RU2289562C1 - Refractory inflammable composition for electric igniter - Google Patents

Abstract

FIELD: pyrotechnical inflammable compositions.

SUBSTANCE: invention relates to compositions for electric igniters. Invention proposes the refractory inflammable composition for electric igniters comprising barium azide and methylcellulose, polyvinyl butyral or nitrocellulose as a binding agent with the nitration degree from 11.0 to 14.0. The invention is directed for the creature of refractory inflammable composition with low sensitivity to mechanical effects and possessing enhanced values of safety current and minimal current response. Invention can be used in manufacture of bridge electric initiating agents.

EFFECT: improved and valuable properties of composition.

1 tbl, 14 ex

Description

The invention relates to pyrotechnic igniter compositions for electric igniters and can be used in the manufacture of bridged electrical means of initiation (ESI).

It is known [1] that lead styphnate, explosive mercury and pyrotechnic mixtures containing zirconium and an oxidizing agent are used as an ignition charge in bridging ESI.

Known igniter composition for ESI [2], containing copper acetylenide, diazodinitrophenol, lead mononitroresorcinol, Bertholite salt. Next, a drop of igniter composition is coated with a layer of the following igniter composition, consisting of a mixture of ammonium picrate and potassium or carbon dichromate and a bertholite salt. The applied layers are fixed with a binder layer. The disadvantage of this invention is the multilayer coating, a very high sensitivity to mechanical stress and low heat resistance, as well as the complexity and duration of manufacture.

Known igniter composition for ESI [3], containing Bertholite salt and lead thiocyanate. The disadvantages of this composition include high sensitivity to mechanical stress (100% of operations when the load falls 200 g from a height of 4 cm) and low minimum operating current (0.3 A).

Closest to the present invention is a heat-resistant igniter composition [4] for electric igniters, containing, wt.%:

No. 1 Rodanide Lead 44 ÷ 50 Number 2 Potassium perchlorate 60 ÷ 70 Potassium perchlorate 50 ÷ 49 Potassium picrate 40 ÷ 30 Chromate Lead 6 ÷ 1

The disadvantages of the prototype composition include insufficiently low sensitivity to mechanical stress (100% of operations when the load falls 200 g from a height of 100 ÷ 120 cm), low values of safe current (0.3 ÷ 0.4 A) and the minimum operating current (0 , 4 ÷ 0.5 A), as well as the content of toxic lead compounds in the formulation.

An object of the invention is the creation of an igniter composition for an electric igniter, the heat resistance is not inferior to the composition of the prototype, not containing lead compounds, with low sensitivity to mechanical stress and with increased values of safe current and minimum operating current.

The problem is solved in that the proposed igniter composition for electric igniters contains barium azide and a binder with the following components, wt.%:

barium azide 94.0 ÷ 99.6 binder rest

As a binder, methyl cellulose, polyvinyl butyral, nitrocellulose with a degree of nitration from 11.0 to 14.0 are used.

The technical result consists in the fact that the above components are used for the first time in the proposed combination for the preparation of a heat-resistant igniter composition, characterized by low sensitivity to mechanical stress and increased values of safe current and minimum operating current, which allows it to be used in the manufacture of electric igniters with an increased level of safety during handling . In addition, the proposed formulation does not contain lead belonging to the first hazard class according to GOST 12.1.007-76, and the combustion products of the composition have less toxicity.

The composition is prepared by mechanical mixing according to the technology generally accepted in this production and applied to the bridge of the electric igniter in the form of a drop. To conduct comparative tests, the proposed composition and the composition of the prototype were equipped with electric igniter devices of a standard industrial electric detonator No. 8, equipped with a nichrome bridge (⌀ 30 μm).

Examples of the composition of the prototype (1 ÷ 4) and the claimed composition (5 ÷ 14), as well as the characteristics of these compositions are shown in the table.

As can be seen from the table, the compositions according to the claimed technical solution (5 ÷ 14) have less sensitivity to mechanical stress, greater heat resistance, as well as increased values of safe current and minimum operating current, which characterizes them as safer in the production of electric igniters and their handling . The products of combustion of these compounds are less toxic than the composition of the prototype. Tests for heat resistance showed that the proposed composition and the composition of the prototype can withstand heating at a temperature of 200 ° C for 2 hours without changing its characteristics.

Thus, the developed heat-resistant igniter composition for electric igniters provides increased safety during its manufacture and operation.

Table.
Comparative characteristics of the composition of the prototype (1 ÷ 4) and the claimed composition (5 ÷ 14). Composition Components and Characteristics The content of components (wt.%) And the values of the characteristics for compositions 1 ÷ 14 one 2 3 four 5 6 7 8 9 10 eleven 12 13 fourteen Rodanide Lead 44 fifty Potassium perchlorate fifty 49 60 70 Chromate Lead 6 one Potassium picrate 40 thirty Barium azide 94.0 99.6 94.0 99.6 94.0 99.6 94.0 99.6 94.0 99.6 Methyl cellulose 6.0 0.4 Polyvinyl butyral 6.0 0.4 Nitrocellulose with a nitration rate of 11.0 6.0 0.4 Nitrocellulose with a degree of nitration of 12.5 6.0 0.4 Nitrocellulose with a nitration rate of 14.0 6.0 0.4 Drop height 200 g, response 0%, cm 40 fifty 55 60 80 90 80 90 80 90 80 90 80 90 Drop height 200 g, response 100%, cm 90 one hundred 110 120 180 195 180 195 180 195 180 195 180 195 Working current, A one one one one one one one one one one one one one one Safe current, A 0.3 0.3 0.4 0.4 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Minimum tripping current, A 0.4 0.4 0.5 0.5 0.65 0.6 0.65 0.6 0.65 0.6 0.65 0.6 0.65 0.6 Flash delay time, ms (current 1 A) 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5 3 ÷ 5

Information sources

1. Auxiliary systems of rocket and space technology. Ed. I.V. Tishunina. M.: Mir, 1970, p. 104.

2. US patent No. 3415189 from 12/10/1968

3. P.F. Bubnov, I.P. Sukhov. Means of initiation. M .: Oborongiz, 1945, p. 162.

4. RF patent 2179544 from 02/07/2000, cl. C 06 V 29/02, C 06 C 7/00.

Claims (1)

Heat-resistant igniter composition for electric igniters, characterized in that it contains methylcellulose, polyvinyl butyral or nitrocellulose with a nitration degree of 11.0 to 14.0 and barium azide as the binder in the following ratio, wt.%: Barium azide 94.0-99.6 Binder Rest.