| 摘要 |
PURPOSE:To improve thermal efficiency of a heating furnace and to decrease the axial thermal stress on the surface of a roll for conveying a steel ingot of high temp. in the heating furnace by providing small-diameter parts at plural points in the axial direction of the roll and covering the small-diameter parts with ceramic fibers. CONSTITUTION:A cooling-water feed pipe 4 is inserted into the internal hollow part of a roll 1 for conveying a steel ingot to be used in a heating furnace for heat-treating the steel ingot. Cooling water is introduced into the pipe 4 through the opening 5 thereof and is discharged through the other opening 6 into the hollow part to cool the roll from the inside while flowing toward the left in water flow spaces 8 formed of spiral vanes 7. The cooling water returns to the opening 5 and is discharged therefrom. The roll 1 is provided alternately with large-diameter parts 1a and small-diameter parts 1b. The parts 1b is coated with ceramic fibers 10. The load of the steel ingot is born by the parts 1a and the axial thermal stress of the roll by the effect of the high temp. is absorbed by the parts 1b. The deprival of the heat of the heating furnace by the cooling water or the roll and consequent decrease in the thermal efficiency are prevented by the fibers 10. |
