Demonstration of a Continuous Billet Holding Furnace and Its Modelling

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Demonstration of A Continuous Billet Holding Furnace and Its Modelling Chang Rey-Cheia Huang l-Te and Jeng Jing-Lyang Energy & Resources Laboratories, Industrial Technology Research Institute Bldg.64, 195 Chung Hsing Rd., Section 4, Chutung, Hsinchu Taiwan 310 Fax: [phone] E-mail: [e-mail] Abstract A continuous holding furnace is designed and demonstrated to retrofit the temperature uniformity of square billets before entering billet mill. During operating at the temperature below 1150°C, the rollers speed in the holding furnace is periodically changed in a range of 10:1 ratio, whereas the pitch of rollers is designed as 600mm. The billets, with different cross section areas and length, were charged into the furnace to investigate the temperature distribution across the entire length. The results show as the billet is shorter than the furnace length, the computation modelling is able to accurately simulate the temperature distribution across the billet. In other words, for those billets longer than the furnace, the furnace has to exhibit reheating function in order to lift up the temperature of the billet portion exposed out of the furnace. A furnace demonstration is used to modify the assumptions m a d e in the modelling, and yet the investigations are continuously carried out. Introduction Rolling mill operation, an important step in steel-making process, has two major functions, the primary is the conversion of a steel casting (ingot) into rolled steel products; the secondary function is to produce these rolled steel products in pieces of the desired cross-sectional dimensions and weights (1 ) . Before charged into rolling mills, the temperature cross the entire ingot or billet is required to be uniform