R. Meyer J. Köhler A. Homburg Explosives

Free-flowing Explosives
tected sites for high-speed measuring equipment) that a desired
wedge of projectile casing fragments can be observed. The fragment
velocities are determined by shadow photographs, using flash bulbs,
and rotating drum cameras, each behind three slits. The drum cameras
have a writing speed of 30 meters per second.
Free-flowing Explosives
Rieselfähige Sprengstoffe; explosifs pulvérulents
Non-cartridged commercial explosives which can be poured into boreholes,
mostly ammonium nitrate explosives containing anticaking
agents. When ammonium nitrate became commercially available as
W Prills (porous pellets), W ANFO blasting agents could also be utilized
in the free-flowing form; W also Pellets.
Freezing of Nitroglycerine – based Explosives
Gefrieren von Nitroglycerin-Sprengstoffen;
congélation d’explosifs à base de la nitroglycerine
Nitroglycerine may freeze at +10 °C. The frozen cartridges are unsafe
to handle, and improvised thawing operations are risky. Freezing is
prevented by adding nitroglycol to the nitroglycerine.
Friction Sensitivity
Reibempfindlichkeit; sensitiveness to friction; sensibilité au frottement
The sensitivity to friction can be determinated by rubbing a small
quantity of the explosive in an unglazed porcelain mortar. The sample
being tested is compared with a standard specimen.
In the USA, the friction procedure is made by the friction pendulum
test:
A 0.7-g sample of explosive, 5–100 mesh, is exposed to the action of
a steel or fiber shoe swinging as a pendulum at the end of a long steel
rod. The behavior of the sample is described
qualitatively, i.e., the most energetic reaction is explosion, and in
decreasing order: snaps, cracks, and unaffected.
An improved method, developed by the Bundesanstalt für Materialforschung
und -prüfung (W BAM)*), Germany, yields reproducible
numerical values.
* Koenen and Ide, Explosivstoffe, Vol. 9 pp. 4 and 10 (1961).
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