Direct-activated pressure reducing valve directly opens and closes the valve gate by the outlet pressure. When outlet pressure is under setting pressure, valve gate automatically opens. To make valve gate fully open, adjustable pressure range and setting pressure are relative points.
A: Pressure drop needed for fully-opened valve gate = , B=Adjustable Pressure Range Maximum – Minimum
B¡GAdjustable Pressure Range (=Maximum Minimum Adjustable Pressure Range)
C¡GSetting Pressure of Outlet
D¡GPressure of fully-opened outlet valve gate, P=C-A
Pressure drop needed for fully-opened valve gate for adjusting pressure range 3~9 kgf/cm2 of direct-activated pressure reducing valve.
If the setting pressure of outlet is 6kgf / cm2, pressure of fully-opened valve gate will be
P=6-1.5=4.5 kgf/ cm2(Outlet pressure should go down under 4.5kgf/ cm2 to make valve gate fully open)