A new simulation characterization method to reveal the causes of cracking for cast iron cooling staves

Abstract

As one of the core components for maintaining the longevity of blast furnace, cast iron cooling staves are widely used due to their low cost and excellent castability, but the poor thermal shock resistance making them susceptible to thermal cracking and unstable temperature fluctuations. In the study, a plane located 120 mm from cold side was selected and the temperature field was obtained through numerical simulation, and the area percentage exceeding the average temperature 145°C was quantitatively calculated and defined as high-temperature region. The high-temperature region ratio offers an intuitive and quantitative benchmark for comparing stave performance under varying boundary conditions. The impact of cooling medium parameters, stave structural parameters, and hot-side gas temperature on the cooling capacity were analyzed. The results indicate that the ratio of the high-temperature region serves as a more valuable cooling capacity evaluation index than traditional hot-side temperature measurements, typically falling within a range of 30-60%. Furthermore, the ranking of key factors affecting stave cooling capacity is elucidated, with gas temperature emerging as the most significant, followed by inlet water temperature, cooling water velocity, the ratio of cooling water pipe spacing to stave edge width, cooling specific surface area, and finally, the number of cooling water pipes. These findings provide a vital theoretical foundation and practical guidance for the design and optimization of blast furnace staves, aiming to achieve efficient and stable stave operation through precise parameter regulation. Ultimately, this contributes to enhancing the safety and longevity of the blast furnace smelting process.