Research on roll profile electromagnetic control ability in optimal electromagnetic stick parameter

Roll profile electromagnetic control technology (RPECT) is a new strip flatness control technology. As the control element, electromagnetic sticks have a great effect on the control ability of RPECT. To improve control ability and extend service life, effective control ratio of electromagnetic stick is presented in this paper. The ratio is designed based on the structure character of electromagnetic stick, and can be used to evaluate the key parameter of electromagnetic stick. Based on the coupled FEM, the heat flux density of the roll inner hole and the temperature distribution of electromagnetic stick are analyzed for different effective control ratios; the average contact pressure between electromagnetic stick and electromagnetic control roll is studied to evaluate the change of force roll profile; the state of roll profile and the stress state of the roll are researched to analyze the comprehensive control ability. Through the verification on the roll profile electromagnetic control experimental platform, the reasonable selection range of effective control ratio, which can be used to expand the roll profile axial affected area, is from 0.5 to 0.583. In order to increase the roll crown, the selection of ηd needs to consider the current density and the optimal selection range of effective control ratio.