ANALYSIS OF SPUR AND HELICAL GEAR IN PORTAL AXLE GEAR BOX USING FEM

Portal axle or portal gear are an off road technology where the axle tube is above the center of the wheel hub and where there is a reduction in gear box in the hub. A portal axle unit is installed between the wheel and the axle shaft to give higher ground clearance to the vehicle. Excessive bending stress and contact stress causes the tooth breakage at root fillet and pitch point of the gear. This project deals the bending and contact stress of spur and helical gear in TATRA off road vehicle. Lewi’s and Hertz's equations are used to calculate the bending and contact stress theoretically. The analysis was performed on three different configurations such as without, with one and with two idler gear for spur and helical gear and compared the results. The gears are modelled by SOLIDWORKS and analysed by ANSYS workbench software. Theoretical and FEA stress values are compared for spur and helical gear. Among these two gears, spur gear shows the minimum bending stress and contact stress.