Color of motor bearing grease
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It’s a new 15KW motor that experienced excessive vibration, so the bearings were removed and replaced, and lithium-based oil was added; this oil is dark red in color. After restarting the motor for half an hour, the vibration persisted, so the motor was taken apart again and it was found that the lithium-based oil inside the bearings had turned white. I wonder whether the color change of lithium-based oil occurs when the temperature rises – after all, the temperature doesn’t rise that quickly after just half an hour of operation – or is it due to poor quality of the oil?
It’s probably a problem with the motor – such as three-phase imbalance, or there might be an issue with the bearings. It is recommended to clean the bearings or replace them with new ones.
I’m not quite sure what you mean by color change; I’ve never disassembled it in such a short period of time. As long as there’s no water inside the motor, there should be no problems. At most, the material might melt due to high temperatures. The vibration you mentioned is probably not caused by the motor bearings; maybe the coupling isn’t adjusted properly, or the foundation bolts aren’t tightened enough. Motor bearings generally don’t wear out that easily. Besides, your motor is new
It’s likely a quality issue with the motor; contact the manufacturer to resolve it.
It is recommended that the property owner be precise – oil is oil and grease is grease; the problems described are vague, so how can others help you? Lithium-based greases contain a small amount of water, and there are limits to the operating temperatures at which they can be used. Therefore, increased bearing wear can cause a change in color, but it’s not clear whether it will turn white.
It seems the color might turn white, but it’s hard to tell at this point; you should ask the supplier of lithium-based grease
The main suspicion is that there is water in the grease; buy some new grease and add it.