Abstract: Liquid steel flow and heat transfer-solidification process were simulated and analyzed by CFX4 4 software ,and relation between relative process parameters and immersed nozzle structure has been discussed in order to decrease carbon segregation of 300 mm X 300 mm cast bloom of bearing steel. Production practice showed that a immersed nozzle with 4 holes was used instead of original one with straight hole, the center carbon segregation rating of cast bloom decreased from 1. 0 ~ 2. 0 to 1. 0 ~ 1. 5 , and the percentage of ≤1. 0 rating of bloom with using 4 holes nozzle was 79% while that with using straight hole nozzle was only 50% .

Key words: Bearing Steel, Cast Bloom, Immersed Nozzle with 4 Holes, Center Carbon Segregation

摘要： 为减少轴承钢300 mm×300 mm连铸坯的碳偏析,通过CFX-4.4软件仿真分析了连铸结晶器内钢水流动和传热凝固过程,探讨了有关工艺参数和浸入式水口结构的关系。实践表明,通过4孔水口替代直孔水口,铸坯的碳偏析级别由1.0～2.0级降至1.0～1.5级,采用4孔水口中心碳偏析≤1.0级占79%,直孔水口仅为50%。

关键词: 轴承钢, 连铸方坯, 4孔浸入式水口, 中心碳偏析