Ignition means

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Ignition agents, typically 1.4 substances and objects according to ADR , with a low risk of explosion - effects are limited to the package

Detonators from blasting technology and igniters from pyrotechnics are aids that are used to trigger an explosion . They provide the necessary initial energy for the chemical reactions of explosive substances .

One differentiates:

  • Explosive detonators intended for explosive charges and containing explosive substances. The ignition of an explosive starts the detonation .
  • Initial detonators are detonators that go into detonation on pyrotechnic ignition, all other detonators only detonate when they are excited by a detonation
  • Pyrotechnic ignition devices that do not provide sufficient energy for detonation.

The simplest thermal ignition means are the match and the lighter , the simplest electrical ignition means are a piezo generator or a crank inductor .

In contrast to electrical ignition , the direct use of detonators is referred to as pyrotechnic ignition - due to the danger, the direct use of detonators is only common in military explosives ( bombs and the like).

Definition of terms igniting - igniting

Under lighting is the production of a burn-up (deflagration) , including ignition , however, triggering a detonation . Both forms are summarized under the term explosion . The difference between the two forms lies in whether the ignition process in the material exceeds the speed of sound or not. In the first case, a shock wave occurs, the detonation wave , in which the flame front coincides with the shock front, whereby the extremely high initial energy in the explosive is overcome, which sets the chemical process in motion that releases the detonation energy.

An ignition means cannot ignite explosives , but pyrotechnic charges or detonators containing an initial charge can. The explosive detonators and the primers detonate themselves and can therefore detonate explosives.

The distinction between igniter and igniter is specified in the ADR , where the difference has a decisive influence on the dangerous goods class of an igniter as well as the permitted transport together with explosives. In common parlance, mostly only “ignition means” is used for all types.

Detonators of blasting technology

The ignition means include detonators and detonators , which generate the necessary pressure and ignition temperature.

  • Detonating cords contain an explosive substancesuch as pentaerythritol tetranitrate (PETN) and transfer the detonation of a detonator capsule to various explosive charges at a speed of up to 8400 m / s.
  • In most of the technical applications of explosives, electric detonators are used today. Non-electric detonators are also used in the demolition.

Igniter in the fireworks shop

There are three types of ignition in fireworks :

  • Manual ignition: direct ignition with an open flame . Today this type of ignition is only used in small fireworks such as fireworks rockets for private use, light sources and the like. In commercial fireworks, the method is only used in exceptional cases and by specialists with great experience and under special safety measures because of the risks posed by the proximity to the burn site.
    Typical ignition devices for hand ignition are:
    • Ignition light - a special magnesium compound that is water-resistant when burned
    • Fuse lighter - a cardboard tube with a reaming head
    • Abreißanzünder - these are usually in a product integrated
  • Ignition by delay device: In fact, all commercially available fireworks effects are delayed by at least a few seconds so that the person who ignites them can leave. The application of delays to a pyrotechnic object and the combination of several effects is known as enticing . Only the certified pyrotechnician is permitted. Enticing forms the basis of classic fireworks by combining the effects into a controlled process, which then results in the actual fireworks. Be used:
    • Fuses that transmit the ignition to the object
    • Retarders , either as a prefabricated product with delay times of 2, 3 or 4 seconds, or by means of slow- burning fuses (time fuse, fuse wire, China fuse, swamp fuse)
    • Bundled effects are pyrotechnic effects in which several individual effects are created ex works. The most famous representatives are the cakeboxes or Roman lights with several shots.
  • Electric ignition: The electric igniter (bridge igniter ) has also replaced the classic methods in commercial fireworks . The preparation is limited to the wiring , and the actual shot is done with a blasting machine , or even an ignition computer . Enticing is generally no longer necessary, each effect has its own electric igniter and is controlled by the ignition system to a tenth of a second. For this purpose, modernly equipped pyrotechnicians have blasting machines with several dozen or hundreds of individual ignition lines . The fireworks can then be set off from a distance.

According to ADR, igniters are generally assigned to hazard class 1.4G pyrotechnic substance or object with pyrotechnic substance with a low risk of explosion .

literature

  • August Eschenbacher: Fireworks or the manufacture of fireworks. A representation of the entire pyrotechnics. Survival Press, Radolfzell 2001, ISBN 3-8311-2743-3
  • G. Lathan: Explosives and detonators in ore mining. Fachbuchverlag, Leipzig 1953.
  • C. Beyling, K. Drekopf: Explosives and detonators with special consideration of the work of explosives underground. Springer Verlag, Berlin Heidelberg 1936.
  • Fritz Heise: Explosives and ignition of the high explosive shots. With special consideration of the danger of firedamp and coal dust in coal mines, published by Julius Springer, Berlin 1904.

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