A continuous annealing line is the process which consists of heating, soaking and cooling of steel strips. In this process, it is very significant to control steel strip temperature and tension. If the steel strip temperature or tension is not controlled properly, it may cause unstable operations and, in the worst case, result in the trouble such as buckling of the steel strip. Once buckling occurs, it takes very long time to recover the process line and the productivity decreases. Therefore it is necessary to prevent these troubles by detecting signs of buckling as early as possible. While many trials to clarify the mechanism of buckling based on physical approaches were conducted in the past, it cannot find any appropriate technique with sufficient accuracy. For the above reason, data oriented approaches such as statistic analysis are studied as an alternative to the conventional monitoring method. In this paper, a new monitoring method for detecting buckling in continuous annealing lines is proposed based on canonical correlation analysis. It can extract not only relations among variables such as the strip temperature and tension but also the ones in the longitudinal direction of the strip and monitor changes of these relations. The off-line numerical tests are conducted and effectiveness of the proposed method is confirmed compared to the conventional method.
2015 The Society of Instrument and Control Engineers