Lubrication related bearing failures account for 60% to 80% of premature bearing failures. These bearing failures are due to either lack of lubrication, under lubrication, or using the wrong lubrication for a specific application.
Using an ultrasound instrument to listen to the bearing while applying lubricant and watching the decibel level, one can determine when enough grease has been applied and when the threshold where over lubrication has begun.
The source ofultrasound with bearing lubrication is friction. When there is an increase in friction, there is an increase in the decibel level or more noise. When a bearing is in a lack of lubrication state, there is an increase in both friction and noise. When using the ultrasonic instrument, the inspector listens to the bearing and watches the decibel level on the instrument. As grease is applied, there is less friction and less noise.
If you currently use Ultrasound to Insure your Bearings are lubricated effectively please post your comments and advice.