浸入式水口及其对板坯连铸结晶器流动行为的影响

Submerged entry nozzle and its effect on mold flow behavior of slab casting

板坯连铸是各种板带材生产的初级成形工序,铸坯质量与结晶器冶金效果密切相关,其中浸入式水口的作用至关重要。针对连铸生产技术现状与发展要求,在回顾板坯连铸浸入式水口发展历程的基础上,总结并讨论了至今对浸入式水口结构、工艺参数及其材质与结晶器冶金行为关系的认识。综合表明,浸入式水口直接影响着钢水注入结晶器后的流动、传热与凝固行为,进而影响结晶器冶金性能与连铸过程铸坯质量的控制效果,但至今尚缺乏定量的水口设计参数准则。鉴于实际生产中各类钢种可浇性、铸坯断面与拉速的差异性,从铸机生产组织和电磁控流角度出发,探讨了单一水口在多断面、多工况下实现理想浇铸的可能性。

Slab casting is the primary forming process for various steel plate and sheet production, in which the semi-product slab quality is closely related to the mold metallurgical function supported by submerged entry nozzles(SEN). In the light of the current situation of slab continuous casting and the need for further development, the understanding to the geometry design, practice parameters and material category of SENs has been summarized in the paper based on reference review. It is shown that the adoption of SENs plays an important role in mold metallurgical behavior and the resultant slab quality, but there is no clear quantitative criterion to date for the design and application of SENs during casting production. In view of the frequent variation in castability of steel grades, slab formats and the related casting speed during actual production, the service organization for casting machines and the fluid flow control for SEN outlets by an electromagnetic facility have been discussed, which is supposed to realize an identical ideal mold flow pattern with a given SEN for any changing casting situation.