Weight reduction of planetary gearbox pedestal using finite element analysis

Planetary gearboxes are widely used in machineries and machine tools to obtain high speed reduction. In this project the planetary gearbox used in winch application is analysed for weight reduction using finite element analysis. The analysis for weight reduction is carried out on two major components of the assembly, pedestal and planet carrier. As the manufacturers focused on weight reduction in the components without affecting the performance in the products in order to reduce cost and sustain in the market.

In this analysis the assembly of gearbox is constructed as solid model, the forces and torques are found using hand calculations and verified using Adams results. The model is meshed and finite element model is generated initially. The FE model is imported to Ansys and FE analysis is conducted by providing the forces and boundary conditions to the pedestal. The results of von-Mises stress and deflections are obtained for existing model, based on the results with size modifications three different models were developed and analysis is conducted without changing the loads and boundary conditions using the design constrains the results were refined. The material used is IS: 2062 Gr-A and compared its yield strength with the induced von-Mises stress and identified that the modified design is safe.

Based on the results of static analysis, a new model with the change of geometry without affecting the performance is developed with weight reduction. It was found that the proposed design of pedestal gives sufficient improvement over existing designs. The recommended weight reduction in pedestal is 40.8kg with 13.1% weight reduction.