FRITSCH PULVERISETTE 4 classic line - Manual (Page 26)

Normally choose a grinding bowl and grinding balls that are made of the
same material.
Exception: Tungsten carbide balls (<20 mm) may be temporarily (a few
minutes) combined with grinding bowls made of tempered steel.
6.1.1 Size of the grinding balls
Type of feed material Suitable ball diameter
Hard samples with a maximum feed size of 10 mm 30 mm or 40 mm
Average feed size of < 5 mm 20 mm
Fine material < 0.5 mm 10 mm or 5 mm
Homogenisation of dry or liquid samples 10 mm
Homogenisation of viscous samples 20 mm
These are reference values: The size of bowls and grinding balls may
need to be determined through experimentation.
NOTICE!
It is not advisable to mix balls of different diameters. (If
balls with different diameters are used, increased wear to
the balls is to be expected.)
NOTICE!
Balls with a diameter of 40 mm are rarely used for grinding,
because this ball size can cause damage to the grinding
bowl fast if the grinding duration is too long. Only use
grinding balls of this diameter for brief grinding durations.
Using the device
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