Sanitary Check Valve is a common type of valve, which is widely used in various fluid systems. It is mainly composed of valve body, valve, spring and operating mechanism. The main function of the spring check valve is to prevent the backflow of fluid and ensure the normal operation of the system. In the pipeline system, the spring check valve can be installed at the outlet of the pump or the end of the pipeline to prevent the backflow of fluid when the pump is stopped or the system pressure is reduced. When the fluid flows forward, the spring is compressed and the valve disc opens under the action of the fluid pressure: when the fluid flows in the reverse direction, the spring stretches and the valve closes under the action of the spring force to prevent the backflow of the fluid.

The working principle of the spring check valve is based on the balance between the pressure of the fluid and the elastic force of the spring. When the pressure of the fluid exceeds the opening pressure of the valve, the valve automatically opens and the fluid can pass smoothly. When the pressure of the fluid is lower than the closing pressure of the valve, the valve automatically closes to prevent the backflow of the fluid. Specifically, the valve of the spring check valve is usually a movable disc or sphere, which can move freely in the valve body. When the pressure of the fluid exceeds the opening pressure of the valve, the valve disc is pushed open and the fluid can pass. At this time, the spring is compressed and some energy is stored. When the pressure of the fluid is lower than the closing pressure of the valve, the spring pushes the valve back to its original position to prevent the fluid from flowing back.