Hi all,(adsbygoogle = window.adsbygoogle || []).push({});

I have a question about the effect of partially closing a pump discharge valve on the system curve, wondering if you guys can help me out.

Right now I have the yellow pump curve and the orange 2 inch system curve , producing around 120 gpm against around 110 ft of head. If I expand the piping from 2 inch to 3 inch I end up with the grey system curve. The grey system curve doesn't intersect with the pump curve so this way of operating is not possible in my understanding; However, using the grey system curve, if I partially close the pump discharge valve to artificially increase the head so that the total head becomes 110 ft, would the new operating point be the same as before (120 gpm against 110 ft of head)? Similarly, if I partially close the discharge valve so that the total head becomes say 100 ft, would the operating point be around 130 gpm against 100 ft of head?

Any help is appreciated, thank you guys.

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# Partially closed pump discharge valve question

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