Experimental study on the wear mechanism of the contact line in rigid pantograph-catenary systems

An experimental study was conducted to assess the wear mechanism of the commonly used contact lines in rail services. A high-speed sliding electrical contact wear test machine was applied to pantograph-catenary systems (PCS). The friction coefficient, arc discharge energy, current-passing efficiency, contact resistance, and contact loss rate were recorded or calculated. The impact of the test parameters on the wear of the contact line was analyzed. Our results showed that the wear rate of the contact line was inversely proportional to the normal force and directly proportional to the sliding speed. The wear of the contact line at constant current mainly included mechanical and electrical wear. With declining system stability, electrical wear gradually became the key to determining total contact line wear. When the normal force and sliding speed were maintained constant, the wear rate of the contact line fluctuated with changes in the current. Under non-current conditions, mostly mechanical wear occurred in the contact line, and the total wear was the highest. When the current (I) was maintained at 250 A, the electrical wear of the contact line was the highest, and the total wear was the highest under current-carrying conditions. However, at I = 350 A, the electrical and mechanical wear of the contact line were both at a low level, and the total wear of the contact line was the lowest. When I was increased to 450 A, the total wear of the contact line contributed to material transfer wear based on electrical and mechanical wear. In all tests, the maximum wear rate of the contact line (6.9712 × 10−3 g/km) was 3.138 times the minimum wear rate of the contact line (2.2215 × 10−3 g/km).