Dear friends
recently i tested condensate ejecter pump as it is giving abnormal sound and i noticed too much sound and in the vibration spectrum i noticed peak at 8829rpm with the intensity of 80mm/secat motor NDE(pump rpm is 710).the same peak observed at motor DE, pumpin board also with with less intensity
can you give me the possible cause of the above observation

What is the running speed of the motor ?
Can you post a spectrum?
Is it belt driven?

Dave

thank your for ur response
here i am sending spectrum and the Motor running speed is 710 with regid coupling directly coupled to motor. i took the vibrations at motor NDE,DE and pump inboard.pls give me the remedy for the above problem

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There appear to be some sidebands around the big peak. Zoom in on them and determine their spacing. The spacing will tell you the rpm of the component causing the big peak. You might want to look at these spectra in acceleration and try to identify the big peaks as part of a set of harmonics. I would also want to look at the autocorrelated timewaveforms in acceleration and PeakVue.

Is this a sudden onset or on-going problem? If it is a truly rigid coupling (no flexibile element, no gearteeth, no grid) then alignment must be almost exact.

Hi Apparao,

What is the pump installed orientation? I suppose based on the info you've given it must be a vertically installed submersible pump. How many vanes does the impeller have? Do you have vibration level trend on this pump? 80 mm/s is severe for a pump. What does the noise sound like...grinding sand or rattling. Do you have pressure gauges...is the indicator/pointer steady or fluttering?? If possible check the phase balance and bearing temperature of the motor.

Cheers...Rajan Muthukrishnan

Helo friends
yesterday i check this pump motor solo run
vibrations are good.This is a horizontal pump,over hung.It is a gearcoupling , i noticed on motor DE side gear teeth got sever damage, the pump and motor connected with a distance piece(to the ends of this piece gear couplings connected).I asked to replace gear couping and let me see in the next startup.
Thank you rajan for ur response and pls send ur yahoo mail id so that i can be touch with u and i can share in case of emergenciec

Hi Apparao,

With DE gear being worn, you need to ensure the alignment is set to spec, as Danny suggested. More so, check what else could have contributed to this wear, other then the alignment you could possibly have loose anchor bolts and/or weakened grouting/foundation; look for signs of crack to indentify root cause. BTW good feedback on your findings.
My personal email - rajsha11@sympatico.ca

Regards...Rajan Muthukrishnan