Numerical modeling of thermal evolution in hot metal coiling

Abstract

The use of coiling and uncoiling in the transfer table stage has important effects on the downstream temperature evolution throughout the hot bar in hot rolling, consequently, it has significant effects on both the uniformity of final mechanical properties and uniformity of final metallurgical properties. Consideration is given herein to the evolution of bar distribution of temperature in the transfer table, when coiling is present, in order to establish possible causes for the lack of the stated uniformity for eventual possible solutions. To address these issues, the mathematical equation of heat diffusion in a shape changing domain, is solved using a novel numerical strategy that uses both Finite Elements and Finite Differences. Numerical results are presented. Keywords Temperature evolution. Metal coiling. Finite elements. Finite differences. Modelado numérico de la evolución térmica en el bobinado de metales en caliente Resumen El uso de estrategias para el bobinado y enderezado en la etapa de la mesa de transporte tiene repercusiones importantes en la evolución de la temperatura, aguas abajo, en el planchón de metal caliente; en consecuencia, tiene efectos significativos sobre la uniformidad de las propiedades mecánicas y metalúrgicas finales una vez concluido el proceso. Este trabajo estudia la evolución de la distribución de temperatura en la etapa de la mesa de transporte, en procesos de bobinado, con el fin de establecer causas que puedan originar la ausencia de la citada uniformidad. Para el estudio se resuelve la ecuación de difusión del calor en un dominio que cambia con el tiempo en una novedosa estrategia numérica que integra Elementos Finitos y Diferencias Finitas. Se presentan resultados numéricos de la simulación. Palabras clave Evolución de temperatura. Bobinado de metales. Elementos finitos. Diferencias finitas.

Simulation of Thermal Phenomena in Reverse Strip-Rolling Process

“…Although, this process step has obtained its importance due to development of new steel grades and progressive development of light metal production leading to new rolling technological schedules. There are a few models for the coiling process in literature [14,15]. The modelling idea of the coiling consists in the successive winding of the concentric rings on the mandrel where it corresponds to the coiling of one layer strip due to rotation.…”

Temperature Validation of 3D Model for the Reversing Hot Rolling in Connection with a Coil Model

“…In this context, reversing hot rolling has become increasingly important for the production of special steel grades [1] and lightweight materials like aluminum and magnesium alloys [2]. Today numerical simulation concerning reversing hot rolling process is usually focused on a consideration of individual process steps, such as coil winding or roll gap models [3][4][5]. In general, the state of the material resulted from its history and interaction with simultaneously running processes during the reversing hot rolling like temperature distribution of a un-or coiled coil is neglected.…”