Research on Correlation of Wheel Bending Fatigue Testing Machine Based on Wohler Curve

Because the control systems and equipment structures of two automobile wheel bending testing machines from different manufacturers are different, even if the force sensors and speed sensors of the equipment are calibrated consistently, the bending moment values output to the wheels will be different, thus affecting the test results, which is a common phenomenon in the wheel industry. So in order to verify the difference between two automobile wheel bending testing machines from different manufacturers, it is particularly important to find the correlation between the equipment. Firstly, 10 wheels were tested on two equipments, and the cycle times and crack positions of the wheels when the two equipments stopped were obtained by setting the same shutdown conditions, thus the difference of the cycle times between the two equipments was obtained. Then, strain gauges are attached to the crack-prone positions with new wheels of the same batch, and strain data are collected on two devices with the same strain wheel, so as to obtain the strain difference between the two devices. At last, based on the concept of rain flow cycle counting, the cumulative damage results of two dynamic bending fatigue testing machines were calculated by us-ing nCode software, and the cumulative damage difference between the two devices was obtained. The cumulative damage difference between the two devices verified the accuracy of the difference in wheel cycle times, and the relationship between the two devices was deduced by Wohler curve formula.