起重机主梁(如工字梁,偏轨箱形梁等)的翼缘和腹板相连接的纵向角焊缝(图1)的焊透问题是生产厂当中有争论的问题。争论的焦点是:纵向角焊缝未焊透是否会导致焊缝开裂?是否会成为疲劳破坏的主要根源?以及这些焊缝在哪些情况下必须开坡口?近二十年 The penetration problem of longitudinal fillet welds (Figure 1) connecting the flanges and webs of crane girders (such as I-beams, rail box girders, etc.) is a matter of debate among manufacturing plants. The focus of the debate is whether vertical fillet welds will lead to cracking of the weld and whether it will be the main source of fatigue damage and when these welds must be beveled for nearly two decades