Relube Frequency of bearings

Goor topic. All those charts were intended to give some guidance and are drawn after succesive test resuls pass/no pass. There is no perfect formula, the practicioners wanted to guide users but all of them are based on using different greases. Therefore the recommendations have no correlation.

Expectant to hear the thought of bearing specialists

I am dedicated to desing automatic lubrication systems for more than 20 years and under my experience there isn't the exact formula due by different reasons one of them could be that the same bearing could be assambled in different industries with diferent environtments, so this element needs different grease quantities and re-lubrication periods. I always use a simple formula instead of the huge quantities you can find on bearing manufacturers catalogues or in lubrication systems manufacturers, where you find different results at the same problem. This formula was given by my mentor and it is contact surface x 10 micron of lubrication film every 5 minutes, then when you start the system you can adjust the frequency until get the optimal. Some years ago I was really worried about this subject but as it was impossible to have the solution I decided to use and just works. Formulas just help as a start race, but then you should adjust as what you see.

Joan Borregà
http://www.neubor.com

Hi Mark

Both above replies have good info,

The check on whether the system in use is performing correctly to sample the exit path for the used grease and check visually by microscope using WDA to establish the ratio of wear metal to oxidised lubricant particles.
At the lab with grease we often see ISO 23's in the particle count considered to be normal,
we adjust the grease flow on the results of the visual check and adjust until we are getting heat damaged lubricant particles but no significant metallic particles using the grease to the max without damage to the application

Regards Rob S

Hi Mark,

It is you who can measure that correctly. Bottom line is if your machines reach your scheduled maintenance or shutdown always is ok. For me, the best relube frequency is keeping the grease in optimum level. For example, if you know that bearing consumes 2.5cc in 24hrs operation you need to inject not 2.5cc in one day but 0.625cc every 4hrs. Of course you need automatic lubricator to do that.

Regards,

Danny