U71Mn热轧钢轨闪光焊接灰斑缺陷分析  

Analysis of Gray Defect of Flash Welding of U71Mn Hot Rolled Rail

作　　者：黎伟 Li Wei

机构地区：[1]中国铁路武汉局集团有限公司武汉工务大修段,武汉430070

出　　处：《装备机械》2023年第3期57-62,共6页The Magazine on Equipment Machinery

摘　　要：统计表明,在钢轨闪光焊接工艺中,U71Mn热轧钢轨灰斑缺陷要多于U75V热轧钢轨,一次落锤合格率U71Mn热轧钢轨较低。产生灰斑缺陷的原因是,在焊接烧化过程中形成氧化夹杂物,顶锻时未排挤出,进而残留于焊缝中,形成灰斑缺陷。对U71Mn热轧钢轨闪光焊接灰斑缺陷进行分析,并进行焊接工艺调试。通过合理设置顶锻时间、顶锻压力,能够较好控制断口呈现撕裂状。进行烧化阶段工艺参数正交试验,得出合理的烧化工艺参数组合。通过落锤和静弯试验,表明灰斑缺陷得到较好控制。Statistics show that in the rail flash welding process,the gray spot defects of U71Mn hot-rolled rail are more than those of U75V hot-rolled rail,and the pass rate of U71Mn hot-rolled rail is lower.The cause of the gray spot defect is that oxidation inclusion is formed during the welding and burning process,and it is not extruded during top forging,and then remains in the weld to form gray spot defect.The gray defect of flash welding of U71Mn hot rolled rail was analyzed,and the welding process was debugged.By reasonably setting the top forging time and top forging pressure,the fracture can be better controlled to appear teared.The orthogonal test of the process parameters in the firing stage was carried out to obtain a reasonable combination of the firing process parameters.Through the drop weight test and static bending test,it is shown that the gray spot defect is well controlled.

关 键 词：热轧钢轨 闪光焊接 灰斑 分析 

分 类 号：U213.92[交通运输工程—道路与铁道工程]