Motor Bearing temp sudden increase

Once is plenty to post a question!

Motor bearing get high temp

Lack of lubrication/increase in friction

what is increasing in temperature?

the motor or pump?

Motor from 58C to 80C

Do you have continuous (supervisory) monitoring facility for the temperature of this motor bearing?

I could see the 'a gradual rise of temperature' even before the sharp rise. And after the rise to 80C, it look like to increase very gradually.

Has it settled and ran for some time at 80C or failed or you stopped?

In your graph, the vertical line should be time interval, right? What is the time interval between two lines, one hour or ...?

after temp increased it run for 1.5 hr and was stopped

1. Do you have continuous (supervisory) monitoring facility for the temperature of this motor bearing?

Yes.

2. In your graph, the vertical line should be time interval, right? What is the time interval between two lines, one hour or ...?

20min

On 9^th of this month you've posted this reply. In these three days, what is happening?

Did you run this motor again?

Did you dismantle and inspect this bearing? Was the bearing really bad? Since it has stopped (tripped) after 1.5 hours, there is less chance for the bearing to have failed. Some miner damages might have caused but may not be visible for naked eye.

Never the less the grease would make reasonable telltale like:

· Was there (adequate) grease?

· Was the grease in excess? This could be seen by the excess grease would have came out of its space and spilled/thrown around.

· If bearing/grease appears to be good, suspect the temperature pick-up for erroneous indication. Is it a 'thermo couple'? Does it have 'thermo well' or direct proximity to bearing (outer) race? If yes, does this have any chance to rub against rotary part of bearing (rolling element gauge)?

Please share your experience for possible mutual benefit.

Possible reasons could be: Bearing failure due to wrong type of lubricant; Change in viscosity of the medium you are pumping; Change in ambient temperature; Drop in voltage.

What you have to do is as follows:

You need to removed out all the old grease from your bearing as some of these grease is already dry up and form a layer of cake around it.

Replenish the bearing with a new grease. Do not over fill it with too much grease. Too much grease will cause the bearing temperature increase. Use the correct grease to grease your bearing.

The bearing is worn or does not have enough grease. The shaft is bouncing around in the loose bearing, causing the heating from extra friction. Try adding some more grease.

This happened to me with a blower in a furnace. I would run for say 2 minutes then it shut off. I called the air conditioner people and told them I think my bearings are shot on my blower and sure enough he took it out and it was that. A heat sensing device acted like a circuit breaker and cut the power. Bearing do not last forever.