Automation Functions and Characteristics in Rolling Mill Production

Automation in the steel rolling industry refers to the adjustment of control processes based on the detected values of on-site control objects and deviations from set values. It ensures that the output stabilizes within the specified range through predetermined adjustments. From an engineering perspective, process automation can be specifically understood as the utilization of automatic devices, electronic computers, and electrically driven mechanisms in various production processes. These components form a control system, maintaining various process variables at the desired set values. This coordination, under human supervision, ensures stable and high-quality production.

The goal of process automation is to enhance product quality, manufacture durable and exquisite products using limited resources, and achieve automatic operations in fast-paced working environments where human capabilities fall short. It liberates individuals from strenuous and monotonous manual labor, reducing susceptibility to human emotions and technical skill levels, allowing stable operation of the process. Automation can provide high-quality, stable, and reasonably priced products, offering greater potential for the development of production in enterprises.

The objects of automation in the rolling mill production process are electromechanical and hydraulic systems. Due to the small inertia, quick response, and control cycle requirements of 2-20ms, the control cycles for position control of the rolling mill system or constant force control of the hydraulic system are in the range of 2-3ms. Control of electromechanical equipment or process parameters should be less than 20ms. This is significantly faster, approximately 20-40 times, compared to process automation in industries such as chemical, light manufacturing, refining, and metallurgy, where thermal parameters are the main focus. Rolling mill automation demands fast updates of control information between control stations, especially in the hot strip mill's rolling zone, where multiple closely related control functions interact, sharing input and output modules.

Therefore, a rolling mill automation system requires technical features with high-speed control and communication capabilities. Typically, a fast distributed computer control system is employed, continually developing powerful software based on this system to create a computer control system suitable for the rolling mill production process. The rolling mill automation system, as a computer-centered automation system, enables real-time control and supervision of the rolling production line. With numerous control tasks, such as position control of nearly 10 electromechanical devices, over 20 hydraulic position or constant pressure controls, various thickness and shape automatic controls, main speed control, active roll tension control or tension-free control, and six active roll height controls in the example of a hot strip mill, there are almost 55 circuits requiring control. Therefore, the system necessitates a structure with multiple controllers and multiple processors within each controller. In the entire rolling mill automation system, the automation systems for hot and cold strip mills are complex due to the numerous controlled variables whose results ultimately affect the deformation zone between the rolls and the workpiece.