FRITSCH PULVERISETTE 6 classic line - Manual (Page 37)

6.7 Grinding duration
WARNING!
Burn hazard!
Grinding bowls can get very hot after long grinding dura-
tions. Wear protective gloves for removal after grinding or
during the grinding breaks.
Depending on the application, the grinding duration should be adapted
to the development of heat in the bowls. The temperature inside the
bowls is 20 - 30 °C warmer than the outer casing temperature.
CAUTION!
The maximum temperature of the grinding bowl outer
casing is 100 - 110 °C (agate, max. 70 - 80 °C).
The grinding duration is therefore based on the maximum
bowl temperature. The grinding duration at which the tem-
perature is not exceeded depends on the material, ball, and
speed. For this reason, the user should determine it
through experimentation.
Reference value
When grinding at high speeds and with large bowls, a grinding duration
of one hour (depending on the temperature) should not be exceeded.
Then allow the unit to cool down for half an hour to one hour.
NOTICE!
– Observe the warming up of the grinding stock.
– A longer running time may require pause times for
cooling down.
– Check that the tensioning device is firmly connected
when switching on again after a cooling-down phase.
NOTICE!
If bowls are removed during a grinding pause, check that
they fit correctly before the device is switched back on.
The extent to which the heating up of grinding stock needs
to be observed depends of course on the sample used in
each individual case. Note® A longer running time may also
require a longer pause time for cooling down.
Using the device
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