为了探讨往复式压缩机气阀的无损故障诊断技术,对3Cr13不锈钢气阀试样进行连续加载的拉伸试验,利用声发射技术对其拉伸过程中的损伤线定位声发射特性、断裂声发射特性进行分析,并采用S3400型扫描电镜进行断口形貌分析.试验结果为:气阀试样在距离3号佳感器30 mm处出现较强声发射峰,在拉伸时间为175.5 s时,试样发生断裂.气阀试样在承受83 kN拉力时,试样表面呈现规则的层状形貌.当3Cr13不锈钢气阀试样的挠度为0.48和0.74时,气阀试样的振铃计数分别为3.7×103和27.1×103个.在3Cr13不锈钢气阀试样断口上有大量微裂纹,是断裂过程中产生幅度为43~80 dB信号的主要原因.在3Cr13不锈钢气阀试样断口表面,其主要成分为Cr元素,其重量百分比含量为13.8%.

In order to study the non-destructive fault diagnosis technology of reciprocating compressor gas valve,the linear location and breaking-down process acoustic emission characteristics of the valve samples were investigated by using acoustic emission technology in this paper.And the fracture morphology was observed by scanning electron microscopy (SEM).It was indicated that the strong acoustic emission peak appeared at the valve specimen at a distance of 30 mm apart from the number 3 sensor.3Cr13 stainless steel valve sample fractured when the drawing time was 175.5 s,and the maximum acoustic emission amplitude was 84 dB.And the morphology of this sample showed a layered and sequential structure.When the deflection was 0.48 and 0.74,the ring count was 3.7×103 and 27.1×103,respectively.The fracture of 3Cr13 stainless steel valve sample had a large number of micro cracks in the test process,and it was the main reason for the signals.Cr element was the main composition in 3Cr13 stainless steel valve sample fracture,and its content was of 13.8 wt.%.