Hi,
I give you a few points to consider regarding the situation:
1. Vibration Analysis: The initial increase in axial vibration and the presence of a broad base on the harmonics might indicate potential issues such as misalignment, imbalance, or bearing wear. The fact that this condition persisted for an extended period could suggest that it was a developing issue.
2. Vibration Reduction: The subsequent decrease in vibration and the removal of the broad base may suggest that the issue has either been resolved or mitigated. This might occur due to wear stabilizing, realignment, or operational adjustments.
3. Plain Bearings: Since the fan operates on plain bearings, it is crucial to ensure that there is adequate lubrication and monitoring of wear. Any changes in lubricant properties can also affect vibration levels.
4. Comparative Spectrum Analysis : Comparing the attached spectrum data from both conditions will provide insight into the frequency components and help identify the root cause of the initial rough condition. Pay close attention to specific harmonic frequencies and their amplitudes.
Best regards,
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Mahad Bouh Doualeh
SGTD
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Original Message:
Sent: 08-27-2024 23:28
From: Luis Eugene Tibre
Subject: is this a case of resonance?
Dear all,
i would like to ask your expert opinions. We have a major fan and suddenly its drive end axial vibration (3AV) increased to rough level. i observed broad base on the harmonics, This was the condition the whole of July 2024. Now as of this writing, it has decreased and the broad base is also gone. In addition, the fan runs on plain bearings. I have attached screenshot of spectrum when it was rough and another when the vibration decreased. i have also attached a mab file from the month of July- august 2024.
Thank you very much
#Vibration
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Luis Eugene Tibre
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