Solution approach:
To increase the signal strength, it was necessary to modify the wheel disc geometry by machining. By weakening the disc rotationally symmetrically, the necessary signal strength can be achieved to meet the requirements in terms of measurement accuracy. In order to determine the necessary change in contour, preliminary studies were carried out using various approaches and then tested for their suitability. From the knowledge gained from these studies, it was possible to find a suitable wheel disc geometry and to determine an optimum positioning and interconnection of the strain gages. Finally, a strength assessment according to EN 13979 was performed for the modified geometry to ensure that the structural strength of the wheelset is still sufficiently guaranteed after weakening.
Results:
By carefully testing different wheel disc geometries, we were able to find an optimal contour that provides a sufficiently high signal strength and at the same time, with a modified wall thickness of less than 50% of the original one, does not show any significant change in the peak values of the stress amplitudes in the wheel disc.
Our customer was thus able to build measuring wheelsets that deliver high-quality measuring signals and still have the necessary strength, so that safe operation for the test runs was guaranteed.
