US3271212A

US3271212A - Explosive with trinitrobenzene

Info

Publication number: US3271212A
Application number: US389805A
Authority: US
Inventors: Riedl Hans-Joachim; Frank Hermann; Sauermilch Walter
Original assignee: Wasag Chemie AG
Current assignee: Wasag Chemie AG
Priority date: 1963-08-17
Filing date: 1964-08-14
Publication date: 1966-09-06
Anticipated expiration: 1983-09-06
Also published as: DE1186383B; GB1009683A; BE651542A

Description

United States Patent 7 Claims. 61. 149-92 The present invention relates to a high explosive body and to a method of making the same.

The explosive mixtures which are used for producing .high explosive bodies consist usually of two components,

namely one explosive composition which has a relatively high melting point and frequently does not melt without decomposition, while the other consists of one or more explosive compositions of lower melting point and this other component serves in a larger or small proportion as the melting component.

Cast bodies of such mixtures of explosive compositions are generally made of mixtures of hexogen (cyclotrimethylenetrinitramine), octogen (cyclotetramethylenetetranitramine) or nitropenta (tetranitropentaerythritol) and trinitrotoluene, whereby the last mentioned compound serves as the melting component. The reasons why nearly exclusively trinitrotoluene is used for producing casting mixtures can be found in its advantageous melting temperature of 808 C. and the fact that it can be safely handled. On the other hand, the detonation speed of trinitrotoluene is only 6900 meters per second and thus, the detonation speed of the casting mixtures containing trinitrotoluene will be considerably below that of hexogen or nitropenta.

It has also been proposed to compress pulverulent explosives with the addition of a small amount of a melting component. Thus, for instance hexogen has been desensitized with between 10 'and 20% trinitrotoluene and the thus formed mixture has been compressed. In this manner a higher speed of detonation is obtained as can be obtained with conventional mixtures which have been compressed with the addition of wax. However, it is not possible in this manner to obtain the detonation speed of the pure compressed explosives. The density which can be obtained in this manner deviates even stronger from the theoretically obtainable density, since the explosive compositions which are used for desensitizing, such as trinitrotoluene are not as deformable as wax. Thus, a mixture consisting of 90% hexogen and 10% trinitrotoluene will result upon conventional compressing in an explosive body having a density which will be between and 8% below the theoretically obtainable maximum density.

It is therefore an object of the present invention to overcome the 'above discussed disadvantages.

It is a further object of the present invention to produce a particularly effective high explosive body which may be safely handled and which can be easily produced.

Other objects and advantages of the present invention will become apparent from a further reading of the description and of the appended claims.

With the above and other objects in view, the present invention contemplates a high explosive body consisting essentially of an intimate mixture of a first explosive ice composition and a second explosive composition, the second explosive composition being selected from the group consisting of (a) mixtures of between about and 90% by weight trinitrobenzene and between about 30 and 10% by weight trinitro'toluene, and (12) mixtures of between about 20 and by weight of trinitrobenzene and between about 80 and 20% by weight of tetryl, the first explosive composition having a significantly higher melting point than the second explosive composition.

The present invention is also concerned with a method of producing a high explosive body which comprises the steps of forming an intimate mixture of between and 98% by weight of a first explosive composition selected from the group consisting of cyclotrim'ethylenetrini'tramine, cyclotetrame'thylenetetranitramine and tetranitropent'aerythritol and between 10 and 2% by weight of a second explosive composition selected from the group consisting of (a) mixtures of between about 70 and 90% by weight trinitrobenzene and between about 30 and 10% by weight trinitrotoluene, and (b) mixtures of between about 20 and 80% by weight of trinitrobenzene and between about 80% and 20% by weight of tetryl, subjecting the mixture to a partial vacuum, and compressing the thus evacuated mixture at the melting temperature of the second explosive composition so as to form a pressed high explosive body of the first and second explosive compositions.

According to another embodiment, the method of producing a high explosive body according to the present invention comprises the steps of forming an intimate mixture of between 50 and 80% by weight of a first explosive composition selected from the group consisting of cyclotrimethylenetrinitramine, cyclotetramethylenetetranitramine and tetranitropentaerythritol and between 50 and 20% by weight of a second explosive composition selected from the group consisting of (a) mixtures of between about 70 and 90% by weight trinitrobenzene and between about 30 and 10% by weight trinitrotoluene, and (b) mixtures of between about 20 and 80% by weight of trinitrobenzene and between about 80% and 20% by weight of tetryl, and casting the thus formed mixture so as to form thereof a cast high explosive body.

It has thus been found that particularly effective high explosive bodies which may be safely hand-led and are easily produced in an economical manner, are obtained by using as the melting component a mixture which con sists essentially of between 70 and 90% trinitrobenzene and between about 30 and 10% trinitrotoluene. All percentage figures in the present specification are percent by weight.

Another mixture which may be advantageously used as the melting component according to the present invention consists of about 2080% trinitrobenzene and between about 80 and 20% te't-ryl (trinitrophenyl-methyh nitramine).

Mixtures of between 20 and 80% trinitrobenzene and between 80 and 20% tetryl solidify below 100 C. and are at such temperatures fully stable. They have a detonation speed of between 7300 and 7500 meters per second.

When high explosive bodies are to be produced by Patented Sept. 6, 1966' 3 octogen or nitropenta, the balance being the low melting mixture described above, while in the case of cast high explosive bodies, the high melting component such as hexogen, octogen or nitropenta will form between about meters per second), although the proportion of the melting component is relatively high and consequently easy casting is assured. The new melting components can be utilized in all conventional casting methods for ex- 50 and 80% of the explosive body and the balance 5 plosives which are used 'for obtaining homogeneous will again be formed by one of the above described mixcastings, for instance also under vacuum. As a nontures of either trinitrobenzene and trinitrotoluene or nitromelting component, particularly hexogen, octogen and benzene and tetryl. nitropenta have been found to give very good results.

The utilization of the above described melting com- In addition to the data given in the table, it was found ponent within the indicated proportions will result in the that very good results are also obtained by casting mixproduction of high explosive bodies of an effectiveness tures formed of between 20 and 50% of a mixture of or explosive yield which up to now could not be achieved. about 7090% trinitrobenzene and between about 30 and The detonation speed which is obtained with the high 10% trinitrotoluene, with between 50 and 80% hexogen, explosive bodies according to the present invention is nitropenta or oct-ogen. approximately the same as that obtained with compressed Examples and data for producing pressed high 'eX- pure hexogen or nitropenta. plosive bodies according to the present invention are Table 1 below describes the pertinent data which are summarized in Table 2. V obtained with cast bodies produced according to the The compressed charges of Table 2 first section are present invention, as compared with cast bodies proprepared as follows. duced according to the prior art of hexogen and trinitro- 30 g. trinitrobenzene is intimately mixed with 10 g. l trinitrotoluene in a heatable copper vessel and heated to EXAMPLE about 90 C. until both components are completely molten; then the mass is allowed to cool down by perma- 50 g. trinitrobenzene is mixed with 50 g. tetryl with nent stirring. a rubber-coated stirrer in a heatable evacuable copper 10 parts of this mixture are mixed with 90 parts of vessel. The mixture is heated in a steam bath until hexogen and the mass is heated to about 90 C. This the mass is completely molten and the temperature is mixture is filled into an evacuable matrix mm. diabout 95 C. 100 g. hexogen is added in 3-4 portions ameter) which has previously been heated to 90 C. to the so prepared molten mass and the mixture is The press die is placed on the mass and a compression stirred to a homogeneous mass, the temperature being 30 of 1250 kg./cm. is effected. The pressure is mainkept at 95 C. Then the apparatus is evacuated by tained until the matrix has cooled down to 30-40 C. means of an oil pump and the vacuum is maintained for The so obtained compressed charge has a density of 15 minutes at less than 1 mm. Hg. After the vacuum is 1.77 g./cm. The detonation velocity was found to be removed the mixture is cast at about 95 C. in a cylindric 8350 m./sec.

Table 2 Explosive Mixture Press Press Air Detonation Power, Tempera- Pressure, Cooling Density Speed, kglcm. ture, C. mm. Hg n1./sec. Solid Component Meltable Component 90%l1exogen 10% of a mixture of trinitrobenzene- 1,200 90 10 Cooling under pressure"-.. 1. 77 8,350

trinitrotolueue 3:1. 95% hexogen" 5% of a mixture of trinitrobenzene 1, 200 90 10 .do 1.78 9, 400

trinitrotoluene 3:1. 95% hexogen 5% o! a mixture of trinitrobenzene 1, 200 90 10 Expelled while still warm.-. 1. 73 8, 300

trinitrotolu ne 3:1.

mold of 25 mm. diameter and allowed to cool. The The best explosive bodies are prepared according to so obtained explosive column detonates at a velocity of the present invention by compressing the mixture of the 8000 m./ sec. explosive components at a temperature at which the lower Table I melting component is completely or partially molten and, preferably, compression of the mixture is carried out impactsensj. under a partial vacuum. Surprisingly it has been found was... attests. artist, imitat the e 1e peeeele m the w e eelefively. very 10 g mim small proportion of the lower melting component in the ex losive mixture to produce homogeneous and mechani- 50% hexogen cally resistance high explosive bodies. The density of the @823 570 i thus produced high explosive body is only slightly be- 40% trinitrotoluene e660 as low the theoretically possible maximum density and this 22;: gfiffifigg g- 8,000 435 06 is achieved by carrying out the compression under a 25% tetryl partial vacuum, in other words, to subject the mixture to ggZ l f 8,200 445 as subatmosplreric pressure, for instance of 10 millimeter m r ry and to maintain this subatmospheric pressure 66.7% hexogen 20.0% trinitorbenzena} 8,250 450 0.0 d thus a very low gas content during the compressing fi g of the mixture. 133% trinit rob enzer la} 8,300 455 0.6 The method of producing pressed high explosive bodies gg yofiiietlrggnm according to the present invention can be carried out 2472 trinitroben'ziiif 8,000 450 0.4 for instance by placing the press mold and the explosive 16% tetryl mixture into a Warming cabinet so that the mold as Well 1 I as the mixture will be heated up to a temperature at Exploswsmfie Barthe Mannheim) 1958 which the lower melting component of the explosive mix- It will be seen that the cast mixtures which include ture will be liquefied. Thereafter, the mold and the exthe melting component or mixture according to the plosive mixture are quickly introduced into the press, present invention will give a detonation speed of up to evaporated and thereafter the mixture is compressed. 8300 meters per second, i.e. values which are close to The press molds are preferably fitted with rubber rings those obtained with pure hexogen and nitropenta (8400 of circular cross section or other suitable packings and are formed with a conduit for evacuating the interior of the press mold.

In order to obtain pressed bodies which conform fully to the shape of the mold, it is preferred to maintain the mold under pressure until the molten component of the explosive composition is again solidified, or to resiliently lock the mold after the same has been subjected to pressure, then to remove the locked mold, the interior of which is thus continued to be maintained under pressure, from the press and allow cooling off of the contents to take place outside of the press.

Although it is preferred, and the b'est results are achieved when the pressed body is maintained in the mold under compression until it is completely solidified, nevertheless, it is also possible to obtain the desired effect of increasing density and detonation speed when the pressed body is removed from the mold before the molten component of the body has been fully solidified.

Carrying out the method of the present invention is facilitated by using heatable press molds. For instance, the press molds may be heated electrically however, it is more desirable to provide the press form with conduits through which a heating fluid may pass.

Another manner in which the production of pressed high explosive bodies according to the present invention could be speeded up consists in the use of press forms which have a hot and a cold zone which can be achieved easily by passing heating and cooling liquids, respectively through the respective zones of the press mold. In this case, the preheated mixture is introduced into the hot or warm zone of the press mold, and compressed therein. Thereafter, the sleeve portion of the mold is moved relative to the press punch in such a manner that the pressed body may then be solidified while being located in the cold zone of the press.

By carrying out the warm pressing method of the present invention under a partial vacuum, for instance of a residual pressure of mm. mercury, densities of the pressed body are obtainable which are only about 1% below the theoretically possible maximum density. The thus produced pressed bodies, depending on their composition, possess detonation speeds which are higher than those of pressed bodies formed of pure high explosive compositions.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. A high explosive body consisting essentially of an intimate mixture of a first explosive composition and a second explosive composition, said second explosive composition being selected from the group consisting of (a) mixtures of between about 70 and 90% by weight trinitrobenzene and between about 30 and 10% by weight trinitrotoluene, and (b) mixtures of between about and 80% by weight of trinitrobenzene and between about 80 and 20% by weight of tetryl, said first explosive composition having a significantly higher melting point than said second explosive composition.

2. A high explosive body consisting essentially of an intimate mixture of a first explosive composition selected from the group consisting of cyclotrimethylenetrinitramine, cy-clotetramethylenetetranitramine and tetranitropentaerythritol, and a second explosive composition, said second explosive composition being selected from the group consisting of (a) mixtures of between about 70 and 90% by weight trinitrobenzene and between about and 10% by weight trinitrotoluene, and (b) mixtures of between about 20 and by weight of trinitrobenzene and between about 80 and 20% by Weight of tetryl, said first explosive composition having a significantly higher melting point than said second explosive composition.

3. A pressed high explosive body consisting essentially of an intimate mixture of between and 98% by weight of a .first explosive composition selected from the group consisting of cyclotrimethylenetrinitramine, cyclotetramethylenetetranitramine and tetranitropentaerythritol, and between 10 and 2% by weight of a second explosive composition, said second explosive composition being selected from the group consisting of (a) mixtures of between about 70 and 90% by weight trinitrobenzene and between about 30 and 10% by weight trinitrotoluene, and (b) mixtures of between about 20 and 80% by weight of weight of trinitrobenzene and between about 80 and 20% by weight of tetryl, said first explosive composition having a significantly higher melting point than said second explosive composition.

4. A cast high explosive body consisting essentially of an intimate mixture of between 50 and 80% by weight of a first explosive composition selected from the group consisting of cyclotrimethylenetrinitramine, cyclotetramethylenetetranitramine and tetranitropentaerythriol, and between 50 and 20% by weight of a second explosive composition, said second explosive composition being selected from the group consisting of (a) mixtures of between about 70 and 90% by weight trinitrobenzene and between about 30 and 10% by weight trinitrotoluene, and (b) mixtures of between about 20 and 80% by weight of trinitrobenzene and between about 80 and 20% by weight of tetryl, said first explosive composition having a significantly higher melting point than said second explosive composition.

5. A method of producing a high explosive body comprising the steps of forming an intimate mixture of between 90 and 98% by weight of a first explosive composition selected from the group consisting of cyclotrimethylenetrinitramine, cyclotetramethylenetetranitramine and tetranitropentaerythritol and between 10 and 2% by weight of a second explosive composition selected from the group consisting of (a) mixtures of between about 70 and 90% by weight of trinitrobenzene and between about 30 and 10% by weight trinitrotoluene, and (b) mixtures of between about 20 and 80% by weight of trinitrobenzene and between about 80 and 20% by weight of tetryl; subjecting said mixture to a partial vacuum; and compressing the thus evacuated mixture at the melting temperature of said second explosive composition so as to form a pressed high explosive body of said first and second explosive compositions.

6. A method of producing a high explosive body comprising the steps of forming an intimate mixture of be tween 50 and 80% by weight of a first explosive composition selected from the group consisting of cyclotrimethylenetrinitramine, cyclotetramethylenetetranitramine and tetranitropentaerythritol and between 50 and 20% by weight of a second explosive composition selected from the group consisting of (a) mixtures of between about 70 and 90% by weight trinitrobenzene and between about 30 and 10% by weight trinitrotoluene, and (b) mixtures of between about 20 and 80% by weight of trinitrobenzene and between about 80% and 20% by weight of tetryl; and casting the thus formed mixture so as to form thereof a cast high explosive body.

7. A method of producing a high explosive body comprising the steps of forming an intimate mixture of between 90 and 98% by weight of a first explosive composition selected from the group consisting of cyclotrimethylene trinitramine, cyclotetramethylenetetranitramine and tetranitropentaerythritol and between 10 and 2% by weight of a second explosive composition selected from 7 the group consisting of (a) mixtures of between about 70 and 90% by weight trinitrobenzene and between about 30 and 10% by weight trinitrotoluene, and (b) mixtures of between about 20 and 80% by weight of trinitrobenzene and between about 80 and 20% by weight of tetryl; subjecting said mixture to a subatmospheric pressure of about 10 mm. mercury; and compressing the thus evacuated mixture at a pressure of about 1,200 kg./cm. and at a temperature at which at least a portion of said sec- 8 to form a pressed high explosive body of said first and second explosive compositions.

References Cited by the Examiner Bebie, 1.: Manual of Explosives-Military Pyrotechnics and Chemical Warfare Agents, Macmillan Co., N.Y., 1943 (p. 152).

BENJAMIN R. PADGETT, Acting Primary Examiner.

0nd explosive composition will be in molten state so as 10 S. J. LECHERT, Assistant Examiner.

Claims

1. A LHIGH EXPLOSIVE BODY CONSISTING ESSENTIALLY OF AN INTIMATED MIXTURE OF A FIRST EXPOSIVE COMPOSITION AND A SECOND EXPLOSIVE COMPOSITION, SAID SECOND EXPLOSIVE COMPOSITION BEING SELECTED FROM THE GROUP CONSISTING OF (A) MIXTURES OF BETWEEN ABOUT 70 AND 90% BY WEIGHT TRINITROBENZENE AND BETWEEN ABOUT 30 AND 10% BY WEIGHT TRINITROTOLUENE, AND (B) MIXTURES OF BETWEEN ABOUT 20 AND 80% BY WEIGHT OF TRINITROBENZENE AND BETWEEN ABOUT 80 AND 20% BY WEIGHT OF TETRYL, SAID FIRST EXPLOSIVE COMPOSITION HAVING A SIGNIFICANTLY HIGHER MELTING POINT THAN AND SECOND EXPLOSIVE COMPOSITION.