METHOD AND DEVICE FOR CONTROLLING PLATE THICKNESS DIFFERENCE IN WIDTH DIRECTION EXTENDING OVER LONGITUDINAL DIRECTION OF THIN STEEL SHEET

摘要

PURPOSE:To roll in longitudinal direction the thin steel sheet having no unevenness in the width direction plate thickness distribution by surveying the variation in the plate thickness distribution in the width direction from the plate thickness on each plural sections provided in the width direction of a rolled stock and by adjusting the work roll shifting according to the result. CONSTITUTION:A thin steel sheet is rolled by providing a work roll shifting device on the rolling stand of the up stream side than the last step rolling stand of a tandem rolling mill and by reducing the plate thickness difference in width direction of the rolled stock 1 with the establishment of the alternate shifting position of the work roll pair 2, 2 having a convergent taper on one end of the roll drum. In the above method, both ends of the width center of the rolled stock 1 are halved in the width direction respectively and the variation based on the progress of the rolling of the plate thickness distribution in width direction is surveyed with respect to each four sections in total. The rolling of the thin steel sheet having no unevenness in the width direction plate thickness distribution extending over the longitudinal direction is performed by adding the adjustment to the set-up of said work roll shifting position according to this measurement results.