Vojtech Pelikan
Abstract: The electrical properties of bridgeless fuseheads were examined. A conducting composition conducting composition based on the mixture lead styphnate, Viton binder and conductive admixture was used as the fusehead as the fusehead priming mixture. Several types of conducting admixtures, namely two types of natural finely milled graphite and special conducting carbon black, of varying particle size and origin, were used. To produce fuseheads the standard dipping technology for application of the pyrotechnic mixture was used. Fuseheads equipped with a safety shroud and leading wires were installed in a standard aluminum body No. 8 detonator to test the electrical and firing characteristics and determine how these fuseheads will affect the detonator’s properties in particular regarding reaction time. The measurements further included determination of electric sensitivity (All-fire energy) and resistance.
It was found that for production of this type of fusehead is possible to use standard dipping technology without significant change in the technological process, but the presence of binder in the pyrotechnic composition has a considerable influence on the electrical properties. Determination of the reaction times of detonators showed that is possible to reach very short reaction times less than 1ms. This is approx. 20 times less compared with a detonator (or fusehead) equipped with a standard bridge wire fusehead. This could be advantageous for the many applications where a fast response of the electro-explosive system is required together with low cost and ease of use. Typical of such applications are firework displays and special pyrotechnic effects.
Keywords: conducting composition, initiator, lead styphnate, electric detonator, fusehead
Ref: JPyro, Issue 24, 2006, pp3-10
(J24_3)
© Journal of Pyrotechnics and CarnDu Ltd
