Nonlinear Torsional Vibration Characteristics of Rolling Mill Considering Rolling Interface Lubrication Friction Effect and Parametric Excitation Available to Purchase

A dynamic model of the nonlinear torsional vibration in the main drive system of a rolling mill was established, accounting for friction torque obtained from the lubrication friction effect at the rolling interface and parameter excitation caused by the inclination of the universal joint shaft. The dynamic response of the nonlinear torsional vibration equation under the combined action of parameter excitation and external excitation was solved using the multiscale method, by determining the amplitude–frequency characteristics of the nonlinear torsional vibration. The influence of structural parameters, external disturbances, and parameter excitation on vibration behavior was analyzed. The results show that increasing system damping and friction torque parameter reduces the amplitude of nonlinear torsional vibration, while greater external disturbances increase it. Additionally, changes in excitation amplitude cause the vibration mode of the rolling mill to shift between periodic motion and chaotic motion. These findings provide valuable insights into the nonlinear torsional vibration mechanism and offer a theoretical foundation for further research and optimization.