FRITSCH PULVERISETTE 7 classic line - Manual (Page 34)

6.4.7 Wet grinding (grinding in a suspension)
DANGER!
Explosion hazard! Ignition hazard!
The device is not explosion-protected. If flammable liquids
are used, make sure that the heat developing in the
grinding bowl does not reach the solvent's boiling point.
Program appropriate cooling phases. If the vapour pressure
is too high, vapours may escape and ignite.
If it can be avoided, we recommend using non-flammable
liquids or liquids with a high boiling point. The boiling point
should be above 80 °C and above 100 °C for a long grinding
duration.
During the transition to grinding in suspension, you can add a liquid aux-
iliary agent with high boiling point and low vapour pressure, e.g. water,
white spirits (boiling point 100 - 140°C), or alcohols with a high boiling
point (e.g. isopropanol)
We recommend that you only use so much liquid that the suspension
has the same consistency as motor oil. With this viscosity the best results
can be achieved in most cases.
6.5 Clamping the grinding bowls
6.5.1 Clamping with the spindle clamping device (5)
Carry out the following checks before clamping the grinding bowls:
n Check the cork disc for damage
Replace the cork discs if they have been pressed flat
n The Teflon flat seal (for the seal between the lid and the bowl)
should not be damaged or soiled.
Replace heavily deformed Teflon flat seals.
n Check the rubber disc for damage!
Replace rubber discs that have been pressed flat and are protruding
laterally from the pressure piece.
n The end faces of the counter plates and the clamping bracket should
not be dirty.
n The lid and bowl surfaces that contact the Teflon flat seal must be
clean.
Using the device
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