Design Optimization of the Driving Shaft of a Hammer Feed Grinder Base on the Response Surface Method

Abstract

Abstract. Taking the driving shaft of a hammer feed grinder rotor system as the research object, the static calculation and modal analysis were carried out by ANSYS Workbench software. The results show that under actual working conditions, the maximum deformation of the driving shaft is 0.437 mm, which occurs at the end of the pulley-mounted shaft section. The maximum stress on the driving shaft is 210.91 MPa, and the stress is mainly concentrated on the shoulder of the left shaft section matched with the bearing. The stress values at most other positions on the driving shaft are below 23.435 MPa. The first-order natural frequency of the driving shaft is 504.98 Hz, and the first six orders of natural frequencies are much higher than the excitation frequency of the hammer feed grinder (58.33 Hz). The driving shaft has small deformation and good dynamic performance, but there is a problem of local stress concentration. Therefore, the response surface method was used to optimize the parameters of the driving shaft. The diameter and length of the pulley-mounted shaft section on the driving shaft were selected as design variables, and the maximum stress value was taken as the optimization target. After the optimization, the diameter and length of the pulley-mounted shaft section are reduced from 30 to 28 mm and from 199 to 170 mm, respectively, and the maximum stress value on the driving shaft is reduced from 210.91 to 174.41 MPa. Finally, static calculation and modal analysis were performed on the driving shaft after the parameter optimization. The results demonstrate that both the strength and stiffness of the driving shaft are sufficient, and it does not cause resonance in the working process, indicating the successful optimization of the driving shaft parameters. Keywords: ANSYS Workbench, Grinder driving shaft, Model analysis, Parameter optimization, Response surface method, Static calculation.