Analysis of longitudinal buckling in temper rolling

Abstract

In temper rolling, shape defect called "longitudinal buckling" sometimes appears, which is wrinkles like washboards. The direction of the crest line of the longitudinal buckling is parallel to the rolling direction. In this study, the analysis of the longitudinal buckling is performed using the elementary theory of buckling. First, we calculate the material-roll contact ratio by the Hertz's formulae. Next, we calculate the stress distribution in the material at the roll gap using the punch pressure in indentation by Prandtl. Furthermore, we calculate the wavelength of the longitudinal buckling by the elementary theory of buckling. We find that the wavelength of the longitudinal buckling calculated from the analysis almost agrees with the wavelength of the longitudinal buckling in the literature obtained in the experiment. We conclude that the method of analysis is valid, and that the cause of the longitudinal buckling is the surface roughness of the roll.