CSP薄板坯表面纵裂的成因与控制

根据CSP薄板坯连铸过程中铸坯表面纵裂纹的形成机理,结合武汉钢铁股份有限公司CSP生产现场实践,从钢水成分、锥度设定、保护渣、冷却制度、设备精度等方面因素对板坯裂纹的产生、发展进行分析,为有效控制薄板坯表面纵裂提出了相应措施,攻关后,由纵裂引起的改判比率由2009年12月的3.22%降至2010年12月0.43%,板坯纵裂纹缺陷得到有效控制。

Reasons for formation of longitudinal crack of CSP slab and preventing measures

Longitudinal cracks on surface of thin slab are common defects in continuous casting of CSP.According to the formation mechanism of longitudinal cracks in continuous casting process of CSP slab,combining with site experience of WISCO production,this article analyses the reasons of formation and expansion of longitudinal cracks from composition of liquid steel,taper of mould,behavior of casting powder,second cooling condition,equipment accuracy and so on.The article puts forward the measures for effective control the longitudinal cracks of CSP slab.After tackling key measures,the modify ratio reduced from 3.22 % in December 2009 to 0.43 % in December 2010,and longitudinal cracks are effectively controlled.