Study on wear performance and mechanism of pantograph contact strip that contact with damaged contact wire under ambient humidity

Studies have focused on the significant impact of contact wire damage on the abnormal wear of pantograph contact strips. Initially, on the basis of field data analysis, the most common types of contact wire damage were identified. The experiments and wear performance analysis of contact strips in contact with damaged contact wires were subsequently conducted at high and low humidities. Finally, correlation analysis was employed to explore the influence of various factors on strip wear performance. The results indicate that excessive wear occurs on the contact strip with the pitted contact (PC) wire, particularly under low humidity, where the strip wear rate is 2.2 times greater than that of the contact strip with the normal contact (NC) wire. While in contact with a PC, the primary wear mechanisms of the contact strip include material transfer and arcing ablation under high humidity but involve material transfer, arcing ablation, and microcutting under low humidity. Correlation analysis revealed that under low humidity, the parameters related to PC had the greatest impact on the wear rate of the contact strips, with a significant increase in the mechanical wear proportion. On the basis of these findings, both contact wire damage and reduced humidity contribute to more severe abnormal wear of the contact strip, with the influence of PC conditions being more excessive than that of reduced humidity on wear performance.