I use water pump pumping 78 meters deep underground water, the pipe is 2.5 inches large, with ordinary check valve, water is always sucked back, I would like to ask what method or what kind of check valve to be selected (check valve to be installed on the side of the pump)
The ideal way is to set up a vacuum tank so that it doesn't return all the time without irrigation each time. Check valve because of different quality, more or less water leakage, stop time will be long after the leak.
(1) for high and low pressure check valves under DN50mm, vertical lift check valves and straight through lift check valves shall be used.(2) for low pressure check valves under DN50mm, butterfly check valves, vertical lift check valves and diaphragm check valves shall be used.(3) for DN larger than 50mm, less than 600mm high and medium pressure check valve, it is better to use the swing check valve.(4) for DN is larger than 200mm, less than 1200mm of medium and low pressure check valve, should choose no wear ball check valve(5) for DN larger than 50mm, less than 2000mm low pressure check valve, butterfly butterfly valve and diaphragm check valve should be selected.(6) for the requirements of closing perfume, impact is relatively small or no water impact on the pipeline, you should choose the slow closed swing check valve, butterfly butterfly valve.(7) for the import pipeline pump, should use the bottom valve.
1, do not use ordinary ball check valve, rubber check valve, quick response, but it is not very durable2, vacuum tank3, I think the most benevolent is, get an auxiliary start pump, small kind of, the head is not too high, connect the municipal pipe network, open the main pump before the auxiliary pump irrigation. But the premise is that your main pump is a centrifugal pump
