FRITSCH PULVERISETTE 14 - Manual (Page 9)

2.2.1 Operating principle
The fast comminution capability of the PULVERISETTE 14 is due to the
extremely high speed of the rotor, which is made of stainless, tempered
steel. With a rotational speed of up to 92 m sec -1 , the impact energy lies
in the range of pin mills, known for their high grinding capacity. Addition-
ally, the sharp-edged teeth of the rotor work in combination with the
installed sieve to grind the sample by shearing - similar to high speed
cutting mills. After passing through the sieve, the ground sample is col-
lected in a stainless collecting vessel or a filter sack. It is also possible to
use a sample exhaust system with cyclone separator.
The source material is fed through a funnel into the grinding chamber
and accelerated outwards radially by the high speed of the rotor. There,
the material is caught by the impact rotor, ground, and then discharged
through the sieve ring into the collecting vessel at a defined particle feed
size.
For larger amounts or for materials more sensitive to heat, a collecting
vessel with a flange-mounted filter sack (optional conversion kit) or the
cyclone separator is used as the sample exhaust system. Here, the
sample is cooled by a current of air from the turbine-like action of the
rotor and then directly discharged.
To ensure continuous flow of the sample, the electromagnetic vibratory
feeder LABORETTE 24 is connected to the PULVERISETTE 14 and the free
end of the channel is placed over the input funnel of the PULVERISETTE
14. The feed rate can be regulated by the user to always feed the right
amount of sample for optimal comminution. If the amount of source
material is too large, the feeder is automatically switched off and then
on again.
2.2.2 Speed control
With the (+) or (-) keys, the speed of the rotor can be preselected in
steps of 1000 rpm in the range 6000-20000 rpm and in this way be opti-
mally adapted to the requirements of the grinding of the samples. The
speed is readjusted for each load.
2.3 Obligations of the operator
Before using the of the PULVERISETTE 14, this manual is to be carefully
read and understood. The use of the of the PULVERISETTE 14 requires
technical knowledge; only commercial use is permitted.
The operating personnel must be familiar with the content of the oper-
ating manual. For this reason, it is very important that these persons
actually receive the present operating manual. Ensure that the operating
manual is always near the device.
Safety information and use
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