适用于轮缘增厚现象的机车车轮镟修模型研究与应用

Research and application of locomotive wheel reprofiling model targeting flange thickening

机车车轮轮缘厚度是车轮尺寸的重要参数。近年来,轮缘增厚超限的问题尤为突出,不仅增加了检修成本,降低了机车周转率,而且过多的镟修损耗在一定程度上降低了车轮的使用寿命。文章首先分析了轮缘增厚的原理,发现测量标准的改变和机车运行线路条件的改善是主要因素;随后基于标准中规定的薄轮缘踏面外形,构建轮缘减薄模型,结合轮缘实际变化情况分析每个车轮的最佳薄轮缘踏面外形镟修方案;再在经济化镟修模型上加入轮缘减薄模型,综合考虑车轮初始镟修量、轮径差要求等影响因素,确定车轮镟修的轮缘厚度、镟修量、镟修顺序、镟修工艺要求等技术指标,实现车轮镟修的定制化方案,拓展了经济化镟修模型应用范围。基于改进后的车轮镟修模型搭建应用系统,通过对机务段中机车车轮的试点应用,以及对改进后模型的实际验证,在两个月的试点中轮缘减薄处理比例占到78%,平均减薄0.83 mm,单片车轮平均镟修量下降了7.94%。由验证结果可知,该模型不仅可以降低轮缘增厚机车的镟修比例,提高机车的周转率,而且能够有效降低车轮的平均镟修量,延长车轮使用寿命,具备推广应用价值。

Flange thickness is an important parameter measuring wheel size of locomotives. In recent years, the problem of flange thickening over the specified limit has become particularly prominent, which not only increases the maintenance cost, but also reduces the locomotive turnover rate. Moreover, excessive losses due to reprofiling bring an adverse effect to the service life of wheels. In this paper, the principle of flange thickening was firstly analyzed, and it was found that the change in measurement standard and the improvement of locomotive operating track conditions are the main influencing factors. A flange thinning model was built based on the wheel tread contours with thin flanges specified in the Chinese railway standard, and analysis was performed in consideration of the actual flange change of each wheel, to generate the reprofiling plans to maintain their wheel tread contours with the optimum flanges. In addition, the flange thinning model was added to the economical reprofiling model, and the technical indicators such as flange thickness, reprofiling amount, reprofiling order, and reprofiling craft requirements were determined, integrating the factors such as the initial reprofiling amount and the requirements of wheel diameter difference into account, such achieving customization for wheel reprofiling plans,and expanding the application scope of economical reprofiling model. An application system was built based on the improved wheel reprofiling model, which was applied in trial to the locomotive wheels at the depot, and the improved model was verified in actual conditions. In the two-month trial application, flange thinning reached a proportion of 78%, with an average thinning of 0.83 cm and the average reprofiling amount per wheel down by 7.94%. It can be seen from the verification results that the model can not only reduce the reprofiling proportion of locomotives with thickened flanges, thus improving the turnover rate of locomotives, but also effectively reduce the average reprofiling amount of wheels, to prolong their service life, demonstrating the value of promotion and application.