动态轻压下模型的开发及优化

Development and optimization of the dynamic soft reduction model

为确保提高连铸板坯铸坯内部质量,开发了一套完整的轻压下模型,包括凝固传热、二冷水动态控制和辊缝控制模型,并对动态轻压下技术的关键参数进行了优化.通过射钉实验和铸坯表面温度测量,对该模型进行了校核.实验结果与模型计算结果较为一致;当拉速变化时,铸坯表面温度可以保证在较小的范围内波动.采用不同的轻压下参数进行生产试验,并通过铸坯低倍检验和中心偏析分析,对压下量和压下位置进行了优化,得出固相率(fs)0.2～0.5、单位压下量1.2mm.m-1为本铸机最佳的轻压下参数.

In order to improve the inner quality of slabs, a set of dynamic soft reduction models were developed, which include heat transfer, secondary cooling and roll gap control models, and the key parameters of soft reduction were optimized. The models were validated by shooting-pin tests and measuring the surface temperature of slabs. The measurement results agree with those calculated with the models, and the surface temperature fluctuation of slabs can be controlled in a narrower range when the casting speed changes. Production testing at different parameters of soft reduction was applied to optimize the percent reduction and reduction position by macrostructural examination and analyzing the center segregation. The best soft reduction parameters of this casting machine are that the solid ratio is 0.2 to 0.5 and the percent reduction is 1.2 mm· m^-1 .