Water resistant detonator

Unterwasserzunder = water resistant detonator 369 upsetting tests 42 362 urea nitrate 199 330 346 urethane -> stabilizer 298 US Bureau of Mines 364... 

Determination of Heat Liberated on Explosion with Calorimeter (99-104) Lead Block Expansion Test (Trauzl Test) (104-06) Compression Tests with Small Lead Blocks (106-08) Testing of Detonators, which include Sand Test and Nail Test (108-14) Water Resistance of Electric Detonators (114-15) Testing Burning (Safety) Fuse (115-18) Testing Detonating Fuse (118-19)... 

Accdg to Meyer (Ref 1, p 401), expls used in seismic exploration must be especially water-resistant, very powerful to give expl waves which will be readily detectable over large areas within die limits of the instruments used, and have a high detonation velocity. Blasting Gelatin and Gelatin Dynamites... 

Seismex" is a high strength Ammonia Dynamite which provides the same seismic return as the gelatins but is not as water resistant and its detonation velocity is lower. It should not be exposed to severe conditions (See also Ref 63, p362)... 

F.M. Gel fand V.S. Alipchenko, Ibid 1967, (63/20), 209-12 CA 69, 11865m (1968) [Reasons for a fail are and break in detonations in flooded coal mines were investigated, Expis Ammonit PZhV-20 and Uglenit E-6, coated with water-resistant material, were used in testing. (Compns are not given in CA). It was decided that the excess pressure of CH4 in flooded coal faces was the cause of failure and break of detonation]... 

The following expl compns used in blasting operations are listed in the ref giving their compn, strength (weight and cartridge), detonation velocity, density, water resistance and fume class. For some, detonation pressure is also given... 

Toval. Trade name of ammonia gelatin Dynamite which was distributed in the USA by DuPont. It was DuPont s densest Dynamite, deton vel 4000m/sec at d 1,60g/cc, and was particularly suited for blasting soft to medium hard rock, which requires a high density and water resistant product... 

Tovex. A series of slurry blasting agents (water gels) manufd by DuPont. They consist of an AN slurry, sensitized with monomethylamine nitrate (MMAN), and with a thickener and cross-linking chemical to promote water resistance. Tovex provides increased safety (thru low hazard and initiation sensitivity), high water resistance, good fume characteristics, and a low propensity for sympathetic detonation... 

The intimate mixing of oxidizer and fuel in emulsions give these explosives much higher detonation velocities when compared to ANFO. For example, in 150 mm diameter PVC ANFO has a velocity of about 4000 m/sec, and a sensitized emulsion would have a velocity closer to 6000 m/sec at a density of 1.20-1.25 g/cc. Also, the layer of oil surrounding each oxidizer solution droplet protects the emulsion from extraneous water intrusion and subsequent deterioration of the explosive. Many studies have shown that when mining operations use emulsion explosives rather than ANFO, which has basically no water resistance, the amount of nitrate salts in mine ground water is reduced considerably. This can be a very important factor in today s environmentally conscious mining and explosives industry. 

There is no generally accepted quality classification. Nevertheless, water resistance of an explosive is considered to be satisfactory, acceptable, or poor if the cartridge can still be detonated after 24, 8, or 2 hours respectively. 

USEBLASTING - Great for blasting high detonation rate and comparable in power for 60% ammonia dynamite. Not water resistant. Requires protection from moist boreholes. Powerful and cheap. Must be used in 5" diameter charge or greater. 

The incendivity was decreased by incorporating 8—10% NaF or KF. They were superior to conventional cooling agents, such as NaCl, bicarbonate or oxalate. Expis contg NaF exhibited complete detonation and showed superior water-resistance]... 

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