These valves are installed on silos and hoppers in order to avoid overpressure during loading or depressure during unloading phase, which could compromise silo and/or filter body.

Intervention values can be calibrated by some specific sets of springs or counterweights.

Valves are available both with discharge into the atmosphere and with conveyed discharge according to what is foreseen by Lombardy Regional Law No. IX/3552 dated May 30, 2012.