Filler Sand contribution to Non free Opening Mechanisms in Steelmaking Ladles

L. MARTORELLO ; A. GIMENEZ; A. LAMBERTINI; L. MUSANTE; P. GALLIANO

Rosario

Conferencia; 20º Steel Conference IAS 2014; 2014

Instituto Argentino de Siderurgia (IAS)

High free opening rates improve steel quality by reducing oxidation risk when the ladle is opened by an oxygen lance. Plant productivity and safety conditions are also affected due to the casting delay and required the additional operations that are required for the opening of the ladle. Many different operative variables affect the non-free opening mechanisms that avoid a prompt steel flow from the ladle to the tundish. Although it is known that ladle filler sands play an important role in most of these mechanisms, it is not must be clearly how do they affect the opening performance. Different types of sands areincorporated into the inner nozzle and well block, being chromite- and zircon-based sands the most widely used. Many variables are usually considered to affect the performance of these filler sands, such as chemical composition, granulometric distribution, particle shape, carbon content, moisture level, and materials refractoriness. In this work, an overview of the different commercial available ladle sands is described, including its lab characterization. A description of main non-free opening mechanism in operation is also shown. Focus is done in the evaluation of the effect of long steel treatments in the ladle sand performance through both in-plant data and numerical models.