Experimental investigation of essential feature of polygonal wear of locomotive wheels

Abstract

Polygonal wear is a common type of wheel surface damage in rail vehicles. Drastic wheel/rail interactions can be induced by wheel polygonization, which directly influences train service performance and maintenance cost, even threatens running safety of rail vehicles. This paper presents an experimental investigation into the fundamental feature of wheel polygonal wear through extensive field measurements. A series of wheel wear measurements and locomotive vibration tests were conducted to reveal the relationship between the wheel polygonization and vibration alarm phenomenon occurred in heavy-haul electric locomotives. A post-processing method to deal with the raw data of wheel polygonization was applied. The characteristics of the wheel polygonization of the locomotives with and without abnormal vibration were compared and analyzed in detail. It is found that the high-order wheel polygonal wear is the root cause of the vibration alarm of locomotive unsprung components. To investigate the elimination effect of locomotive wheel polygonization by different wheel re-profiling methods, tracking measurements of wheel polygonal wear were conducted on three selected locomotives during an interval of the neighboring wheel re-profiling period. The results show that the wheel re-profiling method has a significant effect on the elimination and development of wheel polygonization. The high-order wheel polygonal wear of the re-profiled wheels develops slowly only if it is cleared off.