Numerical methods for evaluation of service life of gear

Abstract

Abstract The service life of mechanical parts, of which the gears are most important, is influenced to the greatest extent by defects occurring as cracks. In case of cracks the most important stage is the initiation and propagation of short fatigue cracks; further, the propagation of these crack up to their critical and/or permissible length also must be taken into account. As these are quite different areas we have introduced into calculations a completely new factor, i.e. the gear stress intensity factor Z . On the basis of the factor Z we have developed appropriate models, e.g. the programe STATFAG which ensures calculation of the service life of gears with and without cracks.