Ever since the inception of using ultrasonic technology as a method for detecting internal cracks within rail steel, the industry has relied on fixed position transducers. These transducers are positioned to scan the head and web of the rail at various degrees to detect typical cracks and fissures. The design of the probes have historically relied on new, full-ball rail as a sample specimen to verify inspection angles and coverage. However, it is commonly known that rail steel will deform and have wear patterns introduced into the running surface as train traffic traverses over the tracks. Since the rail is no longer at the ideal profile that the probes were designed to inspect, the sound path is altered and could result in non-coverage of the desired target areas. A novel approach using phased array technology measures the profile of the rail and digitizes the results. This digital profile, which is a reflection of the wear patterns of the rail, is fed into the focal law calculators and a corrected inspection beam is formed to compensate for the wear on the running surface. The result is a more consistent test that has produced accurate results. As a bonus, the digitized profile data can be rendered into a 3-D image with the ultrasonic data overlaid within the image, providing the user with a more comprehensive look at the possible reflector.

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