地铁终点折返道岔在所有道岔设备中使用频 率最高、发生故障率最高。上海地铁运营线路中部分终 点折返道岔主要常见病害表现为尖轨侧磨致尖轨尖剥 落掉块、滑床板 （垫板 ）断裂、尖轨不密贴、支撑块碎裂 等?根据病害原因总结关于折返岔区道岔的养修标准和 方法?对提高设备使用寿命和安全系数?具有重要意义。

M etro term inalturnback turnouts are used m ost frequently and have the highest rate of failures am ong all turnout equipm ent.T his article analyzes the status and com m on faults of the term inal turnback turnouts on som e Shanghai m etro operation lines,illustrates the types and the reasons of the faults,and puts forward som e solutions to the problem .

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