Modern innovations on the application of the rotating ultrasonic probe to in-service inspection of freight solid axles: experiments and MAPOD approach

The present scenario of freight applications in Europe is characterized by a trend towards rolling stock renewal and new approaches to periodical inspection and maintenance. A specific ultrasonic technique, based on more than 40 years of service experience on passenger wheel-sets inspection, is here proposed for periodical NDT on freight wheel-sets. In the present research, a Model-Assisted Probability of Detection approach is considered. In particular, the derivation of the Probability of Detection curves of the rotating probe and an optimization of its calibration block are carried out considering both experimental tests and numerical simulations.