The flow rate of the centrifugal pump is very low when it is raised 2 meters
Thread Content
There is a pump with a flow rate of 1 cubic meter and a head of 10 meters, used for pumping water. In actual use, a head of around 4 meters is sufficient; it has worked normally with a high flow rate. This time it rose by 2 meters, a new pipe was installed, and the water flow became very, very low. After dropping 2 meters, the normal water output increased again. What is the reason? The pipe is new, so air leakage can be ruled out. The pump’s head is 10 meters, so why does the flow rate drop significantly after rising just 2 meters? If there’s a blockage or the impeller is damaged or something, then why does the water flow increase when the level drops by 2 meters?
The pump is too small, resulting in high resistance in the outlet pipeline
Thank you for the guidance. I have a question: so how should this be resolved now?
If the pump is fine, the problem must lie in the outlet pipeline, such as pipeline resistance or too many bends.
This post was last edited by wxbfljj on 2017-6-12 09:21 :)
Thank you for the guidance; the pump should be fine – it’s quite normal for water to flow out when the level drops by 2 meters. It doesn’t work if it goes up 2 meters; there are 2 bends.
Is 1 square decimeter the standard parameter for this pump? So what’s your current data usage at 4 meters? Also, is the newly installed 2-meter pipe the same size as the 4-meter one?
1 cubic meter per 10 meters is the standard parameter. A flow rate of 4 meters is normal. The newly installed pipe is the same size as the previous one
This post was last edited by xxmm1234 on 2017-6-12 at 13:36. The pump is suffering from cavitation; the height of the static liquid column must be greater than the pump’s net positive suction head, otherwise cavitation will occur and the impeller can be damaged. The pump vibrates during cavitation; keep an eye on it.
The installation height exceeds the required net positive suction head of the pump.