Panggang Group Research Institute Co., Ltd., State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization, Panzhihua 617000, Sichuan, China
In this paper thermodynamics analog calculation has been made for tube bloom in order to obtain a deoxidization technology and refining slag system. Industrial tests showed that if optical basicity and CaO /Al2O3 could be controlled at 0.75~0.80 and 2.0~2.5 respectively,then T[O]< 20 × 10-6 in molten steel.T[O] decreases with increasing [Als] for bloom,where [Als] exceeds 0.015% then T[O] < 20 × 10-6,and[Als]>0.020% then T[O]<15 ×10-6. The resulting technology can be effectively used to control the degree of purity. When T[O]≤2.0 × 10-6,total content of non-metallic inclusion averages 21.6 ×10-6 and all of the inclusion rating meet the requirements. For typical steel grades like B (PSL2) and JS25 Mn with stricter demand for [S]%,the average [S]have been controlled at 0.005% and 0.008% respectively.