连铸坯轧重轨的压缩比及帽形孔和切深孔的应力场分析

对某厂所使用的重轨孔型自切深孔以后的轧件压缩比进行了分析，对帽形孔和切深孔中沿轧件横断面上的应力场分布进行了弹塑性有限元计算机模拟。结果表明，用连铸坯取代初轧坯，如果坯形和孔形不进行相应的改变，轧件轨头和轨底的压缩比小，难以确保重轨的质量。现有的孔型，沿轧件的横断面上，局部位置存在着较大的拉应力。使用初轧坯，这种拉应力对产品质量的影响不大。但对于连铸坯，如果坯形和孔型均与初轧坯相同，轧件有产生内部缺陷的条件。

REDUCTION RATE AND STRESS FIELD IN THE HEAVY RAIL ROLLED WITH HAT PASS AND CUTTING-IN PASS FROM CONTINUOUSLY CAST BLANK

The rolling reduction rate after cutting in to the finish pass was studied for continuously cast blanks The stress field after hat pass and cutting in pass were analyzed by Finite Element Method The conclusion is as follows: In case of replacing bloom from ingot by continuously cast blanks, if the blank size and pass schedule is not changed correspondingly the reduction rate is smaller, the quality of rail head and heavy rail bottom is not ensured With the existing hat pass and cuttign in pass, there is a tension stress in heavy rail cross section, which can be neglected for the heavy rail rolled from the blooms, but for the heavy rails rolled from continuously cast blanks, this tension stress deteriorates the heavy rail quality