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 A check valve, also known as a check valve, is an automatic valve that relies on the pressure of the flowing medium in the pipeline to push the valve disc to close and open the valve. When the medium stops flowing, the check valve disc closes and prevents the medium from flowing back in the pipeline, which plays a significant role in ensuring the safety of the pipeline.
How is the installation position of the check valve determined? What is the difference between pre pump installation and post pump installation of check valves, and where is pre pump installation applicable?
The installation of a check valve is to ensure the flow direction of water inside the water pump, thereby ensuring the normal operation of the water pump. Therefore, regarding the installation position of the check valve, whether it is installed in front of or behind the water pump, it can be divided into the following two situations:
1. One method is to install it at the end of the vertical suction pipe in front of the water pump, in order to fill the water pump without pumping water once, because when there is no water in the water pump and the suction pipe in front of the pump, the water pump can only run idle and cannot pump water. Therefore, the water pump must be filled with water in order to pump water. The installation of this type of water pump is a method above the liquid level, also known as negative pressure method, such as pumping water from a well.
2. Another method of installing a water pump is when the liquid level is higher than the water pump, usually used for secondary water supply. As the liquid level is higher than the water pump, it is convenient to start and stop the water pump without closing the water outlet valve, so the check valve should be installed behind the water pump.