What is the difference between Ultrasensors and Acoustic Emission (AE) or Vibration Sensors?
A3. These are two completely different technologies. AE or vibration sensors record the vibration of a bearing that occurs when some kind of failure occurs. For example, if the lubricant supply to a ball bearing is interrupted a spall can occur in the raceway. This causes whole bearing to vibrate or emit an acoustic signal. AE and vibration sensors pick up post failure signals. The ultrasensor technique measures the oil film directly. This means it can give an early warning of lubrication failure before any damage to the bearing occurs. One is a passive technique (just listening) and the other is an active technique (shouting and listening). This means that the ultrasensor method will work on a stationary bearing (whereas AE will not).
