The Solution for Volumetric Assessment of Aluminothermic Rail Welds

There are millions of aluminothermic welds made eac h year to join rail in Europe’s rail network and mi llions are already in-service. Occasionally flaws develop duri ng and shortly after welding and this can lead to e arly failure therefore causing disruption to train services and costs to both the train operating companies and the maintenance operators. Although radiographic inspec tion is sometimes carried out, this is not very com mon, and the conventional ultrasonic standard requires many probes and scans because of the complex geometry of the rail profile. Since the welds are made by a casting proc ess, these can be more difficult to inspect than jo ints made by other welding processes. Hence, the RAILECT project was conceived to provide a convenient means of inspecting the joints using a multiple phased array ultrasonic system. This article describes the type of flaws concerned, the modelling of the ultrasonics, the practical re alisation of a prototype system and the development of acceptance criteria.