I have a question regarding the selection of self-priming pumps
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I have a question regarding the selection of a self-priming pump: the required flow rate is 230 cubic meters per hour and the head required is 42 meters. Since I don’t have much experience with this type of pump, I chose a pump with two speed levels based on sample data； But they said that the two-tier version is too loud and lacks stability, so one should choose the four-tier version. So in practical application, is that really the case?
If the impeller is properly dynamically balanced, there will be no problem with excessive noise. A stage 4 motor pump is one size larger than both a stage 2 motor pump and its impeller.
This post was last edited by 3983596_FPPZ on 2019-6-12 at 14:36. With the same performance parameters, pumps with two-pole motors have a lower rotation speed than those with four-pole motors, and their cost is also lower. However, since they are self-priming pumps, the size of their internal chamber is determined based on the flow rate; there should not be much difference between two-pole and four-pole versions. The upgraded version of the foam also mentions that, since it is a self-priming pump, more attention should be paid to the pump’s net positive suction head. When selecting such a pump, in addition to ensuring that it meets the requirements regarding flow rate and head, it is preferable to choose a pump with a lower net positive suction head, thereby achieving greater self-priming capacity and a larger safety margin for suction, ensuring that the pump can still function effectively even in case of any abnormalities during actual use.
What does this have to do with a self-priming pump? Is it a problem with the motor, or is there an issue with the selection of the pump?
Do not use self-priming pumps; their efficiency is low. You can use the vacuum water lift tank with a pipeline pump mode.
For this model, with secondary cavitation, the noise level should be quite high
The inlet conditions aren’t fully specified. If the suction height is within 1 meter, a motor of grade 2 can suffice; but for heights over 1 meter, it’s better to opt for a motor of grade 4