Bearing vibration

Diagnostic procedures on bearing systems are an essential part of modern systems of preventative maintenance. Condition Monitoring Systems (CMS) are being used increasingly for machine diagnostics. Many of these systems are based on bearing vibration measurement. The systems are required to perform diagnostic qualitative procedures (envelope spectrum) and quantitative procedures (vibration velocity). Inobalt's Expert Vibro devices are capable of performing both types of procedure.

Different types of velocity sensor are in use. These have high cut-off frequencies and good levels of resolution. Expert Vibro devices can compute envelope spectrums from the time signals of velocity sensors. An envelope spectrum delivers detailed information on the state of a bearing. For example, the spectrum can reveal the state of the inner and outer rings, the bearing cage and the ball bearings. The ProfiSignal software and Vibro option enables users to portray and evaluate envelope spectrums.

The quantitative procedure converts the velocity sensor's time signal into vibration velocity. A Expert Vibro device is able to perform this conversion directly online. The vibration velocity is then usually monitored as a sum level.

Benefits of Inobalt products


  • Evaluation of vibration strength veff according to DIN ISO 10816
  • FFT analysis within device / frequency band monitoring
  • Evaluation of bearing damage diagnosis using envelope curve frequency spectrum
  • Monitoring of vibration levels
  • Intelligent recording within device
  • Visualization and analysis using time signal, trend spectrum, FFT cascade, and orbit and polar diagrams