Dian-Hua Zhang

Through taking the cold rolling process as the research object, the three-dimensional finite element model of the strip rolling process is established by using ANSYS/LS-DYNA software. The actual rolling product data has strong consistency with the finite element simulation results. The rolling process is dynamically simulated, and the distribution curves of important rolling parameters such as equivalent stress, control efficiency coefficient, transverse rolling pressure, lateral thickness and work roll deflection is obtained. Based on summarizing the influence of rolling parameters on rolling deformation, the research results of this paper can play an important role in the actual rolling process control. The research results have certain guiding significance for the development and optimization of the rolling control system.

During the flatness control process, there are frequently some uncoordinated regulating behaviors in the flatness actuator group. This has a bad influence on the flatness control accuracy and the flatness control efficiency. Therefore, a collaboration strategy based on conflict resolution for the flatness actuator group has been proposed in this paper. First of all, the feature of flatness measurement value is extracted through establishing the actual flatness condition discriminating factor. After that, the coordination cooperation that is appropriate to the actual flatness condition is developed for the flatness actuator group. Finally, the optimal adjustment of the actuator population is solved by the coordinated algorithm of Topkis-Veinott and genetic algorithm collaborative optimization. The collaboration strategy proposed in this paper has been successfully applied to a flatness control system of a 1450 mm five-stand cold rolling mill.

Based on comprehensive consideration of elastic and plastic deformation of both strip and work roll, an online rolling force model for tandem cold rolling mill has been developed by numerical integration method in this paper. According to the load equilibrium equation and the boundary condition, the vertical stress of every unit can be obtained. The rolling force in the plastic deformation zone can be calculated via the sum of vertical stress of every unit, and the total rolling force can be obtained by summing rolling force of elastic and plastic deformation zones. In addition, the suitable mathematic models of friction coefficient and strip deformation resistance were also established. In accordance with the coupling problem between the flatten roll radius and rolling force, the iterative procedure by computer was built. This rolling force model has been applied to a 5-stand tandem cold mill and the relative error of rolling force prediction is within ±4.1%, which proves the model is accurate and meets the requirement of online process control.