RU2293074C1 - Water-containing blasting composition - Google Patents

Abstract

FIELD: explosives.

SUBSTANCE: invention relates to water-containing explosives based on gel-like matrix sensitized by powerful blasting compositions and aluminum. Invention provides water-containing blasting composition containing sensitizer, ammonium nitrate, sodium nitrate, water? polyacrylamide, potassium bichromate, sodium thiosulfate, and monopotassium phosphate. As sensitizer, reusable hexogen and aluminum-based explosive removed from ammunition is used. Water-containing blasting composition may contain up to 40% grainy or crushed pyroxylin powder or crushed ballistite powder.

EFFECT: enabled manufacture of stable gel-like sensitized aluminum-containing blasting composition.

2 cl, 2 tbl

Description

The invention relates to the field of water-containing industrial explosives based on a gel-like matrix sensitized by powerful explosive compositions with aluminum additives extracted from high-power ammunition.

The known composition (US Pat. RF No. 2203258 from 04/27/2003), including the liquid phase based on an inorganic oxidizing agent and blasting explosive. As a liquid phase, it contains a 45-b5% aqueous or water-glycol solution of an inorganic oxidizer, and as a blasting explosive it contains hexogen and / or octogen in the following ratio of components, wt.%: 45-65% aqueous or water-glycol solution of an inorganic oxidizing agent - 5-25; RDX and / or HMX - 95-75.

The known composition has a high detonation ability, high power. The disadvantages of the known composition is the increased danger of use associated with a high content of hazardous explosives in circulation (RDX or HMX) and, accordingly, a low content of phlegmatized aqueous solution. Reducing the risk of handling this composition can be achieved by increasing the content of the phlegmatizing solution. However, in this case, in the absence of structuring additives, the composition will delaminate and accordingly lose uniformity. In addition, pure RDX and HMX were not used to equip ammunition.

Also known is a water-containing powder explosive composition (US Pat. RF No. 2183209 of 06/10/2002), taken as a prototype, including 40.0-65.0% of pyroxylin powder or mixtures thereof with ballistic powder, used as a sensitizer, 6.0- 15.0% sodium nitrate, 4.0-10.0% organic fuel, 10.0-25.0% water, 0.3-2.0% polyacrylamide, 0.01-0.1% potassium dichromate, 0 , 02% -0.2% sodium thiosulfate, the rest is ammonium nitrate.

This composition has a high detonation ability, the use of polyacrylamide as a gelatinizer and potassium dichromate and sodium thiosulfate as a structuring agent provide ease of manufacture and high quality products based on this composition.

The disadvantage of this composition is the inability to use as a sensitizer powerful explosive compositions extracted from utilized ammunition, the composition of which includes aluminum. Aluminum, included in the formulation of such compositions, reacts with an aqueous solution of ammonium nitrate, which is part of the gel-like matrix, reducing the stability of the composition during storage.

The objective of the present invention is to ensure the stability of gel-like explosive compositions sensitized by explosives, the formulation of which includes aluminum.

The problem is solved in that in the composition, which includes a sensitizer, ammonium nitrate, sodium nitrate, water, polyacrylamide, potassium dichromate and sodium thiosulfate, potassium phosphate monosubstituted is additionally contained, and utilized hexane-derived aluminum extracted from ammunition is used as a sensitizer in the following ratio of components, wt.%:

Sensitizer 20-60

Sodium Nitrate 4-16

Water 10-30

Polyacrylamide 0.3-2.5

Sodium thiosulfate 0.02-0.2

Potassium Dichromate 0.01-0.1

Potassium Phosphate 0.03-0.1

Ammonium nitrate - the rest.

In addition, the composition may additionally contain pyroxylin or ballistic powder, while its content is 10-40 wt.%.

The essence of the invention lies in the fact that potassium phosphate, introduced into the matrix, forms a protective film on the surface of aluminum particles that prevents the interaction of aluminum with an aqueous solution of ammonium nitrate.

In addition, when monosubstituted potassium phosphate is introduced into an aqueous solution of ammonium and sodium nitrates, a buffer medium with a pH of 4.5–5.5 is formed, which ensures high stability of the protective film on aluminum particles and, accordingly, the chemical resistance of the composition for a long time (up to 3 years) shelf life. At the same time, all the advantages of the prototype are preserved: high detonation ability, low sensitivity of the composition to mechanical stress, low combustibility and, accordingly, a high degree of safety when using products based on this composition. The minimum content of potassium phosphate, providing chemical stability of the composition, is 0.03%. With a lower content (example 2), chemical stability under conditions of long-term storage is not provided. An increase in the content of potassium phosphate in excess of 0.1% is not advisable, because does not lead to a further increase in the chemical stability of the composition.

The minimum content of sensitizer in the composition is 20%. With its lower content, the detonation ability sharply decreases, while the completeness of detonation in charges with a diameter of less than 100 mm is not ensured. The maximum content is 60%. With a higher content of sensitizer, shock sensitivity increases, while the necessary degree of safety during handling is not provided.

The ratios between water (10-30%), sodium nitrate (4-16%) and ammonium nitrate are taken so that all salts in the gel matrix are in the form of a solution at a sufficiently high concentration thereof. A high concentration of oxidizing agents ensures that the oxygen balance approaches zero to reduce the amount of toxic gases (CO) in detonation products and blasting. The content of polyacrylamide in an amount of 0.3-2.5% provides the viscosity of the gel-like matrix necessary for optimal conditions of the manufacturing process of the composition and stability of the composition during storage. With a lower content of polyacrylamide than 0.3%, the gel is structured at a very low speed and the required structural strength of the finished product is not provided. When the content of polyacrylamide is more than 2.5%, the viscosity of the matrix becomes too high, which complicates the process of mixing the matrix with a sensitizer. The content of potassium dichromate (0.01-0.1) and sodium thiosulfate (0.02-0.2) allows to control the structuring rate over a wide range and ensures the constant rheological characteristics during patronage and the stability of physicochemical and detonation characteristics under long-term storage sufficient strength of the structure of the composition.

The introduction of additionally grained or crushed pyroxylin or crushed ballistic gunpowder is advisable in cases where the content of hexogen-containing sensitizer is less than 30% to improve the manufacturing technology of the composition and prevent delamination of the composition during matrix structuring.

It should be noted that the explosive extracted from ammunition based on hexogen and aluminum can be used in the proposed composition both in powder form and in the form of pieces obtained by crushing the pieces.

To check the chemical resistance and assess the detonation characteristics, samples were prepared, the composition of which is given in table. one.

A method of manufacturing a gel-like matrix is as follows.

A portion of potassium phosphate monosubstituted is poured into a measured amount of water, then a mixture of ammonium nitrate is poured with stirring, then a mixture of sodium nitrate with polyacrylamide is also added with stirring. The whole mass with constant stirring is heated to a temperature of 50-60 ° C and allowed to completely swell and dissolve the polyacrylamide. Samples of sodium thiosulfate and potassium dichromate are introduced into the gel matrix thus obtained. The solution is mixed and a sensitizer is introduced in the form of powder or pieces obtained by crushing the pieces. The mass is thoroughly mixed. In the event that gunpowder is included in the formulation, it is poured together with a hexogen-containing sensitizer.

Assessment of the chemical resistance of the composition was carried out at a temperature of 80 ° C. To determine the chemical resistance, a tube with a diameter of 16–20 mm was filled with the composition and placed in a thermostat with a temperature of 80 ° С. In the absence of a chemical reaction between the solution of ammonium nitrate and aluminum, which is part of the sensitizer, the charge structure remained stable for 30 days, which corresponded to ensuring the stability of the composition when stored at room temperature for at least 12 months after the composition was prepared. At a low chemical resistance, a gas was released as a result of a chemical reaction between the ammonium nitrate solution and aluminum, and the mass swelled.

The brisance of the compositions was determined according to GOST 5984-79. The initiation of detonation was carried out by the detonator capsule No. 8. The average compression of lead columns was determined according to 2-3 experiments. Determination of brisance was carried out 48 hours after manufacture and for comparison after storage of charges for 6 months at room temperature.

The test results are shown in table 1.

Explosive compositions extracted from artillery ammunition and warheads of torpedoes and mines were used as a sensitizer: A-IX-2 (75% RDX, 5% phlegmatizer, 20% aluminum powder), a mixture of THAF (41% RDX, 40% TNT, 4% phlegmatizer, 15% aluminum).

From the analysis of the results of the table. 1 it follows that in the absence of a stabilizer (KH ₂ PO ₄ ) the composition has low chemical stability.

Example 1. The expansion of the composition occurred 1.5 days after the start of temperature control, which corresponds to maintaining the stability of the composition at room temperature for 20 days.

Example 2. When introducing into the composition of 0.02% of the stabilizer, the stability of the composition increases to 2 days (at room temperature about two months).

Example 3. With the introduction of a 0.03% stabilizer, the stability of the composition increases to 10 days (at room temperature for seven months).

In other examples, when the content of potassium phosphate is 0.06% or more, the chemical resistance of the composition increases to at least 30 days, which ensures the stability of the composition when stored at room temperature for more than 12 months.

The addition of up to 40% of gunpowder to the composition did not affect the chemical stability of the composition, regardless of whether ballistic or pyroxylin powder was used (Table 2).

From table 1 it is seen that the detonation properties of the compositions in the entire interval of changes of the components indicated in the formula, provide high detonation ability, which lasts for at least 6 months. Thus, the combination of features specified in paragraph 1 of the claims, ensures the achievement of a technical result.

Table 1 Component Content Examples one 2 3 four 5 6 7 8 9 10 A-ix-2 50 / p 50 / p 50 / p 50 / p 17 / p 20 / k 60 / p 45 / k - - TGAF mixture - - - - - - - - 30 / k 50 / k Sodium Nitrate 8 8 8 8 16 16 four eleven 12.8 8 Water 12 12 12 12 thirty thirty 10 22 32 12 Polyacrylamide one one one one 2,5 2,5 0.3 one one one Sodium thiosulfate 0.4 0.4 0.4 0.4 0.1 0.1 0.02 0.4 0.4 0.4 Potassium dichromate 0.2 0.2 0.2 0.2 0.05 0.05 0.01 0.2 0.2 0.2 Potassium phosphate - 0.02 0,03 0.1 0.1 0.1 0.06 0.1 0.1 0.1 Ammonium nitrate 28,4 28.38 28.37 28.3 34.25 31.25 25.61 20.3 23.5 28.3 The properties Brisance, mm 38 37 39 36 5 10 45 44 29th 37 Stability (80 ° C), days 1,5 2 10 over 30 thirty over 30 over 30 over 30 over 30 over 30

table 2 Component Content Examples eleven 12 13 fourteen fifteen 16 Pyroxylin gunpowder 40 twenty 10 - - - Ballistic gunpowder - - - 40 twenty 10 A-ix-2 20 / p 30 / p 25 / p 28 / p 28 / p 28 / p Sodium Nitrate four 8 10 four 8 12 Water 10 12 twenty 10 12 23 Polyacrylamide 0.3 one 1.4 0.3 one 1.7 Sodium thiosulfate 0.02 0.4 0.1 0.02 0.4 0.12 Potassium dichromate 0.01 0.2 0.05 0.01 0.2 0.06 Potassium phosphate 0.06 0,03 0,07 0.06 0,03 0.08 Ammonium nitrate 25.61 28.37 33.38 17.61 30.37 25.04 The properties Brisance, mm 27 29th 27 28 29th 27 Stability (80 ° C), days over 30 over 30 over 30 over 30 over 30 over 30

Claims (2)

1. A water-containing explosive composition, including a sensitizer, ammonium nitrate, sodium nitrate, water, polyacrylamide, potassium dichromate and sodium thiosulfate, characterized in that it additionally contains potassium phosphate monosubstituted, and a recyclable material extracted from ammunition is used as a sensitizer and aluminum in the following ratio of components, wt.%: Sensitizer 20-60 Sodium Nitrate 4-16 Water 10-30 Polyacrylamide 0.3-2.5 Sodium thiosulfate 0.02-0.2 Potassium dichromate 0.01-0.1 Potassium phosphate 0.03-0.1 Ammonium nitrate Rest 2. The aqueous explosive composition according to claim 1, characterized in that it further comprises up to 40% of granular or crushed pyroxylin powder or crushed ballistic powder.