Flow Control - Air Release Valves

DAV-MH - Ductile Air Release Valve

Applications:
First Operation:
Venting air from a filling pipeline
The standard valve allows discharge of trapped air while the system is being filled with liquid. The valve will remain open, even at very high air flow velocity (A), until the liquid has reached the float and lifted it to its closed position (B). Available for valve models with suffix “K” and “KA”.
Second Operation:
Vacuum Breaking (Air Intake) of a draining pipeline
Decrease or the pressure in the system to negative value and the simultaneous drainage of the valve chamber, forces the floats down, allowing the admittance of air into the pipe, thus preventing negative pressure and possible collapse of the pipe (C). Available for valve models with suffix “K” and “KA”.
Third Operation:
Release of dissolved air from a pressurised pipeline
Air that is being released from the liquid in the pressurised system or being introduced into the system from open sources and pumping vortexes, accumulates in the air release valves located at high places. The accumulated air forces the liquid out of the valve chamber, so the floating force of the bottom float decreases. The bottom float then drops, allowing for the trapped air to be vented through the small nozzle at the center of the top float. Then the liquid level rises, the bottom float is lifted and the nozzle closes (D). Available for valve models with suffix “KA” only.

Product Code	Description
SIZE RANGE:	2” / 50mm to 10” / 250mm
PRESSURE RATING:	PN16 (230 psi), PN25 (350 psi) PN40 (580 psi)
MINIMAL PRESSURE FOR DRIP TIGHT SEALING:	o.2 bar
MAX TEMPERATURE:	65°C