Retsch DM 400 - Manual (Page 10)

Safety instructions and use
10
2.2 Intended use
The DM400 is a disc mill for batch or continuous fine grinding of hard
brittle to medium hard solids from the areas of mining and metallurgy,
geology and mineralogy and the glass and ceramics industry.
The maximum feed size is 20 mm edge length; the achievable final
fineness level depending on the gap width set is approx. 12 mm (larg-
est gap width) and 0.05 mm (smallest gap width).
The material throughput of the disc mill lies in the range of 20 to 150
kg/h. This depends on the setting of the outlet gap and the bulk
weight and grinding conduct of the sample.
2.2.1 Operating principle
The grinding of the material sample takes place in a grinding
chamber which is dustproof to the outside and in which two
coarsely toothed grinding discs operate against each other.
The moving grinding disc is driven by a powerful, slow running
gear motor.
The sample material is filled through a lockable hopper into the
centre of the upright grinding disc and, after being ground by
compression and shear stress, escapes through the gap be-
tween the two discs. The gap width determines the mean parti-
cle size of the sample material. The grinding gap can be set to
an accuracy of 0.05 mm using the plus/minus buttons on the
control panel. The gap width can be read off the display (1).
When grinding batches, the sample material is collected in a
sample material container placed in the device (volume: 2l).
The closed design prevents dust escaping. A dust extraction
device may additionally be connected. To clean, the front hous-
ing is opened sideways - the grinding chamber is then freely
accessible.
2.3 Duties of the operating company
This Manual should be read and understood before using the DM400.
Use of the DM400 demands expert knowledge and should be limited
to commercial users.
Operating personnel must be familiar with the contents of the Operat-
ing Manual. It is therefore very important for this Operating Manual to
be actually handed to these persons. It must be ensured that the
Operating Manual always remains with the device.
The DM400 may be used exclusively within the possible uses set out
in this Manual and within the specified regulations in this Manual. In
the event of contravention or incorrect use, the customer assumes full