A Mathematical Model for Gas-Wiping Phenomena in Hot-Dip Galvanizing Process

Abstract

In the gas Wiping for continuous hot-dip galvanizing, a model analysis representing the relationship between its zinc coating weight and operating factors was carried out. By using this model taking the characteristics of two-dimensional free jet into consideration, new knowledge such as the fact that zinc coating weight is not influenced by its nozzle-slit gap in a jet range of narrow distance from nozzle to strip, etc., were obtained. Also with this model verified in Mizushima CGL, it was confirmed that the calculated value of zinc coating weight was in good agreement with its measured values. Furthermore, with these knowledge applied to the improvement of its operation using a zinc coating weight control, an optimization of nozzle-sit gap, etc., good results were achieved.