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Anonymous Poster

Pump with Low Efficiency

11/10/2010 12:43 PM

For horizontal centrifugal booster pumps , to pump potable water , the rated point is 150 m3/hr and 320m head , 300hp motor . after conducting the factory performance test , the test results show the pump with lower efficiency comparing to the contract original documents , the efficiency value difference is still within the limits of the standard of testing (ISO 9906) , BUT the value still low , about 71 % efficiency .. my concern is to know the main causing for having this low efficiency value .. what are the main causes for the low efficiency of pump in general . is it related to the bad machining , bad assembly .. the opertaing point !!!! any inputs will be highly appreciated ???
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Unredundant
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Join Date: Feb 2008
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#1

Re: Pump with low efficiency

11/10/2010 12:49 PM

Mass production and the fact that the ISO standard has an elliptical "window".

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MrGeneRall
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#2

Re: Pump with Low Efficiency

11/10/2010 1:46 PM

Are you taking about motor efficiency or mechanical efficiency here?

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Anonymous Poster
#3
In reply to #2

Re: Pump with Low Efficiency

11/11/2010 2:46 AM

I am talking about the mechanical efficiency (the pump efficiency), and this valve will affect the total hydraulic efficiency.
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Codemaster
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#4

Re: Pump with Low Efficiency

11/11/2010 7:24 AM

You don't say what the efficiency is meant to be, but 71% doesn't sound too bad. Motor looks somewhat oversized, unless it's to cover a run-out condition.

Codey

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pritam
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Engineering Fields - Mechanical Engineering - New Member India - Member - New Member

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#5

Re: Pump with Low Efficiency

11/17/2010 1:58 AM

Efficiency may depend mainly on pump design, clearances within the limits, surface finish etc besides other hydraulic factors. You did'nt give what is the efficiency as per your contract, but for horizontal centrifugal booster pumps 71% is a good figgure.
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Anonymous Poster (1); Codemaster (1); MrGeneRall (1); pritam (1); Unredundant (1)

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