Retsch Mixer Mill MM 500 control, Руководство пользователя

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Operating the Device
58
Component Function
ÖR Side for locking wheel This side is for unscrewing the locking wheels on the
grinding jar supports.
6.5.1 Grinding Jar Identification
All grinding jars and the matching grinding jar covers can be identified by a labeling field on the
outside. The labeling field provides information on size and material of the grinding jar.
6.5.2 Ball Sizes and Speeds
A very large amount of energy is applied to the sample material on the MM 500 control. This
large amount of energy also affects the grinding jars and the grinding balls.
Depending on the grinding jar size , the following recommendations therefore apply to the
sample volume and ball sizes that can be used.
6.5.3 Recommended maximum ball sizes
Grinding jar size Ball size
50 ml 25 mm
80 ml 25 mm
125 ml 20 mm
6.5.4 Recommended Grinding Jar Filling
In addition to device settings, the fill level of the grinding jars is crucial for the success of
grinding in the Mixer Mill.
When grinding bulk materials, a grinding jar filling should
consist roughly of one third sample material and one third ball volume. The remaining
third is the empty grinding jar volume that the balls need in order to move. Please pay attention
to the maximum permitted ball size for the material in question.
If an increase in volume or decrease in volume is to be expected during grinding, the sample
volume can be adjusted in line with the range set out in the table. For example in the case of
voluminous sample material such as wool, leaves, grasses etc., an initial material filling of 70
–
80 % is necessary.
The ball filling should comprise 60 % of the grinding jar volume for wet grinding with grinding
balls < 3 mm. As with dry grinding, the sample material should fill one third of the grinding jar
volume. Wet grinding should be conducted in such a way that the mixture of grinding balls,
sample material and liquid achieves a viscous consistency. If the mixture is too viscous, the
grinding balls do not move sufficiently. If it is not viscous enough, the grinding results will be
poorer and there will be increased wear to the grinding balls and grinding jars.