HOT ROLLING METHOD AND HEAT TREATMENT FURNACE FOR STEEL MATERIAL

PURPOSE:To roll multiple kinds of steel materials efficiently by juxtaposing a walking beam type heat treatment furnace in the midway of a continuous casting device and a roughing device and charging ingots selectively therein for heat treatment. CONSTITUTION:A walking beam type heat treatment furnace 14 provided with a preheating zone 23, a heat holding zone 22 and a heating zone 24 or plural zones consisting of arbitrary combinations thereof is juxtaposed in the midway of a continuous casting device and a roughing device in rolling of steel materials. The furnace 14 receives the ingots discharged from the continuous casting device or the ingots cooled under various conditions and discharges the same arbitrarily. More specifically, in the case of a 3-zone system like the zone 22, the zone 23 and the zone 24, any of charging routes 34, 36, 37 may be employed, and the ingots can be fed from a discharging route 35 to the next stage. Thus the ingots are subjected to the best heat holding and heating in accordance with the changes in kinds, temp. and rolling conditions, and the furnace functions satisfactorily as buffers for post- and fore stages.