Analysis of exerted stresses of final drive in MF 285 tractor by Theoretical and Finite Element Method (FEM)

Abstract

Gears is a rotating cylindrical wheel having tooth cut on it and which meshes with another toothed part to transmit the power or torque.. In this investigation, at first, bending stress and contact stress between sun gear and planet gear tooth were determined using of Lewis and Hertzian equations. Afterward, a 3D model of final drives gear was investigated via FEM method. According to the obtained results, maximum of bending stress and contact stress occurred in Gear 1 and low status of helping gear, according to the results that given in the table 3, maximum bending stress using of theoretical and FEM simulation methods were obtained 918.62 Mpa and 951.82 Mpa, respectively. Also, maximum contact stress in same status using of theoretical and FEM simulation methods were obtained 2952.71 Mpa and 2903.20 Mpa, respectively. The percentage difference between the theoretical and FEM bending stress results and contact stress results are of average 3.48% and 11%, respectively, which are still acceptable. As regards, some parameters are ignored in theoretical calculation such as: radial forces in Lewis equation and tangential forces in Hertzian equation, FEM simulation results are acceptable than theoretical results.