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RE: [MW:3891] What is NPSH?

By Materials & Welding

Please find answers as below

 

Regards

 

K.L.Pai

 

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of prashant pansare
Sent: Thursday, December 24, 2009 2:59 PM
To: mat wel
Subject: [MW:3889] What is NPSH?

 

Dear All'
I' ve to inspect centrifugal pumps for (chilled water) as per API 610.
I m familiar with all the inspection stages,but I want to know more about NPSH test.
A) NPSH test to be done at 5 points 1) zero flow 2) min. flow 3) in between min. & rated flow
    4) rated flow & 5) max. flow. is it correct?

 

NO. NPSH test is done at one point at 3 percent of the head. Pump manufacturer is right agency to guide you.


B) What r the parameters to be checked during above mentioned test?

 

 


C) What is to be checked during performance test?

 

Flow, pressure and power absorbed are to be recorded at five points as mentioned in A.

Then calculate efficiency and based on results pump characteristic curve. Efficiency should be more than guaranteed efficiency.


I need detail guideline,pl. help.
Thanx & Regds.to all.
PSP  

 


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