Help, I need help from fellow travelers
Thread Content
When a 750W plastic magnetic pump was tested with water, it was able to pump water when the outlet valve was fully open, resulting in maximum flow and minimum pressure. However, when the outlet valve was gradually closed to increase the pressure, the pump stopped pumping water and the noise it produced decreased. The pump was then shut down and the outlet valve closed; upon restarting it and slowly opening the outlet valve again, the pump still could not pump water – only with the outlet valve fully open could it start working. It was checked that the magnetic core had not lost its magnetism, that the impeller rings and thrust plates were in good condition, and that there was no air in the piping. I would be very grateful if experienced users could offer some advice!
Who starts a centrifugal pump with its outlet fully open? In the case of magnetic pumps, decoupling can easily occur.
Normally, it should be started by closing the outlet valve, but it fails to start under normal conditions