某电厂锅炉后屏过热器管泄漏原因分析

Analysis on leakage of rear plate superheater tubes of boiler in a power plant

通过对某电厂锅炉后屏过热器爆管管壁进行宏观检验、显微组织分析及内壁氧化皮测厚,并结合其生成机制判断锅炉后屏过热器爆管与长期超温及管壁减薄有关。根据后屏过热器检查状况,提出了保障其长期安全运行的措施。

A tube crack accident of the boiler rear plate superheater in a power plant occurred. The macroscopic examination,the microstructure analysis and the thickness measurement of the oxide skin on internal wall were down for the cracked tube.Combining with the formation mechanism of the oxide skin,it was determined that the tube crack accident of the rear plate superheater is caused by overtemperature at long time and decreasing of the tube wall thickness. Based on the examination results of the rear plate superheater,the measures to ensure safe operation at long term were proposed.