组合式结晶器内连铸坯皮下气泡的形成

Formation of Subcutaneous Blow Hole of Casting Slab With Composite Mould

通过对有关文献的评述,讨论了连铸板坯皮下气泡的形成原因和分布特点,说明连铸过程中组合式结晶器角缝中上升气流吹入钢水可造成连铸坯皮下气泡。降低钢水过热度、降低拉速以促使结晶器内钢水尽快形成稳定坯壳,从而可以抵抗气流吹入,减轻皮下气泡的形成。由于在组合式结晶器内连铸坯皮下气泡的产生是难以避免的,所以棒材生产线的方坯连铸机不宜采用组合式结晶器,采用管式结晶器是当前的发展趋势。

By commenting on the relevant references, the forming reason and distribution of the subcutaneous blow hole in the continuous cast slab was discussed. During continuous casting the rising air current in the corner gap of the composite mould blowing into the liquid steel will cause the formation of the subcutaneous blow holes in the slab. Lowering the temperature of the liquid steel and lowering the drawing speed can alleviate the subcutaneous blow holes by forming stable slab shell quickly so as to prevent the air from blowing in. It is unavoidable for the subcutaneous blow holes in the slab to be formed when casting with composite mould, so it is unsuitable for the composite mould to be used for the continuous casting of the bloom for the production of rolled bars. At present the using of tubular mould is a trend.