Self-acting pressure reducers are simple control valves offering accurate control while being easy to install and maintain. They control the pressure downstream of the valve without requiring pneumatic or electrical control elements.
The DM 620 - 628 pressure reducing valves are diaphragm-controlled spring-loaded and balanced proportional control valves for high inlet and outlet pressures. They can be supplied with three types of connections: sockets, flanges or welding spigots. Each size of valve may be fitted with three different seats. The valve cone may be fitted with a soft or metallic seal.
The outlet pressure to be controlled is balanced across the control unit by the force of the valve spring (set pressure). As the outlet pressure rises above the pressure set using the adjusting screw, the valve cone moves towards the seat and the volume of medium is reduced. As the outlet pressure drops, the valve control orifice increases; when the pipeline is depressurised, the valve is open. Rotating the adjusting screw clockwise increases the outlet pressure.