What is the difference between a regular centrifugal pump and a self-priming pump? For use in the chemical dosing room!
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Used in the chemical dosing room to pump chemicals from the dissolution tank into the solution tank – should an ordinary centrifugal pump or a self-priming pump be used? The attachment is available in two formats! Thank you. 1. I checked the information available online; self-priming pumps have a relatively high suction lift, meaning that the height at which water can be drawn up is high, and thus the installation height can also be high. However, their efficiency is low – I’m not sure why the efficiency is low in this case ； 2. If it is a self-priming type, that is, the liquid level is higher than the axis height of the suction pipe, then is it unnecessary to use a self-priming pump? A regular centrifugal pump will suffice; in other words, where a centrifugal pump can be used, a self-priming pump can certainly also be used, but this is not always the case the other way around. Thank you
A self-priming pump is essentially the same as a centrifugal pump; they are pretty much identical. What you’ve drawn here shows two different installation methods, or installation heights, and these have nothing to do with self-priming capability
A self-priming pump is essentially a conventional centrifugal pump with a special pump casing that allows it to store a certain amount of liquid; this enables it to draw water from a location lower than the pump level without the need for priming, even when there is air in the inlet pipeline
Hello, the difference between these two installation methods lies in the self-priming height; the suction lift of a self-priming pump should be higher than that of a centrifugal pump, right? The second method requires a relatively high self-priming height, I guess
For your diagram, for the first case a regular centrifugal pump will suffice; for the second case, a self-priming pump is needed. A self-priming pump is one that can prime itself. In the first diagram, the medium flows in reverse direction, while in the second diagram the pump needs to draw the medium up from a pit, which is why a self-priming pump is required.
In simple terms, a self-priming pump is a centrifugal pump to which a self-priming mechanism has been added, eliminating the need for manual priming! If the suction height is higher than the pump inlet, there is no need to use a self-priming pump
The instructions in the chemical dosing room say that the amount used shouldn’t be very large; wouldn’t it be better to use a metering pump?
Chemical dosing room: metering pumps as per standard design
For self-priming systems, there is no need for a self-priming pump; ordinary centrifugal pumps installed above the liquid level require priming to remove air from the pump. Suction pumps also have requirements regarding the installation height; however, since the medium is already contained within the pump, there is no need to fill it. Yet, if the height is too great, pumping will still not be possible.