Material optimization of gear and pinion for planetary gearbox

Abstract

Gears are the important element of a mechanical system, which are used for variation of speed and power, failure of even a single tooth of a gear will make the machine to stop. Hence our aim is to strengthen the gear which is a key element of gear box. At Dynatech Engineering. Co. Ltd. due to catastrophic failure of gear teeth, the problem of gear teeth deformation occurred. Dynatech Engineering Co. needed to suggest appropriate gear material by considering its strength, cost, hardenability and machinability, due to past history of gear teeth failures. The materials utilized for pinion and gear are EN24 and EN8 respectively. The material properties and costing of pinion and gear material were studied, and standard gear materials were identified from PSG Design Data Book. The material sorting is done on the basis of availability, cost and strength of the material. We studied different material selection methods like Weighted Point Method, TOPSIS, COPRAS, ELECTRA and VIKOR Method etc. From these methods Weighted Point Method (WPM) is selected for material selection and its result validated by TOPSIS Method and COPRAS Method. The material is selected by studying above method. On that material we did the finite element analysis and we also did analysis on currently used material in Dynatech Engineering co. The input parameter required for analysis provided by company such as module, teeth on pinion and gear, operating temperature and torque on which it is operating etc. The analysis is done by using the software ANSYS 15.0. From the result of it is concluded that the selected material have less deformation and stress during the operation at the top of the teeth as compare to the existing material.