Hi to All
We are facing one vibration issue in sea water intake pump. The pump is vertical pump driven by motor and the RPM is 740. The vibration issue started before 6 months. The pump vibration was varying from 3mm/sec to 8 mm/sec RMS. The vibration is high in one direction (towards flow directions). The vibration in other direction of the pump is normal with minimum variation up to 2.5 mm/sec.
Initial there was minor abnormal sound from the motor Non drive end bearing with bearing defects in the vibration spectrum. The motor solo run was tested and bearing replaced.
The pump vibration shows variations at 3X. Upto 10mm/sec along with flow direction.Initially misalignment was suspected and also to review the gear coupling for any abnormalities.
The alignment was checked and found severe misalignment. The coupling was found ok. The runout of the coupling also within normal.
The equipment started again and found same pattern with high vibration . Again alignment was out and decided to take the pump out and checked completely. No notable abnormalities. However the rubber bearings were replaced.
The pump started again and the problem still persist. Kindly share your ideas.
Hi to All