The Development of the Reheating Equipment in the Hot Strip Line

In Shibukawa Plant, Daido Steel, many grades of the hot strip are rolled, like tool steels, stainless steels, the materials for electronic industry, and so on. In recent years, demands of the higher grade strip material like superalloys, permalloys and welding materials are increasing. In these materials which are difficult to roll, the edges of rolled materials are prone to crack. This cracking is caused by the temperature drop between the roughing stand and the finishing train. Shibukawa Plant developed the reheating equipment in the hot strip line. The characteristic of this equipment is that the Ceramic Surface Burner (C.F.B) with high heat transfer efficiency is employed. By using this equipment, the temperature at the edges of materials goes up approximately 60°C compared with conventional rolling. As a result, the occurance of the edge cracking decreased and the relationship between the edge cracking and the edge temperture of the material was made clear. This paper presents the reheating equipment and the reheating effects.