Adhesive Wear Models for Helical Gears under Quasi-static and Dynamic Loads

Abstract

According to the equivalent contact model of tapered rollers in opposite orientation and Archard's wear formula, a new adhesive wear model for helical gears is proposed in this work. Face loads are firstly determined by the time-varying contact ratio and bending-torsion-shaft coupling dynamic model of the helical gear drive, and then the tooth pressure and the sliding distance are evaluated based on the equivalent contact model and Hertz's theory. Thereafter, the wear depth is computed under quasi-static and dynamic loads. The presented method is verified by the comparative wear depth curves from this work and the published papers, and effects of the major geometrical and working parameters on the wear depth are investigated. The results show that larger wear depths are generated at the root and the tip, while the wear depth at the root is larger than the one at the tip, and that it trends to zero at the pitch line. From front transverse plane to rear one of the driving pinion or driven gear, the wear depth of the pinion becomes smaller whereas that of the gear turns larger. However, the wear depth of wide-faced helical gears trends to a uniform along face width. Additionally, the parameters analysis show that the wear depth decreases as modules, transmission ratios, face widths or input torques are increased, while helical angle or rotational speed variation has little influence on wear depth reduction. It is also indicated that accurate determination of the wear depth and rational match of the geometry and working parameters are valid in gear surface quality and transmission performance enhancement, and to wear resistance in engineering design.