CS263506B1 - Delay of the millisecond type - Google Patents

Abstract

The solution relates to millisecond-type retarding compositions containing ferroalcochrome as a combustible and lead oxide (Pb2O3) as an oxidizer. The aim of the solution is to reduce the sensitivity of retarding compositions based on this basis to mechanical stimuli, especially to friction and impact, which is achieved by adding 0.1 to 5 weight percent magnesium stearate (036H70θ2Μβ) to the retarding composition.

Description

The invention relates to a millisecond delay composition, in particular to a gas-free delay composition for ferrosilicochrome and lead-lead oxide mining detonators.

For accurate timing of the individual stages of the series, millisecond detonators, where the transfer of thermal energy is effected by the reaction of oxidant and combustible material, the requirement for low-gas flow during combustion is a significant factor. Perfect homogeneity of the composition is required for uniformity of combustion. To meet this requirement, it is necessary to use the individual components of the composition in a very fine state, but after homogenization such composition is completely unsuitable for the bulk dosing necessary for mass production of the final product, i.e. timed detonators. Therefore, it is necessary to compact and homogenize the homogenized composition obtained in a very fine form. The sieving then provides the necessary uniform grain size which allows repeatability and correct dosing.

During the described processes and subsequent operations required to produce the final product containing other components such as explosives and explosives, the delay components are subjected to mechanical stimuli, in particular friction, which causes the delay component to burn. Burning; during production, it degrades production equipment, increases production effort by difficult cleaning of production equipment, tools, aids, etc. The ignition of the delay composition also has an adverse impact on the final phase of the production of electric detonators, where technological explosions may be endangered by the safety and health of workers.

The object of the invention is to minimize the risk in the manufacture of electrical timed detonators. This is achieved with a delay of 263 506

- 2 millisecond type compositions consisting of lead-oxide as oxidant and ferrosilicochrome-based flammable substance, characterized in that 0.1 to 5% by weight of the metal salt of stearic acid is added to the retardant.

The main advantage of the solution according to the invention is a considerable reduction in the sensitivity of the delay composition to mechanical stimuli, in particular friction, without appreciably affecting the regularity in the burn rate of the delay composition. In addition, there is an increase in the safety of work in the production of millisecond-type timed detonators, as well as an economic cost benefit. Decreasing the sensitivity of the delay compositions to friction creates conditions for the application of automation in the production of delay compositions in various operations of the technological process such as compaction, crushing, screening, eventually dosing in an unconventional manner.

The activation tests are performed by applying to a certain weight unit of the composition, poured onto a ceramic plate, a ceramic pin under pressure, which increases in size until the time of activation of the compound. The pressure in kilograms is then a measure of the friction resistance of the composition. In a particular case, when evaluating a sample composition according to the invention, 1% of magnesium stearate homogenized in a millisecond delay composition was achieved at a pressure of 24 kg, compared to an untreated composition where activation was already at 6 kg. In this case, the friction sensitivity was reduced four times with very little phlegmatizer.

Example:

To 20 kg of the delay composition containing the homogenized components of ferrosilicochrome and lead oxide (Pb? O?) 0.2 kg of magnesium stearate (C? GH?? OgMg) was added and homogenization was performed. In another variant, 1 kg of magnesium stearate (C ^HgClgM Mg) is added per 43 kg of ferrosilicochrome, homogenized, and then lead-oxide (Pb ^O O) of 57 kg is added.

Claims (1)

SUBJECT OF THE INVENTION A millisecond type delay component consisting of lead-lead oxide (Pb 2 O 4) as the oxidant and a ferrosilicochrome-based combustible, characterized in that 0.1 to 5 weight percent of a metal salt of stearic acid, eg magnesium stearate, is added to the delay composition. (C 18 H 18 C 18 Cl 9).