100t转炉-LF(VD)工艺冶炼轴承钢的氧含量控制

通过铁水预脱硫-100 t顶底复吹转炉-吹Ar-LF(VD)-方坯连铸工艺生产轴承钢的实践,得出冶炼终点钢水碳含量为0.2%~0.6%时,钢水氧含量在50×10^-6到150×10^-6之间;经出钢时脱氧、吹氩、LF(VD)精炼后,中间包钢水中的全氧含量为(14~16)×10^-6,铸坯中的全氧量<12×10^-6。分析表明,加强熔池搅拌,使钢渣充分反应,控制转炉下渣量<5 kg/t钢,加强吹氩搅拌,控制LF顶渣碱度在2.0~2.5之间,(FeO)+(MnO)小于0.5%,可使轴承钢中全氧量进一步降低。

Control of Oxygen Content in Bearing Steel GCr15 Steelmaking by 100 t Converter-LF(VD) Process

Through practice of bearing steel producing by hot metal pre-desulfurization - 100 t top and bottom combined blown converter - Ar stirring - LF(VD) - billet concasting process, it was obtained that with melting end point carbon between 0.2% and 0.6% , the oxygen content in steel was between 50 X 10^-6 and 150 X 10^-6 , by deoxidation in tapping, Ar stirring and LF(VD) refining, the total oxygen content in molten steel in tundish was between 14 x 10^-6 and 16 x 10^-6 and was less than 12 X 10^-6 in cast billet. The analysis results show that it is available to further decrease the total oxygen content in bearing steel by intensifying bath stirring to make steel-slag enough react, and controlling BOF tapping slag amount less than 5 kg/t steel, intensifying Ar stirring, and controlling LF top slag basicity between 2.0 and 2.5 and (FeO) + (MnO) less than 0.5% .