Pressure reducing valve is direct acting regulator which regulate the downstream pressure to the adjusted point and the valve closes when the downstream pressure rises. Suitable for Water, steam and gas up to temperature 350°c with condensate pot.
Principle of operation:
Media flows through the upstream side of valve . The Plug with stem is connected to the actuator stem. The Downstream pressure is applied through control line to the actuator diaphragm where it is converted into spring force. With the set point adjuster, we can adjust spring pretension the required downstream pressure.
When the downstream pressure increases above the set point adjusted pressure, the valve closes proportionally to the change in pressure.
The balancing valve have balancing bellow where the upstream pressure act on outer surface of bellow and downstream pressure act on inside surface of bellow. As effective area of balancing bellow is equal to seat area the differential forces compensated so there is no effect of any changes fluctuations in upstream pressure.