连铸板坯偏离角纵裂的质量控制

Quality Control over Slab Longitudinal Crack at Deflection Angle

根据天铁热轧1650mm板坯连铸生产实际,偏离角纵裂缺陷在包晶碳钢产生几率大于其他含碳范围钢。通过对连铸板坯产生偏离角纵裂的原因分析,集中采取一系列措施,改善钢水在结晶器和二冷区的冷却条件,减少了作用在凝固坯壳上的机械应力,使得偏离角部纵裂质量缺陷得到有效控制,发生几率明显减少。

According to production practice at Tiantie 1650mm Slab Caster,the possibility of longitudinal crack at deflection angle in carbon peritectic steel is greater than any other carbon steel.The paper analyses the reasons how slab longitudinal crack at defection angle forms.A series of measures including improving the cooling condition for liquid steel at mould and secondary cooling area,reducing the mechanical stress on so-lidified shell are taken.Therefore,the quality defect of longitu-dinal crack at deflection angle is effectively controlled and the crack formation 's probability is reduced.