Abstract：The ladle bottom blowing in the RH(Ruhrstahl Heraeus) vacuum refining process has received extensive attention in recent years as a way to improve the refining effect. In order to study the influence of ladle bottom blowing on actual production. The effect of ladle bottom blowing on dehydrogenation and inclusions in the RH vacuum refining process was studied through industrial production experiments. The results show that increasing the bottom blowing of the ladle optimizes the flow and mixing of the molten steel inside the ladle, increases the collisional growth rate of inclusions and the average size of the inclusions, improves the dehydrogenation effect, and increases the dehydrogenation rate, especially the dehydrogenation rate at higher hydrogen mass percent. When the bottom blowing flow is 30 and 50 L/min , the vacuum time required to remove hydrogen to 0.000 2% is reduced by 5.58% and 16.40%, and the dehydrogenation rate is increased by 9.76% and 19.51% at this time. In addition, the increase in the number density of inclusions decreased from 64.2% to 49.7% and 13.0%, and the increase in the average area of inclusions increased from 17.34% to 40.98% and 53.37%.
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2021, Vol. 56 
