高品质管坯钢夹杂物控制技术研究

Research on inclusions controlling for the high quality tube billet

针对生产中存在的精炼渣氧化性控制偏高、钢水T.O含量控制及钙处理效果不稳定等问题,开展了高品质管坯钢非金属夹杂控制的技术研究。通过精炼渣系和生产工艺的优化,降低并稳定钢中T.O含量;通过热力学计算和实验室研究,确定了钙处理的工艺技术参数。工业试验表明:采用该研究成果后,钢中w(T.O)控制在15×10-6以下,钢中w(Cat)/w(Als)≥0.07,w(Ca)/w(S)≥1.9,改善了夹杂物的变性效果;高品质管坯钢轧材中A、B、C、D、Ds类非金属夹杂物均控制在1.0级及以下,A+B+C+D≤3.0级,满足钢种质量要求。

In the consideration of problems in producing process, such as high oxidation of refining slag, the fluctuation of T. O content in molten steel and calcium yield rate, the inclusion control technology had been researched in the high quality tube steel. The refining slag and producing technology had been researched, the T. O content was reduced and stable. The calcium treatment technology had been confirmed based on the thermodynamic calculation and laboratory research. Industrial tests showed that T. O mass fraction was not more than 15×10^-6,vo（Cat）/w（Als）was not less than 0.07, w（Ca）/w（S）was not less than 1.9 when the research countermeasures were applied. The modification of inclusion was improved. Every type of inclusions was not more than 1.0 level and A ＋ B ＋ C ＋ D was not more than 3.0 level. The inclusion control met the quality requirement of the steel.