地铁道岔尖轨线型复核及矫正

Exploration of the Review and Correction of a Switch Rail Line of a Subway Turnout

地铁道岔尖轨是道岔实现转换功能的主要部件之一,尖轨线型不良不仅使列车产生晃动,也会影响与基本轨的正常靠贴和自由状态平面位置。尖轨与基本轨靠贴时存在离缝、卡阻和尖轨原始位置不准,会使尖轨失去稳定刚度和增大道岔锁闭"框动"、转换动力以及出现转换反弹现象,继而恶化通号转辙设备的工况,影响道岔的正常使用。由此,轨道专业人士应高度重视尖轨的线型控制。在实践的基础上,认真分析尖轨从生产制造、运输、存放、上道使用过程中线型发生不良变化的成因,提出相应对策措施;并介绍尖轨线型的检测复核和矫正手段。其中,首次倡导"一弦矢距法"检测复核整根尖轨线型的现状,特别针对曲线型尖轨,通过建立数学模型计算得到"一弦"条件下尖轨各检测点理论矢距值,为尖轨上道前进行预矫正提供了依据,这对地铁停运后的有限时间天窗内圆满完成尖轨更换作业意义重大。

The switch rail is one of the main components to achieve conversion function of the switch.The bad linearity of the switch rail will not only make the train shaking,but also affect the normal post and plane position of the Free State against the stock rail.The seam,blocking and inaccuracy of the switch original location exist in switch rail against the stock rail,which makes switch lose stability stiffness,increase the turnout locking "frame movement",converse power and lead to conversion rebound resulting in the deterioration of electrical switch device condition and effect on the normal use of the turnout.Therefore,rail professionals must attach great importance to the control of the rail linearity.On the basis of the practice,this article conducts a careful analysis of causes about rail bad linearity changes during the course of manufacturing,transportation,storage and use,puts forward the corresponding countermeasures and introduces the means on testing reviewing and correcting the rail linearity.Firstly,this paper advocates "one chord vector distance method"to test and check the present situation of the whole switch rail linearity.Especially for the curved rail,one mathematical model is established in order to calculate the theoretical digital value of each detection point of the rail under the condition of "one chord".It is such a value that provides the basis of the pre-correction before switch rail is on the road,which is of great significance for the successful completion of the rail replacement work within the limited time after the shutdown of subway.