Abstract: The cause and preventing measures for nozzle clogging during steelmaking process of ultra-low-carbon aluminium-killed steel such as XGM6 steel (/%: 0. 012C, ≤0. 012Si, ≤0. 08Mn, ≤0. 015P, ≤0.010S) produced by hot metal pre-desulphurization process-80 t top and bottom combined blown converter-LF-RH-280 mm x325 mm bloom concasting flow sheet have been studied. With using the process measures including controlling converter end [ O] ≤600 x 10^-6, LF top slag- high alumina slag + carbide, deoxidizing by adding aluminium shot after RH-OB decarburisation, controlling RH end [O] 20 x 10^-6 ~30 x 10^-6, RH end [Al]_s ≤ 0. 009%, tundish liquid superheating extent 25 ~40 °C and [Al]_s≤0. 004%, the nozzle clogging of liquid of ultra-low-carbon aluminium-killed steel has basically been avoided, continuous- continuous casting heats increase from less than 2 heats to more than 8 heats.

摘要： 研究了铁水脱硫预处理-80 t顶底复吹转炉-LF-RH-280 mm×325 mm方坯连铸流程生产XGM6钢(/%:0.012C, ≤0.012Si, ≤0.08Mn,  ≤0.015P, ≤0.010S)等超低碳铝镇静钢时水口堵塞的原因和防止措施。通过控制转炉终点[O]≤600×10^-6, LF顶渣为高铝渣+电石,RH-OB脱碳后加铝粒脱氧,控制RH终点氧含量20×10^-6~30×10^-6, RH终点[Al]_s≤0.009%,中间包钢水过热度25~40℃,[Al]_s≤0.004%等工艺措施,基本避免超低碳铝镇静钢水口堵塞,连浇炉数由不足2炉提高到8炉以上。

关键词: 超低碳铝镇静钢, 水口堵塞, 防止措施, [O] , [Al]s