### New Method of Determination for Pressure and Shear Frictions in the Ring Rolling Process as Analytical Function

Document Type : Research Paper

Author

Mechanical Engineering Department, Sharif University of Technology

Abstract

Ring rolling is one of the most significant methods for producing rings with highly precise dimensions and superior qualities such as high strength uniformity, all accomplished without wasting any materials. In this article, we have achieved analytical formulas for calculating the pressure and shear friction over the contact arcs between the rollers and ring in the ring rolling process for the material in general nonlinear hardening property. We have also asserted the best mathematical model to predict friction for rolling processes. The method we use is based on calculating the analytical stress distribution. In other words, by using of Saint-Venan principal the stress components are calculated as analytical functions. Once that is accomplished, the pressure and shear traction over the rollers are able to be analyzed. The crucial characteristics which set apart this study from other studies are the investigation of the effects of the speed with which rollers are fed, and resulting ring velocity. With normal and shear friction, those characteristics cannot be investigated by other methods such as the slab method, upper bound, etc. Also, results show the effects of material hardening properties, radius of rollers and thickness reduction under pressure, and shear friction distributions.

Keywords

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