Does the self-priming pump need to install a bottom valve?

The common self-priming pump refers to the external mixing suction and filtration self-priming pump. According to the rotation of the centrifugal impeller, the liquid flows into the volute, and then the pump shell generates a vacuum pump. In that way, the product of the self-priming pump will start, suck the liquid in from the inlet, and transport the liquid out according to the path of the impeller. It is the principle of the self-priming pump.
An obvious feature of self-priming pump different from centrifugal pump is that it does not need to inject water in the case of application. However, in the case of a single application, you must remember to inject water into the pump cavity. Because the pump shell itself does not store liquid, if you do not inject water in the case of a single application, the pump will rotate at a high speed, which will not only prevent the liquid from being sucked up, but also continue to burn the mechanical seal and other parts of the pump shell due to the high rotation speed. Therefore, you must pay attention to this.
So should the self-priming pump be installed with a bottom valve
01
If the bottom valve is not installed
What is the situation?
Generally speaking, there is no need to install the bottom valve. Generally, the inlet of the self-priming pump is equipped with a check valve, which is often referred to as this product, so after the pump is terminated, the liquid in the pump body cannot flow back to the original pool and be stored in the pump body, so there is no need to add liquid in the case of the second application,
02
If the bottom valve is installed
What about the situation?
If the bottom valve is refitted, the actual effect will be better, because sometimes if this product is destroyed, there is also a bottom valve as a guarantee, which is not easy to appear high speed, and after refitting the bottom valve, it will also reasonably ensure the reasonable suction lift of the pump!
Another special case, but if there is too much difference in the suction height width ratio, or the suction pipe is large, and the volume exceeds the liquid storage in the self-priming pump cavity, everything cannot work normally. At this time, it is necessary to refit the bottom valve to ensure the rapid safety of natural suction.

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