面向廓形质量的钢轨打磨模式优化决策方法

Optimal decision method of rail grinding pattern oriented to rail profile quality

钢轨廓形质量对轮轨关系和列车运行品质具有重要影响。为解决打磨作业施工过程中钢轨打磨模式决策规范性差及个性化程度低的问题,提出一种面向钢轨打磨廓形质量的打磨模式优化决策方法。为了准确描述服役条件下的钢轨现有廓形,以钢轨廓形离散点数据为基础,采用NURBS曲线拟合方法对打磨前的钢轨廓形进行参数化建模。引入钢轨廓形质量指数对打磨后的钢轨廓形质量进行描述,推导钢轨打磨断面廓形与打磨目标廓形的偏差求解函数关系,采用方向包围盒和区间迭代算法对钢轨打磨廓形质量指数进行精确求解。分析打磨砂轮对待打磨钢轨的作用机理,将多砂轮单角度的打磨过程转化为单砂轮多角度打磨,以砂轮摆角、排列顺序及打磨功率为变量,通过砂轮底面与钢轨断面廓形的数学接触关系模拟多个砂轮对同一钢轨断面的打磨过程,实现了砂轮组合作用下的钢轨打磨廓形曲线与廓形质量指数的预测。以钢轨打磨廓形质量指数为目标,结合钢轨打磨模式参数,设计面向钢轨廓形质量的打磨模式优化决策模型和算法方案。在此基础上,采用本文方法进行了钢轨打磨模式优化决策现场实验,结果表明,该决策优化算法可以从钢轨打磨模式库中有效筛选出最优打磨方案,大大减少人工实验成本,有效控制和提升钢轨打磨质量,实现钢轨最优打磨模式的科学决策。

The quality of the rail profile has an important influence on the wheel-rail relationship and the train operation quality. In order to solve the problems of poor standardization and low degree of individualization of decision on grinding mode, a grinding mode optimization decision method based on rail grinding profile quality was proposed. In order to accurately describe the existing profile of the rail under service conditions, based on the discrete point data of rail profile, the NURBS curve fitting method was used to model the profile of the rail before grinding. The rail profile quality index was introduced to describe the rail profile quality after grinding, and the function relationship between the deviation of the rail grinding section profile and the grinding target profile was deduced, and the directional bounding box and interval iterative algorithm are used to accurately solve the GQI.The action mechanism of the grinding wheel for grinding the rail was analyzed, and the grinding process of single-angle grinding wheels was converted into multi-angle grinding wheel. The mathematical relationship of the contact between the grinding wheel and the rail profile when the grinding train acts on the rail was extracted, and a rail grinding profile prediction algorithm was designed accordingly, which realized the rail grinding profile prediction under different grinding modes. By taking the rail grinding profile quality index as the goal, combined with the rail grinding mode parameters, the grinding mode optimization decision model and algorithm scheme were designed. On this basis, the on-site experiment of rail grinding mode optimization decision was carried out using this method. The field test results show that the method can effectively select the optimal grinding scheme from the grinding mode database, greatly reduce the cost of manual experiment, effectively control and improve the quality of rail grinding, and realize the scientific decision of rail optimal grinding mode.