Ultrasonic Inspection for Serious Defects on Fusion Welds of Rail


Mitsumasa TATSUMI, Katsuyoshi UEYAMA, Ryuichi YAMAMOTO, Syouichi KUDOH
In Japan, four types of welding method have been used for rail welding. Among them, alumino-thermic welding and enclosed arc welding are found liable, though slightly, to cause weld defects. Therefore, ultrasonic test has been applied for their welds. However, this inspection is not practical for reliability estimation of welds. We try to reexamine the ultrasonic test standard for rail welds. As a result, it becomes clear that the grade of weld defects, which are inspected by "bottom double-probe method ", is correlated with static strength and dynamic strength of welds, and that " bottom bouble-probe method " is effective for preventing an early stage damage to alumino-thermic welds and fatigue damage, which occur in the bottom of rail, to enclosed arc welds.