The Influence of Different Factors on the Thermal Stress of Ladle Lining Under Typical Working Conditions

ABSTRACT The ladle is a critical piece of equipment for transporting high‐temperature molten steel in the steelmaking process, and its operational performance directly impacts the quality of the final product, energy efficiency, and overall production costs. With the advancement of continuous casting and external refining technologies, the stability of ladles under high‐temperature and high‐intensity service conditions faces increasingly stringent demands, particularly as the issue of thermal stress damage to the refractory lining becomes more pronounced. Based on typical steelmaking conditions, this study establishes a multi‐stage service cycle model for a 350‐ton ladle. Utilizing a parameterized finite element approach, we conduct a coupled transient thermo‐mechanical simulation to analyze the temperature and stress fields, specifically investigating the synergistic effects of thermal expansion, temperature gradient, and ferrostatic pressure. The results demonstrate that thermal stress is the predominant factor responsible for lining damage. Notably, the thermal expansion behavior of the refractory materials exerts a significant influence on the distribution and magnitude of thermal stress within the ladle structure. In contrast, mechanical loads such as the static pressure from the molten steel contribute minimally to the overall stress state. Furthermore, the study reveals that the stress on the ladle shell significantly reduces after the refractory lining fails and expansion pressure diminishes, quantitatively highlighting the critical role of interfacial expansion constraints. This research provides a comprehensive theoretical foundation and valuable engineering insights for the optimized design and longevity enhancement of ladle lining structures.