Abstract: Based on the production data the analysis on thermodynamics, kinetics of RH carbon-oxygen reaction and natural decarburization in 120 t RH refining process of low carbon steel QD08 (/% ： W0. 07C, 0. 15 〜0. 35Si, 0. 25 〜 0. 45 Mn, W0. 035P, W0. 035 S) has been carried out to get the optimized process for RH refining natural decarburization. The results show that with BOF end temperature ≥l650 °C , RH initial temperature of liquid ≥1600 °C , BOF end [C] 0.04% ~0.10% , end [P] ≤ 0.018% , before BOF tapping adding top slag lime 200 kg and during tapping non-adding alloy and deoxidation agent, and RH vacuum 4 ~8 kPa for 6 ~ 8 min, the liquid [C] shall decrease to ≤ 0,05%.

摘要： 基于生产数据对120 t RH精炼低碳钢QD08(/%:≤0.07C,0.15～0.35Si,0.25～0.45Mn,≤0.035P,≤0.035S)进行了RH碳氧反应的热力学、动力学分析和自然脱碳分析,得出RH精炼自然脱碳的优化工艺。结果表明,BOF终点温度≥1650℃,RH初始温度≥1 600℃,BOF终点[C]0.04%～0.10%,[P]≤0.018%,出钢前加顶浇石灰200 kg,出钢不加合金和脱氧剂,RH真空度4～8 kPa,6～8 min可使钢水[C]≤0.05%。