Magnetic Actuator Design for Strip Stabilizers in Hot-Dip Galvanizing Lines: Examining Rules and Basic Tradeoffs

Electromagnetic strip stabilizers are viable tools for controlling the shape of steel strips in hot-dip galvanizing lines. These stabilizers usually consist of multiple electromagnets located at the top and bottom sides of the strip. Although the general design of electromagnetic actuators is a well-established field of research, not all of this expertise is utilized in currently installed strip-stabilization systems. This article presents common design tradeoffs and rules for the construction and installation of these electromagnets and aims to assist the development of future strip stabilization systems. The behavior of thin steel strips in the magnetic field of the actuators is studied in detail. These results are extended to the multiactuator setup commonly used in hot-dip galvanizing lines. The negative effects arising from the magnetic coupling between the actuators are discussed, and the means used to prevent these negative effects are presented. Finally, all of the conclusions are validated via force measurements carried out in an industrial hot-dip galvanizing line.