WAM Spring-Loaded Pressure Relief Valves consist of a cylindrical casing with a bottom flange to be connected with a spigot welded on the silo roof, a disc shape inner steel lid for negative pressure operation held in position by a central spring rod, an outside steel ring for excess pressure kept in position by three spring rods, gaskets, and a weather protection cover.
Helical springs keep the valve lids closed when the pressure value remains within the preset limits. The three outside spring rods keep the external ring-shaped lid firmly closed as long as the force generated by the pressure inside the silo does not overcome the spring force. Once the pressure exceeds the preset value, the lid is pushed up and pressure can escape. The smaller lid covers the central circular opening of the external lid from below. It’s held in the middle by a single spring rod and is pressed onto the external lid by the normal air pressure inside the silo. In the event of suction pressure, the spring is compressed and allows the lid to drop. The air entering the silo from outside ensures rapid pressure balance and pushes the central lid back up into “closed” position.
- Flow rate: up to 13,000 m3/h (7,650 cfm)
- Painted carbon steel or 304 stainless steel casing
- Stainless steel weather protection cover
- Mechanical set-up for inductive signalling sensor
- Preset for maximum negative pressure of -0.005 bar (-0.07 psi) and maximum excess pressure of 0.05 bar (0.72 psi)
- Lightweight design and reduced overall dimensions for extremely comfortable handling
- Easy to fit
- Quick maintenance
- ATEX-certified version
- Compliance with European Regulation (EC) No. 1935/2004
- Optionally different settings available
- Inspection hatch
- Inductive sensors
- Bird net