RU2378240C2 - Porous spherical moistureproof powder for shot-gun cartridges for smooth-bore arms - Google Patents

Abstract

FIELD: explosives.

SUBSTANCE: invention is related to production of spherical powders. Porous spherical moistureproof powder for shot-gun cartridges of smooth-bore arms comprises nitrocellulose with NO content of at least 200 ml/g, nitroglycerin, diphenylamine, centralite, ethyl acetate, moisture and graphite with particle size of 0.1…4.0 mcm, distributed along powder surface and in pores produced on powder surface.

EFFECT: aimed at increase of moisture resistance of porous spherical powder.

3 tbl

Description

The invention relates to the production of spherical powders and can be used to equip shot cartridges for sports and hunting smoothbore weapons.

Known gunpowder for hunting rifles (RF patent No. 1779685, IPC 7 C06B 25/24, priority 02.04.90), containing nitrocellulose, diphenylamine, ethyl acetate, lead oxide, carbon black (soot), moisture and graphite in the following ratio of components in the composition (wt.%):

 lead oxide 1,0 ... 4,0  carbon black (soot) 0.2 ... 1.0  diphenylamine 0.3 ... 0.9  ethyl acetate 0.7 ... 1.5  moisture 0,1 ... 0,4  graphite 0,1 ... 0,3  nitrocellulose containing NO at least 213.0 ml / g rest

The specified powder has insufficient moisture resistance due to its hygroscopicity inherent in pyroxylin powders. Since hunting cartridges after assembly are not sealed products, their storage in high humidity conditions can lead to wetting of the propellant charge placed in them from the specified powder and, as a result, to a decrease in its ballistic characteristics. In addition, gunpowder can absorb moisture during the assembly of cartridges when it is outside the sealed container.

There is porous spherical gunpowder for equipping cartridges of military, sports and hunting weapons - a prototype (Brief Encyclopedic Dictionary "Energy Condensed Systems", edited by B. P. Zhukov, M., Janus-K, 2000, pp. 425-427), including nitrocellulose, nitroglycerin, diphenylamine, phlegmatizers, moisture, residual solvent and graphite, in the following ratio of components (wt.%):

 nitroglycerine 0 ... 25  diphenylamine 0.5 ... 1.0  phlegmatizers (dibutyl phthalate, centralit or dinitrotoluene) 3 ... 8  moisture 0,1 ... 0,3  graphite 0.2 ... 1.5  residual solvents (ethyl acetate, methyl acetate or nitromethane) 0,1 ... 0,3  nitrocellulose (12-13.5 wt.% nitrogen) rest

The presence of dinitrotoluene in the composition of this powder really reduces its hygroscopicity. However, the powder still absorbs moisture, although to a lesser extent, which makes it possible to use it only as part of a sealed cartridge. In this case, a decrease in hygroscopicity is sufficient to protect the powder from moisture only at the cartridge assembly phase. A longer residence of gunpowder in conditions of high humidity, including as part of hunting and sports shot cartridges during their storage, will lead to a change in the ballistic characteristics of the propellant charge due to the moisture of the gunpowder.

The technical task of the invention is to increase the moisture resistance of porous spherical powders used to equip shot-hunting and sporting cartridges for smooth-bore weapons.

The technical problem is solved due to the fact that in porous spherical powder containing nitrocellulose, nitroglycerin, diphenylamine, centralite, ethyl acetate, moisture and graphite, graphite grade C1 is used, fine, with a particle size of not more than 4.0 μm (we considered range 0 , 1 ... 4.0 microns), with the following ratio of the constituent components (wt.%):

nitroglycerine 4.0 ... 9.0  diphenylamine 0.3 ... 1.5  centralizes 0,1 ... 0,4  graphite 0,1 ... 0,4  moisture 0.8 ... 1.2  ethyl acetate 0.01 ... 0.7  nitrocellulose containing NO at least 200 ml / g rest

Since the particle sizes of the finely dispersed graphite grade С1 used for graphitization of gunpowder are commensurate with the pore sizes in the powder elements, in addition to the graphite distribution on the surface of the powder, graphite is blocked by pores of finely dispersed graphite. Since in porous powders, including spherical, moisture is mainly absorbed through the pores, their blockage with fine graphite leads to an increase in the moisture resistance of the powder. Previously used for graphitization of gunpowder, graphite grade C3 with larger particles (up to 30 μm), the sizes of which are incommensurable with the size of the pores, does not provide clogging of the pores and does not increase the moisture resistance in this case.

The moisture content in the powder in the range of 0.8 ... 1.2% (in existing spherical gunpowder for shot cartridges is less than 0.8%) also helps to reduce the hygroscopicity of gunpowder because it shifts the dynamic balance to reduce the ability of the gunpowder to absorb moisture.

The gunpowder of the recipe proposed by the authors was subjected to physico-chemical and ballistic tests for compliance with the requirements of the current regulatory and technical documentation, which accepts sports and hunting gunpowders, in particular, TU 7506804-164-93 for the spherical gunpowder Sunar SHS. The following characteristics were determined:

- chemical resistance (gauge test), mm Hg, according to TU no more than 60;

- the average flight speed of the fraction, m / s, according to TU not less than 340;

- the spread of the flight speed of the fraction, m / s, according to TU no more than 15;

- the average maximum pressure of the powder gases in the bore, kgf / cm ² , according to TU no more than 630.

Ballistic tests of cartridges were carried out with humidified and moistened gunpowder. Humidification of gunpowder was carried out by holding it in an atmosphere with 80% relative humidity for 3 hours.

Table 1 presents the test results of the powder of the proposed formulation within the boundary values of the ratio of the components in the composition. Three compositional options were tested: with a maximum (pr. 1), minimum (pr. 2) and average (pr. 3) value of the content of components. In this case, C1 grade graphite with a particle size of 4.0 μm was used.

As can be seen from the table, the considered compositions of the proposed formulation have the values of the determined characteristics within the normative values. So, with a charge mass of 1.42 ... 1.45 g tests of cartridges with moistened gunpowder showed that the average flight speed of the fraction is 342 ... 346 m / s; the spread of the flight speed of the fraction is 11 ... 15 m / s; the average maximum pressure of the powder gases in the bore is 600 ... 615 kgf / cm ² . In this case, the chemical resistance of the powders is in the range of 30 ... 35 mm Hg. The known composition intended for equipping 5.6 mm cartridges showed, when tested in 12-round cartridges, respectively, the following characteristics: 335 m / s, 20 m / s, 685 kgf / cm ² with a charge mass of 1.65 g.

When testing cartridges with moistened powder of the proposed formulation, the ballistic characteristics practically did not change and amounted to 341 ... 344 m / s, 11 ... 15 m / s, 586 ... 600 kgf / cm ^2, respectively. While the known composition has a significant decrease in ballistic characteristics to 315 m / s, 21 m / s, 595 kgf / cm ² , respectively. Thus, the proposed composition within the boundary values provides the required moisture resistance, while the known composition shows high hygroscopicity in comparison with the proposed composition.

Table 1 Name of indicator According to the composition developed by the authors According to the known composition (prototype) pr.1 pr.2 pr 3 one 2 3 four 5 2. Composition, wt.% - nitroglycerin 4.0 7.0 9.0 12.5 - diphenylamine 0.3 0.9 1,5 0.7 - central 0.1 0.25 0.4 - - graphite grade C1 (4.0 μm) 0.1 0.25 0.4 - moisture 0.8 1,0 1,2 0.2 - ethyl acetate 0.01 0.35 0.7 0.2 - dinitrotoluene - - - 5,0 - regular coarse graphite grade C3 1,0 - nitrocellulose with an NO content of at least 200 ml / g 94.69 90.25 86.8 - nitrocellulose with a nitrogen content in the range of 12-13.5 wt.% 81.4 3. Resistance, (pressure gauge. Sample) mm Hg thirty 35 thirty 35 4. Ballistic charge characteristics in a sports cartridge of 12 caliber with a fraction of 24 g (before wetting) - mass of charge, g 1.45 1.43 1.42 1.65 - the average flight speed of the fraction, m / s 342 345 346 335 - the spread of the flight speed of the fraction, m / s 12 fifteen eleven twenty - the average maximum pressure of the powder gases in the bore, kgf / cm ² 600 610 615 685 5. Ballistic charge characteristics (after wetting) - the average flight speed of the fraction, m / s 341 345 344 315 - the spread of the flight speed of the fraction, m / s fifteen eleven fourteen 22 - the average maximum pressure of the powder gases in the bore, kgf / cm ² 586 596 600 595

Table 2 shows the test results of similar compositions (pr 1, 2, 3), in which graphite was used with particle sizes, mainly 0.1 microns. As can be seen from the table, the ballistic characteristics of cartridges with moistened and moistened gunpowder are almost the same and have the following values with a charge mass of 1.43 ... 1.45 g. With wet powder: the average flight speed of the shot is 340 ... 348 m / s, the spread of the flight speed of the shot is 11 ... 14 m / s, the average maximum pressure of the powder gases is 600 ... 625 kgf / cm ² . With moistened powder, respectively: 340 ... 347 m / s, 11 ... 15 m / s, 580 ... 610 kgf / cm ² .

The test results indicate satisfactory moisture resistance of the powders, within the boundary values of the content of the components of the composition with the particle size of the graphite used 0.1 ... 4.0 microns.

Table 3 shows the test results of 12-gauge sports cartridges equipped with moistened and moistened gunpowder with a formulation in which one of the components goes beyond the boundary values. The particle sizes of the graphite used were 4.0 μm.

As can be seen from the table, when the nitroglycerin content is below the minimum (pr.1a), the average velocity is undersized (335 m / s), and when the value is higher than the maximum (pr.1b), there is an excess of the velocity dispersion (18 m / s) .

With a prohibitive minimum value of stabilizers of chemical resistance of diphenylamine and centralite (pr 2a, pr 3a), a decrease in the chemical resistance of gunpowder (65 and 58 mm Hg) is observed, where the value is 65 mm Hg higher than permissible. When exceeding the maximum value of centralite in the composition (Project 3b), there is a shortage in average speed (338 m / s). In the case of diphenylamine (Project 2b), an excess in the spread of the flight speed of the fraction (20 m / s) was obtained. Changing the graphite content to values that go beyond the boundary values, in particular, above the maximum (pr.4b), leads to an excess in the spread of the fractional flight speed (22 m / s). In the case of an increase in the moisture content above the maximum value (pr. 5b), a shortage in average speed (335 m / s) was obtained. It is technologically impossible to reduce the ethyl acetate content below the minimum value, therefore, a composition with an ethyl acetate content above the boundary value was tested, and a shortfall in average velocity (332 m / s) and an excess in speed dispersion (19 m / s) were obtained.

table 2 Name of indicator According to the composition developed by the authors pr.1 pr.2 pr 3 1. Composition, wt.% - nitroglycerin 4.0 7.0 9.0 - diphenylamine 0.3 0.9 1,5 - central 0.1 0.25 0.4 - graphite (0.1 μm) 0.1 0.25 0.4 - moisture 0.8 1,0 1,2 - ethyl acetate 0.01 0.35 0.7 - nitrocellulose with an NO content of at least 200 ml / g 94.69 90.25 86.8 2. Resistance, (pressure gauge. Sample), mm Hg 40 thirty 35 3. Ballistic charge characteristics in a 12-gauge sports cartridge with a shot mass of 24 g (before wetting) - mass of charge, g 1.45 1.44 1.43 - the average flight speed of the fraction, m / s 340 348 345 - the spread of the flight speed of the fraction, m / s eleven 12 fourteen - average max. pressure of powder gases in the bore, kgf / cm ² 610 625 600 4. Ballistic charge characteristics (after wetting) - the average flight speed of the fraction, m / s 340 347 344 - the spread of the flight speed of the fraction, m / s fifteen eleven fourteen - the average maximum pressure of the powder gases in the bore, kgf / cm ² 590 610 580

Table 3 Name of indicator pr.1 pr.2 pr 3 pr.4 pr 5 pr.6 one 2 3 four 5 6 7 1. Composition, wt.% - nitroglycerin a) 3.0; b) 10.0 7.0 7.0 7.0 7.0 7.0 - diphenylamine 0.9 a) 0.2; b) 2.0 0.9 0.9 0.9 0.9 - central 0.25 0.25 a) 0.05; b) 0.5 0.25 0.25 0.25 - graphite (4.0 μm) 0.25 0.25 0.25 a) 0.05; b) 0.5 0.25 0.25 - moisture 1,0 1,0 1,0 1,0 a) 0.7; b) 1.3 1,0 - ethyl acetate 0.35 0.35 0.35 0.35 0.35 0.9 - nitrocellulose with an NO content of at least 200 ml / g rest rest rest rest rest rest 2. Resistance (pressure gauge. Sample), mm Hg a) 30 a) 65 a) 58 a) 38 a) 31 39 b) 35 b) 40 b) 34 b) 49 b) 41 3. Ballistic charge characteristics in a 12-gauge cartridge with a shot mass of 24 g (before wetting) - mass of charge, g a) 1.70 a) 1.55 a) 1.53 a) 1.56 a) 1.57 1,61 - b) 1.50 b) 1.60 b) 1.59 b) 1.53 b) 1.80 - the average flight speed of the fraction, m / s a) 335 a) 345 a) 341 a) 340 a) 343 332 b) 355 b) 340 b) 338 b) 341 b) 335 - the spread of the flight speed of the fraction, m / s a) 15 a) 12 a) 12 a) 11 a) 15 19 b) 18 b) 20 b) 15 b) 22 b) 18 - the average maximum pressure of the powder gases in the bore, kgf / cm ² a) 645 a) 625 a) 610 a) 595 a) 625 628 b) 630 b) 640 b) 600 b) 605 b) 630 4 Ballistic charge characteristics in a 12-gauge cartridge with a shot mass of 24 g (after wetting) - the average flight speed of the fraction, m / s a) 325 a) 330 a) 335 a) 318 - the spread of the flight speed of the fraction, m / s a) 12 a) 15 a) 16 a) 10 - the average maximum pressure of the powder gases in the bore, kgf / cm ² a) 590 a) 510 a) 525 a) 505

Thus, cartridges with moistened gunpowder of the following formulations were subjected to subsequent ballistic tests: pr.2a; pr.3a; pr 4a; pr.5a, which in their characteristics met the requirements of TU. Tests of these compositions showed a drop in ballistic characteristics of charges from wet powder: average speed up to 318 ... 330 m / s, average maximum pressure of powder gases up to 505 ... 590 kgf / cm ² , which indicates their lack of moisture resistance.

It follows from the foregoing that compositions comprising components whose contents exceed the limits of the boundary values do not meet the requirements, which indicates the correctness and reliability of the selected ratio of the components of the composition.

As for the limiting values of the range of particle sizes of graphite (0.1 ... 4.0 μm), it should be noted the inappropriateness of using a fraction of graphite with particle sizes less than 0.1 μm, due to the small quantities of this fraction in the smallest grade of graphite produced by domestic industry ( graphite grade C1).

The effect on the moisture resistance of gunpowder with average values of the content of components, including graphite with particle sizes of 5.0 ... 6.0 microns (above the upper limit of the declared range), is shown in table 4.

As can be seen from the table, the composition with average values of the content of the components, including graphite with particle sizes of 5.0 ... 6.0 μm, after wetting shows a decrease in ballistic characteristics: the average flight speed of the fraction from 344 to 337 m / s and the average maximum pressure of powder gases in the bore from 610 to 530 kgf / cm ² . It can be assumed that the powder is moistened due to the penetration of moisture through pores that are not sufficiently covered by coarser graphite.

Table 4 Composition, wt.% Chemical resistance, mmHg Mass of charge, g Ballistic charge characteristics in a sports cartridge of 12 klb with a fraction of 24 g before moisturizing after wetting average flight speed of a fraction, m / s spread of the flight speed of a fraction, m / s average max powder gas pressure
kgf / cm ² average flight speed of a fraction, m / s spread of the flight speed of a fraction, m / s average max powder gas pressure, kgf / cm ² - nitroglycerin 7.0 - diphenylamine 0.9 - central 0.25 - graphite (5.0-6.0 μm) 0.25 38 1.43 344 12 610 337 fourteen 530 - moisture 1,0 - ethyl acetate 0.35 - nitrocellulose with a content of NO not less 200 ml / g 90.25

From the above it follows that the selected range of particle sizes of graphite (0.1 ... 4.0 microns) is sufficiently reliable.

Thus, the composition proposed by the authors makes it possible to increase its moisture resistance due to the selected fineness of graphite 0.1 ... 4.0 μm and a high moisture content of 0.8 ... 1.2% with an appropriate ratio of its constituent components.

Claims (1)

Porous spherical moisture-resistant powder for shotgun cartridges for smoothbore weapons containing nitrocellulose, nitroglycerin, diphenylamine, centralite, ethyl acetate, moisture and graphite, characterized in that it contains graphite with a particle size of 0.1 ... 4.0 μm distributed over the surface of the powder and in pores located on the surface of the powder, in the following ratio of components, wt.%:
nitroglycerine 4.0 ... 9.0 diphenylamine 0.3 ... 1.5 centralizes 0,1 ... 0,4 graphite 0,1 ... 0,4 moisture 0.8 ... 1.2 ethyl acetate 0.01 ... 0.7 nitrocellulose containing NO at least 200 ml / g rest