宽度对板坯连铸结晶器液面特征影响

Effect of mold width on level characteristics in continuous casting mold of slab

由于订单日趋多样化,连铸过程中板坯宽度需要经常变化,同时由于浇铸周期的限制,通钢量一般维持不变。因此,固定通钢量研究铸坯宽度对流场的影响并采取相应控制策略有较大现实意义。采用1∶1水模型和工业试验研究了固定通钢量前提下宽度对板坯连铸结晶器内钢水液面特征的影响。水模型结果显示:宽度从1 050增至1 900 mm时,窄面撞击点位置由距弯月面370增至510 mm,且上回流涡心高度下移。通钢量固定为3.6 t/min,宽度从1 050增至1 900 mm时,液面平均波高从4.4降至2.5 mm,表面流速从0.42降至0.15 m/s。工业试验结果表明,通钢量为3.6 t/min时,结晶器内液面波动与表面流速随铸坯宽度增大而减小,与水模型结果一致。因此,在实际浇铸过程中,结晶器液面控制应根据铸坯宽度动态调节。

In continuous casting, the mold width inevitably varied to meet the requirements of the different customers. However, the casting throughput was not easy to change due to the constraint of casting period. Therefore, it is meaning- ful to investigate the effect of mold with on level characteristics at the fixed casting rates and control the mold level ac- cording to the results. A full scale water modeling and industrial experiments was carried out to investigate the effects of mold widths on meniscus characteristics in the mold of slab at the fixed steel throughputs. The results of water modelling show that the location of jet impingement point on narrow faces decreases from 370 mm to 510 mm as the mold width in- creases from 1 050 mm to 1 900 mm. Furthermore, the average level fluctuation drops from 4.4 mm to 2.5 mm and the surface velocity decreases from 0.42 m/s to 0.15m/s with the mold width rising up. The industrial experiments also show the similar trend as the results of water modeling. Accordingly, the mold level characteristic should be adjusted dynami- cally based on the slab width.