The non-elastic electrical contact between pantograph strip and wire, via a pantograph-rigid catenary system, results in much wear of metro strip. Every month, hundreds of thousands of strips are consumed in China due to the approximately 9900 kilometers of metro distance. Numerous instances of abnormal strip damage have been observed at the site, likely attributable to the uneven wear of strip. However, the cause of uneven wear on metro strip remains unclear to date. Hence, a wear model was developed based on the thermal equilibrium and wear mechanism, to investigate the uneven wear of strip in metro system. Various parameters, including contact force, electrical current, velocity, and copper content of the strip have been studied to explore their relationship with strip wear. Different laying structures, such as sine, half-wave, and folded line, exhibited varying degrees of uneven wear on the strip surface, with maximum depths observed at 4.20 mm per 104 km, 3.68 mm per 104 km and 1.02 mm per 104 km, respectively. The contact force holds the dominant position in metro wear, followed by current. Additionally, the wear rate also demonstrated sensitivity to the copper content of the strip.
Read full abstract