Immersion Testing of Curved Profile Objects by Surface Ultrasonic Waves

A method for testing the products with a flat and curved surface using surface ultrasonic waves in the immersion version is proposed. Theoretical and experimental studies have shown that with the length of the testing zone from $$20\lambda $$ to $$50\lambda $$ , the combined application of the echo pulse method together with the amplitude and time variants of the shadow method makes it possible to detect both cracks and defects with a smooth profile with a depth of fractions of a wavelength on flat and curved surfaces. The research results were used in the development of an automatic rail monitoring system in the production flow; its tests confirmed high sensitivity and noise immunity of the immersion testing with surface waves.