R. Meyer J. Köhler A. Homburg Explosives

141 Friction Sensitivity
Sensitiveness of friction
This method is the recommended test method in the UN-recommendations
for the transport of dangerous goods and it is standardized as
EN 13631-3 as a so-called Harneonized European Standard.
Procedure
The sample is placed on a roughened 25V25V5 mm porcelain plate,
which is rigidly attached to the sliding carriage of the friction apparatus.
A cylindrical porcelain peg, 10 mm in diameter and 15 mm in
height, with a roughened spherical end (radius of curvature 10 mm), is
placed on top of the sample; the rod is tightly clamped and may be
loaded with different weights with the aid of a loading arm. The load on
the peg may vary
Table 13.
Explosive Pistil Load
kp N
A. Initiating explosives, small machine
lead azide 0.01 0.1
lead styphnate 0.15 1.5
mercury fulminate, gray 0.3 3
mercury fulminate, white 0.5 5
tetrazene 0.8 8
B. Secondary explosive materials, large
machine
PETN (Nitropenta) 6 60
RDX (Hexogen) 12 120
HMX (Octogen) 12 120
Tetryl 36 353
C. Industrial explosives, large machine
blasting gelatin 8 80
Gelignite, 60 % nitroglycerine 12 120
Ammongelit, 38 % nitroglycol 24 240
(Gelatins with a low content of nitroglycerine or nitroglycol, powderform
explosives, slurries and permitted explosives, ammonium nitrate;
dinitrobenzene; nitroglycol; nitroglycerine, nitrocellulose up to
13.4 % N, picric acid and TNT do not react up to a pistil load of
36 kp.)
between 0.01 and 1 kp in a small apparatus and between 0.5 and
36 kp in a large apparatus. The porcelain plate moves forward and
back under the porcelain peg; the stroke length is 10 mm in each
direction. The two ends of the peg will serve for two trials and the two
friction surfaces of the plate will serve for three trials each.