Through analyzing of the crackle sample of swing hanger cross beam of 209T bogie. This paper finds the reason of causing crackle ,at the same it gives some advanced opinions.

• 通过对209T型转向架摇枕吊销裂纹试样进行金相组织分析，得出摇枕吊销表面裂纹产生的原因，并提出改进意见。