美标结构钢A572Gr50折弯开裂原因分析及改善措施

Analysis and Improvement Measures for Bending Cracking of American Standard Structural Steel A572Gr50

针对CSP产线美标结构钢A572Gr50在加工使用过程中出现的折弯外侧开裂问题进行取样检测和分析,确定铸坯纵裂纹在轧制后形成的纵向表面裂纹是导致折弯开裂的主要原因。通过分析纵裂产生原因,采取优化保护渣成分、降低铸坯拉速等措施,减少铸坯冷却不均情况产生,从而抑制纵裂缺陷出现,避免折弯开裂再次发生。

The cracking on the outer side of the bending of the American standard structural steel A572Gr50 on the CSP production line during processing and use was detected and analyzed,and it was determined that the longitudinal surface cracks formed by the longitudinal cracks in the cast slab after rolling were the main cause of bending cracking.By analyzing the causes of longitudinal cracks,measures such as optimizing the composition of protective slag and reducing the casting speed are taken to reduce the occurrence of uneven cooling in the casting,thereby suppressing the occurrence of longitudinal cracks and avoiding the recurrence of bending cracks.