NETWORK PROTECTION VANADOUR® AIR VALVE Types Air valve : - Small orifice air valve - Single large orifice air valve - Double orifice air valve - Flow capacity chart Air relief valve Construction Air valve : Body and cover cast iron Spherical and/or cylindrical float Flange connection ISO PN 10-16-25 ANSI or screwed Air relief valve : Carbon steel - Stainless steel Materials - Special Features/Benefits - Principle Air valve : Allows the air to got throught during the filling or the emptying of the pipe. When water lift, the float(s) seal(s) one or two orifices(s). The air valve facilitate  the flow of  the water and avoid surge. The air valves are located at all peak points of the line Air relief valve : A preloaded spring allows the aperture of the nozzle when the setting pressure is exceded Applications Air valve : Water mains, water network, irrigation, fire lines Air relief valve : Sewage Approvals -