tube is pressed powder which is extruded or pressed in a mold.

Abstract: In the inventive shaped charge, the main charge and the propagating charge are held together solely by the barrier. This union is possible (and is distinguished by pronounced freedom from flaws) because the barrier is produced directly in the cavity in which it is to remain and is able to conform with the utmost accuracy to the surfaces of the charges. The barrier is advantageously formed under vacuum. Factors to be considered in the selection of the barrier material are its fluidifiability, its solidification and shrinkage behavior, and its compatibility with the explosive. Suitable barrier materials include single- or two-component foams, casting compounds, resins and adhesives.