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Definition: The backflow preventer is a type of hydraulic control device which can strictly control the water inside pipeline to flow in one direction, and consisted of two separately functional check valves and a drain valve.

   Application:    The backflow preventer is applied to high, general, and low risk of contaminated area.

Technical Features
A.Adopting two separate check valves structure, the two end springs of both check valves having relatively strong preload force ensure a quick action. Prior to occurring backpressure or backsiphonage reverse, check valves could complete actively, beforehand, and timely closed action.

B.The two separate spring assisting closed action of check valves system and the pressure differential drain valve system in middle chamber have no mechanically connection beside they are operated in one valve body. Such designing structure means these parts are operated independently, and therefore they will not turn up coexisted mechanical glitches and ensure a highest safe handling. .

C.Reduced-pressure type backflow preventer has been publicly regarded as backflow preventer control device with the highest safe protection class. It has gradually applied widely in domestic water supply engineering projects.