往复压缩机曲轴断裂失效分析

Analysis of the Fracture and Failure of Reciprocating Compressor Crankshaft

通过对已断裂的往复压缩机曲轴服役情况调查和断口裂纹宏观分析,发现曲轴受轴向拉应力和扭转载荷共同作用,其断裂不在常见易断的应力集中圆角区;通过扫描电镜进行裂纹断口微观分析,同时进行了化学成分分析、金相分析和机械性能分析,能够判断该曲轴属于典型疲劳断裂,且曲轴本身无明显致裂的因素;该压缩机在服役初始的过载事故应该导致了曲轴的初始损伤,在三年服役过程中损伤不断积累以致断裂。

Through the investigation and observation of the broken reciprocating compressor crankshaft,the fracture of the crankshaft was not in the common stress concentration fillet area under the combined action of axial tensile stress and torsion load.The fracture microscopic analysis was carried out by scanning electron microscope,and also the chemical composition analysis,metallographic analysis and mechanical property analysis had been done,these analysis displayed that the crankshaft was a typical fatigue fracture with no crack quality factor.The initial overload accident of the compressor in service should lead to the initial damage of crankshaft,and the damage accumulated continuously during the three-year service,resulting in fracture.