These valves are primarily used where containers and pipes have to be aerated and/or vented. The float in the type 591 opens the valve 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"
- Valve can be positioned at absolute & temporary high points, after pumps or at turning points