Calculating Motor & Mill Size  (Short Tons)
          Model Input   Model Output            
      Feed STPH   Total work required to produce the product, hp-hrs/short ton
      P80 µm   Power required, HP        
      F80 µm   Power required, kW        
Work index Kwh/short 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  40 (%Loading)              
%Critical Speed 68                
        Factor A Reference Table 1 This sizing formula is also good for Rod Mills
        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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