Polygonal Wear of Work Rolls in a Hot Leveler of Steel Making Machine (3rd Report, A Countermeasure by Using Dynamic Absorbers)

This paper deals with a countermeasure by using dynamic absorbers for polygonal wear of work rolls in a hot leveler. First, the authors discuss the optimal design of dynamic absorber mounted on a single degree-of-freedom system where the polygonal wear phenomena are generated. We obtain the characteristic root approximately, and apply the optimal design procedure of dynamic absorber for forced vibration of a single degree-of-freedom system to this self-excited vibration system. As the result, we obtain a design in which the system is stabilized perfectly. Secondly, the result is applied to a hot leveler as a two degree-of-freedom system through the modal analysis. As the result of numerical analysis, the hot leveler is changed into a perfectly stable system by two dynamic absorbers for the first and second vibration modes, and the polygonal wear phenomena are not generated at all.