Study On Optimization Of Flow Controlling Devices In Five-strand Billet Tundish

With the development of steel-making technology, it becomes more and more important to improve the cleanliness and quality of casting steel. The flowing condition of molten steel in tundish is considered very important to lengthen the residence time of molten steel in tundish, reduce the wrapped slag and improve the floating and excluding of inclusions included in molten steel. It has direct effect on quality of casting products. Therefore, it is very significant in theory and practical application to study and analyze the flow field and temperature field of molten steel in tundish and try best to make them proper.This paper studied a five-strand trapezium tundish in a specific steel plant. The flow control devices of trapezium tundish was optimized by the analysis and study of numerical and physical simulations methods. Using law of similarity as the academic base, According to geometric dimensions of the original tunidish, a 1:4 scale model was made in the laboratory. From the experiments, different flow parameters could be obtained in tundish with different configuration by measuring the liquid flow residence time distribution curves.Experimental result indicated that the structure of the present tundish was unreasonable, and the velocity of steel in the tundish was uneven, such as, the velocity of the impact area was very large, which produced turbulence, entrapment of slag and reoxidation of the molten steel, but the velocity of the steel in the two ends area was relatively small, which caused dead zone; the Residence Time Distribution Curve among strands of 3,4 and 5 was different, the characteristics of the fluid flow in the tundish was different, the response time, the average residence time, etc among the strands was different, the 3,4 strands had short the response time and the average residence time, small plug volume, large dead zone volume and existed short circuit flow.By using the schemeâ…£, the distribution of liquid steal and the characteristics of the fluid flow among the strands tended to reasonable, increasing the residence time and reducing the dead zone volume. When the casting speed at 2.2m/min, the characteristics in strands of 3,4 had improved, the response time of each had improved 4.5 and 2.3 times, the peak time improving 3.6 and 1.4 times, the plug volume increasing 6.4 and 3.4 times, the dead zone reducing 38% and 38.3%.