Influence of spray water distribution on cooling effect of C38N2 bloom
DU Xiao-chen1, LIU Qing1, ZHANG Jiang-shan1, WANG Chao2, LI Ming3
1. State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing, Beijing 100083, China; 2. School of Advanced Engineers, University of Science and Technology Beijing, Beijing 100083, China; 3. Nanjing Iron and Steel Co.,Ltd., Nanjing 225267, Jiangsu, China
Abstract：Reasonable secondary cooling process system of continuous casting is the key to improve the quality of non-quenched and tempered steel bloom. Taking 320 mm × 480 mm C38N2 non-quenched and tempered steel in a steel plant as the research object, a heat transfer and solidification model based on transverse water distribution of bloom was established, to analyze the influence of spray water distribution in each section of secondary cooling zone on the surface temperature distribution of bloom. The results showed that under the current spray conditions, the spray water at bloom corner in the first and second sections of the second cooling zone was large, and the surface transverse temperature differences of inner arc and side arc at the exit of the first section in second cooling zone reached 340 ℃ and 327 ℃, respectively. Meanwhile, the spray water at the bloom surface center in the third and fourth sections of the secondary cooling zone was large, and the surface recovery temperatures of inner arc and side arc in the air cooling zone were 109 ℃/m and 125 ℃/m, respectively, which was easy to cause corner cracks and internal cracks. On this basis, a spray nozzle arrangement mode of "lowering spray height in the first and second sections + increasing spray height in the third and fourth sections of the secondary cooling zone " was proposed. After the optimization of spay water distribution, the transverse temperature difference at the exit surface of each section of the secondary cooling zone was basically controlled within 200 ℃, the surface recovery temperatures of inner arc and side arc in the air cooling zone were reduced to 95 ℃/m and 107 ℃/m, respectively, and the corner recovery temperature was reduced from 94 ℃/m to 40 ℃/m, which reduced the incidence of crack defects. The result of study can provide reference for continuous casting production of non-quenched and tempered steel.
杜肖臣, 刘青, 张江山, 王超, 李明. 喷淋水量分布对C38N2钢大方坯冷却效果的影响[J]. 中国冶金, 2022, 32(5): 93-101.
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2022, Vol. 32 
