425results about "Explosive charges" patented technology

A method for intercepting and a defeating rocket propelled grenade (RPG) which includes the steps of detecting a thermal signature from a launch of the RPG; and cueing a narrow beam radar which locates the RPG and develops a ballistic solution and target intercept point for intercepting the PPG with an intercept vehicle.

A chemical reaction between molten aluminum and an oxygen carrier such as water to do useful work is disclosed, and in particular two chemical methods to obtain aluminum in its molten state. One is to detonate a HE / Al mixture with surplus Al in stoichiometry, and the other is to use an oxidizer / Al mixture with surplus Al in stoichiometry. Additionally, there is a physical method of shocking and heating Al using high temperature reaction products. The produced Al in its liquid form is forced to react with an oxygen carrying liquid (e.g. water), giving off heat and releasing hydrogen gas or other gaseous material. A water solution of some oxygen-rich chemicals (e.g. ammonium nitrate) can be advantageously used in place of water. A shaped charge is also disclosed having a liner that contains aluminum, propelled by a high explosive such as RDX or its mixture with aluminum powder. Some aluminum in its molten state is projected into the perforation and forced to react with water that also enters the perforation, creating another explosion, fracturing the crushed zone of the perforation and initializing cracks. Another shaped charge is shown having a liner of energetic material such as a mixture of aluminum powder and a metal oxide. Upon detonation, the collapsed liner carries kinetic and thermal energy. Also shown are methods to build and to detonate or fire explosive devices in an oxygen carrying liquid (e.g. water) to perforate and stimulate a hydrocarbon-bearing formation.

A solid object having controlled frangibility, such as a bullet or a container for explosives, is made by combining two different metals in proportions calculated to achieve a desired density, without using lead. A wetting material is deposited on the base constituent which is made of a relative dense, hard material. The wetting material enhances the wettability of the base constituent with the binder constituent, which is lighter and softer than the base constituent.

A shaped charge includes a charge case; a liner; an explosive retained between the charge case and the liner; and a primer core disposed in a hole in the charge case and in contact with the explosive, wherein at least one of the case, the liner, the primer core, and the explosive comprising a material soluble in a selected fluid. A perforation system includes a perforation gun, comprising a gun housing that includes a safety valve or a firing valve, wherein the safety valve or the firing valve comprises a material soluble in a selected fluid.

The invention provides shock initiation devices comprising multilayer structures with constituent layers that undergo an exothermic self-propagating reaction once initiated by shock. The multilayer structures may be used as components in shaped charges, EFP devices, warheads, munition casings, interceptors, missiles, bombs, and other systems. The reactive layer materials may be selected based on required structural properties, density and reaction temperature.

A shaped charge comprises a shell, an explosive charge disposed inside the shell, and a first liner for retaining the explosive charge within the shell. The shaped charge further comprises an acid material disposed inside the shell on the first liner and retained by a second liner into the shell.

A shaped charge liner formed by injection molding, where the liner components include powdered metal and organic binder. The liner components are blended then processed within an injection molding device and urged from the molding device into a mold where a liner shape is formed. The liner shape is debinded, both mechanically and chemically. Mechanical debinding involves heating and chemical debinding comprises treating the liner shape with a solution to dissolve and remove the binder components. The process of forming the shaped charge liner does not include sintering. The present process can also use “green products” formed by the injection molding device that are not debinded. A shaped charge case can also be formed using the present method. The added step of sintering can be applied to the process of forming the shaped charge case.

An end plate for securing and orienting a charge tube within a downhole-perforating gun. The end plate includes apertures for receiving locating tabs on the end of the charge tube to ensure the end plate is affixed to the charge tube in a specific orientation. The end plate includes an alignment tab that mates with a corresponding alignment groove in the perforating gun barrel for ensuring insertion of the charge tube into the perforating gun barrel in correct orientation to ensure the perforating charges exit through pre-designed scallops in the perforating gun barrel. A series of apertures may be present within the end plate to allow usage with one of a variety of sizes of charge tube. The end plate may include manipulation spaces along the circumference of the end plate to allow the end plate to be properly positioned or retrieved. The end plate may include an attachment system for attachment of an initiating device.

A casing cutting and recovery tool having a cutting assembly, an expansion assembly having one or more deforming members, and a recovery assembly is used to cut a window in wellbore casing, secure a removable segment of wellbore casing that was previously disposed within the window, and recover the removable segment of wellbore casing with the tool. One or more cutting assemblies provides one or more cuts in the wellbore casing. The deforming members of the expansion assembly then expand outwardly at least two portions of the wellbore casing shaped by the cut or cuts. The recovery assembly secures the removable segment of the wellbore casing to the tool so that the tool and the removable segment of wellbore casing can be recovered together from the wellbore.

An oil and gas well shaped charge perforator capable of providing an exothermic reaction after detonation is provided, comprising a housing, a high explosive, and a reactive liner where the high explosive is positioned between the reactive liner and the housing. The reactive liner is produced from a composition which is capable of sustaining an exothermic reaction during the formation of the cutting jet. The composition may be selected from any known formulation which is suitable for use in an oil and gas well perforator, typically the composition will comprise at least one metal and at least one non-metal, wherein the non-metal is selected from a metal oxide, or any non-metal from Group III or Group IV or at least two metals such as to form an intermetallic reaction. Typically at least one of the metals in the invention may be selected from Al, Ce, Li, Mg, Mo, Ni, Nb, Pb, Pd, Ta, Ti, Zn or Zr. The liner composition may preferably be a pressed particulate composition, such that the material is consolidated under pressure to form the desired shape of the liner. To aid consolidation a binder may also be added.

A perforating gun assembly useful in hydrocarbon well completion. The gun is assembled in a carrier made from straight walled tubing as a primary structural member with complementary male and female threads cut into opposite ends so that gun assemblies may be directly connected together. The male coupling includes a reinforcing sleeve threaded into an internal thread. An alignment pin is positioned in the carrier extending through the reinforcing ring and into the interior of the carrier. A charge assembly includes a charge holder tube with upper and lower alignment fixtures. The lower alignment fixture includes an alignment slot for mating with the alignment pin and a shoulder for supporting the charge assembly on the sleeve. The upper alignment fixture has an alignment pin for mating with an alignment slot in the carrier. A retainer ring may be threaded into the upper female threads to prevent removal of the charge assembly from the carrier.

A shaped charge and a method of using such to provide for large and effective perforations in oil bearing sandy formations while causing minimal disturbance to the formation porosity is described. This shaped charge uses a low-density liner having a filler material that is enclosed by outer walls made, preferably, of plastic or polyester. The filler material is preferably a powdered metal or a granulated substance, which is left largely unconsolidated. The preferred filler material is aluminum powder, or aluminum particles, that are coated with an oxidizing substance, such as TEFLON®, permitting a secondary detonation reaction inside the formation following jet penetration. The filled liner is also provided with a metal cap to aid penetration of the gun scallops, the surrounding borehole casing and the cement sheath. The metal cap forms the leading portion of the jet, during detonation. The remaining portion of the jet is formed from the low-density filler material, thereby resulting in a more particulated jet. The jet results in less compression around the perforation tunnel and less skin damage to the proximal end of the perforation tunnel.

Shaped charge assembly for use as part of a perforating gun, particularly, channel finder gun. The shaped charge assembly includes a charge is configured to produce a jet which is substantially non-circular in cross section (in relation to the axial direction of travel of the jet) in which the assembly includes a base that is relatively rigid with respect to the liner of the assembly.

A system and method for making and using a multi-point initiation explosive device that produces an enhanced pressure wave for severing tubing, pipe or casing in an oil or gas well. At least two opposed initiators initiate a column of explosive material from opposite ends, thereby generating opposing pressure waves propagating toward a midpoint between the initial initiators. A shaped-charge assembly with a liner located at the midpoint initiates immediately prior to the arrival of the opposing pressure waves and forms a fast moving jet to pre-score the target pipe prior to the arrival of the pressure pulse propagating from the initial detonations.

A loading tube for installation in the body of a perforating gun is disclosed. The loading tube holds a plurality of shaped charges whose detonation is electrically initiated, and the loading tube, when installed in the body, comprises at least a portion of the electrical circuit used to initiate detonation the shaped charge. In one embodiment, the loading tube comprises the hot portion of the electrical circuit, the body comprises the ground portion of the electrical circuit and the loading tube and the body are insulated from one another. Alternatively, the loading tube may comprise two distinct portions of conductive material which are electrically isolated from one another where the two portions of conductive material comprise the hot and ground portions of the electrical circuit. Additionally, a loading tube according to the present invention may comprise a conductor which is disposed in the loading tube near the outer surface of the loading tube and which is insulated from the loading tube. A system is disclosed comprising a loading tube having the aforesaid characteristics and a method is provided which utilizes the loading tube as a portion of the electrical circuit to initiate detonation of the charges.

A non-linear shaped charge perforator for use in perforating an oil and gas formation into which a wellbore has been drilled comprises a monolithic, axisymmetric metal case in which is disposed a main explosive charge between the front of the case, which is closed with a concave metal liner, and the closed back end of the case. The main explosive charge contains multiple initiation points, preferably two initiation points located about 180° apart on the outside surface of the charge, so that when the perforator is detonated the main charge is initiated such that the metal liner is collapsed into a non-circular jet, preferably a fan-shaped jet, that pierces the casing of the wellbore and forms non-circular perforations, preferably slot-shaped perforations, in the surrounding formation.

A multi-shot explosive charge includes a plurality of chambers divided by shared walls between adjacent chambers. Explosive material within at least one of the chambers creates an explosive force in an outward direction upon detonation and a perforating jet through the open end of the chamber. A perforating charge includes at least one explosive material producing explosive forces, upon detonation that collide within the chamber to create a perforating jet. Such perforating charge may be a chamber(s) within a multi-shot explosive charge, or an individual charge. First and second explosive materials can have the same or different compositions and detonation rates that together with the arrangement of materials within the chamber create the collision of forces. A plurality of multi-shot explosive charge or stand-alone perforating charges with colliding forces can be interconnected in an array, and can be included in a perforating gun(s).

A perforating gun assembly for use in a wellbore. The perforating gun assembly includes a carrier gun body and a charge holder disposed within the carrier gun body. A plurality of shaped charges are supported within the carrier gun body. A secondary pressure generator is operably associated with at least one of the shaped charges. The secondary pressure generator optimizes the wellbore pressure regime immediately after detonation of the shaped charges by controlling the dynamic underbalance created by the empty gun chambers to prevent excessive dynamic underbalance which may detrimentally effect the perforating operation.

A lead free ferromagnetic article is disclosed. The article is a compacted composite having a heavy more dense constituent that is preferably ferrotungsten and a less dense second constituent that is either a metal alloy or a polymer. The ferromagnetic constituent is present in an amount sufficient to impart the article with ferromagnetism. The ferromagnetic property allows fragments of the article, such as a projectile, bullet or shaped charge liner to be separated from dirt or other environments.

A liner for a shaped charge comprising powdered heavy metal tungsten coated with a metal binder coating compressively formed into a liner body. Each of the powdered heavy metal particles are substantially uniformly coated with metal binder coating. The preferred powdered heavy metal particles are comprised of tungsten. Optionally, the liner for a shaped charge includes a lubricant intermixed with the coated heavy metal particles. The metal binder coating is selected from the group consisting of copper, lead, nickel, tantalum, other malleable metals, and alloys thereof, and comprises from 40 percent to 3 percent by weight of the liner. The powdered heavy metal particles comprise from 60 percent to 97 percent by weight of the liner.

A perforating apparatus (100) includes a plurality of shaped charges (102) each having an initiation end and a discharge end. A detonating cord (116) is operably coupled to the initiation ends of the shaped charges (102). A carrier (106) contains the shaped charges (102). The carrier (106) includes at least one discharge location corresponding to the discharge ends of the shaped charges (102) when the perforating apparatus (100) is in its operable position. The discharge location has first and second material layers (122, 124) wherein the second material layer (124) exhibits resilient recovery such that an opening created by a jet formed from detonating one of the shaped charges (102) in the second material layer (124) is smaller than an opening created by the jet in the first material layer (122), thereby retaining debris in the perforating apparatus (100) with the second material layer (124).

By removing material of low permeability from within and around a perforation tunnel and creating at least one fracture at the tip of a perforation tunnel, injection parameters and effects such as outflow rate and, in the case of multiple perforation tunnels benefiting from such cleanup, distribution of injected fluids along a wellbore are enhanced. Following detonation of a charge carrier, a second explosive event is triggered within a freshly made tunnel, thereby substantially eliminating a crushed zone and improving the geometry and quality (and length) of the tunnel. In addition, this action creates substantially debris-free tunnels and relieves the residual stress cage, resulting in perforation tunnels that are highly conducive to injection under fracturing conditions for disposal and stimulation purposes, and that promote even coverage of injected fluids across the perforated interval.

A spontaneous firing explosive composition for use in a gas generator for an airbag containing a fuel, an oxidizer, a combustion modifier, and a binder.

The present invention is concerned with severing tubing, pipe or casing in an oil or gas well, and more particularly with a system and method for making and using a multi-point initiation explosive device that produces an enhanced pressure wave for severing tubing, pipe or casing in an oil or gas well. One embodiment uses at least two opposed initiators to initiate a column of explosive material from opposite ends, thereby generating opposing pressure waves propagating toward a midpoint between the initial initiators and a shaped-charge assembly with a liner located at the midpoint that initiates immediately prior to the arrival of the opposing pressure waves and that is intended to form an initial, fast moving jet to pre-score the target pipe prior to the arrival of the pressure pulse propagating from the initial detonations.

A perforating gun assembly for use in a wellbore. The perforating gun assembly includes a carrier gun body and a charge holder disposed within the carrier gun body. A plurality of shaped charges are supported within the carrier gun body. A secondary pressure generator is operably associated with at least one of the shaped charges. The secondary pressure generator optimizes the wellbore pressure regime immediately after detonation of the shaped charges by controlling the dynamic underbalance created by the empty gun chambers to prevent excessive dynamic underbalance which may detrimentally effect the perforating operation.