优碳钢板坯表面纵裂纹的形成与控制  

Formation and Control of the Longitudinal on the Surface of the Optimal Carbon Steel Slab

作　　者：李承虎 Li Chenghu(Fujian Sansteel Minguang Co.,Ltd.,Sanming 365000,Fujian)

机构地区：[1]福建三钢闽光股份有限公司炼钢厂,福建三明365000

出　　处：《福建冶金》2023年第5期31-33,30,共4页Fujian Metallurgy

摘　　要：福建三钢闽光股份有限公司炼钢厂板坯连铸生产的优碳钢铸坯因表面纵裂纹造成铸坯非计划落地修磨及轧材报废等情况时有发生,经过对连铸工序生产工艺的对比分析发现,导致铸坯表面纵裂纹主要与钢水的成分及温度、浇注过程的冷却强度、保护渣性能、拉速的稳定性及浸入式水口插入深度等因素有关。通过控制钢水中[S]含量小于0.015%、钢水到站温度控制在14℃~28℃范围内、稳定生产节奏控制250断面拉速在0.75~0.80m/min之间、优化浇注过程的冷却强度、跟踪保护渣使用效果等措施,优碳钢铸坯表面纵裂纹发生率得到明显改善,纵裂纹率由原来的0.23%降到现在的0.08%。For the optimal carbon steel slab produced by the slab continuouscasting,the situations such as the slab unscheduled ground grinding and rolling material scrapped,etc.caused by the longitudinal cracks of the surfaceoccasionally occur.Through the comparative analysis of the continuous production process,it is found that the longitudinal cracks on the slab surface are mainly related to the composition and temperature of the molten steel,the cooling strength of the casting process,the properties of the mold powder,thestability of the casting speed and the depth of the submerged nozzle.By controlling the content of[S]in molten steel is less than 0.015%and Steel station temperature control in the range of 14℃~28℃,Steady production rhythm control 250 section speed between 0.75~0.80m/min,optimizing the cooling strength of the casting process and tracking the effects of using mold powder,the incidence of longitudinal cracks on the slab surface is improved,The longitudinal crack rate from the original 0.23%to the current 0.08%.

关 键 词：板坯连铸 优碳钢 纵裂纹 冷却强度 保护渣 钢水质量 

分 类 号：TF777[冶金工程—钢铁冶金]