| 摘要 |
PURPOSE:To easily form dimples having the necessary irregular distribution on the whole circumference of a cooling drum by forming a pattern irregularly distribution with the dimples over the whole circumference of the cooling drum and etching this. CONSTITUTION:The individual dimple formed on circumferential surface of the cooling drum is made 5-100mum depth and 0.1-1.2mm diameter under consideration of slow cooling effect, restraint to the solidified shell, workability, etc. Black points showing position where the dimples are formed on circumferential face of the cooling drum with etching are set at random to manufacture a dimple pattern manuscript note. From this manuscript note, a film 12 picturing the black points to the planning position for forming the dimples is manufactured. The film 12 is wound on the cooling drum 13 coated with masking resin 14 on the whole circumferential surface and the surface of the drum 13 is etched through irradiation of ultraviolet ray 15, chemical treatment, etc., to form the dimples corresponding to the black points. The cast strip having good quality without any defect of crossing fold, etc., is obtd. with this drum 13. |
