| 摘要 |
PURPOSE:To prevent the generation of scratch flaws, and to improve the quality of the rolled strip, by spraying a rolling mill oil of a prescribed concentration just before the steel strip is fed to work rolls. CONSTITUTION:At cold rolling a steel strip, a rollng mill oil as the coolant A is sprayed for cooling and lubricating rolling rolls; separatly from this coolant A, another high concentration coolant B containing a >=10% rolling mill oil is sprayed against the underside of the steel strip 3 between rolling stands before the steel strip 3 is bitten by work rolls while the cold rolling work is continued. The high concentration coolant B is sprayed at the timing and position just before the steel strip 3 is rolled, in order to make the collant B sprayed and stuck to the underside of the steel strip 3 very effectively work at rolling the strip 3. For example, in case of a five-stand tandem mill, scratch flaws readily generate at the 3rd and 4th stands wherein the rolling speed is high and the draft precentage is large, so that the coolant B is sprayed against the steel strip 3 before it is bitten by work rolls of these 3rd and 4th stands. |
