板坯凝固末端区间铸坯变形与辊缝值设定的研究

Research on the deformation of slab in solidification end zone and the setting of roll gap

为了改善连铸板坯中心偏析和中心疏松等内部质量,建立了板坯凝固传热模型,分析了不同拉速下凝固末端区间铸坯的凝固收缩变形规律,计算了凝固末端区间内铸坯的鼓肚变形规律,综合考虑凝固收缩变形和鼓肚变形,设定凝固末端区间内扇形段辊缝值,和仅考虑凝固收缩设定的辊缝值,生产的铸坯内部质量分析结果表明,在设定连铸机扇形段辊缝时,综合考虑铸坯凝固收缩变形和鼓肚变形,对凝固末端区间的扇形段设定更大的辊缝收缩量,可以显著减轻铸坯中心偏析,改善铸坯内部质量。

To improve the internal quality of slab,such as central segregation and central porosity,a heat transfer model was established.The law of solidification shrinkage deformation in the solidification end zone at different casting speeds during was analyzed,and the law of bulging deformation in solidification end zone was calculated.Considering both solidification shrinkage and bulging deformation and only considering solidification shrinkage,the roller gap values of segments in solidification end zone were set.The results of internal quality analysis showed,when setting the roll gap of the continuous casting machine sector section,that the roll gap shrinkage amount of segments in solidification end zone can be set more larger under considering both solidification shrinkage and bulging deformation,it can significantly reduce the center segregation and improve the slab internal quality.