摘要
采用120 t顶底复吹转炉-LF-VD-Φ150～Φ200 mm圆坯连铸流程,通过控制铁水有害残余元素含量,强化转炉前期脱磷,控制终点[C]≥0.10%,出钢钢包渣厚≤50 mm,控制精炼终渣(FeO+MnO)≤1.0%,提高VD过程底吹氩流量至200～300 L/min,连铸全程保护浇注等措施,天钢完成J55(37Mn5),L80(TC80,0.24%～0.28%c,1.40%～1.55Mn),N 80(36MrdV)和P 110(26CrM04)级石油套管钢连铸圆坯的开发生产。生产结果表明,J55钢级的全氧含量≤25×10^(-6),P≤0.020%;N80、LS0和P110级别的全氧含量≤20×10^(-6),P≤0.015%;残余有害元素(Pb+Sn+As+Sb+Bi)≤140×10^(-6),夹杂物总量≤2.5级,圆管坯的中心疏松和缩孔等分别≤1.0级。
With using 120 t top and bottom combined blown converter-LF refining-VD-Ф150-Ф200mm mm round billet casting flow sheet, the development and production for casting round billet of J55 （37MnS）, LS0 （TCS0, 0. 24% - 0. 28%C, 1.40%- 1.55Mn）, N80 （36Mn2V） and Pll0 （26CrMn4） grade oil case steel have been completed at Tian- steel by the measures including controlling residual deleterious elements content in metal; intensifying converter dephos- phorizing in early phase, controlling end [ C] ≥0. 10% and after tapping slag layer thickness in ladle ≤50 mm; controlling ingredient of refining slag and end slag （ FeO ＋ MnO） ≤ 1.0% ; increasing bottom argon flow rate to 200 - 300 L/rain in VD process; and shielding casting in whole casting process. Production results show that for J 55 grade steel the total oxy- gen content is ≤25 × 10^ -6 and P≤0. 020% ; for L80, N80 and P110 grade steels the total oxygen content ≤20 × 10^ -6 and P≤0. 015% ; the residual deleterious elements （ Pb ＋ Sn ＋ As ＋ Sb ＋ Bi） ≤ 140 × 10^ -6 ; the rating of total inclusions in steel ≤2. 5 and the ratings of central porosity and shrinkage cavity are respectively ≤1.0.
出处
《特殊钢》
北大核心
2013年第3期42-44,共3页
Special Steel
