| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the generation of chattering due to insufficient lubrication by dissolving the insufficient lubrication at high-speed rolling in a method for cold-rolling using a circulation type rolling oil supply system. SOLUTION: The method is for cold-rolling a steel strip using a cold-rolling device which has circulation type 1st rolling oil supply means for supplying 1st emulsion toward rolls and roll bite and 2nd rolling oil supply means for supplying 2nd emulsion having an average particle diameter larger than the average particle diameter of the 1st emulsion toward the surface and back faces of the steel strip in a position a prescribed distance apart from the roll bite on the side of an upstream stand, and this method is provided with a 1st supplying stage for supplying the specified volume of the 1st emulsion from the time when rolling is started by the 1st rolling oil supply means and raising the rolling speed and a 2nd supply stage for detecting the variationΔυof the rolling speed in the 1st supply stage, finding the variationΔμof the coefficient of friction between the steel strip and the rolls and furthermore, starting the supply of the 2nd emulsion by the 2nd rolling oil supply means at the point of time when the ratioΔμ/ΔυtheΔμto theΔυis changed from the minus to the plus.</p> |
