Influence of asymmetric structure parameters on rolling mill stability

Abstract

Considering the asymmetric structure of a rolling mill system, a chatter model is established by coupling a rolling process model and structure model to describe the asymmetric vibration characteristics. According to this mathematical model, the critical rolling speed is determined by calculating eigenvalues of the characteristic matrix. Model correctness and validity are confirmed by an experimental observation of a 2030 cold rolling mill. On this basis, the effects of asymmetric structure parameters on the rolling mill stability are investigated with the help of the numerical approach. It is found that the influence of the asymmetric structure parameters on stability and critical conditions is significant. An optimal stiffness ratio and optimal mass ratio is determined, in order to ensure the best stability for the considered system. As the asymmetry in terms of the stiffness and mass becomes considerable, a modal conversion phenomenon occurs. This study serves as a contribution both for the mill vibration suppressing, and for mill optimization design.

Adaptive Fuzzy Vertical Vibration Suppression Control of the Mechanical-Hydraulic Coupling Rolling Mill System With Input Dead-Zone and Output Constraints

“…Especially for vertical vibration, a large amount of energy will be accumulated in a short time, which can lead to thickness fluctuations of the strip as well as the stripes on the surface of the rolled steel products, and even cause the damage of the equipment. To avoid the adverse effects caused by the vibration, the emergency method for the rolling mill vibration control is to slow the rolling speed down [8], [9]. However, the reduction of rolling speed affects the production efficiency and can not fundamentally solve the problem of rolling mill vibration.…”

Optimization design of a novel X-type six-high rolling mill based on maximum roll system stiffness

“…Considering the asymmetric structure of the rolling mill system, Huang [19] established a chatter model by coupling a rolling process model and structure model to describe the asymmetric vibration characteristics, and found that the influence of the asymmetric structure parameters on the stability and critical conditions is noteworthy. In [20], Ma et al established a structural optimization method for a new Y-type rolling mill, which can solve the multiobjective problem of more complex constraints in engineering.…”