重载机车车钩自由角对轮轨动态安全性能的影响

Effect of the Coupler Free Angle on Wheel/Rail Dynamic Safety Performance of Heavy Haul Locomotive

为了探明重载机车车钩自由角对机车运用安全性能的影响规律,运用大系统动力学理论,仿真计算相同制动速度不同车钩自由角、不同制动速度相同车钩自由角时的轮轨动态安全性能标。结果表明:在相同初始制动速度(80 km.h-1)条件下,当车钩最大自由角为3°时,轮轨动态安全性指标满足运行要求,轨距动态扩大量较小,轮轨接触点分布正常;当车钩最大自由角为4°时,则轮轴横向力不能满足安全运行要求,轨距动态扩大非常明显,出现了轮缘和钢轨侧面接触、轮轨接触点集中等异常现象。车钩最大自由角为3°时的制动初始速度的安全限值为82 km.h-1。计算结果与实际运用得出的结论一致。

In order to investigate the influence law of the coupler free angle on the running safety of heavy haul locomotive, the wheel/rail dynamic safety indices were calculated and analyzed by means of coupling dynamics theory. Two kinds of hypothetic conditions were taken into account in the process of calculation, one was the different free angle with the same brake speed, and the other was the different brake speed with the same free angle. Calculated results show that under the condition of the same initial brake speed of 80 km· h^-1 and the maximum coupler free angle of 3°, the wheel/rail dynamic safety indices meet the operation requirements, and the dynamic enlargement of the gauge is smaller and the distribution of wheel/ rail contact point is normal. When the maximum coupler free angle is 4°, the lateral force of the wheel axle cannot meet the requirements for safety operation. The dynamic enlargement of the gauge changes obviously and there are some abnormal phenomena occur such as the contact between the wheel flange and rail, and the wheel/rail contact points are concentrated etc. If the maximum coupler free angle is 3°, the safety limit value for the initial safety brake speed is 82 km·h^-1. The calculated results agree with the conclusions from the actual applications.