Vacuum and pressure relief valves

With the help of vacuum and pressure relief valves, it is possible to avoid the emergence of underpressure (vacuum) in the piping or tank or the formation of excessive overpressure in the system.

Vacuum gives rise to a state of disturbance

Although ‘vacuum’ usually refers to quite low pressures, even large tanks are known to collapse under its influence and other operation disturbances can occur in the systems.

The valves by GESTRA, NIEZGODKA, and AWH are designed for relatively small size classes and flow rates. The section Vent valves for tanks includes corresponding pressure and vacuum relief valves for gas, but their set pressures are clearly lower than those of the valves described on this page.

On request, we also offer tailored vacuum relief valves for higher capacities.

Typically spring-operated

Pressure and vacuum relief valves are spring-loaded and open if the set pressure is exceeded. Depending somewhat on the model and desired flow rates, wedge solutions of different sizes can be added to the valves in order to increase their capacity. A slight exception is the GESTRA RK 86A valve, which is a non-return valve, but is also used as a vacuum relief valve owing to its excellent tightness.