Mold level stabilization using a standing wave model in continuous casting

Abstract

In continuous steel casting plants, it is very important to stabilize the molten steel level in the mold for quality of the final products and productivity. Standing waves in the mold cause periodic molten steel level fluctuations, which can deteriorate the product quality and productivity. Nevertheless, there has not been any effective countermeasure for them, because they are different from other disturbances in the sense that they are not changes in the flow rate of the molten steel and hence should not be controlled by manipulating the mass flow. This paper proposes a standing wave model and a mold stabilization technique that can prevent harmful influence of standing waves. This technique can prevent interactions between the mold level control and the standing waves in the mold by removing standing wave components from the original mold level signal. On-line experimental results have shown good performance and this technique has been in practical use in a continuous steel casting process in JFE.