FRITSCH PULVERISETTE 14 - Manual (Page 25)

When feeding the material, the inner funnel can be removed.
This rotor is also suitable for pre-crushing or rough comminution.
24-rib rotor
The rotor with 24 ribs (order no. 44.4240.10) enables fast fine grinding
for all materials with a particle feed size < 5 mm (largest length).
NOTICE!
The 24-rib rotor should not be used for grinding plastics
containing carbon or glass fibres. There is a risk of breaking
a tooth.
When using the conversion kit (order no. 14.3510.00) or the cyclone sep-
arator (14.3740.00), this rotor achieves the highest air flow rate. By
doing so, it accelerates grinding, improves cooling and helps to protect
heat-sensitive grinding stock.
NOTICE!
When the rotors are badly worn, there is a risk of the teeth
breaking off and causing further damage to the device.
® Replace worn rotors in good time!
6.2 Sieve ring
The final fineness of the source material is determined by the choice of
sieve ring.
For the sieve ring sizes available, see the service manual.
Typically, the final fineness of the source material is smaller than the per-
foration diameter set by the sieve ring. In normal cases, use the sieve
ring with trapezoidal perforation with the direction arrow on it pointing
upwards↑.
With this setting, some particles in the source material may be longer
than as specified by the perforation diameter.
If a large share of fine particles is desired, install the sieve ring with the
direction arrow pointed downwards ↓. This lowers the throughput.
As a general rule, approx. 2/3 of the feeding amount is milled finer than
1/2 of the perforation diameter.
NOTICE!
When milling without a sieve ring, a spacer ring
(44.1110.10) has to be used so that the distance between
lid and rotor is maintained.
Using the device
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