Papers by Keyword: Wheel Set

Abstract: In order to make the mass distribution of the wheel set symmetrical about the axis of the wheel axle, which is able to remove the periodical exciter source and many consequences coming from it, including having negative effect on the stationarity and stability during the running of the train, shortening the lifetime of the wheels, bearings and many other parts of the train, design a set of balanced device to regulate the mass center of the wheel set. The set of device collects data by relevant detection devices in order to find the mass distribution condition, and then regulate the circumferential positions of the objects with a certain mass in the tapered groove which can make the mass distribution of the wheel set symmetrical about the axis of the wheel axle. The device has many advantages, such as simplicity, high precision, excellent regulating effects, and, at the same time, conquers the disadvantages of many other ways. For the time being, the means to solve the problem are mainly Adding Weight Method and Removing Weight Method, which both cause physical damage to the wheel. Furthermore, these two methods have a lot of disadvantages, such as low stability, limited effect, limited repairing numbers and high labor strength. The device not only conquers these disadvantages of the two methods, but also has many advantages, and in the future, it can be automatically controlled by microcomputers. Wheel sets are very essential to the running of the train, whose quality has outstanding effect on the safety and quality of the running of the train, especially in the condition that trains run faster and faster, which requires wheel sets to meet higher standards on dynamic balance, especially for new high-speed bogie. Thus, the device has a large economy benefit and society benefit.

Abstract: Wheel set longitudinal vibration is a self-excited vibration when railway vehicle is running on the track, which is one of the important reasons of wheel tread spalling problem, and will cause the dynamic performance worse of the vehicle. To investigate the happen mechanism of the wheel set longitudinal vibration, the 7 degree of freedoms wheel set longitudinal vibration model which considers the torsion vibration of the wheel axle was set up based on Matlab. From the point of view of frequency and vibration, put forward one kind of forecast method of the happen of wheel set longitudinal vibration. Wheel set longitudinal vibration will lead car body to suffer an impact in the longitudinal direction and this would cause car body tremble and have a big vertical vibration. Take the locomotive which has severe wheel tread spalling problem running on the Kunming meter track for example to test the effect of the wheel set longitudinal vibration theory to solve the wheel tread spalling problem. Solve wheel tread damage from the aspect of dynamic is an evolution method and Wheel set longitudinal dynamic is the extension of the wheel/rail dynamic.

Abstract: Aimed to wheel flange partial wear problem, the heavy haul train dynamic model was setup, and the coupler and buffer system was setup in detail. The dynamic performance of the train under the longitudinal coupler press force was simulated. The wheel/rail lateral force and wheel flange wear were analyses. Simulation results shown that the front locomotive will suffer a big longitudinal press force for the delay of the brake force transfer; this will lead the rotation of the coupler. The lateral force will apply to the car body at the position of coupler, which was caused by the longitudinal coupler force and the rotation angle of the coupler, then the wheel flange partial wear were induced as a result.

Abstract: Damage modes, causes, and effects of railway wheel set are investigated from wide production fields. And then, the reliability strategies are classified as service reliability and development reliability. The development one includes design, material and manufacturing, quality approval/authentication, which is a basis of the service one. The service one is the true product quality, which has not only the basis of development reliability but also the effects of non-destructive monitoring level, damage analysis and assessment capacity, and repairing and renewing policies. Reliability of wheel set is so important that a series of code-based regularities have been issued by professional societies or associations. Optimal design is a most effective way to improve wheel set reliability. And in service, non-destructive inspection and repair opportunities are valuable to be synthetically programmed. The critical damage defect/flaw sizes should be scientifically determined. Three advances in strength reliability field should be introduced. They are affordable and appropriate method for reliability assessment and fatigue life prediction including the super long life regime, no-Paris type crack growth models which include crack initiation, stable growth, and approach fracture, and fatigue S-N relation derived from short cracking growth behaviour.