Acoustic Emission Checking of Welded Rail Joints

The reliability of bonded railways depends on the quality of rail joints. In this article the possibility of the rail joint testing by the acoustic emission (AE) method is analyzed. The rail bondings welded by alumina-thermic and electric contact methods are examined. The program for testing rails welded by alumina-thermic method consisted of two stages. At the first stage, the applied load was increased step by step till the rails were led up to the destruction. At the second stage, the rail joints were exposed with the repeat-static bending loading. It is shown that welding defects may be detected with the parameter named criterion. For rails bonded by electric contact method AE parameters were measured during the process of welding. It is showed that four main stages of welding may be singled out. AE method makes it possible to check the stages and detect the deviation from the standard welding procedure