Non-linear partial least squares and its application to minimising scale formation at a steel hot mill

Scale is highly detrimental to surface quality for tinplate products. As there are a large number of process variables at a typical hot mill, non-linear partial least squares was used to study the influence of these process parameters on tertiary scale formation. It was found that a logit model containing just two partial least squares components provided an adequate best fit to the process data with the most significant variables being the average temperatures at which the steel strip was entering the finishing and rolling mills, the average crop shear temperature and the percentage of phosphorus present within the strip.