Schroeder Valves

SDV Series

Back pressure device SDV

Our back pressure device does not allow the static pressure in the upstream pipe to fall below a defined minimum value. It does this independently of the flow volume. This means that the specified minimum pressure is maintained, from the nominal flow rate to the smallest volume. Normally back pressure devices are used to avoid cavitation and partial evaporation in the pumping medium. By increasing the pressure level in the system component to be protected, they stop local steam pressure from falling below requirements. The SDV has an integrated return function, i.e. the system is also protected against reverse flow if needed.

Active Principle

The active principle of the SDV is based on a spring-loaded locking cone. The cone and spring are coordinated in such a way that once the specified holding pressure has been reached, the pressure force is sufficient to lift the cone out of its seat, thus permitting flow. Unlike conventional back pressure devices / counter-pressure regulators, the cone of our back pressure device has been equipped with a control profile. This allows the throttle surface at the cone seat to accurately adapt to the relevant flow rate, thereby minimizing the unfortunate tendency of spring-loaded locking devices to produce knocking or hammering noises at low flow rates. The SDV is therefore suitable for systems with a wide operating range and frequent partial load operation.

Further information about the product series may be obtained in the datasheet.


Datasheet SDV Series 2