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Anonymous Poster

centrifugal pump ?

11/03/2008 6:40 AM

Hi, friends, this is a specific case of centrifugal pump selection requirement, where static head may vary from 96 mlc. to 55 mlc. Normal operating duty point of a pump with 96 mlc. static head difference and available NPSH 21 mlc is 110 m3/hr @ 109 mlc. Can any one elaborate , what will happen if the same pump shall operate in the same system, which is rarely but may occur with static heed difference reduced to 55 mlc due to flood level in inlet pond ?
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PWSlack
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#1

Re: centrifugal pump ?

11/03/2008 7:39 AM

The flowrate will be greater than 110m3/h, and the pump manufacturer's model performance curve will indicate by how much.

A centrifugal pump operates where its performance curve and the piping system characteristic curve intersect.

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Hendrik
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#2
In reply to #1

Re: centrifugal pump ?

11/03/2008 10:53 AM

You can determine crossing point of the pipe system curve and the pump delivery curve. The friction component will rise due to higher flows.

Most pumps will need more HP. The efficiency is also mostly lower at this point.

If you now choose your driver big enough to cater for this high power requirement your system can run unattended at varying heads.

Alternatively you can install a flow regulating valve.

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PWSlack
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#4
In reply to #2

Re: centrifugal pump ?

01/08/2025 7:43 AM

Invitation declined.

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user-deleted-1104
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#3

Re: centrifugal pump ?

11/04/2008 1:57 AM

Please have a look to pump curve versus system curve.

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Previous in Forum: difference between Allan cap and Hex cap   Next in Forum: Log Splitter Beam
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