提高RH精炼铝镇静钢连浇炉数的研究及实践

Research and practice of increasing continuous casting heats for RH refining aluminum killed steel

针对钢厂生产实际情况,分析了RH精炼铝镇静钢存在的工艺缺陷。通过转炉炉后钢水的改渣处理,降低钢渣的氧化性、降低钢渣的熔点、改善钢渣的流动性、增大钢渣对夹杂物的吸附能力,以及降低加铝量、加强连铸保护浇铸等工艺措施,充分降低了钢水夹杂物含量,达到提高钢水质量的目的,最终获得了良好的钢水可浇性,浇次连浇炉数从优化前8炉增加到18炉,铸坯洁净度得到很大提高,改善了Al_2O_3夹杂物的评级,从而使得轧制缺陷率由优化前2016年全年2.24%降低到2017年全年的0.46%。

According to the actual situation of a steel mill, the process defect of A1 killed steel smelting by RH refining furnace was introduced. Though the slag modification treatment of the molten steel after the converter, the oxidation property of steel slag was reduced, the fluidity of steel slag was improved and the adsorption capacity of the steel slag to inclusion was increased. The slag modification, decreasing adding aluminum amount and reinforced protective casting were adopted to reduce the content of inclusion in the molten steel sufficiently, improving the quality of the casting billet and obtaining good protective casting. After optimization, the continuous casting heats increased from 8 heats to 18 heats in a casting times, the purity of that molten steel was greatly improved and the grade of Al2O3 inclusion formation was reduced, so that the annual defect rate of rolling was reduced from 2.24 % to 0.46 % in 2017.