Type 502

Pressure Reducing Valve

For liquids, gases and steam up to 266° F.

Pressure reducing valves control the pressure at the outlet side.

The type 502 pressure reducing valve is a diaphragm-controlled, spring-loaded proportional control valve made of CrNiMo-steel with smooth surfaces. The valve cone has a soft seal. Setting screw and spring are integrated so that altering the pressure setting does not charge the length of the unit. The sealing quality is equal to or better than VDI/VDE guideline 2174.

With depressurized pipeline the spring keeps the valve cone in open position. Under pressure the medium flows from the inlet side through the valve seat into the body and acts on the diaphragm/spring system from the outlet side (outlet pressure).

The outlet pressure balances the force of the valve spring across the diaphragm (set value). As the outlet pressure rises above the pressure set using the setting screw, the valve cone moves toward the seat causing the flow to be restricted. As the outlet pressure drops the restricting orifice becomes larger. The valve is fully open if the pipeline is depressurized. Rotating the setting screw clockwise increases the outlet pressure.

The maximum permitted outlet pressure is 1.5 times the set pressure, unless otherwise specified.

With outlet pressure K 1.1 bar a sense line has to be installed.

If toxic or hazardous media are used the valve must feature a sealed spring cover (including setting spindle seal) fitted with a leakage line connection. When the overflow valve is installed on site a leakage line must be fitted capable of safely draining the escaping medium in case the control valve should become defective.