Rollers and inner ring raceways of axlebox skf bearings, as well as toothed wheels all generate specific dynamic frequencies, which can be detected and analyzed with additional knowledge of certain geometry data and shaft speed. Minor geometry bearing differences such as spalls can also be identified very early through the analysis of the generated frequency spectra.
Traction motors and gearbox components such as china bearings and toothed wheels may also be monitored, as well as shafts and couplings, using vibration sensors as part of the bogie condition monitoring system. Gearbox oil level and temperature, and more recently, oil condition may also be included in the bogie condition moni-toring system or may be monitored in a stand-alone mode. Vibration signatures from propulsion components vary, depending on the actual traction effort applied. Consequently, information about the train speed and load has to be considered in the data processing, together with certain geometric parameters and the gearbox ratio.
