Motor bearing temperature

It sounds to me like you are temporarily increasing the heat transfer by injecting material (grease) into an area that is normally void due to the motion of the shaft and bearings. Consequently, a little additional heat is drawn outward to the metal casing. I would imagine that this effect will disappear after a few minutes due to the displacement of the newly injected grease by the motion as described. To determine why one side rises more, in temperature, than the other side you would need to look at the temperature distribution and construction of the motor. I would suspect that it is air cooled and the air is drawn into the motor on the side that is cooler.

Stop Greasing,

because you are overgreasing, I have experenced motor burnt or overheated due to excessive grease caused restriction in airflow or act as insulation in-between coiles & cooling meadia in case of water cooled motor.

I bet you will find over doze, if you dismantle bearing housing.

Hope its help,

Regards

AMateen

You are the most probable correct diagnoser.

In a greased bearings (or even in a few sealed oiled circuits), the lubrication should not be tightly packed.

Usually the grease is filled only to about 70-80% of the free space. In our machines we provide the greasing point on bottom, and at the angle about 75⁰ or so there is a relief hole. So pump till grease comes out of this hole is the recommendation in our machine manual.

This allows the grease to move around to lubricate. Over packing of grease makes the grease to obstruct the rotation of the rollers and are more likely to act as brake than lubrication.

Also ensure complete cleaning of the previous grease

And avoid brand/ grade mix-ups.

We are doing greasing as per the schedule specified in the nameplate detail of the motor.

You said the temperature rises abnormally

Then it dies down after how much time ?

You are greasing a live (rotating motor) bearings, Sorry that was the critical infrmation I missed.

In this acse effect of churning will be too much. I infact have not had any experience with the live rotating motor or for that matter except a few things any thing greased under live condition.

In enclosed casings, the risks are just a bit too high. We recommend for our machines the greasing, in the few cases we have, in idle condition. Of course that does not include open gear greasing.

PS: checked the net, adding the link , check the last portion http://www.reliabilityweb.com/art06/motor_greasing.htm

also

http://www.machinerylubrication.com/article_detail.asp?articleid=339

If you look at the bearing/journal from end on, and consider a clockwise rotation, then exaggerate the clearances in your view, you will see that the shaft will be closest to the bearing in the lower right quadrant when under load. If you increase the pressure from using to much lubricant, the hydraulic forces opposite will force the shaft even tighter against the bearing. Back off on the amount of grease and allow the design clearances to be effective.