Abstract: SC350 switches are difficult to maintain and have a high failure rate due to factors such as complex structure, densely located connection parts, and difficult adjustment. This paper analyzes and discusses the typical problems encountered during the maintenance of this type of switches, such as the high rebound force of the switch rail, switch gap, asynchronous switch point closure, and improper closure of the point frog. Based on on-site maintenance practices, measures are proposed mainly from the perspective of electrical maintenance, including distinguishing the source of the rebound force of the switch rail, relieving the stress on the frames, standardizing the adjustment of the throw of switch , and inspecting the relative state of the point frog, in order to reduce the failures of this type of switches. Through practical application of the aforementioned methods and measures, the failure rate of the SC350 switches has been significantly reduced. These analyses and maintenance suggestions are of great significance for enhancing the reliability and safety of the application of the SC350 switches.

Key words: SC350, double slip switches, external locking switching device, typical problem, electrical maintenance

摘要： SC350型道岔因结构复杂、联结零件密集、调整难度大等因素，导致维护难度高、故障率高。针对该型道岔在维护中遇到尖轨反弹力大、虚开、密贴不同步以及心轨密贴不良等典型问题，进行分析探讨。基于现场维护实践，从电务维修角度提出包括区分尖轨反弹力来源、释放框架应力、规范调整动程以及检查心轨相对状态等方法措施，以降低该型道岔故障率。通过实践，采取所述方法措施后，SC350型道岔故障率显著降低，这些分析和维护建议对提升SC350型道岔运用可靠性和安全性具有重要意义。

关键词: SC350型, 复式交分道岔, 外锁闭转换设备, 典型问题, 电务维护