炼钢 ›› 2015, Vol. 31 ›› Issue (2): 9-12.

• 生产实践 • 上一篇    下一篇

提高20Mn2钢洁净度的关键技术

郭宝奇1,包燕平2,林路3,王敏4   

  1. (北京科技大学 钢铁冶金新技术国家重点实验室,北京 100083)
  • 收稿日期:2014-07-31 修回日期:2014-09-23 接受日期:1900-01-01 出版日期:2015-04-05 发布日期:2015-04-23
  • 通讯作者: 包燕平 E-mail:baoyp@ustb.edu.cn

Critical technology of improving cleanliness of 20Mn2 steel

  • Received:2014-07-31 Revised:2014-09-23 Accepted:1900-01-01 Online:2015-04-05 Published:2015-04-23

摘要: 通过对20Mn2钢原有工艺的取样与现场数据分析,得出提高20Mn2钢洁净度的关键环节,包括转炉终点控制、精炼造渣、钙处理3方面。结合热力学的理论分析,得出3个环节的优化方案,分别包括转炉炉后控制过氧化现象,提高转炉终点w(C)≥0.08 %,并且控制终点w(P)≤0.015 %;炉后加入铝矾土与调节石灰加入量对精炼渣进行改质,使渣系成分落在w(CaO)=50 %~60 %,w(Al2O3)=20 %~40 %,w(SiO2)=5 %~10 %,w(MgO)=5 %;控制钙处理环节二次氧化,并将钙线的喂入长度控制在145~216 m。对优化工艺进行工业试验得出,连浇炉数由5.9炉升高至14炉,钢中氧含量明显下降,夹杂物数量与尺寸减小。

关键词: 20Mn2钢, 洁净度, 转炉终点, 精炼过程

Abstract: Through analyses of samples and plant data, critical steps of improving cleanliness of 20Mn2 steel were obtained, and it included control of endpoint of converter, refining process and calcium treatment. Based on integrating thermodynamics and theoretical analyses with practical process, optimized scheme including control of peroxidation at endpoint of converter by governing w(C)≥0.08%, w(P)≤0.015%, modification of refining slag by adding bauxite and adjusting amount of CaO to limit composition of slag in the range of w(CaO)=50 %-60 %, w(Al2O3)=20%-40%,w(SiO2)=5%-10%,w(MgO)=5%, and domination of reoxidation and length of CaSi wire within 145-216 m was obtained. Industrial trials of optimized scheme showed that continuous casting heats increased from 5.9 heats to 14 heats,oxygen content in steel declined dramatically, amount and dimensions of inclusions diminished.

Key words: 20Mn2 steel, cleanliness, endpoint of converter, refining process