摘要
某200 MW汽轮机凝结泵泵轴在运行中发生断裂,对该轴断口进行宏观检测、金相检测、化学元素成分检测、力学性能检测和裂纹源区SEM扫描电镜及EDS能谱分析,其断口为典型的脆性断口,断裂方式为高周期疲劳断裂。该轴的热处理工艺与产品质量证明书要求不符,金相组织中存在的非金属夹杂物成为导致断裂的裂纹源,是发生疲劳断裂的主要原因。键槽位置设计不合理是发生断裂设计方面的原因。
A fracture accident occurred on the condensate pump shaft of a certain 200 MW turbine during normal operation. The macroscopic ,metallographic, composition of chemical elements ,mechanical properties ,SEM and EDS of the area of crack source were investigated.The fracture macroscopic is typical brittle fracture.Fracture mode is high cycle fatigue fracture.The main cause for the fracture failure is that the technology for heating processing has not conformed to the requirements of the quality certificate.Also, non-metallic inclusion is found on the crack source.The non-metallic inclusion generated crack source in the inner of shaft.Moreover,the designed position of the keyway has been found to be unreasonable,which lead to acceleration of the shaft fracture.
出处
《山东电力技术》
2015年第7期55-57,共3页
Shandong Electric Power
关键词
凝结水泵
断裂
疲劳
金相组织
condensate pump
fracture
fatigue
microstructure
