受电弓下框架与降弓驱动机构连接支架裂纹原因分析及处置措施

Cause Analysis and Treatment Measures of Cracks on Connection Bracket between Pantograph Lower Frame and Depowering Mechanism

受电弓为车辆核心部件,其状态攸关行车安全。以上海轨道交通某型受电弓为例,介绍了受电弓下框架与降弓驱动机构连接支架处裂纹情况;通过对开裂试样的材料成分、断口形貌、结构强度等进行分析,结果显示连接支架结构设计缺陷及焊接质量不佳是导致受电弓下框架与降弓机构连接支架处疲劳开裂的主因。针对性采取了优化连接支架结构、尺寸以及焊接工艺等措施,优化结构通过了台架试验及试运营考核。优化结构具备批量整改及装车服役条件。

Pantograph is a crucial component of the vehicle,and its condition is closely related to the safety of train operation.Taking a certain type of pantograph in Shanghai rail transit as an example,the cracks on the connection bracket between the pantograph lower frame and the depowering mechanism is introduced.By analyzing the material composition,fracture morphology,and structural strength of the cracked specimens,the results indicate that structural design defects and poor welding quality are the main causes of fatigue cracks on the connection bracket.Targeted measures are implemented,including optimizing the connection bracket structure,dimensions and welding process.The optimized structure passed the bench test and operational evaluation.It is suitable for batch rectification and deployment in service conditions.