基于有限元模拟方法的导管开裂分析

Conduit Cracking Analysis Based on Finite Element Simulation Method

不锈钢导管在固定卡箍位置发生开裂。对断裂导管的安装位置、结构特点及装配情况进行检查,结合宏观观察、断口分析、化学分析、金相检查以及有限元模拟等方法,对其开裂原因进行分析。结果表明:导管的开裂性质为高周疲劳断裂;疲劳裂纹起始于导管外侧的机械损伤部位,导管受弯曲振动载荷作用,在导管应力集中处萌生疲劳裂纹,进而疲劳扩展。建议在对导管零件进行操作时,要严格按照有关要求进行,避免非正常受力带来的机械损伤。

The stainless steel conduit cracked at the position of the fixed clamp band during service.The installation position,structural characteristics and assembly of the fractured conduit were inspected.The cracking cause of the conduit was analyzed in combination with macroscopic observation,fracture surface analysis,chemical analysis,metallographic inspection,and finite element simulation.The results show that the cracking property of the conduit is high-cycle fatigue fracture.The fatigue crack originated from the mechanical damage part outside the conduit.The conduit was subjected to bending vibration load,and the fatigue crack initiated at the stress concentration of the conduit,and then the fatigue propagates.It is recommended that the operation of conduit parts should strictly follow the relevant requirements to avoid mechanical damage caused by abnormal force.