423results 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.

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.

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 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 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.

The present invention relates to methods and apparatuses for explosive breaching.