Strip crown measuring method and control method for continuous rolling

Abstract

In the continuous rolling mills, the strip crown and the strip flatness of a strip can be controlled to any desired value. In the strip crown measuring method, the strip crown of the first stage rolling mill can be obtained by adding the set target strip crown value and a value obtained by multiplying the deviation in mechanical strip crown between the predicted value and the actually measured value by a imprinting ratio. Further, the strip crowns of the second and after rolling mills can be obtained by adding the set target strip crown, a value obtained by multiplying the deviation in mechanical strip crown between the predicted value and the actually measured value by a imprinting ratio, and a value obtained by multiplying the deviation in entry strip crown between the target value and the calculated measurement value by an inheritance coefficient, for each rolling mill. Further, in the control method of the continuous rolling mills, the rolling mill is controlled in correspondence to the deviation in strip crown between the value actually measured by the profile gauge and the previously calculated value, in such a way that the manipulated variables of the actuators of the rolling mills arranged on the upstream side of the rolling mill having the profile gauge are equal to each other or determined to a predetermined proportion by use of imprinting ratios and inheritance coefficients.