Width fault diagnosis apparatus and method in hot strip mill

摘要

PURPOSE: A system and a method for diagnosing width fault in hot strip mill are provided to increase quality degree of rolled strip by predicting causes for abnormality in hot strip mill. CONSTITUTION: The system comprises a quality variable statistic operation part(214) for operating average vector of the selected quality variables and covariance matrix after selecting a plurality of rolled strip thickness quality variables; boundary value/examination value operating parts(215,216) for operating an upper limit boundary value of covariance matrix consisted of the quality variables and statistic examination value of coil to be diagnosed to check whether it is normal or not; a quality variable independent statistic examination value operating part(218) for operating statistic examination values of respective quality variables by judging which variables in the selected quality variables are causes for quality defects if the statistic examination values are the upper limit boundary value by comparing the calculated statistic examination values with an upper limit boundary value; a quality variable statistic examination value magnitude judging part(221) for operating an upper limit boundary value of the respective quality variables, sequentially verifying the respective quality variables to check which quality variables in the respective quality variables are causes for defects, and judging which is larger than the other in the statistic examination values of the respective variables and the operated upper limit boundary value of the respective quality variables; and a quality variable abnormality diagnosing result display part(222) for finally judging that the variables are causes for quality defects if the statistic examination values of the respective variables are larger than the operated upper limit boundary value of the respective quality variables as judgement results of the quality variable statistic examination value magnitude judging part.