High pump vibrations...
High pump vibrations...
(OP)
I have been experiencing high vibrations in our one of our auxiliary boiler feed pumps since a recent rebuild. It is an Ingersoll Dresser 2WX8A horizontally mounted multi stage pump, with a Schrodahl ARV. The vibrations are normal for the pump, in the .450 in/sec range when the pump is in the recirc mode, once the pump reaches full load and the recirc flow drops to zero, the vibes jump up to .750 in/sec. The normal discharge pressure is between 1150 and 1250, flow is around 50 -60 KPPH. The recirc flow is 68 gpm at its max and the vibes move up when the main flow gets above 50 KPPH and the recirc gets below 5 gpm.
The alignment has been checked and rechecked, today we tried adjusting pipe hangers to decide if pipe strain was a factor. Any other areas to look at to determine why the vibes change so much at the high load?
Thanks,
The alignment has been checked and rechecked, today we tried adjusting pipe hangers to decide if pipe strain was a factor. Any other areas to look at to determine why the vibes change so much at the high load?
Thanks,





RE: High pump vibrations...
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Eng-tips forums: The best place on the web for engineering discussions.
RE: High pump vibrations...
=====================================
Eng-tips forums: The best place on the web for engineering discussions.
RE: High pump vibrations...
The pump is a single speed, electric motor for a driver.
Thanks,
RE: High pump vibrations...
• Run-out on the rim of the coupling hub should be less than 0.003".
• Run-out on the face of the coupling hub should be less than 0.003".
• Thrust float will depend on the thrust bearing configuration. For a ball bearing, you want at least 0.002" and no more than about 0.008". The pump manufacturer may specify a tighter range. For a tilt pad thrust bearing, it could be as little as 0.008" or as much as 0.015" depending on the bearing manufacturer's recommendation.
• If you are not certain that the rotor was axially aligned to the volutes or diffusers, it might be a good idea to verify this.
•If the discharge pressure is normal, it can't be running with reverse rotation. But it is an easy thing to check.
•If there is a suction strainer, I would check to make sure it is not plugged up.
Any more details about what was found during the overhaul could help us understand what may be the problem.
Johnny Pellin
RE: High pump vibrations...
RE: High pump vibrations...
RE: High pump vibrations...
RE: High pump vibrations...
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