BOF-LF-CC流程生产齿轮钢铸坯全氧含量控制实践

摘要

The 20CrMnTiH gear steel was produced by BOF-LF-CC process in Laiwu Steel. In the condition of without VD furnace vacuum processing, through adopting some process optimization measures such as increasing the hit-rate of carbon content in converter endpoint, using combined stopping slag technology, optimizing converter bottom blowing flow rate and the ladle bottom blowing argon mode, adopting full aluminum deoxidation, adjusting the refining slag system, improving the sealing of long nozzle for avoiding secondary oxidation of the molten steel and setting vibration slag detection system, the total oxygen content in the cast slab was decreased effectively. The average total oxygen content reached 0.001 3%.%莱钢采用BOF-LF-CC工艺流程生产20CrMnTiH齿轮钢，在不经过VD炉真空处理的情况下，通过提高转炉终点碳命中率，使用组合式挡渣工艺，优化转炉底吹流量及钢包底吹氩模式，转炉全铝一次脱氧，调整精炼渣系，提高大包长水口密封性，避免钢水吸氧二次氧化，引进钢包下渣自动监测系统等工艺优化改进措施，有效降低了铸坯全氧含量，平均铸坯全氧含量达到了0.0013%。