| 摘要 |
PURPOSE:To assure the passing characteristic of a strip and to prevent the snaking and drawing of the strip adequately by disposing a hearth roll which permits changing of the temp. distributions in the roll and free changing of the rate of crown in a continuous annealing furnace. CONSTITUTION:A central cavity part 12 and both end cavity parts 13, 13a are formed in a circumferential direction within the barrel part 11 of a hearth roll body 10 which is internally hollow. The barrel part is expanded to provide an adequate rate of crown by putting fluid in these and controlling the respective fluid temps. To this end, fluid circulating circuits 14, 15, 15a communicating with the respective cavity parts and coolers 16, heaters 17 and bypasses 16a, 17a for these are provided to the respective circuits. The circulating fluid is passed through the coolers 16 or the heaters 17 according to need so that the temp. distributions in the rolls are changed. When the generation of the snaking in excess of the set value is detected with detectors for the rates of snaking in proper places in the furnace, the rate of crown is controlled with a roll crown controller 20 so that the desired rate is obtained. |
