PDF《超低硫 X65QS 管线钢硫含量控制的 生产实践》

超低硫 X65QS 管线钢硫含量控制的 生产实践 李尚兵,张新文,薛伟江 (江苏永钢集团有限公司产品研发中心, 江苏 张家港 215628) 摘要:介绍了永钢采用

110 t 电炉→LF 精炼→VD 精炼→连铸工艺生产超低硫 X65QS 管线钢硫含量控制的生产实 践.

各工序硫含量得到严格控制,电炉平均脱硫率 16.35%. 出钢过程用铝

1 kg/ t 脱氧,同时随钢流加入石灰

6 kg/ t 和精炼合成渣

2 kg/ t. LF 炉采用喂铝线、复合碳化硅和铝豆对渣面扩散脱氧,造高碱度白渣对钢水深脱氧、脱硫,LF 炉平均脱硫率 89.2%,精炼结束后钢水平均硫含量 0.000 93%. LF 精炼结束到连铸工序过程平均增硫 0.000 1%,最终 成品硫含量平均 0.000 9%. 通过控制入炉料硫含量,提高 LF 精炼炉深脱硫能力,防止精炼后回硫等措施,生产的超 低硫 X65QS 大圆坯硫含量符合下游客户要求,具备批量生产成品硫含量在 0.002%以下的超低硫钢的能力. 关键词:超低硫钢;

管线钢;

精炼深脱硫;

脱氧 中图分类号:TF76,TF704.3 文献标志码:A 文章编号:1004-7638(2016)03-0115-04 DOI:10.7513/ j.issn.1004-7638.2016.03.022 Practice of Sulfur Content Control During the Smelting of Ultra-low Sulfur X65QS Pipeline Steel Li Shangbing,Zhang Xinwen,Xue Weijiang (Technology Research and Development Center,Jiangsu Yonggang Group Co.,Ltd., Zhangjiagang 215628, Jiangsu,China) Abstract:The production process of sulfur content control during the smelting of ultra-low sulfur X65QS pipeline steel in YongGang steel used

110 tons of electric furnace, LF refining , VD refining and continu? ous casting is present in this paper. The sulfur content at each individual process steep had been strictly controlled and average desulfurization rate is achieved at 16.35% for electric furnace. During tapping alu? minum addition is

1 kg / t molten steel for deoxidation, at the same time the lime and synthetic slag for re? fining are added at rate of

6 kg / t and

2 kg / t, respectively. Al wire is used in the LF furnace, composited SiC and Al shot are added for the slag surface diffusion deoxidization. And the resulting high basicitgy white slag are used for deep deoxidization and desulphurization. Desulphurization rate averages at 89.2% for LF furnace. The average sulfur content is 0.000 93% after LF refining. The average resulfurization is 0.000 1% through the end of LF refining to continuous casting steps. And the end sulfur content is 0?

000 9%. By controlling the sulfur content in the charge, improving deep desulfurization in the LF refi? ning furnace, and preventing the resulfurization after refining, the sulfur content of X65QS round bloom is far below specified 0.002% level. Key words:ultra-low sulfur steel, pipeline steel, refining deep desulfurization, deoxidization 收稿日期:2015-07-08 作者简介:李尚兵(1978-),男,宁夏平罗人,工程师,硕士,主要从事特殊钢冶炼工艺与产品质量控制及新产品开发等方 面的研究. Email:lishangbing2004@ 163.com. 第37 卷第

3 期2016 年6月钢铁钒钛IRON STEEL VANADIUM TITANIUM Vol.37,No.3 June

2016 0 引言 对于大多数钢种而言,硫对钢的性能会造成不 良影响. 在酸性气体环境中,导致管线钢失效的主 要质量问题是氢致开裂( Hydrogen Induced Crack? ing,简称HIC) 和硫化物应力腐蚀开裂(Sulfide Stress Corrosion Cracking,简称 SSCC),在大多数情 况下,HIC 都起源于夹杂物,而SSCC 的形成与 HIC 的形成密切相关[1~2] . 因此, 为了提高管线钢抗 HIC 和抗 SSCC 能力,炼钢过程必须深脱氧、脱硫, 减少钢中夹杂物、精确控制夹杂物形态[3] . 目前, 石油、核电等工业用钢要求 S 小于 0.003%,如高级 别海底管线钢等都要求钢中硫在 0.002%以下. 为 了满足特殊领域用钢对硫含量的要求,能稳定批量 生产超低硫钢具有重要的现实意义. 为此,永钢与 某钢管厂合作开发海底管线用超低硫 X65QS 无缝 钢管用钢,通过初炼、LF 精炼、VD 精炼、连铸各环节 严格控制,生产的超低硫 X65QS 大圆坯符合下游客 户制造无缝钢管的各项指标要求.