hi all
i have vibration problem on my circulating water pump ( vertical pump, mixed flow, supply cooling water to condenser ).
Vibration problem was started at 19 January, motor current was fluctuated from 100 A to 95 A and followed by vibration fluctuation. Motor current and vibration fluctuation happened for 6 days, and since 25 January, motor amperage down to 95 A (steady) and vibration also steady in higher level. Operation department didn't notice any change in condenser vacuum. We have 3 Cooling water pump but this problem only on 1 pump. Vibration amplitude is dominated at 400 rpm (1 x running speed)
what might cause this phenomena, is it mechanical problem or hydraulic ?
thanks

regards
jasmine

WEll i would like more information before making an educated hypothesis. Honestly, the rule I would use, is if the amperage is going down (The pump working less) and the vibrations going up. What would affect both of those? Is it all wires that have a drop in amperage or just one?

If you can post all the information, a picture is worth a 1000 words as well.

Rob

It sounds like you have a relatively large condensing steam turbine (maybe for power generation). If the condenser is partitioned, I would consider a plan for a unit load reduction and then online condenser cleaning and inspection.

I would like to make a guess. Decrease in current reflects decrease in discharge from the pump. Check the pump shut off head if possible. It should have gone down. May be, wearing ring clearances have increased.
Vibmaster