Dynamic Detection of Wheel Tread Crack Based on Eddy Current Pulse Thermography

Wheels are one of the key parts of train. Rolling contact fatigue cracks caused by frequent rolling contact with steel rails will seriously damage the safety of wheels. Non-destructive testing of wheels is essential to ensure the safety of train operation. Therefore, this paper has researched on the dynamic detection of wheel tread cracks based on eddy current pulsed thermography (ECPT). In this paper, the ECPT wheel dynamic detection system is built firstly, and the wheel tread crack detection data is collected through the system. Subsequently, this paper analyzes the distribution law of the temperature near the crack in the detection data, determines the best scan line position, and realizes the crack visualization through the scan line position and the line scan method (LSM). Finally, this paper proposes a quantitative method of crack length for dynamic detection of ECPT. This method is only suitable for the situation where the crack direction is the same as the wheel turning. The test results show that dynamic detection of ECPT can effectively detect wheel tread cracks, and the crack length quantitative method can effectively quantify the wheel tread crack length.