Wheel Diameter Difference Research Articles

High-speed EMU wheel re-profiling threshold for complex wear forms from dynamics viewpoint

On-site monitoring on wear of EMU wheel tread was conducted on some high-speed railway lines. The data indicates that hollow wear is the main wear form in the high-speed EMU wheels with complicated side-wear. The detrimental influences of different wear forms on the vehicle dynamic behaviors were studied using the vehicle dynamic model that was established based on the real vehicle parameters. The results show that there are two wheel/rail equilibrium positions on wheel tread when the hollow wear occurred. When the vehicle is running at high speed, the wheel/rail contact point jumps from one equilibrium position to another leading to “flange to false flange” vibration, which can significantly affects the vehicle dynamic behavior. Negative equivalent conicity occurs on condition of wheel side-wear, which leads to the equilibrium position of wheelsets offset from the middle of the track and the vehicle running quality is deteriorated. The hollow-worn wheels can provide some wheel diameter difference, which is beneficial to the vehicle curve negotiation. Compared with the reversed phase side-wear, the wheelsets with in-phase side-wear have greater influence on the bogie stability and riding quality. Taking the vehicle running stability and curving behaviors into consideration, the re-profiling threshold was determined for the complex wear forms.

Influence of Wheel Diameter Difference on Wheel/Rail Interaction of Locomotive under Coasting and Electric Braking Conditions

Influence of Wheel Diameter Difference on Wheel/Rail Interaction of Locomotive under Coasting and Electric Braking Conditions

Influence of Wheel Diameter Difference on Safety and Stationarity of Vehicles Crawling over the Curved Bridge

Wheel diameter difference has great impact on the operation performance of vehicles which are traveling on the curved bridge. A simulation analysis model was built to analyze the influence of wheel diameter difference on safety and stationarity of vehicles on the curved bridge. The results demonstrate that along with the increase of wheel diameter difference, the security of vehicles on the curved bridge decreases and the vehicles run unsteadily. So the wheel diameter difference should be diminished as much as possible, especially strictly controlling the wheel diameter difference of high-speed vehicles.