Check valves can prevent medium backflow. When the inlet pressure is greater than the sum of the valve disc weight and its flow resistance, the valve is opened. On the contrary, when the medium flows back, the check valve closes. A check valve can prevent the pump and drive motor from reversing, and the valve disc acts on the valve seat by combining the fluid pressure and the self weight of the valve disc, thereby cutting off the flow. Check valves are used to increase the pressure in the auxiliary system to above the system pressure and prevent accidents.

Check valve, belonging to the category of automatic valves, has strong practicality and rich functions. So what is the function of check valve? Let's take a look right away.

1、 What is the function of a check valve

1. Check valve can prevent pump and drive motor from reversing

Due to the automatic operation of the check valve, the valve disc opens only under pressure flowing in one direction. When the liquid flows in the opposite direction, the pressure of the fluid and the self weight of the valve disc act on the valve seat, thereby cutting off the flow.

2. Check valves can prevent medium backflow

Check valves have only one flow direction, flowing along the direction of the inlet to prevent water from flowing back. The flowing medium flows in from the inlet end (lower side) and flows out from the outlet end (upper side). When the inlet pressure exceeds the sum of the weight of the valve disc and its flow resistance, the valve is opened. On the contrary, when the medium flows back, the check valve closes.

3. Increase pressure

Check valves are used to increase the pressure in the auxiliary system to above the system pressure and prevent accidents.

2、 What should be paid attention to when installing check valves

1. Check valves are mostly used for clean media and are not suitable for media with solid particles or high viscosity.

2. To avoid backflow of the medium in the pipeline, it is necessary to install check valves in both equipment and pipelines.

3. Compared with the swing type, the lift type has better sealing and greater resistance to fluids. Therefore, the straight type should be installed on a horizontal pipeline, while the vertical type should be installed on a vertical pipeline.

4. If it is a rotary type, there are no major limitations in its installation, whether it is a horizontal, vertical, or inclined pipeline, it can be installed. However, when installed on a vertical pipeline, the flow direction of the medium needs to be maintained in a bottom-up order.

5. If it is a straight through type, there are no major limitations in installation, and it can be installed on both horizontal and vertical pipelines.

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