Abstract: A method of removing material from a target is described. The method comprises the steps of providing a tool, the tool having at least one propellant source; pressurising the tool to a pressure higher than the environmental pressure; igniting at least one of the propellant source(s) to form a combustion zone; and directing combustion products generated at the combustion zone along at least one tool flow path. The tool flow path(s) is selectively openable or closable, such that upon exiting the tool flow path(s) the combustion products interact with a target, the interaction causing material to be removed from the target.

Abstract: A downhole sealing apparatus comprises a propellant section and a sealing element section adjacent the propellant section. The propellant section comprises an outer housing, at least one propellant structure within the outer housing, and at least one initiator device adjacent the at least one propellant structure. The sealing element section is configured to isolate a region of a borehole in a subterranean formation responsive to pressure of gases produced through combustion of at least one propellant of the at least one propellant structure of the propellant section. A downhole assembly and a method of isolating portions of a borehole in a subterranean formation are also disclosed.

Abstract: A method of removing material from a target is described. The method comprises the steps of providing a tool, the tool having at least one propellant source; pressurising the tool to a pressure higher than the environmental pressure; igniting at least one of the propellant source(s) to form a combustion zone; and directing combustion products generated at the combustion zone along at least one tool flow path. The tool flow path(s) is selectively openable or closable, such that upon exiting the tool flow path(s) the combustion products interact with a target, the interaction causing material to be removed from the target.

Abstract: A method of manufacturing a premeasured compressed charge in which the compressed charge has a leading end portion with a smaller dimension than both a trailing end portion and a desired caliber of the intended firearm and the trailing end portion has a larger diagonal dimension than the desired caliber of the firearm. The method comprises the steps of providing a mold with cavities, filling the mold cavities with gunpowder, pressing gunpowder to form a compressed charge so that one of a density and a compaction of the gunpowder, adjacent the leading end portion of the compressed charge, is about 0% to about 5% less than the density or the compaction of the gunpowder adjacent the trailing end portion to facilitate a more complete combustion of the compressed charge upon discharge of the firearm, and removing the compressed charge from the cavities.

Abstract: A method for producing propellant charges with progressive combustion characteristic and a higher charge density than previously considered possible to achieve, intended in the first instance for direct-firing barrel weapons such as tank cannons. Combined in the charge are at least two radially perforated propellant tubes, which are arranged in their entirety inside or after one another, and which have at an e-dimension selected in relation to the actual type of propellant and its desired combustion characteristic, combustion or ignition channels, and which have circular outer and inner boundary surfaces, in conjunction with which, before initiation of the charge, at least one of the total number of outer surfaces of these propellant tubes that are available for initiation has been treated with an inhibition, surface treatment or surface intended to delay the propagation of ignition to that surface so that the combustion of the propellant tubes is partially mutually overlapping.

Abstract: A clean burning premeasured compressed charge for use in black powder firearms as well as cartridges. The premeasured compressed charge is manufactured to have a substantially desired shape which facilitates improved flame propagation by the leading end wall and along the exposed sidewall surfaces of the compressed charge to result in a more complete and rapid burning of the compressed charge both from the leading end wall toward the trailing end wall and also radially inwardly from each one of the four sidewalls toward a center of the premeasured compressed charge. The premeasured compressed charge has a leading end portion and a trailing end portion and the leading end portion is either the same size or a smaller dimension than the trailing end portion.

Abstract: The resent invention relates to a method for producing propellant charges with progressive combustion characteristic and a higher charge density than previously considered possible to achieve, intended in the first instance for direct-firing barrel weapons such as tank cannons.

Abstract: A gas generant material body in the form of a tablet having a triangular cross section and associated methods of gas generation are provided.

Abstract: A propellant system for launching a large-caliber projectile includes a propellant having at least three partial charges. The first partial charge is adapted to acceleration requirements of the projectile; the second partial charge has a higher combustion velocity than that of the first partial charge; and the third partial charge has a lower combustion velocity than that of the first partial charge. The propellant system further includes an electric energy supply and control device connected to the propellant for igniting the propellant. The electric energy supply and control device has a plasma generator for affecting a combustion behavior of the propellant such as to obtain for said first partial charge, after ignition of the propellant, a maximum gas pressure level of always the same magnitude independently from an initial propellant temperature, and to obtain, for the third partial charge, a conversion such as to prolong the maximum gas pressure level in a predeterminable manner.

Abstract: This invention relates to explosive charges in which the chemical and physical composition changes gradually from point to point in order to accomplish differing, specific design objectives. More specifically, the invention relates to an explosive comprised by uniformly mixing components of differing chemical and physical properties in order to take advantage of the functions performed by these different components resulting in an explosive capable of performing multiple or specific tasks.

Abstract: A propellant charge arrangement for barrel-weapons or ballistic drives comprises a conventional core charge having an ignition system and a consolidated propellant surrounding the core charge and having its own high electrical energy ignition system which can be controlled in a time-delayed manner after triggering the core charge ignition system. The structure and arrangement of the consolidated propellant and its ignition system are chosen such that, during combustion of the core charge, the consolidated propellant disintegrates into fragments of essentially uniform geometry in response to triggering of its associated ignition system, wherein the fragments are accelerated into the gas volume generated during combustion of the core charge.

Abstract: A dual explosive charge is described that simultaneously enhances blast and fragmentation characteristics of the charge, including an inner driven charge of a non-ideal explosive surrounded by an outer charge sleeve of a more nearly ideal explosive, detonation of the outer charge resulting in an extremely high temperature, high pressure environment that accelerates reaction kinetics in the inner charge, resulting in enhanced blast and fragmentation performance of the explosive charge.

Abstract: An ordnance or munition casing is described which comprises a hollow outer casing having a shock attenuating inner liner made from successive layers of material of inwardly decreasing acoustic impedance. The inner liner reduces the sensitivity of the munition to sympathetic detonation and cookoff. Also described is an attenuation barrier made from a layer or layers of less detonation sensitive explosive material. The layers of less detonation sensitive material are preferably arranged in successive layers of outwardly decreasing detonation sensitivity. The same layers may combine sequenced acoustic impedance and detonation sensitivity. The layers may be made of material compounded with flaked or granular materials to provide preselected acoustic impedances. A coating for desensitizing the outer surface layer of a main explosive charge is also disclosed.

Abstract: The disclosure relates to a propellant charge for cannons comprising bundles (11) of tightly held tubular propellant sticks which are provided with connections between the propellant sticks' outer surfaces and their combustion channels, these connections consisting of either longitudinal slits or of uniformly spaced, weakened points in the form of perforations, slits, open notches or bored holes which extend from the outer surfaces of the propellant sticks to the combustions channels, the bundles (11) being surrounded by disoriented powder flakes, powder grains or short powder rods or tubes (9), these filling the remaining portion of the combustion space (7).The disclosure also relates to a method of producing such a charge.

Abstract: Structure for generating nitrogen gas for inflating an air bag vehicle occupant restraint comprises a grain made of an azide based material which generates gas upon combustion. The grain has an ignition enhancing coating thereon consisting essentially of 20 to 50% by weight of an alkali metal azide, 25 to 35% by weight of an inorganic oxidizer, 10 to 15% by weight of a fluoroelastomer binder, 15 to 25% by weight of magnesium, and 1 to 3% by weight of fumed silicon dioxide. The coating may also include 1 to 6% by weight of graphite as a roughening agent.

Abstract: A propellant charge and method of manufacture thereof by which the increase in maximum gas pressure within the upper use temperature range which occurs upon firing can be influenced until eliminated. The propellant charge is manufactured by compacting a first portion of the propellant charge which corresponds to between 50-80% of the total mass of the propellant charge, and then adding the balance of the propellant charge as loose powder on top of the first portion.

Abstract: Propellant charge, the combustion of which takes place according to at least two thrust modes, and which makes it possible to obtain at least one acceleration phase and one cruising phase of the self-propelled device equipped with this charge.The propellant charge is of the so-called "trumpet block" type with radial combustion from a central channel which has a star-shaped cross-section over a length equal to at least one third of the total length of this charge. In order to obtain at least one dual combustion mode using only a single charge of propellant, that part of the channel which is of star-shaped cross-section possesses at least one zone in which the star of the channel has at least four arms which determine at least two tooth-like sectors of propellant with a large sector angle (A) and at least two tooth-like sectors of propellant with a small sector angle (a), distributed symmetrically relative to the axis of the charge.

Abstract: A stacked load of gas-forming pyrotechnic fuel pellets comprising metal, metal oxide and PTFE in varying amounts for use in apparatus for severing conduits in high pressure environments.

Abstract: An integrated jet perforation and controlled propellant fracture device and method for enhancing production in oil or gas wells, wherein the device is inserted in a well bore to the level of a geological production structure; the fracturing device being constructed with a cylindrical housing of variable cross-section and wall-thickness with the housing filled with combustible propellant gas generating materials surrounding specially oriented and spaced shaped charges, having an abrasive material distributed within the propellant filled volume along the device length to produce enhanced perforations with attendant pressure-controlled gas and fluid injection into the perforations to produce controlled frac entry at point or points desired in the producing zones of the well bore, wherein a high velocity jet penetrates the production zone of the well bore initiating fractures, and is simultaneously followed by a high pressure propellant material which amplifies and propagates the jet initiated fractures.

Abstract: A method of producing pressed rocket propellant with good flash suppression and a high burning velocity, i.e. containing optimal quantities of flash reducing agent and catalysts. The meethod is characterized by the entire quantity of flash reducing agent required in order to achieve the result desired being mixed into a separate quantity of propellant while the entire quantity of catalysts required in order to achieve the result desired is mixed into the remaining quantity of propellant, after which these propellants containing either flash reducing agent or catalysts are converted into an appropriate form and mixed in layers or in its entirety and thereafter pressed into the form desired. In the body of propellant obtained, the flash reducing agent and catalysts will be separated, and will not interfere with each other's function.

Abstract: A smoke grenade for providing screening. A container has in the lower portion thereof a discharge composition ignited by a primer composition for igniting an ignition/bursting composition which in turn ignites a set of easily ignitable smoke charges, preferably disc shaped smoke charges surrounding the ignition/bursting composition. Ahead of the first charges in the direction of travel of the grenade is a further smoke charge which is compact and hence more slowly ignitable than the first set of charges. A delay booster and a further primer composition ignite this further smoke charge after a delay.

Abstract: An explosive booster is provided for the detonation of insensitive blasting agents. The booster contains TNT as the sole explosive ingredient, is sensitive to blasting cap initiation yet remains insensitive to impact initiation. The booster comprises an elongate structure having a gradually increasing density from end to end, only the less dense end being cap sensitive. Reduced density is accomplished by the incorporation of voids or pockets, by means of, for example, glass microspheres. Particulate sodium nitrate and vermiculite are included as density enhancers.