转炉冶炼N80顶吹N_2后搅拌技术研究

Study on Stirring Technology for Smelting Molten Steel for N80 Oil Casing in Converter by Top-blowing N_2

通过对转炉冶炼N80顶吹N2进行后搅拌的工业试验研究,探讨了顶吹N2对熔池温度及成分的影响。结果认为,顶吹强度4.0-4.5 m^3/（t·min）的N2,喷吹时间≤1.5 min时,熔池平均增氮量仅为0.000 033%,平均增氮速率为0.000 01%/min;对碳含量有一定的影响,平均脱碳速率为0.005%/min;对磷含量影响明显,平均脱磷速率为0.002 2%/min;温降较大,平均温降速率为15.4℃/min;顶吹N2前后炉渣中铁的氧化物含量未出现明显的规律性变化。

Based on the industrial experimental study on top-blowing N2 into the converter for smelting molten steel for the NS0 oil casing by post stirring method, the effect of top-blowing N2 on the temperature of molten bath and compositions is discussed. It is concluded that the average content of increasing nitrogen in the molten bath is only 0.000 033% and the average rate of increasing nitrogen is 0.000 01%/rain when the intensity of top-blowing N2 is 4.0-4.5 m^3/（t· min）, which has certain influence on the content of carbon while the average decarbonizing rate is 0.005%/rain but has remarkable influence on the content of phosphorus while the average dephosphorizing rate is 0.002 2%/rain. On the other hand, the temperature drop is relatively large for the temperature in the bath by post stirring method, indicating that the average temperature drop rate is 15.4 ℃/min. However the content of iron oxide in the slag has no remarkable, obvious, regular change before or after top-blowing N2.