锅炉水冷壁爆管原因分析

Cause analysis of boiler water wall burst

采用宏观检查、光谱分析、机械性能测试、金相分析等方法对某电厂#1锅炉前墙水冷壁爆管原因进行分析。宏观检查表明:爆口具有长期过热和短期过热的特征,向火侧表面存在密集的、相互平行的横向裂纹;金相检验表明:爆口附近向火侧的横向裂纹为热疲劳裂纹,破口由热疲劳裂纹发展而产生。建议尽快查找引起水冷壁管热疲劳的原因并对存在热疲劳裂纹的水冷壁管进行更换。

The author adopted macroscopic test,spectral analysis,mechanical property test,metallographic examination and other methods, and analyzed the cause reasons of a power plant's boiler water wall burst. Based on macroscopic test,we can find the trace of long- term and short-term overheat at the burst hole area. And there are intensive parallel transverse crack at the fire face. Based on metallographic examination,the transverse crack at fire face are thermal fatigue crack,the burst is caused by the aggravation of these thermal fatigue crack. The author suggested to find out what caused water wall thermal fatigue,and to replace those water wall pipe with thermal fatigue crack.