Wednesday, December 16, 2015

BLACKOUTS GRAPHITE GRENADES


Explosive Potential of Graphite Dust
Combustible dust is identified as, "Any finely divided solid material that is 420 microns or smaller in diameter (material passing a U.S. No. 40 Standard Sieve) and presents a fire or explosion hazard when dispersed and ignited in air."² The elements of fire include fuel, oxygen and ignition. A dust fire or deflagration occurs when sufficient concentrations of fine particulates are suspended in air and then exposed to a source of ignition such as a spark or welding igniter. This ultimately results in the igniting or combustion of the dust.

THE REST OF THE GRENADE COMPOSITION: 
High speed automatic mechanical pressing is commonly used to volumetricaHy load small quantities of primary explosives into blasting caps and detonators and to make small explosive components. Primary explosives may be mixed with graphite to improve flow and antistatic properties, or may be desensitized with waxes, stearates, or polymeric compounds. Secondary explosives and explosive mixtures may be pressed to form booster pellets or to load components directiy as in the case of armor-penetrating projectiles. Where the explosive is too sensitive in its pure crystalline state to permit press loading or lacks the requited mechanical properties in its compressed state for subsequent use, it is coated with polymeric materials such as polystyrene and polybutadiene, to form mol ding powders, often referred to as plastic-bonded explosives. Desensitization is obtained when the explosive crystals are thoroughly and uniformly coated. A typical procedure for making PBX-type explosives involves making a lacquer of a solution of the organic polymer in a solvent, eg, ethylacetate, and a dding it to a water slurry of the explosive. The solvent is distilled off under vacuum while the mix is agitated, precipitating the polymer on the explosive. The coated explosive forms small agglomerates as the solvent removal process continues. It is filtered, washed, and vacuum dried to form a free-fiowing, dustiess, high density powder. Bi- or trimodal size distributions of spherical shaped explosive particles are often used to improve the flow characteristics and packing density of the mol ding powder. Antistatic agents (qv) such as carbon black may be added to prevent dust explosions. In another coating technique, the requited amount of low melting wax is added to a water slurry of the explosive at a temperature high enough to melt the wax. After agitation to distribute the wax on the crystals, the temperature is lowered, the water decanted, and the remaining mass filtered and dried

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