Double Orifice Air Release Valve
Materials：
SPECIFICATION
Hivent double orifice air Release&Vacuum valve that combines both large orifice&small orifice functions within one unit,the large orifice allows air to be expelled from the system during filling of a pipeline and admit air back into the system wheneversub-atmospheric pressure occurs.Air is vented from the system until water enters the valve and lifts the float against its
seat,ensuring a tight seal.In the event of sub-atmospheric pressure in the system,the water level drops causing the float to fall from its seat and allow the admission of air.
During normal working of the main the small orifice releases the air which accumulates under pressure.With the main in operation,the fioat is normally against its seat.As air enters the chamber body the water level is depressed until a level is reached when the float drops form its seat,whcih allows air to escape.The consequent rise in water level returns the float to its seat.
ABS float & float guide, A4 bolts, 300 µ coating, DN50-200
Air relief valve for drinking water (not wastewater) and neutral liquids max. 70° C
Double orifice, triple acting air valves are designed for automatic rapid pipe filling and pipe draining as well as for automatic discharge of accumulated air during normal working conditions. The unique ‘Aerokinetic’ design, where air rushing out of the system cannot force the float upwards and close it prematurely, makes sure that the valve closes only after all air has left the system and water has entered the chamber. All ductile iron components are coated with GSK approved fusion bonded epoxy to ensure high durability. All other components are made by either a WRAS approved polymer material or stainless steel to minimize corrosion risk. All seals are made of WRAS approved EPDM rubber featuring an excellent compression set and ability to regain its original shape.
Features
A clever float design prevents air rushing out of the system from prematurely closing the valve
Large air flow capacity
All iron parts with contact to the water are coated with drinking water approved, fusion bonded epoxy
The resilient seals are made of EPDM rubber and the seat is ABS, all drinking water approved
All other internal parts are highly corrosion resistant AISI 316 stainless steel or ABS
No moving parts are touching the internal coating
The complete product is approved for drinking water
