Abstract: The flow sheet for bearing steel G55SiMoVA for oil drilling tool (/% ： 0.52-0.55C, 0.90-1.l0Si, 0.30-0.50Mn, 0.40-0.60Mo, 0.20-0.30V, ≤0.015P, ≤0.015S) is scrap+60%-70% hot metal-50 t UHP EBT EAF-60 t LF-VD-260 mm x 300 mm CC process. With using foaming slag submerged arc operation in whole period of arc furnace steelmaking, EBT tapping and alloying, controlling basicity 3.2-4.5 of LF secondary refining slag (/% : 46-54CaO, 10-16SiO₂, 11-13Al₂O₃ , 4.5-7.0MgO) , diffusion-deoxidizing by SiC with 60-80 L/min Argon stirring, VD for 20 min in vacuum below 67 Pa, and shielding casting in whole period, the oxygen content in bearing steel G55SiMoVA rolled products is 9 X 10^-6-10 x 10^-6

Key words: Bearing Steel G55SiMoVA, 50 t EAF-LF (VD)-CC Flow Sheet, Total Oxygen Content, Inclusion

摘要： 石油钻具用轴承钢G55SiMoVA(/%:0.52~0.55C,0.90~1.10Si,0.30~0.50Mn,0.40~0.60Mo,0.20~0.30V,≤0.015P,≤0.015S)的工艺流程为废钢+60%~70%铁水-50 t UHP EBT EAF-60 t LF-VD-260 mm×300 mm连铸。通过采用电弧炉全程泡沫渣埋弧操作,EBT出钢合金化,控制LF二次精炼渣(/%:46~54CaO,10~16SiO₂,11~13Al₂O₃,4.5~7.0MgO)碱度3.2~4.5,SiC扩散脱氧和60~80 L/min流量氩气搅拌,VD 67 Pa真空状态下保持20 min,连铸全程保护浇铸,所生产G55SiMoVA轴承钢轧材中氧含量为9×10^-6~10×10^-6。

关键词: G55SiMoVA轴承钢, 50 t EAF-LF(VD)-CC流程, 总氧含量, 夹杂物