Melhoria no padrão de escoamento do aço líquido no distribuidor do lingotamento contínuo 01 da APERAM Inox América do Sul

• Ano de defesa: 2014
• Autor(a) principal: Joao Geraldo Alves
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Materiais e de Minas; Engenharia Metalúrgica; Engenharia metalúrgica
• Link de acesso: http://hdl.handle.net/1843/BUOS-9MVJ49

In addition to distributing and feeding liquid steel into the moulds, the continuous casting tundish has a significant effect on the floatation of non-metallic inclusions. Flow modifiers, such as dam, weir and turbulence inhibitors, are alternatives that can be used to optimize the liquid steel flow in the tundish. Previous investigations have demonstrated the benefits of using these devices in terms of improving the liquid steel flow and removing of non-metallic inclusions. All these studies aim at increasing the effective residence time of liquid steel in the tundish, increasing the plug flow. This can enable the flotation of non-metallic inclusions and, consequently, increase the cleanliness of the slabs and coils. To analyze the liquid steel flow inside the tundish, Residence Time Distribution (RTD) curves are normally determined. Mathematical modeling has been used to characterize the liquid steel flow in the continuous casting tundish and to determine RTD curves, with or without fluid flow modifiers. The tundishes of Continuous Casting Machines 01 and 02 at APERAM have different geometries, and the coils derived from the slabs cast in Machine 01, have quality results approximately 4 times worse than the slabs cast in Machine 02. Considering these observations, the objective of the present work was to study the fluid flow in the tundish of Continuous Casting 01, by means of mathematical modelling using the commercial software ANSYS CFX 14.0, and to identify configuration of flow modifiers (dam and weir) to improve the floatation of non-metallic inclusions. The validation of the mathematical modeling was carried out comparing the results of micro purity of samples of hot-rolled coils cast with and without the use of flow modifiers, of SAE 1070 steel. The micro purity results showed that the use of dam and weir as proposed in the present work improved the floatation of non-metallic inclusions in the tundish of Continuous Casting 01, which enabled the production of steels with higher quality requirements.