A prototype instrument to evaluate fatigue damage in the sidewalls of steel-belted radial truck tires

Using the acousto-ultrasonic approach, a prototype instrument capable of detecting and evaluating ply cord fatigue damage, which is a likely cause of the zipper mode of failure in radial steel belted truck tires, has been developed. The instrument has the potential to be production oriented and capable of being used for on-line inspection of new or used tires. The instrument is capable of producing color-coded scans, thereby reducing the possibility of operator error that could result in damaged tires being placed in service. Results for two tires, one with seeded defects and the other with field fatigue damage, are presented and discussed.