Abstract: The pipeline steel(%:0.039~0.042C,1.56~1.62Mn,0.01Ti,0.05Nb,0.03V) was melted by torpedo desulfurization,adding low sulphur scrap in LD,LD tapping with slag stopper and adding deoxidizer Si-Fe and Mn-Fe and controlling end [C] 0.026%～0.030%,RH degassing treatment and alloying added Mn-Fe,LF refining with high basicity slag and feeding Ca wire.Examination results showed that in cast billet of pipeline steel the sulphur content was (10~18)×10^-6,the T[O]=30×10^-6,the size of most inclusions ≤40 μm,and the main inclusion was calcium aluminate with few Al₂O₃ and individual MnS being available to increase the resistance on hydrogen-induced cracking (HIC).

Key words: LD-RH-LF, Pipeline Steel, Cleanliness, Inclusions

摘要： 通过鱼雷罐铁水喷粉脱硫处理,转炉加低硫废钢、出钢挡渣和加Si-Fe、Mn-Fe脱氧,控制终点[C]0.026%～0.030%,RH脱气处理和加Mn-Fe合金化,LF高碱度渣精炼和喂Ca线冶炼管线钢(%:0.039～0.042C、1.56～1.62Mn、0.01Ti、0.05Nb、0.03V)。检验结果表明,生产管线钢铸坯中的硫含量为(10～18)×10^-6,T[O]30×10^-6,铸坯中大部分夹杂物尺寸≤40μm,主要夹杂物为钙铝酸盐,Al₂O₃夹杂和单独存在的MnS夹杂很少,有利于提高管线钢抗HIC(氢致开裂)性能。

关键词: LD-RH-LF, 管线钢, 洁净度, 夹杂物