-No external power, energy receives the water flowing through the pipe.
-Simplicity In the design, construction and operation.
-Stable and accurate control of the flow.
The pressure sustaining valve is activated by the line pressure and regulated by the pilot valve. It includes a diaphragm that controls the opening or closing of the main valve upstream pressure by sending more or less pressure to the control chamber of the main valve.
If the upstream pressure drops below the set at the pilot valve it tends to reduce the flow of water or increasing pressure to close the set in the pilot. When the upstream pressure rises above the set at the pilot valve opens by decreasing the pressure set on the pilot.
The hydraulic pressure sustaining valve is used when a minimum downstream pressure is needed or when you want to reduce pressure shocks upstream.