Nondestructive Evaluation of Hoop Stress in Rolling Stock Wheels

Kenji KASHIWAYA, PhD., Senior Chief Engineer, Materials Technology Development Division, Technical Development Department
Hiroshi SAKAMOTO, Engineer, Strength Evaluation & Inspection Group, Vehicle Technology Development Division, Technical Development Department
Shingo YOSHIDA, Engineer, Technical Development Group, Shinkoiwa Rolling Stock Works, Japan Freight Railway Co.Ltd.

For the prevention of a wheel break, resulting in derailment, the hoop stress in a wheel which might be heated due to braking trouble should be measured nondestructively and a wheel that is found with a large tensile hoop stress should not be used. The magnetostriction stress measuring method, which is able to easily measure a residual stress on the surface with a small sensor, is applied. A measuring site where the hoop stress can be evaluated well is sought and the most suitable site is located inside the rim near the standard groove. Comparison of measured results by the referenced method and those by a destructive method shows a good correlation between the two. After measurements of many wheel, the referenced method is confirmed to be able to evaluate the hoop stress in wheels.