Calculating Ball Mill Motor & Ball Mill Size (Metric)  
                             
          Model Input   Model Output              
Feed Metric TPH   Total work required to produce the product, hp-hrs/metric ton  
P80 µm   Power required, HP  
F80 µm   Power required, kW  
Work index Kwh/metric ton   Net diameter of mill (foot)  
Mill Diameter inside shell (foot)   Length of Mill required to draw the desired power (foot)  
Volume occupied by the charge (%Loading) 40                  
%Critical Speed 68     This sizing formula is also good for Rod Mills  
        Factor A Reference Table 1              
        Factor B Reference Table 2              
        Factor C Reference Table 3              
                             
  Reference table 1     Reference table 2   Reference table 3  
  Diameter     Factor B   %Critical
Speed 		Factor C  
  Dia. Inside
Shell Liners 		Factor A     Ball Mill Rod Mill    
    %Loading Dry Diaphragm  Wet Diaphragm  Wet Overflow Dry Diaphragm  Wet Diaphragm  Wet Overflow   60 0.134  
8'0" 32
20 4.30 3.87 3.44 4.73 4.25 3.78
61 0.137
8'6" 37.3
22 4.57 4.12 3.66 5.04 4.54 4.03
0.14
9'0" 43.1
24 4.80 4.32 3.84 5.27 4.75 4.22
0.143
9'6" 49.6
26 5.07 4.57 4.06 5.58 5.02 4.47
0.146
10'0" 56.1
28 5.31 4.77 4.24 5.82 5.24 4.66
0.149
10'6" 63.5
30 5.53 4.97 4.42 6.08 5.47 4.86
0.1521
11'0" 71.1
32 5.71 5.14 4.57 6.28 5.65 5.02
0.1552
11'6" 79.3
34 5.90 5.32 4.72 6.48 5.83 5.19
0.1583
12'0" 88.4
36 6.05 5.45 4.84 6.67 6.00 5.33
0.1625
12'6" 97.5
38 6.16 5.55 4.93 6.78 6.10 5.42
0.1657
13'0" 108
40 6.27 5.65 5.02 6.90 6.21 5.52
0.169
13'6" 118.5
42 6.34 5.70 5.08
0.1724
14'0" 130
44 6.41 5.77 5.13
0.176
14'6" 141.5
46 6.46 5.82 5.17
0.1798
15'0" 154.5
48 6.49 5.84 5.19
0.1838
15'6" 167.2
50 6.50 5.85 5.20
0.1878
16'0" 181.5
0.1918
16'6" 196
0.1958
17'0" 211.2
0.1999
17'6" 226.7
0.204
18'0" 243.6
0.2081
18'6" 260.5
0.2124
19'0" 278.9
0.2166
19'6" 297.8
0.2208
20'0" 317.1
0.2251
0.2294
                        0.2337  
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