12th International Conference on Zinc & Zinc Alloy Coated Steel Sheet - GALVATECH 2021

During production of galvanized products, the Hot Dip Galvanizing bath is managed with additions of ingots allowing to guaranty the stability of the bath level and composition. Hot Dip Galvanizing pot productivity (in kg/h) is then defined as the amount of materials melted in the pot during a given time. The pot productivity is generally monitored to maintain the HDG bath at a stable level and vary depending on the production conditions (coating weight, line speed and strip width). In case of extreme process conditions (high coating weight, high line speed and wide strip), the pot productivity may become bottleneck, resulting on the necessity to limit the line speed to maintain the stability of the bath level, and thus affecting the HDG line productivity.

In the present paper, the different parameters affecting the pot productivity are highlighted and discussed considering the constraints induced by the ingots loading technology, but also by the ingots melting kinetic itself. Different ways to improve the pot productivity are then proposed and were investigated based on laboratory ingots melting trials, numerical simulations and on-line industrial trials with instrumented ingots.