The Gustaf Fagerberg calculating tool offers a fast and easy way to estimate kv-values for control valves.
There are calculations for three different common medias: Water, saturated steam and air. By putting in the flow rate, up- and downstream pressure and temperature (for water and air), the program estimates the kv-value.
The kv-estimation is a useful guide line which gives an idea of the correct valve type and –size, and/or to determine if an installed valve has the required capacity.
The results are calculated from basic and commonly known formulas for water, saturated steam and air, the two latter both with critical and non critical pressure drop,
Note the calculations are basic and the results shall only be used as guide lines.
The flow rate is for water entered in m/h or kg/h, for saturated steam in kg/h and for air in Nm³/h. The unit for up- and downstream pressure is bar a, and for temperature °C.