方坯连铸高效化二冷技术

The Secondary Water Cooling Technology of High-efficiency Billet Continuous Casting

建立了方坯高效连铸二冷数学模型,提出了喷嘴有效喷淋系数和二冷有效比水量的概念.依据二冷均匀冷却的思想,重新设计并优化了二冷喷淋结构和喷嘴的布置,增加了一个二冷喷淋段.提出了新的二冷水模型,即Qi=a+bv+cv2=d(△T-30)+F;二冷各段的喷水量与拉速、浇铸温度、钢水成分和二冷水温相关.实践证明,经优化后的二冷结构和二冷水模型合理,拉速大幅度提高,150×150mm2断面的最高拉速达3.8～4.0m/min;铸坯质量明显改善,产量显著提高,经济效益显著.

The mathematical model of high-efficiency continuous casting of billet is developed in this paper.The concepts are put forward for the effective spraying water coefficient and the effective specific special water flowrate of secondary cooling.According to the idea of uniform cooling in secondary cooling zone,the spraying cooling structure and the disposal of nozzles are redesigned and optimized,and one spraying cooling zone is increased.A new secondary cooling model of spraying water is developed,which is a new formula Qi=a+bv+cv2=d(△T-30)+F.The research points out that the spraying water flowrate of each cooling zone is related to the casting speed,the casting temperature,the composition of liquid steel and the cooling water temperature of secondary cooling.The commercial run of the caster has proved that the spraying cooling structure and the new secondary cooling model are suitable,and the casting speed is enhanced in a great extent.The highest casting speed is up to 3.8～4.0 m/min for the billet of section 150×150 mm2.The billet quality is markedly improved,and the output is markedly increased.The economical benefit is greatly heightened.