A new method for preform dimension and influence of relevant parameters in the gear forced throughfeed rolling process

Abstract

Gear rolling process is an advanced forming technology in which the rolling die extrudes the preform material to flow plastically and finally form desired gears, and the preform dimension has a decisive impact on the quality of the final formed gears. To further explore the influence of tooth-tip defects on the tooth height of the formed gears in the forced throughfeed rolling process, and ensure the quality of the formed parts, a new computational method for the preform dimension was firstly proposed. A growth coefficient model based on the effective top circle of the formed gears was also given. Then, the dependence of the effective top circle size in regard to geometric parameters and material of the formed gears such as the number of teeth, module, and pressure angle were explored by the established model and finite element analysis (FEA). Finally, the experimental results were displayed to verify the proposed computational method and theoretical model. The results show the growth coefficient increases with the increase of the number of teeth and module, and decreases as the pressure angle increases. Moreover, the material with better plastic deformation ability contributes to improving the growth coefficient. Additionally, the proposed new method and theoretical model for preform dimension calculation could be adopted in the gear rolling.