622MW亚临界W火焰锅炉高温过热器管漏原因分析

Tube Leakage Cause Analysis of High Temperature Superheater in 622MW Subcritical W Flame Boiler

为了分析622MW亚临界W火焰锅炉高温过热器管的泄漏原因,对其进行了宏观形貌、力学性能、化学成分和显微组织检测。结果表明,高温过热器管材化学成分达到标准要求,屈服强度、拉伸强度及硬度合格,管壁环向裂纹为初始泄漏源,其产生原因为加工缺陷。在毁损管屏经维修更换后,机组顺利完成了试运行。

In order to analyze the leakage reason for 622MW subcritical W flame boiler high temperature superheater pipe, the macro-morphology, mechanical properties testing, chemical composition and microstructure of the pipe were tested. The results show that the chemical composition of high temperature superheater pipe meets the standard requirements, the yield strength, tensile strength and hardness are qualified, the circumferential cracks in pipe wall are the initial leakage source, and the reason is the processing defects. After the repair and replacement of damaged tube, test run of unit was successfully completed.