风电双头螺柱失效分析

Faliure analysis of wind power studs

通过近几年的失效分析总结,风机叶片上的连接螺栓失效事件时有发生,其中常见的一种情况就是螺栓螺纹根部被腐蚀出腐蚀坑,加剧了螺纹根部的应力集中,导致螺栓萌生疲劳源。本文通过宏、微观分析,腐蚀产物分析、化学分析、力学性能分析、显微组织分析等试验手段进行分析验证,结果表明虽然该失效螺柱化学成分不合格,冲击吸收功低于标准要求,但萌生疲劳源的主要因素是螺纹根部产生了腐蚀坑。

Through the failure analysis in recent years, it is concluded that the failure of the connecting bolt on the fan blade often occurs. One of the common situations is that the roots of the bolt thread are corroded out of the corrosion pits, which increases the stess concentration at the root of the threads and causes the bolts to generate fatigue sources. In this paper, macroscopic analysis, microscopic analysis, corrosion products analysis, chemical analysis, mechanical property analysis, microstructural analysis and other experimental methods are used to verify. The results show that although the chemical composition of the failed stud is unqualified, the impact energy is lower than the standard requirement, but the main cause of the source of fatigue is the formation of corrosion pits at the root of the thread.