The influence of rolling bearing clearances on diagnostic signatures based on a numerical simulation and experimental evaluation

Abstract

This paper presents investigations into the influences of bearing clearances on the diagnostic features of monitoring rolling-bearings. A nonlinear dynamic model of a deep groove ball bearing with five degrees of freedom is developed for numerical analysis under increased radial clearances which are due to not only the scenarios of bearing grades but also gradual wear with bearing service lifetime. The model incorporates local defects and clearance increments in order to gain the insight into the bearing dynamics under different fault cases along with clearance changes. Numerical results show that the vibrations at fault characteristic frequencies exhibit clear inconsistency with common understandings for different cases of increased clearances. This study highlights that it has to take into account the clearance effect, especially for the inner race fault, in order to avoid the under-estimate of fault sizes which may be indicated by the feature amplitude reduction.Keywords: roller element bearing; nonlinear dynamic model; radial clearance; Hertzian contact deformation; condition monitoring. The influence of rolling bearing clearances on diagnostic signatures 17Reference to this paper should be made as follows: Rehab, I., Tian, X., Gu, F. and Ball, A.D. (2018) MSc from the Taiyuan University of Technology. He has published over 200 technical publications in machinery diagnosis, signal processing, measurement systems and dynamic modelling. He has undertaken vibro-acoustic research projects of turbine machines, electric motors, internal combustion engines, reciprocating compressors, centrifugal pumps, hydraulic power systems, gearboxes and bearings. Recent research interests are mainly on power supply data and tribological behaviour analysis-based system diagnostics and monitoring.Andrew D. Ball is a Professor of Diagnostics Engineering from the University of Huddersfield, PhD from the University Manchester and BS from the University of Leeds. He is one of UK's foremost experts in the fields of machinery diagnostics, dynamic modelling, intelligent computation and vibro-acoustics analysis, with over 30 years of maintenance engineering experience. He is the author of over 300 technical publications in machine diagnosis, non-destructive measurement and related fields, and he spends much of his time lecturing and consulting to industry in all parts of the world. He has been the organiser of several international conferences in condition monitoring and maintenance.