NORMALIZED SPECTRA IN MONITORING OF ROLLING BEARING ELEMENTS

This paper deals in detail with the monitoring and fault diagnosis of rolling element bearings by use of the 'envelope' technique. It describes an extension of the technique by 'normalising' the frequency spectra of the faulty bearing with respect to the healthy bearing. This is shown to give much greater sensitivity to the detection of defect frequencies. Earlier work on a test machine was first used to adequately define the envelope technique. After successful demonstration on that machine, the technology was transferred to the main spindle of a milling machine.