FRITSCH PULVERISETTE 14 - Manual (Page 35)

6.10 Grinding with the impact rotor element
For the article numbers, please refer to our homepage or the spare parts
catalogue.
1 Motor mounting flange
2 Motor shaft
3 Labyrinth disk
4 O-ring, 94x3
5 O-ring, 88x3
6 Collecting vessel
7 Rotor
8 Impact bar (optional)
9 O-Ring 90x3 for impact element (optional)
10 Sieve ring
11 Lid seal
12 Collecting vessel lid
To carry out milling with a process similar to that of a cross beater mill,
there is an optional insert with impact bar (8) and an outer sieve ring
(10) with 1.0 mm trapezoidal perforation.
The rotor (7) with 8 teeth operates directly next to the impact bar (8).
This increases the shear stress on the source material. This provides for
faster coarse grinding of brittle source material. Additionally, the tem-
perature load on the source material for fine milling is significantly
lower.
During milling tests the best results were achieved with an 8-rib rotor (7)
and 1.0 mm sieve ring (10). However, any other rotor can be employed,
so that it is possible to use a rotor that is already on hand. If an existing
rotor will be used, only the impact bar and a matching sieve ring need to
be ordered.
The standard sieve rings cannot be used.
The handling of the impact rotor insert is the same as for the standard
grinding elements (see Ä Chapter 6.3 ‘Installing the grinding elements’
on page 27, Ä Chapter 6.5 ‘Removing the grinding elements’ on page 29
and Ä Chapter 6.4 ‘Conducting a grinding operation’ on page 28). The
sieve ring is just replaced with the impact bar (8) and outer sieve ring
(10).
The O-ring (9) serves to seal off the sieve ring (10) from the lid (12) of the
collecting vessel. First, the sieve ring (10) is placed over the impact bar
(8) and then the O-ring (9) is pressed into the groove.
In addition to the 8-blade rotor, the 12- or 24-rib rotors may also be
employed. For the order numbers of the different sieve rings, please
refer to the spare parts drawing.
Using the device
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