Ductile Iron Double Orifice Air Release Valve QB2-16Q

Product Description

The QB2 Double Orifice Air Release Valve consists primarily of a valve body, valve, top cover, valve stem, float, and air vent nozzle. It is designed for use on water and hot water pipes with an operating temperature not exceeding 80℃ to completely remove air from the pipes. When it is necessary to vent air from the pipeline, rotate the valve stem counterclockwise to raise the valve stem and valve assembly. This allows air within the pipeline to enter the valve body cavity under water pressure and be expelled through the vent nozzle. Subsequently, water from the pipeline fills the valve body cavity, causing the float to rise due to buoyancy and seal the vent nozzle, thereby achieving automatic sealing. During normal pipeline operation, air in the water is continuously forced into the upper part of the air release valve body by water pressure, causing the float to descend and move away from its original sealing position. At this point, air is again expelled through the vent nozzle, after which the float returns to its original position to reseal the valve. Therefore, during normal operation, the valve remains open at all times, and the float continuously repeats the above cycle to expel air. The valve should be closed when maintenance or cleaning of the valve body is required. To close the air release valve, rotate the valve stem clockwise.

How It Works

When water begins to flow into the pipe, the plug remains in the open position, allowing a large amount of air to be vented. Once all the air has been vented, water accumulates inside the valve, causing the float to rise and driving the plug to the closed position, thereby stopping the venting of air. When water is being normally conveyed through the pipe, if a small amount of air accumulates inside the valve to a certain extent, the water level inside the valve drops, and the float drops accordingly, at which point air is vented through a small orifice. When the pump stops, the pipe empties of water, or negative pressure develops within the pipe, the plug opens rapidly to draw in air, ensuring the pipeline remains fully pressurized.

Product Features

1. It can remove gas from the pipes, reducing resistance and saving energy.
2. When negative pressure occurs in the pipeline, this product can quickly and automatically draw in air to prevent the pipeline from rupturing.
3. Its venting capacity is several times that of a standard two-hole air release valve.
4. The float bracket is made of stainless steel, ensuring a long service life and making it safe and reliable.

Product Specifications

Airflow Rate per Hour

Product Size Guide