Abstract：The clogging of secondary cooling nozzle for continuous casting would cause uneven distribution of cooling water, which leads to large temperature difference on the surface of billet, resulting in crack defects of billet and seriously reducing the yield of rolled products. In view of the frequent nozzle clogging for No.4 billet caster in Xianggang, types and sources of nozzle blockage were comprehensively and systematically analyzed, and the corresponding control measures were put forward. The analysis results show that the nozzle clogging materials are mainly divided into four types, dense iron oxide with prominent edges and corners, spherical iron oxide, amorphous oxide containing P, Si and Ca and iron oxide with porous and loose structure, which come from the scaling of carbon steel parts behind the sedimentation tank of water station and continuous casting backwash filter. When the carbon steel parts behind the backwash filter are replaced with stainless steel, the iron oxide with porous and loose structure in the nozzle blockage disappears, the nozzle blockage is significantly improved, and the maximum number of nozzle blockage is reduced from 5-8 to 0-2.
刘喜锚, 史伟宁. 连铸二冷系统喷嘴堵塞物来源分析和控制措施[J]. 中国冶金, 2022, 32(9): 73-78.
LIU Xi-mao, SHI Wei-ning. Source analysis and control measures of nozzle blockage in continuous casting secondary cooling system[J]. China Metallurgy, 2022, 32(9): 73-78.
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2022, Vol. 32 
