Stage - Import export

Two-stage ventilation valve for release rates of 450 to 2000 m3/h in coarse and 20-40 m3/h in fine ventilation. For DN 80 and 100 housing material: EN-GJS-400-15, coating EKB; for DN 150 housing material S235 JR or P355 T1 and the coating consists of a wastewater-resistant Permacore thick micaceous iron ore coating First, air escapes during the first stage (coarse ventilation), until the medium closes off the first stage as it continues to flow. Any remaining air then escapes more slowly through the second stage (fine ventilation), until it is also closed. Gases collect, causing the fine ventilation to open once again until the medium closes this stage as well as it continues to flow.