Fritsch PULVERISETTE 5, Руководство по эксплуатации

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The grinding bowls and grinding balls made of zirconium oxide are
resistant to acids - apart from hydrofluoric acid.
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 hardened 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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