Bearing regrease maintenance 1

[npower0073]

I want to ask what is the best approach on motor bearings maintenance. Specifically it is better to regrease by adding grease or open the end shield of the motor and change the hole quantity of grrease?

 

[sreid]

Unless the motor has zerk fittings or grease cups, the bearings are usually sealed for life.

 

[diskullman]

Try a single point lubricator, such as

http://www.lubesite.com

Many other brands available, even from Timken. These lubricators feed grease automatically as needed, no underlube or over lube problems

Russell Giuliano

 

[electricpete]

Assuming this doesn't have shielded bearings, and you want to regrease it manually (rather than install a lubricator), the typical recommended approach by SKF is to relubricate by adding grease up to three times, and then open the machine, remove the old grease, and replenish.

In practice, opening a machine to remove old grease is a lot of work and presents a big potential for contamination. Most users just keep on adding grease "forever". If the bearing housing becomes full (may be evident during greasing, may show up as housing that runs hot continuously), then it would be time to manually change out the grease. At our plant we would also change the bearings at that time.


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[rmw]

A bearing properly designed for re-greasing will have a spillover tube for the liquid to be expelled when the new grease replaces it. As greases work, the lubricating oils separate from the soaps (lithium, calcium, etc.) that carry the oil (the lubricant is the oil, the soap is merely a carrier) and the liquid will be forced out when the new grease is added. Regreasing recommendations normally state that grease is to be added until oil appears in the spillover tube then quit.

I'd have to dig for a while to find a reference, so I will leave that for you, but I have seen them.

rmw