小方坯连铸漏钢形成原因分析与控制  

Formation mechanism and control measures of breakout for billet continuous casting

作　　者：苏笃星 邹长东 周青峰 

机构地区：[1]江苏省(沙钢)钢铁研究院,江苏张家港215625

出　　处：《炼钢》2017年第6期51-56,共6页Steelmaking

摘　　要：针对某炼钢厂低碳钢小方坯漏钢问题,通过对漏钢坯壳特征位置形貌的观察,采用金相显微镜及扫描电镜对漏钢坯壳、结晶器铜管进行分析。分析认为,一方面由于结晶器铜管外表面异常发黑,内表面镀层脱落,导致传热效果较差,引起坯壳生长不均匀;另一方面,漏钢钢种凝固收缩大增加了内应力,诱发铸坯产生内裂纹。过薄的坯壳位置成为应力集中点,出结晶器后,在无法抵御外力作用时,便导致漏钢发生。通过调整连铸工艺参数,降低结晶器冷却水质中硫酸盐含量,低碳钢漏钢发生率得到了有效控制,漏钢率由1.01%降低至0.30%。In order to explore the cause of the formation on breakout of the billets for low carbon steel, the characteristics of the breakout shell and the mold tube was investigated by optical microscope and scanning electron microscope. The result shows that the outer surface of the mold was attached with an unknown substance, what was worse, the inner surface plating was detached and the solidification shrink rate of the steel is high. Therefore, the heat transfer effect of the mold was poor, and as a result, the thickness of the shell was uneven and the internal cracks might generate. At last, when the weakest point of the billet shell couldn＇t withstand the external force, then the breakout would happen. By adjusting the appropriate continuous casting process parameters, and reducing the sulphate content of the mold cooling water, the breakout ratio of the low carbon steel decreased from 1.01% to 0.30 %.

关 键 词：连铸 小方坯 漏钢 结晶器铜管 冷却水 

分 类 号：TF777.3[冶金工程—钢铁冶金]