Posts by: Tim Sorensen

Soft Foot! Or Are You Just Pulling My Leg?

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By on February 12, 2018

It’s no joke that many machines operate with high levels of vibration due to soft foot.  These same machines often have a decreased life span due to this condition. Soft foot is a condition that should be eliminated during the precision shaft alignment process, if you’re performing proper alignments at all.  This condition can manifest […]

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I Just Changed My Motor Bearings and They’re Bad Again!

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By on December 20, 2017

When performing vibration analysis, it is observed that machines with VFD drives have a more frequent occurrence for changing motor bearings.  If you’ve been diligent in the installation and maintenance of these machines, ensuring the alignment and balance are within specification and the bearings are properly lubricated, but still have frequent bearing failures, it may […]

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Shock Factor and SFI

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By on November 1, 2017

For years, vibration analysts have depended upon the ISO Vibration Severity Chart for the determination of machinery health.  Typically, this chart provides a level of certainty that would allow the analyst to look at the vibration levels, and if acceptable, move onto the next machine for analysis.   Some defects are determined in the waveform […]

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Using Bearing Defect Factor for Gear Defect Detection

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By on October 12, 2017

Bearing defect factor is a culmination of two technologies used for shock detection.  DEF is designed as an indicator for bearing defect detection, but can also be valuable in the detection of gear defects. Why is DEF significant? In the following data set are displayed Overall Vibration Velocity, Overall Acceleration, and Defect Factor.  The Overall […]

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One Resolution to Motor Resonance

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By on September 28, 2017

A customer was experiencing high levels of vibration on one of the HVAC motors. The cause for these high vibration levels was determined to be resonance. Resonance of this motor was seen in the vibration spectral data and was confirmed onsite with a bump test. This motor was not VFD driven and therefore the machine […]

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