These valves are primarily used where containers and pipes have to be aerated or vented. The float in the type 591 valve opens if the level of the liquid falls. If the level of the liquid rises, the float is raised and pressed against a seal. The valve is then closed. Ventilating and bleed valves are mainly used for de-aerating of air, while filling piping systems and tanks, avoiding vacuum and discharging air pockets.
- FPM or EPDM seals
- Valves supplied with threaded & socket end connectors
- Installed vertically with the arrow pointing up
- The valve can be positioned at absolute & temporary high points, after pumps, or at turning points