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Requirements like higher cleanliness and better quality of casting blooms are proposed for 350km/h higher speed rail steel. Present paper focuses on technical measures on improving the steel cleanliness and strand quality of 350km/h high-speed rail steel in Panzhihua Iron & Steel Group Company. By means of series of packaging technology like dephosphorization in BOF, ladle refining, mold electromagnetic stirring and dynamic soft reduction, dephosphorization rate cleanliness and morphology control are greatly improved, with [S] 0.015%, [P] 0.025%, [H] 1.5 Â 10 À6 , Al s 0.004%, T[O] 20 Â 10 À6 , the grade of central porosity and segregation 1.0, the grade of central crack and middle crack 0.5, index of central carbon segregation 1.05, severity level of type-A and type-B inclusions 2.0 and 1.0, respectively. The optimized process meets the technical requirements on producing 350 km/h high-speed rail steel and stable production is realized.