Abstract: 6  Soft reduction stands are installed at each strand of 6 strands caster for 280 mm×380 mm bloom. The soft  reduction  in  height  of  bloom  is  ≤8  mm  wih  reduction  rate≤1.5mm/m.Results  showed  that  with  suitable  process conditions and using dynamic soft reduction technology, the center porosity of bloom was improved led to obviously improve the  center  stripe  at  waist  of heavy  rail  of steel  U75V, and  the  rejection  rate  by  non-destructive  testing  decreased  from 0.206%  to0.095%  due  to  improvement  of distribution  of inclusions  in  bloom.

摘要： 6流280mm×380mm连铸机每流安装6架轻压下机。铸坯轻压下量≤8mm,压下率≤1.5mm/m。结果表明,在合理的工艺条件下,通过轻压下可显著改善铸坯中心疏松,从而改善U75V钢重轨的轨腰中心条纹。因改善夹杂物在铸坯内的分布,探伤次品剔出率由0.206%降至0.095%。

关键词: 大方坯连铸, 重轨钢, 动态轻压下, 疏松, 夹杂物