3 calculated weight of a ball, 2 filling quantities of grinding bowls, Using the device – FRITSCH PULVERISETTE 7 classic line User Manual

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Grinding bowl /
Useful capacity (material to be

ground)

12 ml
0.5 - 5 ml

45 ml
3 - 20 ml

Stainless steel /
Tempered steel

30 g

90 g

Hardmetal tungsten carbide

50 g

200 g

6.1.3 Calculated weight of a ball

Ball diameter in mm

5

10

15

Material

Density in g/cm

3

Calculated weight of a ball in g

Agate

2.65

0.17

1.39

4.68

Silicon nitride

3.25

0.20

1.7

5.48

Sintered corundum

3.9

0.25

1.99

6.72

Zirconium oxide

5.7

0.37

2.98

10.07

Stainless steel

7.8

0.51

4.08

13.78

Tempered steel

7.9

0.52

4.14

13.96

Tungsten carbide

14.9

0.96

7.70

25.98

To determine the weight of the required balls, the "calculated weight of

a ball" is multiplied by the "number" of balls required.
Example: A 45 ml agate bowl is to be filled with 185 agate balls with a

diameter of 5 mm.
Calculation: 0.17 g * 185 pcs » 31.45 g
31.45 g of grinding balls can be weighed and inserted in the grinding

bowl, thus avoiding the time required for counting the balls.

6.2 Filling quantities of grinding bowls

NOTICE!
Never operate the mill without grinding stock! This can

cause damage to the grinding balls and grinding bowls.

Using the device

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