汽轮机联轴器断齿原因分析

Cause analysis of broken teeth of steam turbine coupling

通过宏观检查并结合直读光谱仪、金相显微镜、维氏硬度计等检测分析仪器,对汽轮机联轴器断齿原因进行分析。结果表明,联轴器断齿原因主要与轮齿自身硬度梯度过大及轮齿受力不均有关;联轴器轮齿表面渗氮处理不充分,造成材料表面渗氮层厚度较薄,使得轮齿上硬度梯度过大,轮齿表面的渗氮层在应力作用下破裂、脱落,暴露的基体不耐磨,轮齿发生断裂。

By means of macroscopic inspection and combined with direct reading spectrometer,metallographic microscope,vickers hardness tester and other testing and analysis instruments,the cause of broken teeth of steam turbine coupling was analyzed.The results show that the causes of coupling teeth breakage were mainly related to the excessive hardness gradient of the gear teeth and the uneven stress of the gear teeth.Insufficient nitriding treatment on the surface of coupling gear teeth caused the thickness of nitriding layer on the material surface to be thin,which resulted in excessive hardness gradient on the gear teeth.The nitriding layer on the gear teeth surface broke and fell off under the action of stress,the exposed matrix was not wear-resistant,and the gear teeth broke.