复吹转炉冶炼高级别管线钢低磷控制

Low phosphorus control in pipeline steel of combined blowing converter steelmaking

随着铁水磷含量的增高,邯钢邯宝炼钢厂250t复吹转炉在冶炼高级别管线钢时对钢中磷含量的控制越来越难。从转炉脱磷的热力学和动力学理论两方面进行了分析,并针对性地制定了转炉吹炼过程去磷的有效措施,包括采用转炉留渣操作提高前期去磷效果、提高炉渣碱度、对于铁水磷质量分数高于0.12%的炉次采用少渣冶炼、吹炼过程枪位比优化前提高200mm和应用出钢下渣检测和滑板挡渣技术降低回磷等。转炉冶炼工艺优化后,转炉终点磷的质量分数平均值由优化前的0.012 2%降低到优化后的0.008 9%,钢包磷质量分数由0.013 5%降低到0.009 6%,为邯宝炼钢厂大批量生产优质高级别管线钢等洁净钢打下了基础。

With the increase of phosphorus content in hot metal,it becomes more and more difficult to control the phosphorus content of pipeline steel in 250 tcombined blowing converter of the Hanbao steel-making plant.the thermodynamics and dynamics theory about dephosphorization of converter steelmaking process was analyzed,and the measures were introduced including remaining slag practice to raise the effect of dephosphorization,increasing the slag basicity,application of less slag when the phosphorus content of hot metal preponderate over 0.12%,control of lance movements of 200 mm higher than before,and the application of slag-stopping tapping by slide gate,etc.After application of these measures,the average w[P]at blowing end-point reduced from 0.012 2% to 0.008 9%,and the w[P]at ladle reduced from 0.013 5%to 0.009 6%.It has provided theoretical basis for Hanbao Steel to produce clean steels such as high-level pipeline steel.