多流中间包导流孔对钢液流动轨迹的影响

Effect of Diversion Hole on Flow Trajectory of Steel in Multi-Strand Tundish

通过采用水模拟试验对多流中间包不同控流形式进行全因素试验，研究并探讨了导流孔不同流向和不同孔径对钢液流动轨迹和多流间差异性的影响；并在工厂对改进前后的导流孔进行对比试验，研究了导流孔对夹杂物行为的影响。研究结果表明：为使钢液能充分利用中间包空间并兼顾钢液向各个出水口流动的均匀性，导流孔应分为主流孔和调节孔。主流孔流向的矢量终点应在内外侧出水口中心垂线的中点，孔径为48-52mm；调整孔流向的矢量终点应在距纵向包壁前顶点175-220m／n，导流孔面积应在中间包浇注末期仍能保证通钢量的需求。导流孔经改进后钢液在中间包内的停留时间平均增加25％，铸坯中大夹杂物含量减少64．2％；活塞流体积平均增加50％，两流间差异性减小60％，中间包内WT[O]降低16．4％。

Water model experiment was adopted to study the effect of diversion hole with different direction and area on flow trajectories of liquid steel and difference of multi-stand. Furthermore, the contrast test between the original and new tundish was carried out in the plate, the effect of flow behavior of steel on removal rate of inclusions was also investigated. The result show that： in order to make full use of space of liquid steel in tundish and uniformity of each nozzle flow, diver- sion hole should be divided into main hole and revision hole. The end of vector of flow direction of main hole should be in the middle of vertical line of tie line of strand 1 and strand 2, the diameter of main hole should be 48 to 52 mm; and the end of vector of flow direction of revision hole should be 175 mm to 220 mm away from first-top point of longitudinal wall and the steel flow of outlet at the end of casting should be satisfied with proper area of revision hole. When diversion hole is utilized, the average resident time of steel increases by 25%, the amount of macro inclusions in slab decreases by 64.2%; plug volume of steel increases by 50%, the difference between strand 1 and 2 decreases by 60%, WT[O] in tundish decreases by 16.4%.