Transmission of Detonation at a Distance

Transmission de dytonatiqn k distance (Transmission of Detonation at a Distance), known as Aptitude k traosmettre la detonation a distance (Ability to Transmit the Detonation at a Distance). See Ref 24, E140-L. Same as Detonation by Influence, Sympathetic Detonation or Gap Test... 

Detonation by Influence or Sympathetic Detonation Tests (Transmission of Detonation at a Distance Test) (Aptitude a transmettre la detonation a distance, Essai or Coefficient de self-excitation, Essai, in Fr) (Detonationsiibertragung Probe ox Schlagweite Probe, in Ger) (Determinacion de la sensibilidad a la iniciacion por simp ana, in Span) (Distanxa di eaplosione persimpatia, prova, in Ital) include the following methods Booster Sensitivity Test(qy) b)Four-Cartridge Test]Sce PATR 2510(PB 1612 i(1958),p Ger 521... 

Transmission de la detonation d distance (Transmission of Detonation at a Distance), also known as Coefficient de self-excitation (Coefficient of Self-excitation) or Aptitude b tronsmettre lo ddtonation b distance (Capability, to Transmit the Detonation at a Distance). This test is known in the USA as Gap Test, Sympathetic Deto-notion Test or Detonation by Influence Test. The French modification of the test described by M dard (Ref 8, pp 342-44) was earlier described by Dutour (Ref 6). This test is described in Vol 3 of Encycl, p C3SX) as Coefficient de Self-excitation (CSE) and gap values for several expls at different densities are given... 

Type I—dynamites and rock explosives. The chief ingredients of the latter are ammonium nitrate, nitroglycerine and TNT. Their rate of detonation at a density of 1.1 is about 3800m/sec, their transmission distance 6 cm. 

Detonation, Sympathetic Detonation. Flash over means the transmission of detonation from a cartridge to another one in line. Explosives with extremely high flash over tendency can be initiated by the shock wave from one charged borehole to the next one, even at large distances (- Ditching Dynamite). 

One can also study the influence of the mass of the donor charge on the distance at which complete transmission of detonation to a given acceptor charge may occur. Then the tests are conducted in such a manner that the distances dso or dioo at which transmission of detonation occms in 50% or 100% cases, respectively, are determined for each mass of the donor charge. On the basis of the data, the dependence of the distance ( 50 or if 100) upon the mass of the explosive charge (Mj) as shown in Figure 2.30 m be obtained. 

The donor and acceptor charges, separated by an air gap, are placed in a coal-cement tube stemmed at both ends. By decreasing or increasing the distance between the charges, one can determine the maximum distance at vdiich in three consecutive trials the complete transmission of detonation is achieved. 

The method is based on the determination of the maximum distance between the donor and the acceptor charge, placed on a flat steel plate, at which complete transmission of detonation from the donor to the acceptor charge is obtained in three consecutive trials. 

The maximum distance at which the complete transmission of detonation is observed in three consecutive trials is report as a test result. 

According to Marshall (Ref 1), a simple method of determining the distance of transmission, is to set out a row of amall cartridges at increasing distances apart and to determine how many of them explode when the end cartridge is detonated... 

Detonation, Shock Transmission from Explosive to Metal Plate. Accdg to Cook (Ref 3, p 1H)> R.W. Goranson is credited with suggesting that it is possible to determine the p(x), W(x) and p(x) distribution in the detonation wave by studying the characteristics of the shock wave transmitted from the explosive into a thin metal plate in shock loading of the plate by a detonation wave. In this theory, when a plane detonation wave strikes a metal plate at normal incidence, a shock wave is transmitted into the plate and another is reflected back into the incident wave such. as to give a pressure-distance profile like that illustrated in Fig 5.17 [reproduced by Cook from the paper of Walsh Christian (Ref 1)]. 

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