| 摘要 |
PURPOSE:To manufacture a cold rolled steel strip free from scale defects by covering the upper surface of a slab with a steel plate and charging the covered slab into a heating furnace to prevent the formation of deep-rooted oxide scale biting into the surface grain boundaries. CONSTITUTION:The upper surface of a slab 2 is covered with an inexpensive ordinary steel plate 3, and the covered slab 2 is charged into a heating furnace 4 through a conveying table 1 and heated with burners 5. Thus, the local heating of the upper surface of the slab 2 can be prevented, and the formation of deep- rooted oxide scale biting into the grain bounderies can be prevented. By hot rolling and cold rolling the heated slab, a high quality cold rolled steel strip free from scale defects can be manufactured. |
