Abstract
This work will seek to describe in its experiments on spur/helical gears the possibility of occurrence of each of the normal and synthetic gear tooth defects (pitting, wear, crack and surface defects). Monitoring during the experiments period has been focused on temperature, spectrometric oil samples, vibration, and AE were monitored continuously in order to compare and relate these techniques to the degradation of gears life. The experiments of this study will run on back-to-back gearbox test rig. It is built for purpose of the study, and it’s prepared to appropriate the ability of identifying early indications of probable failure. Oil analysis, thermal analysis, vibration analysis and AE are the main tools which will be used in parallel during the whole test. The results of this research showed a clear relationship between helical gear teeth defect initiation and AE activities in several operation conditions. And prevent the suddenly shock of the machine and find a technique to know the time remaining before the total failure of the gearbox.