Vibro-Acoustic Characteristic of A Self Aligning Spherical Journal Bearing due to Eccentric Bore Fault

Self aligning spherical journal bearing is a type of plain bearings which has spherical surface contact. This type of bearing can accommodate a misalignment problem. The journal bearing faults degrade machine performance, decrease life time service and unexpected failure which are dangerous for safety issues. Surface vibration (SV), airborne sound (AS) and acoustic emission (AE) measurements are appropriate monitoring methods for early stage journal bearing fault in low, medium and high frequency. This paper focuses on the performance comparison between SV, AS and AE measurements in the self aligning spherical journal bearing with normal and eccentric bore faults. The dynamics of the bearing is studied to gain the generation and characteristics of SV, AS and AE, which allow the extraction of useful information for diagnosis. The results of SV, AS and AE experiments especially for selfaligning spherical journal bearing due to eccentric bore fault indicate that the spectrum can detect significantly distinct between normal and faulty bearing. The statistic parameters show that RMS value and Peak value for fault bearing is higher than normal bearing. Spectrum of SV, AS and SE showed significant differences between normal bearing and eccentric bore bearing. Keyword: Self aligning spherical journal bearing, Fault diagnosis, Surface vibration, Airborne sound, Acoustic-emission, Eccentric bore.