Novel reverse flow preventing device

Abstract

The invention discloses a novel backflow preventer. The preventer comprises at least two check valves which are communicated with each other and in series connection. A water escape valve is connectedto and communicated with a valve body of the water exit section of the first check valve; the first check valve comprises the valve body; a valve seat is arranged on the inner wall of the valve body;a valve clack is arranged in the valve body and sealed with the valve seat; an elastic device is arranged on the valve clack; a movement constraint guide rail of the elastic device is arranged on theinner wall of the valve body; and the other end of the elastic device comes into contact with the movement constraint guide rail. The backflow preventer with the above structure can accurately sensethe operating state of a system pipeline, and provide feedback when a backflow trend happens to a medium or a pipe explosion accident occurs before a valve, so as to preventing the medium from the backflow. By adopting the structure, the reached performance index exceeds the provision of the national standard CJ / T160-2002. The preventer can effectively prevent drinking water and other clean waterfrom being polluted, and is suitable for occasions with strict requirements for water quality of drinking water systems and pipe systems.

Description

technical field [0001] The invention belongs to a hydraulic control combination device for one-way flow, and in particular relates to a novel backflow preventer. Background technique [0002] In order to prevent the backflow of sewage from the pipe guide in the water pipe network, two check valves connected in series are generally required to form a backflow preventer. The backflow preventer is mainly used in direct drinking water systems and occasions that have strict requirements on the water quality of the pipeline system. The head loss of the current backflow preventer is generally 0.7kg / cm 2 , the water head loss is relatively large, and the water supply pressure must be increased during normal water supply, which consumes a lot of energy. And this structure is more complicated. At the same time, the check of the current pipeline check valve is realized by the force of the spring. When the valve is closed, the spring force is the smallest, and when the valve is full...

AI Technical Summary

Problems solved by technology

When the valve is closed, the spring force is the smallest, and when the valve is fully open, the spring force is the largest, so when the flow rate of the system decreases, the valve is often in a half-open state under the action of the spring force; when the valve is checked, the valve is closed The spring force is the smallest when the valve is closed, so no effective check can be formed when the valve is closed; the spring pressure is the largest when the valve is fully open, which seriously affects the system efficiency

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