YQFGP Compound Quick Air Inbreathe-release Valve (Hereinafter referred to as air release valve) is a special air inflow and exhaust control device applied in water supply and drainage pipeline. When filling an empty pipe with water, air will then be quickly exhausted out of the pipe automatically. During operation in a pressurized pipeline, the small air vent orifice is sensitive, and air in pressurized air bag can be duly exhausted out of the pipeline so as to keep the flow smooth and improve efficiency of water supply; When the inside of pipeline has negative pressure differential, air will then quickly inflow to disturb vacuum so as to prevent pipeline from unstable failure due to large negative pressure differential, or reduce waste water suction from the pipeline leakage point causing the pipeline contamination. When emptying water from the pipeline, air will fill in great amount automatically and water will be speeding up discharging, and therefore shortening the time of water cut-off. When in proper operation, it can eliminate the water break damage to pipeline due to water hammer caused by pump shut-off, so as to keep the pipeline net in stable and safe operation. Owing to its quick action of air exhaust, sensitive small air vent orifice, and stable performance capacity, as well as high safety coefficient, etc., it is essential for long distance water supply pipeline with large DN.
