EP0404853A1

EP0404853A1 - Process for manufacturing explosive charges from non-pourable mixtures.

Info

Publication number: EP0404853A1
Application number: EP19890907738
Authority: EP
Inventors: Manfred Luebben; Benjamin Furch; Horst Pinkernelle
Original assignee: Rheinmetall GmbH
Current assignee: Rheinmetall Industrie AG
Priority date: 1988-11-10
Filing date: 1989-07-13
Publication date: 1991-01-02
Anticipated expiration: 2009-07-13
Also published as: EP0404853B1; WO1990005124A1; DE3838084A1; DE58905329D1; PT92288B; GR890100474A; PT92288A

Abstract

Procédé de fabrication de charges explosives à fort pouvoir détonant à partir de mélanges non coulants. On utilise à cette fin un mélange de matière explosive comportant 85 à 92,5% d'un explosif puissant (HMX, RDX, TRTB etc.) en tant que constituant solide et 7,5 à 15% d'un constituant fusible (TNT, TNB, TNCB). Ce mélange est porté à une température de traitement proche du point de fusion du constituant fusible. On verse ensuite le mélange de matière explosive tempéré et bien mélangé dans un dispositif de compression chauffé et on forme la charge selon le procédé de moulage sous pression.Process for manufacturing explosive charges with high detonating power from non-flowing mixtures. For this purpose, a mixture of explosive material is used comprising 85 to 92.5% of a powerful explosive (HMX, RDX, TRTB etc.) as a solid component and 7.5 to 15% of a fusible component (TNT , TNB, TNCB). This mixture is brought to a treatment temperature close to the melting point of the fusible component. The well-mixed, tempered explosive mixture is then poured into a heated compression device and the charge formed by the die-casting process.

Description

Process for the production of explosive charges from non-pourable mixtures

The invention relates to a method according to the preamble of patent claim 1.

It is already known to produce explosive charges by casting or pressing, customary casting processes generally lead to an inhomogeneous composition of the explosive charge as a result of sedimentation processes. The mechanical post-processing that is always required results in comparatively high production costs; after all, losses of explosives due to the lost head must be expected.

Known pressing methods result in a relatively low density of the explosive charge, which excludes the maximum achievable performance. In order to increase the mechanical stability of the explosive charge, it is still necessary in the case of pressing processes to add a certain percentage of inert substances, which also reduces the output.

From DE-PS 21 31 282 is the combination of a casting and printing process for the production of explosive

Charges known that avoids the two disadvantages mentioned above. So far, however, this method has only been used for pourable explosive mixtures. The invention has for its object to provide a method for producing explosive charges of high explosive power from non-pourable explosive mixtures.

This object is achieved by the features of the characterizing part of claim 1.

Advantageous refinements for carrying out the method emerge from the subclaims.

In terms of explosive power and charge density, the charges produced according to the invention are technically at the upper limit of performance

producible explosives. The cargo owes this performance to the high proportion of highly explosive HE explosives (HMX, BDX, PETN). In order to use die casting technology, the load must contain at least 7.5% TNT, TNB or TNCB. In addition, the load to reduce the vulnerability must contain care-enhancing additives in order to guarantee safe processing and the load property against

to be able to improve external influences of a dangerous nature. This nurturing property shows

for example TNT. An addition of about 7.5%

sets the sensitivity of the load

down. A plastic content of 0.5 to 2.5%, for example, improves the nourishing properties, since it surpasses the TNT's workability. This plastic content in particular reduces the sensitivity to shock and sensitivity to shards. The invention is explained in more detail below with reference to the drawing.

It shows:

1: the process sequence on the basis of a block diagram;

Fig. 2a:

and 2b: the redeployment of the highly explosive (HE-)

Fes tkorns

The commercially available explosive mixture used as the starting substance, the z. B. consists of 90% HMX as a solid component and 10% TNT as a fusible component, is first in a heatable mixer to the processing temperature of about 80 ° C

brought (block 1 in Fig. 1). Since the mass has a very poor thermal conductivity, water is added to improve the heat transfer and thus to shorten the heating-up time, thereby simultaneously passivating or phlegmatizing the explosive mixture. In this processing phase - if necessary - additives such as. B. nitroguanidine or plasticizing plastic granules as a binder or phlegmatizing and plasticizing agent can be added.

The water that is no longer required for the further processing stages easily escapes again in a short time (block 2), so that the temperature-controlled and uniformly mixed explosive mixture is then poured into a heated press tool (block 3), evacuated and placed under such a high pressure that the Meltable component instantaneously solidifies (block 4). After cooling below the solidification point, the explosive body can then be removed from the mold. In other embodiments have been considered fixed

Components instead of HMX Hexogen (RDX) and instead of TNT

TNB or TNCB used, with the weight ratios: RDX / TNT: 85/12; 90/10; 92.5 / 7.5,

RDX / TNCB: 90/10.

If the detonation speed is selected as a measure of the performance, particularly high values for RDX / TNT: 90/10 (detonation speed: 8620 m / s) and 92.5 / 7.5 (detonation speed: 8660 m / s) ) reached.

In a further embodiment of the process according to the invention, the explosive mixture is heated just below the melting point of the meltable component, so that the mixture remains free-flowing.

This procedure has the advantage that the free-flowing explosive mixture can be metered very easily, so that it can be reproduced in a simple manner

Have load weights (great shape accuracy and dimensional stability) produced. The further heating necessary for pressing then takes place in the heated pressing tool itself.

It has proven to be particularly advantageous if the individual HE explosive grains are first coated directly with the thermoplastic binder and only then is the fusible component (e.g. TNT) added.

The layering of the HE grains with the binder can be carried out, for example, using the so-called slurry process. For this purpose, an aqueous suspension of the HE particles is prepared by vigorous stirring. A polymer solution is metered into this suspension. The polymers are coated by affinity forces for the solid particles. The solvent is then stripped off by dilution. For this purpose, the entire suspension (slurry) has to

> 80ºC. After removal of the solvent and thus completion of the grain coating operation, the suspension is filtered and the residue is dried in vacuo at temperatures of 40 ° C. Particles of any grain size can be coated. A corresponding grain is shown in Fig. 2a. The grain of the solid explosive component e is denoted by 5 and the shell of the thermoplastic binder (polymer) by 6.

In a practical example, 1 was

HMX explosive granules suspended in distilled water with stirring. This suspension was called

Polymer solution fed a thermoplastic polyurethane elastomer, solverted in cyclohexanone. The

Solvent content can be kept low since a sufficiently good solvation is achieved quickly. After evaporation of the solvent, the

Filtration and drying resulted in an explosive granulate which was evenly coated with polyurethane.

In a further exemplary embodiment 1, the HE particles were first coated with TNT in an upstream process step. For this purpose, a suspension of the HE particles in water was created. The TNT amount of 1 to 2% based on the explosive is dissolved in a solvent. The solvent should not or only slightly dissolve the solid explosive particles. This TNT solution is added to the suspension and the solvent removed again by heating the slurry to 80 ° C and distilling. The TNT covers it

Solid grain. The coated material is then cooled and filtered. This pretreated, TNT-coated explosive material is then - as described above - further treated and provided with a binder layer. A corresponding layer structure of such particles is shown in Fig. 2b. The HE grain is denoted by 5, the TNT coating by 7 and the binder layer by 8.

The particular advantage of the particle structure shown in Fig. 2b is that the TNT explosive component is initially liquefied by the processing temperature. Due to its ease of movement, all cracks, gaps, holes etc. on the solid HE explosive are completely filled with material. This effect is desirable because an explosive charge structure that is as compact as possible makes a decisive contribution to reducing the sensitivity to dangerous external influences.

Finally, it is also conceivable to carry out a so-called mixed coating of TNT and polymer around the HE grain.

For this purpose, a joint processing of TNT and

Made polymer solution. Processing takes place by preparing the polymer solution in which the desired TNT content (1 to 2%) is introduced and dissolved. The further procedure from the start takes place according to the example in FIG. 2a.

Claims

Pa tent ü che 1. Process for the production of explosive charges from non-pourable mixtures, characterized in that an explosive mixture of 85-92.5% of a solid component and 7.5-15% of a fusible component on a around the melting point of the fusible component lying processing temperature is brought that the tempered and evenly mixed Sprengs toffmis chung then poured into a heated pressing tool, placed under vacuum and then placed under such a high pressing pressure that the fusible component instantaneously solidifies.

2. The method according to claim 1, characterized in that a very explosive explosive such as HMX, NQ, PETN, RDX, TATB and as a fusible component TNT, TNB or TNCB are used as the solid component.

3. The method of claim 2, d a d u r c h g e k e n n z e i c h n e t that the weight ratio RDX / TNT = 90/10 or 92.5 / 7.5.

4. The method of claim 2, d a d u r c h g e k e n n z e i c h n e t that the weight ratio HMX / TNT = 85/15.

5. The method according to any one of claims 1 and 4, d a d u r c h g e k e n n z e i c h n e t that the

Explosives mixture plastics as binders, desensitizing agents, plasticizers and / or wall adhesives are added.

6. The method according to any one of claims 1 to 5, d a d u r c h g e k e n n z e i c h n e t that the

The explosive mixture is only heated to a temperature just below the melting point of the meltable components, so that the explosive mixture is then poured into a heated pressing tool by means of a metering device, heated to a processing temperature around the melting point of the meltable component and then pressed.

7. The method according to any one of claims 1 to 6, characterized in that the individual grain (5) of the solid explosive component is first coated with a thin shell (6) of a thermoplastic or reactive binder, and that this grain is then coated with the meltable explosive .

8. The method according to any one of claims 1 to 6, characterized in that the individual grain (5) of the solid explosive material component is first provided with a thin shell (7) of the meltable explosive, that the binder (8) is then applied and then this grain is coated with the meltable explosive.