GB2606722A - Improved explosive charge device and assembly - Google Patents

Abstract

An explosive charge device includes a housing 14, adapted to receive a removable explosive cartridge 43, and further adapted to locate on, at, in, or adjacent to a firing end of the said housing, an incendiary component 44 comprising incendiary material. The device or an assembly is configured such that firing of the explosive cartridge 43 in the device or assembly causes explosively formed penetrator to be formed, which subsequently impinges on the incendiary component 44 such that it is clad with a layer of said incendiary material. The device may be used for explosive ordnance disposal.

Description

IMPROVED EXPLOSIVE CHARGE DEVICE AND ASSEMBLY

Field of the Invention

The invention relates generally to an explosive charge device and assembly, used for example to contain an explosive charge such as within a removable cartridge. The invention has particular but not exclusive application in explosive ordnance disposal (EOD), and deflagration, particularly in a marine environment.

Examples may be used in the rapid deployment and safe storage of explosive material.

Examples of the invention are suitable for use with shaped charges and systems and assemblies using shaped explosive charges, generally referred to in the art as "shaped charges".

Background

Explosive devices are known which are designed to direct an explosive force towards a target. This direction is referred to herein as the "firing direction" and references to "forward" and "rearward" are terms used relative to the firing direction. The term "rearward" can be interpreted also by the term "distal" or "distally" and the use of such wording in the spec should be interpreted as such. The rear of an explosive device as described herein is that part of the device which is distal from the target in use. In such devices a volume of explosive is contained, for example in a charge chamber or cartridge.

Prior Art

UK Patent Application GB 2533822 (ECS Special Projects limited) describes an explosive charge assembly comprising cartridge containing explosive and housing, and illustrates examples which provide for the Monroe effect. The Monroe effect is well known and relates to enhancing the effectiveness of high explosives by the introduction of a cavity in the forward face of the explosive. In the case of plastic explosive this can be done by moulding the surface of the plastic material for example. A volume of explosive shaped to make use of the Monroe effect is commonly referred to as a "shaped charge".

The shaping of a shaped charge has been found to assist in focussing energy in a desired, e.g. forward, direction. In an explosive device using a shaped charge, the charge may be retained in a charge chamber, which may comprise for example a cylinder open at both ends. It has been found that the effectiveness of a shaped charge may be further enhanced by the introduction of a liner to support and control the form of the cavity. The liner may in effect form the forward end wall of the charge chamber.

Various geometric forms for the liner have been employed. Usually these are radially symmetric bodies with hemi-spherical, conical, hyperbolic or other shapes of concavity or recess at acute or obtuse included angles, which may be pressed into the forward face of the explosive. Non radially-symmetric shapes have also been the subject of experimentation including wedge and toroidal shapes The term concave should be interpreted as to include all such shapes.

So in other words, these concavities are generally maintained in the high explosive by a preformed shape known as a "liner" and may be formed in a variety of materials and used for various target effects. It is well known that a cone with an acute internal angle will produce a hypersonic jet of plasma energy followed by a slower "slug" which follows in the jet stream. Such liners are extensively used when a high order detonation or surgical penetration is required.

It is further well known that a hyperbolic or spherical with a shallow obtuse internal angle does not produce a hypersonic jet stream but inverts the liner into a bullet shaped penetrator, referred to also a san explosively formed penetrator. This effect is known within the art as the Misznay-Shardin effect and such penetrators are particularly effective when breeching the outer case of a target is required, particularly when a larger entry hole is required to be created in a target when the explosive is fired, such as when flooding of the control section of a sea-mine. The bullet shaped penetrator or explosively formed penetrator (EFP) is thus a self-forging 'warhead.

An explosive device may be provided with some means to provide a "standoff, the term commonly used to denote the distance between the forward face of the charge or liner and the target. Such means may abut the target prior to detonation.

In devices using shaped and other kinds of charges, the charge may comprise a so-called "insensitive" explosive material that is relatively stable such as a modern plastics explosive. If a flame is applied to a typical plastic explosive, it will ignite but not explode. In order to make it explode, some means of high-energy initiation such as a detonator or "booster" charge of more sensitive explosive material is usually required.

This means of initiation may be remotely operable, for example using a tube filled with explosive material, or a wired or wireless electrical connection.

A booster charge which may be provided in a detonator is sometimes known as a "primary" explosive. It is standard practice for the two elements (e.g. the plastic explosive and the detonator) to be kept separate until the last conceivable moment and for the detonator to be removed if the operation is cancelled. Without the detonator fitted to a shaped charge device the two components may be transported provided that special precautions are taken. A device with the detonator fitted has to be treated as effectively a live bomb.

Whilst the initial use for this effect has been for military purposes, for example in armour piercing warheads, more recently it has been found that shaped charges are particularly useful in the commercial Explosive Ordnance Disposal (EOD) field for seabed historic ordnance clearance for purposes such as wind farm construction and generally for subsea cutting and drilling of the seabed for oil well construction. Broadly, in the area of EOD, such devices are used to either demolish e.g. high order (e.g. explode) a target or to neutralise the target either by flooding or to attempt to ignite the insensitive explode core thereby inducing a deflagration without a high order detonation. Increasingly, due to the adverse effects on the undersea environment and its effect upon marine life of high order detonations of large volumes of explosives in the aquatic environments, it is becoming desirable to induce a deflagration (known as a Low Order) of the target explosive material.

By experimentation and in use, it has been discovered that a number of key factors affect the overall performance of a shaped charge, including the three dimensional axial precision of the liner with respect to the charge chamber in which the explosive material is retained, the material used for the liner, the thickness of the liner, the shape of the cavity (usually as determined by the liner), the rigidity of the charge chamber, the amount of standoff and the volume of the explosive charge. It will be appreciated that some applications for explosive devices require more accuracy and/or higher performance than others.

Transporting explosive devices, particularly across national borders, is controlled by strict regulatory and security requirements. It has therefore been the trend, particularly but not exclusively in the field of commercial EOD, to move towards "self-fill" devices that are supplied devoid of explosive and either have the liner held at a particular position or with the liner provided loose as a disc with a concavity. As this concept affords a completely inert device it can be transported with little regulatory control and minimal safety precautions.

However, in use, it has been found that the packing of such "self-fill" devices with explosives is a skilful operation that must be undertaken with care as voids in the explosive may adversely affect the performance of the device. Also, as it is usually difficult to undertake this operation in a small craft that is normally used for commercial marine EOD, this operation is usually undertaken on a support vessel.

Should the operation be cancelled, due to inclement weather for instance, it is a 25 painstaking task to remove the explosive from a shaped charge device so that it may be stored safely only to have to re-pack it if the mission is resumed.

Examples of shaped charge devices are disclosed in EP-B1-1476712 (Sidney ALFORD) and US 2012/0247358 (Thomas BERGER) When a shaped charge device, for example in the form of a demolition tool, disruption device or a disarmer is intended to be used subsea, the standoff must be maintained in the form of an hermetically sealed air filled enclosure and when deflagration is required it is important to create as large entry hole in the target (such as a sea-mine) as possible whilst avoiding the use of a high-energy hypersonic jet.

Thus a typically used shaped for the shaped charge is preferably a shallow aluminium parabola or cone with a large internal angle; this produces an entry hole approximately 1/3 of the charge case diameter.

Generally magnesium liners are used when deflagration is required with the intention of inducing an incendiary effect; the use of magnesium liners has limited success as either the magnesium tends to be consumed in the initial explosion of the disarming tool or, in the case of an EFP it is less effective at penetrating the target (e.g. sea mine) casing.

It is an object of the invention to provide an improved device/assembly which has a better at deflagration of targets such as mines.

Summary of the Invention

According to a first aspect of the invention there is provided an explosive charge device including a housing, adapted to receive a removable explosive cartridge, and further adapted to locate, substantially spaced from the firing end of said cartridge when fitted, an incendiary component comprising incendiary material.

The device may be adapted to locate said incendiary component on, at, in, or adjacent to a firing end of the said housing.

Said housing may include a stand-off housing portion, adapted to space the removable explosive cartridge when inserted into the housing, from the firing end of the device, along the longitudinal axis of the device.

The firing end of the housing may include a sleeve portion, adapted for locating or receiving the incendiary component.

The sleeve portion may be formed as a cylindrical wall.

The cylindrical wall may be formed in the firing end of the stand-off housing.

The device may have means to locate a cap on the firing end of said housing, adapted 5 such that it provides space for an incendiary component to be located between the firing end of the housing and the cap when fitted.

Located within said sleeve portion or on the interior surface of said cap, may be one or more projections or recesses to locate said incendiary component.

In a further aspect is provided an assembly including an incendiary component located on, at, in, or adjacent to the firing end of the housing, or located between the firing end of the housing and the cap.

Said incendiary component may be generally disc shaped.

Said incendiary component may include one or more recesses or projections which is/are adapted to engage with the corresponding projections or recesses in the cap or sleeve portion.

Said housing may include a cylindrical recess generally located at the distal end thereof, adapted to receive/locate said removable explosive cartridge.

Said housing may comprise a detonator housing at the distal end, connected or connectable to a stand-off housing at the firing end, the detonator and standoff housings formed from two separate components.

The housing or detonator housing may include said cylindrical recess, defined by a cylindrical wall, said recess being open ended at the firing end.

The distal end of the housing or detonator housing may include a base, and said base including means to attach insert or fix a detonator thereto.

The device or assembly may include means to receive, or including, a cylindrical cartridge housing, within said cylindrical recess, said cartridge housing adapted to locate or receive an explosive cartridge.

The assembly or device may include an explosive cartridge contained within said housing and/or within said cartridge housing.

The assembly may include an end wall or liner located at the firing end of said explosive cartridge, having a recess.

Said explosive cartridge may be in the form of a hollow cylinder, having an integral end wall at the firing end, said end wall being concave, so as to form said recess.

Said incendiary component is preferably substantially spaced from said liner or cartridge end wall.

Said base of the housing or detonator housing, and/r the distal end of the cartridge, may an orifice or bore to receive or locate a detonator and/or including means to attach insert or fix a detonator thereto.

Said incendiary component cornprises preferably substantially magnesium.

The device or assembly is configured such that firing of the explosive cartridge in the device or assembly causes an explosively formed penetrator to be formed, which subsequently impinges on the incendiary component such that it is clad with a layer of said incendiary material.

Brief Description of Drawings

The invention will now be described by way of examples and with reference to the following drawings: Figure 1 is a longitudinal cross section of one example showing a deflagration disarming explosive charge assembly fitted with a detonator; Figure 2 is longitudinal cross-section of the cartridge assembly of Figure 1 shown fitted with a transportable removable plastic transit cap; Figure 3 is a longitudinal cross-section illustration of one example of the invention of the 5 assembly in position against a mine target moments after detonation showing the formation of the EFP consequent and subsequent to firing of the explosive charge device/assembly; Figure 4 is a part cross sectional illustration of consequently formed EFP welding itself to the incendiary medium; and Figure 5 is a part cross sectional illustration of the EFP with the incendiary medium welded to the EFP embedded into the target explosive core.

Detailed Description of the Invention

In a general example, e.g. the explosive charge device/assembly includes an incendiary component located substantially spaced from said cartridge when fitted, e.g. substantially spaced from said, liner or end wall, preferably at the firing end of the device/assembly, and in any case configured such that on firing the explosive charge which is preferably a shaped charge, (e.g. formed as an explosive cartridge), an explosively formed penetrator is subsequently formed via the Misznay-Shardin effect, which impinges on the incendiary component such that it is provided further with an incendiary cladding, i.e. clad with, an incendiary metal, preferably magnesium. This then welds against target casing, for example of another metal, which then assists improved deflagration.

The inventors have made use of the fact explosive welding uses explosives to weld dissimilar metals such as aluminium and magnesium; furthermore this process can be conducted under water, i.e. submerged in water.

So in other words, immediately following initiation, i.e. firing of the explosive charge device, the liner or firing end /face of the cartridge, which is preferably indented, (i.e. concave) becomes inverted and an EFP is forged by the explosion which is constrained to direct the energy, and also causing the EFP to hit, i.e. to impinge on the incendiary component, so as to clad itself with the incendiary material before friction causes it to be ignited as it penetrates the target (e.g. mine) casing and embeds itself in the target explosive material causing it to be consumed in a low order deflagration.

Referring to figure 1, this shows a cross section of a shaped charge deflagration cartridge device/assembly according to one example. The illustrated assembly is generally cylindrical receptacle having four main parts, including a cylindrical cap 46 preferably formed from a polymer material Figure 1 shows an axis which can be referred as the central longitudinal axis.

The cap closes (i.e. caps /seals) a cylindrical cavity 47 formed in a standoff housing 8. The standoff housing, used to provide the requisite distance of the end of the explosive charge to the target, may also be fabricated preferably from a polymer material. In the forward (target) end of the housing 8 is formed an elongated cylinder cavity portion 47 formed from cylindrical walls 48 at the forward end of the assembly/device separating the cavity 47 from the encapsulated air gap 35. Thus there is an end wall 100 at the target end of the standoff housing. Contained in the cavity 47 is sealed a (preferably magnesium) incendiary medium component 44. Thus the cavity is adapted to retain and locate the incendiary component. This may be provided as e.g. a solid disc having preferably a cylindrical aperture 45.

Alternatively the incendiary medium component may comprise a flat coil of ribbon material coiled such that it forms a disc with a cylindrical aperture 45, located preferably centrally. The cavity and/or cap may have one or more projections or recesses such as central spindle or peripheral fins or slots, adapted to mate or co-operate with corresponding recesses and /or projections on the incendiary component to help locate it.

Moving rearwards, i.e. distally, a detonator housing 14 is provided, preferably formed from a polymer material. The detonator housing generally is in the form to provide a cylindrical cavity, open ended on the forward sides to receive the explosive cartridge and optionally a cylindrical cartridge enclosure component 43. It is preferably provided with an attachment means, such as a screw thread, so it can be attached and detached from the standoff housing. At its rearward end the housing 14 has a circular base wall 37, the rearward end face of the cartridge/cartridge enclosure component generally abutting against component base wall 37 So in other words detonator housing 14 is formed having cylindrical wall (providing an cylinder open ended on the forward side) the (forward) ends of which abuts against the standoff housing 8, thus forming a housing or cover to generally encapsulate a cartridge enclosure 43. In the distal (rearward portion) i.e. the base of component 14 is base is provided an (elongated) cylindrical aperture which allows placement and accurate positioning of a detonator, the detonator being secured by means of a detonator retaining nut 6; in other words to facilitate the detonator 9 to be retained in position. A strain relief locknut 19 may also be provided at the rearward end of detonator housing 14 to provide a means to apply tension to communication cables to avoid tension on the detonator connection, so as to avoid pulling the detonator out of position.

Shown contained within the conjoined detonator housing and standoff housing is an elongated cylindrical cartridge enclosure component 43 being constructed from e.g. alloy steel to provide additional strength by way of hoop stress in the milliseconds after 20 detonation to cause the energy from detonation to be projected forwards.

Referring to Figure 2, the cartridge enclosure 43 circumscribes the removable cartridge 1 (when the cartridge is inserted) and thus forms a charge chamber.

Referring to Figure 3, the generally cylindrical cartridge 1 in one example is formed from a generally cylindrical side wall 21 and an end wall 22 on the forward /target end (which is thus disc shaped), both defining a charge chamber 3. The cartridge shown in the examples thus has one open or at least partially open end, at the distal (ie rearward) end.

Reference numeral 23 indicates an end face of the open ended cartridge cylinder. The open end of the cylinder may be closed by a removable cap 4. Other forms of closure may be provided. The closure may be removable and/or disposable but this is not essential. Cartridges according to examples may be provided with a sealed membrane that is ruptured but not necessarily removed prior to use.

The proximal i.e. forward end wall 22 according to examples preferably has a concave 5 shape 2; and further may also be used additionally to form a concave depression in the forward surface of explosive material 15 contained in the cartridge 1 (thus producing a shaped charge in addition.

In the illustrated embodiment this depression is shown as a conical cavity or "concavity" 2. Other shapes are possible. The cavity or other depression 2 may be spun, machined or otherwise formed in the end of the shaped charge cartridge 1. Thus the end wall 22 may be integrally formed with the sidewall 21. The side and circular end wall 21, 22 may be manufactured from metal such as but not limited to aluminium. This manufacturing may be undertaken to precise tolerances encapsulating the geometric shape required to maintain the optimum performance of the device.

According to examples described the thickness of the walls 21 or 22 or both may be closely maintained to precise tolerances 2% of the diameter of the charge chamber 1 (Fig 2). The removable cap 4 may be used to close the charge chamber 3, for example for transportation when the cartridge is filled with explosive material, indicated by reference numeral 15. The cap 4 may be made of plastic material and may be disposable.

Many other shapes are possible for the depression or concavity 2 for differing applications. Such shapes include but are not limited to hemi-spherical, shallow cone, shallow parabola, wedge "V" shape, conical and bell shape. Whilst it has been found that aluminium is suitable due to results of tests and general range of desired effect, the shaped charge cartridge 1 may also be manufactured from other materials to achieve different applications. Such materials include but are not limited to aluminium, polymer, glass, molybdenum, and magnesium.

The circular end wall 22 of the cartridge 1 may take therefore the place of the "liners" currently used in shaped charge devices. In other words, according to embodiments of the invention the cartridge may be considered to comprise a charge chamber with an integral liner. Alternatively, the whole side and end walls 21 and 22 may together be considered as forming a "liner". It will be seen from Figure 2 that the illustrated cartridge has an "M" shaped cross section. It will be appreciated by those skilled in the art that the wall 22 forms the front of the cartridge in the firing direction. In other words, the firing direction is generally parallel to the axis of the cylindrical wall 21 in the direction from the open end towards the wall 22.

In other embodiments the wall 22 may be separate from the cartridge and effectively provided by a separate liner; this is located at, adjacent to or over the end of the cartridge. The portion of the liner at the forward end or forward of the cartridge is thus again preferably indented i.e. to form a concave surface.

The concave surface of the end wall / liner 22 ensures on firing of the cartridge, it is inverted to become an effective projectile shape moving rapidly forward; i.e. a high velocity explosively formed penetrator due to the Misznay-Shardin effect.

Referring to Figure 3 this illustration shows the explosively formed penetrator 49 being formed moments after detonation. Figure shows the whole device attached to or abutting against a target, e.g. a mine having wall/casing 51.

The cartridge enclosure 43, ensures that the energy of the explosion of the explosive charge 15 in the cartridge, is directed forward thus causing the end wall 22 of the cartridge to be inverted into the classic winged bullet shape of the penetrator 49 and move towards the forward end of the device and the target.

Referring to Figure 4 this part section of the forward portion of the invention shows the fully formed EFP 49 forcing its way through the distal i.e. rearward end of the aperture 45 in the incendiary medium/component 44 SG) which as described may comprise a disc with central aperture 45 44. This causes the medium 44 &G to be explosively welded to the outer surface of the EFP4 and form a cladding of incendiary medium 50 and provide a subsequent degree of penetration of the target (e.g. mine outer casing 51) Referring to Figure 5 this part section shows the forward portion and the fully formed EFP 49 comprising the initially formed EFP formed from the end wall 22 with the cladding of incendiary medium 50 from the incendiary component 44 welded thereon i.e. the incendiary medium cladding the outer surface of the EFP.

Friction resulting from the penetration of fully formed EFP 49 (replete with incendiary medium) with the mine case 51 causes the incendiary cladding to ignite and is embed into the core explosive content 52 of the target munition causing deflagration.

Examples of the present invention provide explosive charge device, including a removable cartridge that may combine the liner, e.g. a wall defining a forward face in the charging direction, with the charge chamber, e.g. a sidewall such as a cylinder whose axis is parallel to the firing direction for containing the explosive material. The liner may be pre-formed with a cavity to form a shaped charge (e.g. where the forward face of the cartridge or liner is concave) or where a dissimilar material between the cylinder of the charge chamber and the liner is desirable then such liner may be retained into position by spinning the case material to retain the liner.

Significantly it has been found in tests that integral forming of the cartridge comprising end wall and at least one sidewall, improves the axial accuracy of the cavity to the charge chamber, e.g. the alignment of the centre of symmetry of the liner with the axis of the cylinder. This reduces the possibility of the liner being fitted out of square or off centre and causing an inefficient detonation. The extension of the liner or front wall which retains the explosive charge in the rearward direction assists in focusing the explosive force in the forward direction and may be useful with charges having flat or protuberant forward surfaces as well as with shaped charges of the kind described herein.

The cartridge may be housed in a cylindrical cartridge enclosure, which extends rearwardly from the standoff housing and may be integral to the standoff housing, such cartridge housing is preferably of an alloy steel material to constrain the initial spread of explosive force and direct its effect in a forwardly direction Examples may also provide an explosive charge assembly comprising a cartridge, charge chamber, standoff housing and a cartridge housing, the cartridge having an end wall defining a forward face in a firing direction and at least one side wall, the forward and side walls defining a charge chamber for receiving explosive material, and the housing being configured to, at least partially enclose the cartridge, whilst conveniently fitting into the cartridge enclosure.

The rearwardly, generally cylindrically formed section being the detonator housing has a rearward wall through which the detonators is inserted and retained using a clamping nut These housings may be manufactured from a polymer or other material to reduce fragmentation and the possibility of galvanic effect when dissimilar metals are deployed in a saline environment. Fragmentation may be problematic, especially in air environments, as it produces shrapnel that is potentially dangerous to people in the vicinity. Therefore depending on the intended use of a device or assembly according to embodiments of the invention it may be desirable to use a material that is not prone to fragmentation. Such materials are well known in the art.

The end wall of the cartridge may have a concave or other indented shape and thereby serve the function of a shaped liner in shaping the front face of the contained explosive.

Optionally the forward end of the standoff housing shall contain a suitable cavity into which material that may be required to be explosively welded to the penetrator can be conveniently located An assembly according to the examples described enables the cartridges to be pre-filled on shore or on the support craft or even factory pre-filled. These could be easily fitted into the housings immediately prior to use even on a small support craft thereby improving safety. Should the operation need to be abandoned for whatever reason the cartridge containing the explosive material can be easily and quickly removed from the housing and made safe.

It should be noted that in an assembled explosive device according to examples, the cartridge contains only explosive material and does not contain a bullet or other projectile for example.

An assembly according to the examples described, may include means defining a standoff, where some separation between the charge and the target is desired. For example for underwater use, such means may define a closed volume of air. According to other examples the standoff may simply comprise a spacer.

When it is a requirement to vary the amount of explosive for a particular application a variant of assembly according to examples includes the ability to adjust the charge chamber volume. This may be achieved for example using a moveable end wall for the charge chamber, which may be provided as part of a detonator carriage or charge former.

Previously variations in the charge chamber volume have been achieved by the introduction of spacers in front of the liner. This has the disadvantage of increasing the standoff length and thereby affecting the focus and thus the efficiency of the device.

Examples may enable the reduction of the enclosed volume of the charge chamber from the rear, for example by the employment of a moveable detonator carriage which may be moved in the firing direction using a screw thread, to allow for infinite or continuous rather than stepwise fine adjustment of the charge volume.

This adjustability of the size of the charge chamber may be provided in assemblies that do not use cartridge with integral liner. Thus, examples provide an explosive charge assembly comprising a housing at least partially enclosing a charge chamber for receiving explosive material, and a forward end wall at least partially defining the charge chamber, in which the housing comprises a movable rear end wall for the charge chamber, the position of the end wall being variable along the firing direction to vary the volume of the charge chamber. Thus, the forward end wall may comprise the liner, for example shaping the forward face of the charge.

It will be appreciated that variations may be made to the embodiments described 30 without departing from the scope of the invention as defined by the claims.

Claims (23)

1. Claims 1. An explosive charge device including a housing, adapted to receive a removable explosive cartridge, and further adapted to locate, substantially spaced from the firing end of said cartridge when fitted, an incendiary component comprising incendiary material.
2. 2. A device as claimed in claim 1 adapted to locate said incendiary component on, at, in, or adjacent to a firing end of the said housing.
3. 3. A device as claimed in claim 1 or 2 wherein said housing includes a stand-off housing portion, adapted to space the removable explosive cartridge when inserted into the housing, from the firing end of the device, along the longitudinal axis of the device.
4. 4. A device as claimed in any of claims 1 to 3 wherein the firing end of the housing includes a sleeve portion, adapted for locating or receiving the incendiary component.
5. 5. A device as claimed in claim 4 wherein the sleeve portion is formed as a cylindrical wall.
6. 6. A device as claimed in any of claims 1 to 5 wherein said cylindrical wall is formed in the firing end of the stand-off housing.
7. 7. A device as claimed any of claims 1 to 6 including means to locate a cap on the firing end of said housing, adapted such that it provides space for an incendiary component to be located between the firing end of the housing and the cap when fitted.
8. 8. A device or assembly as claimed in any of claims 4 to 7 wherein located within said sleeve portion or on the interior surface of said cap, are one or more projections or recesses to locate said incendiary component.
9. 9. An assembly as claimed in any preceding claim including an incendiary component located on, at, in, or adjacent to the firing end of the housing, or located between the firing end of the housing and the cap.
10. 10. An assembly as claimed in claim 9 wherein said incendiary component is generally disc shaped.
11. 11. An assembly as claimed in any of claims 8 to 10 wherein said incendiary component includes one or more recesses or projections adapted to engage with the corresponding projections or recesses in the cap or sleeve portion.
12. 12. A device or assembly as claimed in any preceding claim wherein said housing includes a cylindrical recess generally located at the distal end thereof, adapted to receive/locate said removable explosive cartridge.
13. 13. A device or assembly as claimed in any of claims 1 to 12 where said housing comprises a detonator housing at the distal end, connected or connectable to a standoff housing at the firing end, the detonator and standoff housings formed from two separate components.
14. 14. A device or assembly as claimed in any of claims 11 to 13 wherein the housing or detonator housing includes said cylindrical recess, defined by a cylindrical wall, said recess being open ended at the firing end.
15. 15. A device or assembly as claimed in any of claims 1 to 14 where the distal end of the housing or detonator housing including a base, and said base including means to attach insert or fix a detonator thereto.
16. 16. A device or assembly as claimed on any of claims 11 to 15 including mean to receive, or including, a cylindrical cartridge housing, within said cylindrical recess, said cartridge housing adapted to locate or receive an explosive cartridge.
17. 17. An assembly comprising an assembly or device as claimed in any preceding claim, including an explosive cartridge contained within said housing and/or within said cartridge housing.
18. 18. An assembly as claimed in claim 17 including an end wall or liner located at the firing end of said explosive cartridge, having a recess, for example which is concave.
19. 19. An assembly as claimed in claim 18 wherein said explosive cartridge is in the form of a hollow cylinder, having an integral end wall at the firing end, said end wall being concave, so as to form said recess.
20. 20. An assembly as claimed in claim 17 to 19 wherein said incendiary component is substantially spaced from said liner or cartridge end wall.
21. 21. A device or assembly as claimed in 14 to 20 wherein said base of the housing or detonator housing, and/or the distal end of the cartridge, includes an orifice or bore to receive or locate a detonator and/or including means to attach insert or fix a detonator thereto.
22. 22. A device or assembly as claimed in any preceding claim wherein said incendiary component comprises substantially magnesium.
23. 23. A device or assembly as claimed any preceding claim, configured such that firing of the explosive cartridge in the device or assembly causes an explosively formed 25 penetrator to be formed, which subsequently impinges on the incendiary component such that it is clad with a layer of said incendiary material.