Junichi Tateno

Influence of Dog-Bone Width on End Profile in Plan View Pattern Control Method in Plate Rolling

A plan view pattern control method for plate rolling called the Mizushima Automatic Plan View Pattern Control System (MAS) or Dog Bone Rolling (DBR) was developed. In this method, the slab is given a non-uniform thickness pro le in the width direction to obtain non-uniform elongation at following at rolling. In order to make the plate more rectangular under various rolling conditions, prediction of elongation at following at rolling is necessary. In this research, the in uence of the width of the dog-bone (overly thick part at the slab width edge) on the sh-tail length (over-elongation at the slab end) is investigated. The sh-tail length increases as the dog-bone width increases and the dog-bone width ratio decreases. These phenomena are related to the following behavior of the restriction of excessive elongation in the dog-bone because of existence of unrolled volume before roll gap entrance: As the dog-bone width increases and the dog-bone width ratio decreases, the working length of restricting stress increases. Hence, restricting stress is released earlier and the rolling length for sh-tail formation increases. As a result, the sh-tail length increases. Therefore, in prediction of the plan view pattern, not only the dog-bone thickness, but also the dog-bone width and dog-bone width ratio should be considered. [doi:10.2320/matertrans.P-M2017805]