Analyze why the magnetic pump is not delivering any flow
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Some time ago, the magnetic pump wasn’t able to deliver the required flow rate; for more details, see http://bbs.hcbbs.com/thread-376614-1-1.html. The issue of insufficient flow was resolved today by thickening the gasket on the cover by 0. It’s around 5 mm. Could you help analyze why adding a thicker gasket made it possible to operate the device? It turns out that there was no pressure at all; if the impeller got stuck due to a small gap, then the magnet should have lost its magnetism, but that didn’t happen. Moreover, when the power is turned off in order to address the problem, the pressure gauge exhibits fluctuations. I hope everyone can help analyze it.
Bearing wear or a small impeller clearance results in slight slip during short periods of idling, which has little impact on the magnets
I wonder if there is a significant difference between the center of the flow channel in the impeller and that in the pump casing. Could the original poster tell me what the pressure difference between the front and back is?
When the pump runs idle or without any load, it is recommended to install an anti-idle protection device for the pump; this device will shut down the pump automatically within 2 seconds of idling, thereby protecting the pump from damage. The address for the electronic sample is: http://www.dnpump.com/PicUp/200910162202501.pdf If you want to minimize maintenance efforts, it’s better to use such an anti-idle protection device – it makes things much simpler!
Does adding a pad cause fluctuations in the pressure gauge?
My understanding of these might be quite basic, but I still want to learn a bit! I think the reason for the increase in volume after adding padding can be attributed to the position of the outlet flow channel and the impeller flow channel; additionally, it’s possible that the 0.5-times enlarged gap has caused air to enter, leading to cavitation or the presence of air within the medium! Could it be that when you stop the pump instantly, this 0.5-inch cushion creates a pressure difference between the outlet and the inlet, resulting in fluctuations in the pressure gauge? Is there an impact from back pressure and shaft string length? The design of the flow channel structure in the impeller also has an impact on pressure changes! It must be a problem with the process!
A regular centrifugal pump shouldn’t be as complicated as you think; issues like cavitation would at least cause pressure fluctuations along with noises, but the original poster didn’t seem to mention these problems. My guess is: since the pressure dropped to zero with no change, it can be fairly concluded that the shaft is no longer rotating. If the shaft isn’t rotating, then something must be jamming it. Increasing the thickness of the pump cover resolved the issue, indicating that the jammed part was the impeller. As for why there was no overcurrent when the shaft got stuck? This indicates that the magnetic drum of the magnetic pump itself has lost some of its magnetism. This can be confirmed by what was mentioned in the original post at http://bbs.hcbbs.com/thread-376614-1-1.html, where it is said that \"the flow rate was sufficient at the beginning of operation, but it decreased once the flow rate was increased to the required level.\" Moreover, when the inner and outer magnetic drums do not rotate in sync due to the loss of magnetism, this results in fluctuations in current and pressure readings when the pump is turned off"