Regarding the flow rate issue of the hot oil pump
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Dear experts, for this bottom-hot-oil pump of mine, the temperature of the gasoline medium is around 210 degrees. When it was put into operation in March, its flow rate was approximately 245 t/h. It was then switched to a backup pump for half a year, before being switched back to this pump in November. The flow rate at the pump’s outlet was 235 t/h, which is about 10 t/h less; the outlet pressure was also 1 kilogram lower. However, the pump operated stably, without any abnormal vibrations or noises. No maintenance work was carried out on this pump during that period, and the inlet filter screen was clean. I would like to ask the experts: what could be the reasons for the decrease in flow rate and pressure of this pump? Is it related to the temperature? The pump body is not insulated; the temperature is around 20 degrees in March and around 0 degrees in November. Thank you for your advice
Has the current changed? If the current doesn’t change much, it might be that the gap in the mouth ring has increased.
Has there been any change in operating conditions? Is the liquid level in the tower lower than before? A lower liquid level means a decrease in inlet pressure
The return valve or the outlet valve of the standby pump is not fully closed. Or internal leakage in the check valve of the standby pump
The current has actually increased compared to before, going from over 180 to over 190
The operating conditions remain unchanged, and the quantity of the standby pump is roughly the same as that of this pump before; after switching to this pump, the quantity decreased
The outlet valve of the standby pump should be tight; when I switch pumps, the standby pump does not stop operating – only its outlet valve is closed. Since the pressure in the standby pump is higher than that in this pump, there should be no flow from this pump to the standby pump
Is there a return pipeline? If the current is high, it’s possible that 1) there is significant internal circulation within the pump, or 2) there is a bypass for return flow. Take a look
First, check the properties of the material in the tower bottom, such as density and viscosity, as well as whether there are any changes in the liquid level in the tower bottom. If these factor changes are excluded, then check whether the check valve is not fully closed or has internal leakage ； Only at the end was the issue with the pump equipment itself checked.
This phenomenon is indeed strange; an increase in current indicates an increase in the pump’s output, meaning that the pump’s flow rate increases while its head pressure decreases. If the information provided by the poster is accurate, there is only one possibility: the performance of the pump has declined. You can use WeChat or phone number: 13162294857