Abstract:In the practical slab continuous casting, the uniformity of slab heat transfer in the secondary cooling has an important effect on the surface and internal quality of slab. Firstly, the spray parameters of the nozzles in different cooling zones a steel plant was tested, and a 3D heat transfer finite element model of a slab with 2 000 mm×250 mm section was established according to the layout of the nozzles and the corresponding water amount in each cooling zone for casting bridge steel, simulating and analyzing the dynamic heat transfer behavior of the slab in the secondary cooling zones. Base on these, optimized and adjusted the nozzle layout in the secondary cooling high temperature zones. The results show that the transverse surface temperature of the slab in the high temperature zone fluctuates greatly under the conditions of nozzle layout in the original secondary cold zone of a steel plant. Typical production process, the highest temperature of 1 073 ℃ of slab surface forms at the position of 313 mm away from the corner, the lowest temperature of 996 ℃ forms at 873 mm away from the corner in the exit of No.4 cooling zone, the difference value of the temperature reaches 77 ℃. When the slab enters the arc cooling zones, the transverse surface temperature distribution tends to be uniform gradually. Increasing the installation height of the nozzles of No.2 cooling zone from 170 to 200 mm and the height of the nozzles of No.3 and No.4 cooling zone from 200 to 240 mm from the slab surface, the maximum temperature difference of the slab surface in the high temperature zone would reduce to below 30 ℃. The uniformity of slab surface temperature may greatly improve.
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