连铸小方坯综合凝固系数测定及优化实践

Composite solidification coefficient determination of continuous casting billet and process optimization

利用射钉法对河南济源钢铁(集团)有限公司一钢厂小方坯进行测试研究,从而测定二冷区的坯壳凝固厚度,并根据铸坯凝固定律计算了液相穴长度和综合凝固系数,为发挥铸机良好的冷却效果提供合理的拉速和比水量参考。研究了拉速、比水量、钢液过热度等因素对铸坯凝固可能产生的影响,并针对目前济源一钢厂2号连铸机的末端电磁搅拌位置进行重新评估,提出合理的安装位置和相关工艺参数的优化结果。通过实际验证,改进后的工艺下各钢种的碳偏析指数在1.11值以下,达到了企业对产品质量的控制要求。

Nail-shooting technique was applied in measurement of billet produced by Jiyuan Iron ＆ Steel Company, then the thickness of solidified slab shell in secondary cooling region was measured. The liquid core length and the solidification coefficient of continuous cast billet were calculated by use of the solidification law. Reasonable casting speed and the radio of water for cooling effect of the caster were provide, and effects of casting speed, the radio of water, superheat of liquid steel on the solidification of the continuous casting billet were taken further research. According to the current end position of the electromagnetic stirring condition on Jiyuan No. 2 Caster, the reasonable installation position and optimization results of the specific process parameters were put forward. The result showed that the steel carbon segregation index was below 1.11 after improvement, which met the enterprise control requirements of the product quality.