Experimental study of the effect of contact line profiles on the wear mechanism of a skateboard

Abstract

Using an experimental approach, the researchers investigated the wear of a skateboard according to different profile contact lines. A high-speed current-carrying test machine was used to simulate underground railway operational conditions and obtain parameters such as the coefficient of friction, arc discharge energy, temperature increase, current-carrying efficiency, and offline rate of friction pairs comprising a skateboard and contact lines with varying profiles. The researchers analysed the impact of experimental parameters on skateboard wear matched with the different contact lines, as well as the wear mechanism of the skateboard. The experimental results revealed the following order for the total skateboard wear when matched with different contact lines: oblique contact line > pitted contact line > normal contact line. For the total skateboard wear with oblique contact line, the electrical wear of the skateboard predominantly contributed to the overall wear. Across all experiments, the total skateboard wear when matched with the oblique and pitted contact lines reached 10.291 g and 5.537 g, respectively, which was approximately 3.232 and 1.739 times the wear observed when matched with the normal contact line (3.184 g). With other experimental parameters held constant, the skateboard wear was directly proportional to current and sliding velocity, but inversely proportional to the normal load. The effect of sliding velocity on skateboard wear, arc energy, offline rate, etc., was less significant than the impact of current and normal load, especially at low speeds.