洁净石油管坯钢27CrMoNbV的生产实践

Production Practice of Clean Steel 27CrMoNbV for Petroleum Tube Blank

攀钢27CrMoNbV钢的流程为采用铁水预处理-120 t顶底复吹转炉-LF-RH-360 mm×450 mm坯连铸工艺,通过铁水预处理深脱硫,转炉双渣法冶炼脱磷,转炉出钢及LF精炼深脱硫、采用(1.6~2.2) CaO/Al_2O_3精炼渣系、RH处理喂Ca-Si线处理、保护浇注等工艺优化,生产的27CrMoNbV钢化学成分稳定,P≤0.010%,S≤0.004%,[H]≤1.5×10^(-6),T[O]≤0.001 1%,非金属夹杂A、B、C、D、Ds均≤1.0级,完全满足技术要求。

The flowsheet of steel 27CrMoNbV at Pansteel is hot metal pretreatment-120 t top bottom combined blown BOF-LF-RH-360 mm×450 mm bloom CC process.With the process optimization including hot metal deep desulfurization pretreatment,BOF double slag dephosphorization process,deep desulfurization in the process of BOF tapping and LF refining with(1.6~2.2)CaO/Al2O3 refining slag system,RH refining treatment by feeding Ca-Si wire and protective casting,the chemical composition stability of steel 27CrMoNbV is produced with P≤0.010%,S≤0.004%,[H]≤1.5×10-6,T[O]≤0.0011%.The rating of non-metallic inclusion of A,B,C,D and Ds are all≤1.0 rating,which fully meet technical requirements.