| 摘要 |
PURPOSE:To excel in wear resistance and toughness, regardless of the roll size, by austenitizing the outer shell surface layer at a specified temperature and the inner shell at a lowest possible temperature, after as-casting. CONSTITUTION:In production of a compound roll having the outer shell made of high all by cast iron containing 3.0-5.0% Ni and 0.2-0.8% Mo, and the inner shell made of tough cast iron, a cast compound roll 3 is preliminarily borne on rotating rollers 4, 4, and the flames of a burner 6 installed in the interior of ring-shaped heating elements 5, 5' are injected to the surface of the drum part to heat it. The outer surface layer should be 850 deg.C or more, and the inner shell about 600 deg.C. Thus, after austenitizing the base, the heating elements 5, 5' are continuously moved, and cooling water is injected from a cooling body 7 to perform quenching and isothermal heat treatment at 200-450 deg.C continuously. |
