马钢重型异形坯纵裂纹处理优化研究

Optimization of longitudinal crack in beam blank of Masteel

异形坯的横断面形状不规则,有些部位存在应力集中的问题,导致在连铸生产中易产生裂纹等缺陷。针对异形坯出现的纵裂纹的问题,研究了锰硫比、拉速、一冷水量及钢水过热度等因素对纵裂纹发生率的影响。结果表明,适宜的锰硫比、拉速、一冷水量和过热度可明显降低纵裂纹发生率。通过工艺优化,裂纹废品率有所下降,总裂纹废品率降到了7.8 kg/t。

The cross section of the shaped blank is irregular,and some parts are with stress concentration problems,which makes it easier to produce cracks and other defects in continuous casting.In order to address the problems of shaped blank longitudinal crack,affecting factors as the manganese sulfur ratio,drawing speed,cold water amount and liquid steel superheat have been studied.The results show that the proper Mn/S ratio,drawing speed,primary cooling water and superheat can significantly reduce the occurrence rate of longitudinal cracks.After process optimization,the total crack rejection rate is decreased to 7.8 kg/t.