FRITSCH PULVERISETTE 7 premium line - Manual (Page 34)

5.2.3 Number of balls per grinding bowl (independent of the material quantity)
A higher number of balls will reduce the grinding duration and the
grinding results will be within a smaller grain size range.
The number of balls should be complied with to avoid unnecessary wear.
Ball diameter (mm) Grinding bowl
volume (ml)
20 45 80
20 Number of balls (St) - - 5
15 Number of balls (St) - 7 10
10 Number of balls (St) 10 18 25-30
5 Number of balls (St) 80 180 250
Ball with a diameter of 3 mm and smaller
Material Grinding bowl
volume (ml)
20 45 80
Zirconium oxide Amount of balls
(grams)
30 70 100
Tempered steel Amount of balls
(grams)
40 90 150
Tungsten carbide Amount of balls
(grams)
80 200 300
Using the device
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