Serious pump problems
Serious pump problems
(OP)
Hello all. I am new here and was wondering if you could help me out. We have a "brand new " installation of 3 VFD operated, 600hp End Suction Horizontal 12 x 14 Centrifugal pumps rated at 5780 gpm @ 233 ft. Since day one they have vibrated excessively(.80 to 2.5 in/sec RMS). I thought the manufacturer was Holy Sh**! or Shut it down! since that was usually called out when it ran. The manufacturer is saying that it is vortexing that is causing the vibratione even though there was 18+ ft of head and minimal flow at the time. We had a detailed (expensive) vibration analysis done by a well respected company. They indicated that the shaft was wobbling due to inadequate effective stiffness in the bearings and a poor structural strength of the base. We can't use the pumps (going on 2 years now)and the manufacturer is obstinate about the cause. My question is am I missing something or have the laws of physics been suspended regarding the vortex issue.
Has ayone run into a situation like this and if so what was the resolution.
Thanks in advance for you time.
Has ayone run into a situation like this and if so what was the resolution.
Thanks in advance for you time.





RE: Serious pump problems
RE: Serious pump problems
RE: Serious pump problems
Dik
RE: Serious pump problems
You have not said anything about the pump arrangement. The pump arrangement is critical. It is possible that you may have flow currents in the wet well that are causing a problem.
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RE: Serious pump problems
And by the way, love your handle.
RE: Serious pump problems
Schematic would be a help. Also answering above question about type of pump would help.