摘要
中间包浇注是连铸过程的重要工序,可分为稳态浇注和非稳态浇注两个阶段,其中非稳态浇注过程时间虽短,但该过程造成的钢液污染往往最为严重。为了减少非稳态浇注过程中的钢液污染,建立了中间包水模型试验系统,开展了“钢液-保护渣”两相水模型试验,研究了长水口插入深度、充包流量对中间包内的流动形态、混合特性以及渣金界面演变规律。结果表明,在稳态浇注过程中,发现长水口流量的增大将导致钢液的滞留时间增加,平均停留时间和死区体积分数减小;长水口插入深度的增加会将钢液的平均停留时间由原来的226 s延长至246 s。在非稳态浇注过程中,发现充包过程会出现渣层裸露现象即渣眼,且充包结束后再稳态阶段渣眼不会立刻消失。充包流量和长水口插入深度的增大均会导致渣眼面积增大,以及再稳态阶段渣眼存在的时间增加。当充包流量由2.18 m^(3)/h增至3.30 m^(3)/h时,最大渣眼面积由1871 mm^(2)增至19001 mm^(2),而再稳态渣眼存在时间也由41 s延长至232 s。
As an important operation procedure in continuous casting process,tundish casting can be divided into two stages:steady casting and unsteady casting.Although the unsteady casting process is short,the pollution caused by the process is often the most serious.In order to reduce the pollution of molten steel during the unsteady and steady casting process and improve the quality of liquid steel,the parameters in tundish were optimized better,and a second-flow tundish water model with geometric similarity ratio of 1∶4 was established.The tracer experiment,residence time distribution(RTD)experiment and three-phase cold water model experiment were carried out respectively.The effects of insertion depth and filling flow rate on the flow pattern,mixing characteristics and the evolution of slag-steel interface were analyzed.Experimental results from steady casting tests demonstrate that both the average residence time and dead zone volume fraction decrease with increasing flow rate at the long nozzle.Additionally,increasing the insertion depth of the long nozzle extends the average residence time of liquid steel from 226 to 246 s.In the unsteady casting test,it is found that the slag layer will appear in the filling process,that is,the slag eye will appear around the long water outlet,and the slag eye will not disappear immediately after the filling of the stable stage.The increase of the filling flow rate and the insertion depth of the long water outlet will lead to the increase of the area of the slag eye and the increase of the appearance time of the slag eye in the re-stability stage.When the insertion depth of the long water outlet is 90 mm,the charging flow rate increased from 2.18 to 3.30 m^(3)/h,the maximum slag hole area increased from 1871 to 19001 mm^(2),and the existence time of the re-stable slag hole also increased from 41 to 232 s.Considering the overall performance during the pouring stage,a long nozzle insertion depth of 90 mm demonstrates optimal performance.
作者
李希禄
刘鹏
杨军
姚毓超
刘中秋
LI Xilu;LIU Peng;YANG Jun;YAO Yuchao;LIU Zhongqiu(School of Mechanical and Power Engineering,Shenyang University of Chemical Technology,Shenyang 110142,Liaoning,China;Baoshan Iron&Steel Co.,Ltd.,Shanghai 201900,China;School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China)
出处
《连铸》
北大核心
2025年第3期37-45,共9页
Continuous Casting
基金
辽宁省教育厅面上基金资助项目(LJKMZ20220775)。
关键词
中间包
非稳态浇注
换包过程
长水口插入深度
水模型试验
tundish
unsteady casting
ladle changing process
long nozzle insertion depth
water model experience
