Basic Documentation

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Valve Reference
3. Piping Geometry Factor: Reducing pipe sizes for installation of a smaller than pipe size valves will reduce the effective Cv of the valve.
The greater the pipe reduction, the greater loss of Cv. Using the Adjusted Cvs for Piping Geometry Factors chart, verify that the corrected
Cv, for the valve size selected, meets or exceeds the required Cv calculated in step 2.
Note: 3-way Cvs have already been adjusted.
Adjusted Cvs for Piping Geometry Factors
Pipe Size
Size
2-1/2" 3" 4" 5" 6" 8" 10" 12" 14" 16" 18" 20" 22" 24"
2" 47 38
2-1/2" 125 79
3" 189 149
4" 505 408
5" 947 685
6" 1138 916
8" 2256 1822
10" 3812 3123
12" 5747 4811
14" 8900 7600
16" 11830 10140
18" 16560 14580
20" 20460 18260
6-inch 3-way Assembly at Constant Valve Differential Pressure (corrected for tee loss)