DF41X backflow preventer

Detailed information of the backflow preventer

The working principle of the backflow preventer is to use the medium to reduce the pressure due to mechanical resistance and overflow head loss when the medium flows through the inlet check valve, so that the inlet pressure is higher than the discharge The pressure in the water valve chamber, and the pressure on the upper part of the drain valve diaphragm is the inlet pressure. The pressure on the upper part of the diaphragm is greater than the drain valve chamber and spring resistance. The drain valve remains closed and the medium flows normally. When the inlet pressure and the drain valve chamber When the pressure difference is less than cavity, forming an air partition to prevent the backflow of media. When it is larger than .
The backflow preventer is a hydraulic control combination device that strictly limits the flow of water in the pipeline to only one direction. Its function is to prevent the backflow of the medium in the pipeline under any working conditions, so as to avoid backflow pollution. The water pressure in the pipe network behind the valve is higher than the water pressure at the water end in front of the valve. If the seal of the second one-way check valve is intact, the water will not flow back. At this time, the drain valve is closed and no water will be released. When the second one-way check valve is sealed, When failure occurs and leakage occurs, the drain valve opens to drain water and relieve pressure.