Magnetic pump failure
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The system magnetic pump can operate normally at room temperature, but when the liquid temperature rises to 40 degrees, it fails to deliver flow. We determined that this is caused by cavitation; then why does no malfunction occur at room temperature? The manufacturer says it’s due to the poor self-lubrication effect of the pump. Please have the experts discuss why this is the case
We also need to take into account the properties of the medium; if it is a volatile medium, temperatures reaching 40°C may cause cavitation
Will the transport medium vaporize at 40 degrees? Another possible reason is that the viscosity of the medium being transported varies greatly; at 40 degrees, its viscosity is very low, which leads to internal leakage within the pump, and as a result, the pump’s flow rate is insufficient
What medium is it? If the self-lubrication is not good as claimed by the manufacturer, it is also caused by changes in the properties of the medium. As the temperature rises, the viscosity of the medium decreases, causing poor operation of the sliding bearings; the impeller stops rotating, resulting in insufficient flow rate.
The medium is an organic diamine that does not volatilize at 40, and its viscosity does not change significantly. We have two high-temperature pumps that transport the same medium, and there are no problems with them.
If no vaporization occurs, cavitation can basically be ignored here. If a magnetic pump experiences insufficient flow rate as the temperature rises, it is very likely that the magnets lose their magnetism due to the increased temperature, which in turn results in insufficient magnetic drive. But it’s only 40 degrees, so demagnetization should not occur. Domestic manufacturers can also achieve around 100 degrees. Consider magnetic loss.
I’m not sure what the medium is; if this temperature exceeds the saturated vapor pressure, cavitation may occur
If the medium does not vaporize, should we consider whether there is any blockage in the inlet pipeline?