Contact stress analysis of a spur gear using Lewis and Hertz theory

Abstract

The rapid development of automobile and aircraft industries has made applying gear technology necessary. Gears offer the benefits of efficiency, reliability, simplicity and a higher speed ratio with power transmission. However, they cannot transmit power over a long period, are more expensive when compared to belts and chain drives and requires continuous lubrication. They are used for transmitting high load in gear tools. The gear teeth fail when subjected to a high load beyond a certain limit. A deciding factor in gear design is the amount of stress developed on the contact surface of the mating gears. This paper deals with contact stress analysis of spur gear. The theoretical analysis was presented in this paper with the aim of contact analysis of the rolling bearing based on the Hertz and Lewis equations principle. A 3D Finite Element Method is established to calculate the stress between the contact surface of the structure. Contact analysis was performed using ANSYS Workbench software to figure out the deformation and optimum stress developed on the teeth of the gear. Simulation results indicate stress distribution at the contact surface of the gears with a maximum value of 144.82 MPa, while deformation stands at a maximum value of 0.01676 mm. The safety factor shows a maximum level of 15, indicating the safety of the design.