Example: What flow rate will you obtain for a steam valve
operating at relative upstream pressure 7 bar, Kv=0,7, and allowed
pressure drop ~650mm H2O?
Solution: The Dp pressure drop in
bar is 0,065. If you draw a straight line from the value 0,065 to the
curve P1=7+1=8 bar and, from this point of intersection, a
vertical line to meet the curve Kv=0,7, you can read on the right-hand
ordinate the flow rate of Q=12 kg/h.
Q =
flow rate in kg/h P1 = upstream absolute pression in bar Dp = pressure drop in bar K2= 1 for satured steam
2,5 for overheated steam
