I just wanted to relate a success story, although it is still not completely finished.

I implemented thermal routes in the plant I was hired into about 2 months after being here. I have found about 40 problem areas in the last 5 months that I have been doing it. However, every time we have found a hot motor, we simply replaced it, and often received little information back from our rebuild shop.

Last week I found a 1 hp motor that I have been watching for 2 months at 180 degrees F. It has increased over the last 2 months from 140 to 160 and to finally 180. I was planning on having it swapped out, but I waited because we were going to have our first vibration route performed by a local contractor this week. Vibration analysis pointed us towards the drive end bearing having a serious defect.

Anyways, just excited about combining thermal with our new vibration analyses.

As to finishing the RCA, we will be inspecting the pump it was attached to when the motor is swapped. (directly driven small oil pump)

This message has been edited. Last edited by: Jack J,

Hello Jack,

Thanks for sharing your success story with the forum. The combination of thermal and VA certainly seems to have helped make a difference on your plant. I know you said the story isn't finished yet and I wondered what your next steps are going to be.

I would probably focus on some detailed RCA's and ask why my motors are getting hot, why are the bearings suffering from defects etc.....

You may find some common causes associated to all the 40 problem areas you mentioned, that if you could eliminate altogether would result in no more failures of that type. The common causes could be associated to the design, the installation, the storage, the operation, the type of maintenance etc...

Good luck and keep us updated on your progress.

Cheers Gary

Whenever I see a problem with bearing used in electrical motor applications, the first thing that pops up in my mind is electrical damage. All too often an electric motor design or installation results in stray currents across the bearing races. This comes from improper grounding or design and results in electrical microarcing from continuous current leakage. This microarcing builds up over time and weakens the raceway surfaces, making them brittle.

The fluting you see in bearing damage books is the advanced (or classical) form of electrical damage. Highly loaded bearings with electrical damage in can result in spalls, compromised grease, or other advanced damage mechanisms.

I happen to be the industry expert on forensic analysis of bearing electrical damage. The main tool for this analysis is the scanning electron microscope.