Hello all,
I would like to know whether it is possible to identify metallic seal wear using vibration signal. What is the typical signature ? Wheather other parameters like bearing temperature etc are suitable?
Thank you
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Is this a pump shaft mechanical seal or something unusual? Changes in friction can be detectable with vibration and ultrasound emissions, but the background noise from mechanical, pulsations, and flow would probably hide or mask seal friction. Perhaps doable on a seal test rig, but unlikely on a real machine!
Walt
I tried to use vibration readings collected by portable from bearing housings of horizontal pumps to detect signs of mechanical seal failures. I had no success using the standard signal processing configurations. It's even more difficult with vertical machines. I used US in one case and it showed a much clearer indication but we do not use US that much anyways. So, I could not form an opinion with a wider variety of machines, operating parameters, vibration signal interference etc.
Regards- Ali M. Al-Shurafa
If the seal squeal excite a resonance then you can see the difference clearly and it does happen but it can't be guaranteed.
Thank you @Registered Member @Registered Member and @Registered Member for your comments.
I have seen some cases where envelope (vibration) and electrical signature analysis were used to identify seal issues.
https://www.pumpindustry.com.a...c-motor-driven-pumps
I think @Registered Member can provide details on ESA-based seal issue identification.
Akashri, your initial inquiry was concerning “metallic seal wear” and I was thinking more along the lines of a mechanical seal. Your pointing to content by MotorDoc (Howard Penrose) makes me think otherwise. Were you asking about the typical seal arrangements as might be encountered on a motor?
By the way some of the content by MotorDoc where he mentions detection of seal issues can be found in an old thread at https://www.maintenance.org/to...9#399590942963646579. Once there scroll down a bit to the content by MotorDoc.
John,
If you would please give me a call.
Talmadge
863-370-9039
If you would please give me a call.
Talmadge
863-370-9039
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I am very skeptical of detection of seal wear by motor current spectrum analysis. My skepticism extends to vibration analysis and other technologies, such as ultrasound, when hind-sight diagnosis is made my using other unreported tests/measurements, teardown inspection, or simple guesses. This is not intended to discredit the success of others or to discourage folks from seeking new methods, instruments and software for machine diagnostics.
Walt