Analysis Of Gear Hole-bearing Outer Ring Contact Stress With Tooth Root Stress And Life Prediction

In engineering practice, contact phenomenon seen everywhere, the force between objects in the transfer always must through the contact. Mechanical movement can not be transferred without the contact pressure, especially in the areas of mechanical transmission where three-dimensional contact widespread. Parts failure caused by contact problems has been a subject of concern of people. One on the contact problem, it attracted experts and scholars at home and abroad universal attention.KPBV150 planetary gear reducer ran fracture after two years which used for broken equipment in a company. Damage occurred in the second-class planetary transmission, a planetary gear cracking. First, the material defect and relative sliding caused microcrack on the surface of planetary gear hole and then extended to the tooth root, leading to cracking of the planetary gear under the loads, from the sun at the same time round, planet-frame, the gearbox and other parts of deformation and fracture. Then, the overall gearbox failed.This paper is mainly about the analysis of gear hole-bearing outer ring contact stress and tooth root stress and life prediction. KPBV150 large-scale planetary gear reducer failure analysis for engineering background, with engineering drawings, made structural analysis, stress analysis and correlation calculation. CAXA, Pro/E were used for modeling, in the analysis software ANSYS, strength analysis of the failure part were made, including contact stress analysis between the bearing and gear, as well as the bending stress analysis of the gear tooth root. Through the above calculation of the actual project works and contact stress analysis, this paper made a relatively clear exposition on the contact problems based on ANSYS. The life prediction and designed safe factor of the damaged gear was evaluated, the critical crack size was derived, all of which gave practical guidance for engineering.