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Hi Kristine, 

Thanks for your response. Our collection parameter for route collection on this pump is an Fmax of 100 orders and 3200 LOR with 4 averages. which, as you say, could be low enough that certain sideband peaks are melted into a haystacking pattern. It's strange that the sidebands became clearer over time, likely as the wear became more severe.

Hi Brayden,

You have a great discussion going here. I just wanted to add that, from a vibration analysis perspective, bearing failures can cause high spikes that will then go away as time goes on. Basically, there isn't enough material left for the balls to jump or hit the cage and amplitudes will actually begin to fall before failure. Also, your line resolution may be contributing to the haystack and odd placement of sidebands and peaks. With a Hanning window, peaks that are on the edge of a bin will be averaged across both lines. I realize that doesn't help now, but it may be beneficial in the future to increase your resolution and take another reading if you see haystacking or strange harmonics.

Good Luck,
Kristine Moore

Hi Brayden Olafson,

Quite unfortunate about your 'small pump bearing case failure' experience. 
Most of the time, Fragments of flaked material or other hard particles may have become trapped between the case and other rolling elements, preventing the latter from rotating around its own axis. This leads to case failure.
It's easy to imagine that when the bearing gets stuck to the case and stops spinning it creates friction which puts continuous stress on the casing. And since most casings MOC were designed to absorb lesser stress, failure stands at imminent, which would damage motor over time. 
I will suggest disassembling this motor to evaluate damages and plan for adequate repair or spare replacements.

Good luck!

Celestine
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