X70管线钢中碳磷硫氮的控制

来源期刊：钢铁2010年第5期

论文作者：许晓东 朱志远 王文军 郝宁 吕延春

文章页码：20 - 23

关键词：管线钢； 成分控制； 二次精炼

Key words：pipeline steel； composition control； secondary metallurgy

摘    要：中亚天然气X70管线钢对钢材的强度、低温冲击韧性和落锤撕裂试验的要求很高,因此冶炼的钢水必须同时具有很低的硫、磷、氮含量及比较低的碳含量。为此,首秦钢铁公司采用"铁水脱硫-顶底复吹转炉—LF炉—RH精炼—板坯连铸"流程,通过冶炼工艺的改进和完善,成功地开发了X70管线钢,钢中硫、磷、氮等元素的平均质量分数为:S 15×10^-6,P 70×10^-6,N 39.2×10^-6,同时钢中碳的质量分数也稳定在0.055%左右。并对X70管线钢冶炼过程中上述元素的控制进行了讨论。

Abstract: The pipeline steel grade X70 used for Mid-Asia gas transportation project has very stringent requirements on its strength,toughness at low temperature and drop weight tear test(DWTT) values.Therefore phosphorus,sulfur,nitrogen and hydrogen contents in steel should be controlled as low as possible.At the same time low carbon concentrations with narrow ranges is also desired.At Shouqin metal materials Co.,Ltd.,X70 pipeline steel grade was successfully produced with the "hot metal desulphurization-BOF-LF-RH-CC" routine.The carbon in steel is stabilized around 0.055%,and the average contents of sulfur,phosphor and nitrogen are 15×10^-6,70×10^-6 and 39.2×10^-6 respectively.The metallurgical technology for content control of above mentioned elements was discussed.