METHOD AND INSTRUMENT FOR MEASURING MEANDERING OF METAL PLATE AND MANUFACTURING METHOD FOR METAL PLATE USING THE MEASURING METHOD

摘要

PPROBLEM TO BE SOLVED: To provide a measuring method for meandering by which the amount of meandering of a metal plate is accurately and stably measured even under inferior environment by using an inexpensive and small two-dimensional imaging unit. PSOLUTION: The method is for measuring the amount of meandering of the metal plate S to perform the meandering control of the metal plate S rolled with a rolling mill which is provided with a plurality of rolling stands and the method is provided with a step wherein the surface of the metal plate S is imaged with two-dimensional imaging unit 11, 12 from directions which are inclined in the rolling direction to the perpendicular of the pass line, a step wherein the positions of the edges of the metal plate are detected for every scanning line by detecting a variation in the density value for every scanning line in the width direction about a picked-up image, a step wherein an approximate straight line is calculated by applying a method of least squares to the position of each edge detected for every scanning line, a step wherein the intersection point of the approximate straight line with a specified scanning line is calculated and a step wherein the amount of meandering is calculated on the basis of the position of the intersection point. PCOPYRIGHT: (C)2004,JPO