So why did this bearing Fail?
It is a cylindrical roller bearing from the drive end bearing of a 3 phase Induction Motor on a VFD.
Clues in the video here
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Moisture in the lube
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Uninsulated bearing (fluting)
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Electrical fluting caused by leakage current from the VFD. The motor either doesn’t have grounding rings or they are so dirty that it created a conductive path to the bearings.
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