R. Meyer J. Köhler A. Homburg Explosives

Ball Powder
work performed by the explosive, has now been included in the list of
standard tests recommended by the European Commission for the
Standardization of Explosive Testing.
An older comparison scale is “grade strength”, which determines the
particular explosive in standard “straight” dynamite mixtures (the mixtures
contain ungelatinized nitroglycerine in different proportions, sodium
nitrate and wood or vegetable flour (W Dynamites) which gives a
pendulum deflection equal to that given by the test material. The
percentage of nitroglycerine contained in the comparitive explosive is
reported as grade strength.
The grade strength percentage is not a linear indicator of the performance
of the explosive; the performance of a 30% dynamite is more
than half of the performance of a 60% dynamite, because the fueloxidizer
mixtures as well as nitroglycerine also contribute to the gasand
heat-generating explosive reaction.
For comparison of weight strength values with other performance tests
and calculations W Strength.
Ball Powder
Kugelpulver, Globularpulver; poudre sphérique
Ball powder is a propellant with ball-shaped particles, produced by a
special method developed by Mathieson (USA). A concentrated solution
of nitrocellulose in a solvent which is immiscible with water (e.g.,
ethyl acetate) is suspended in water by careful stirring, so that floating
spheres are formed. The solution is warmed at a temperature below
the boiling point of the solvent, and the latter gradually evaporates and
the floating spheres solidify.
Since the spherical shape is unfavorable from internal ballistical considerations
(very degressive), follows, a thorough W Surface Treatment,
the purpose of which is to sheathe the faster-burning core by a
slower-burning shell.
BAM
Bundesanstalt für Materialforschung und -prüfung
Unter den Eichen 87, D-12200 Berlin (www.bam.de)
Federal Institute for Materials Research and Testing (including explosives).
BAM sensitivity tests: W Friction Sensitivity W Heat Sensitivity
and W Impact Sensitivity.
BAM is the German competent Authority for the dangerous goods of
Class 1 and Notified Body in Compliance with EU Directive 93/15.
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