Diaphragmatic double chamber pressure relief valve. It is actuated when there is overpressure in the the netowork.
Types available: AS-A/Y-30 ‘Y’ configuration , ΑS-A/T-30 angle shaped, AS-R/Y-30 threaded connections
for pressures exceeding 25atm piston type valve AS-P/Y-30 is recommended.
The pressure relief and sustaining valve ΑS-A/Y-30, protects the pumps and pipes from damages caused by surge waves due to the rapid changes of the water flow. The common causes of rapid changes in flow are the starting and shut-down of pumps, fast closure/opening of valves, filling of drained pipe at excessive flow rates, etc.
The valve ΑS-A/Y-30 sustains the desirable upstream pressure, regardless the changes of the flow. In case the upstream pressure is reduced bellow the regulated limit, the pilot closes the valve.