Experimental Research On Sliding Electrical Contact Friction Characteristics Of Pantograph Contact Strips

In order to research the pantograph strip and contact wire friction and wear properties, develops a high-performance sliding electrical contact testing machine. It can achieve uniform wear between pantograph strip and contact wire. In a certain range, it can realize current, load, speed, single-and multi-factors control, to implement real-time online surveying of contact wire and slide friction coefficient,the number of pantograph contact strips reciprocating mobile, wear volume of contact wire and pantograph contact strips and so on. Simultaneously realizes the data preservation. Based on the LabVIEW designs monitor screen and the data processing system.With the testing instrument on high-performance sliding electrical contact,studies the wear degree of influence, which the pressure, sliding speeds and the currents exert to the metal impregnation carbon strips, and determines the experimental scheme which is orthogonal experimental method. The result shows that the degree of current influence is the greatest. Take Cu-base powder metallurgy strip and copper tin wire as friction,those experiment results were analyzed by introducing two relative stable coefficients, some rules between the above characteristics of slide and contact pressure, sliding speed and contact current were obtained. Under constant sliding speed conditions, the friction coefficient increased with the increase of contact pressure, but both the property of current-carrying and the friction stability are improved. So, the curve of wear rate and contact pressure is a U-shaped curve. It's showed the wear rate firstly decrease and then increase. The threshold of contact corresponds to minimum wear rate will increase with the increase of contact pressure. Under constant pressure conditions, the friction coefficient will decrease with the increase of sliding speed, while both the property of current-carrying and the friction stability are deteriorated. The wear rate will decrease with sliding speed and increase with contact current.