MOLDING AND ROLLING METHOD FOR ROUGH H-SHAPED BILLET

摘要

PURPOSE:To efficiently roll a rough H-shaped billet having a desired flange thickness by subjecting a dogbone-shaped material to cross rolling down of flanges with intermediate caliber rolls for molding having two stages of tapered surfaces then rolling said material with the ensuing caliber rolls. CONSTITUTION:The dogbone-shaped material is first subjected to the cross rolling down of the flanges by the intermediate caliber rolls for molding having two stages of the tapered surfaces A, B having different taper angles on the flange surfaces of the calibers while the thickness at the front end of the flanges is controlled at the time of rolling the dogbone-shaped material with an open caliber roll. The bulging near the front ends of the flanges is thereby prevented and the overall flange thickness tF2 is increased. The material is successively subjected to the cross rolling reduction by the caliber rolls of which the caliber flange surfaces are straight taper surfaces. The thickness near the front ends of the flanges is thereby increased and the rough H-shaped billet having the flanges of the desired thickness is obtd.