切胶机在投入使用不到两个月其液压缸连接轴即发生断裂。采用化学成分分析、金相检验、力学性能检测和断口分析等方法对断轴进行了分析。结果表明,该连接轴属于疲劳断裂。尽管该轴工作过程中承受着往复的拉压作用,但与一般拉压工作条件下轴的拉压疲劳断裂机理不同,导致该连接轴疲劳断裂的主要原因是工作过程产生的不断变化的弯曲应力。

The copular axle for cutting rubber machine was broken when the machine was being used. It caused a fatal accident resulting in a worker endured. In fact,the total operating time of the machine was less than two months. The test and analysis were made by means of chemical composition analysis,mechanical properties testing,metallographic examination and fracture analysis. As expected,the analysis result was proved that it was the fatigue fracture. The analysis showed that the fracture of axle was caused by bending stress resulted from cutting course,though the shaft endured strength and press stress during its runing.