When these valves reach a certain precalibrated vacuum degree, they introduce atmospheric air into the circuit to avoid the increase of the set
value and to keep it constant.

They can be used as regulators only on circuits having only one vacuum generator and only one use (or more uses but all working at the same
vacuum degree).

In most cases they are used as safety valves on tanks or containers not tested at the high depressions and on lifting systems with cups.

The vacuum degree adjustment is obtained turning the knurled bush in the two directions; thanks to its fine thread, a very accurate
calibration is assured.

Technical Data Sheet