某电厂水冷壁管泄漏原因分析  

Cause Analysis on Leakage of Water Wall Tube in a Power Plant

作　　者：王建国[1] 王智春[1] 韩哲文[1] 杨鑫莹 宋子博 WANG Jianguo;WANG Zhichun;HAN Zhewen;YANG Xinying;SONG Zibo(North China Electric Power Research Institute Co.,Ltd.,Beijing 100045,China)

机构地区：[1]华北电力科学研究院有限责任公司,北京100045

出　　处：《理化检验（物理分册）》2020年第6期63-65,共3页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：某电厂超临界锅炉水冷壁管在运行过程中发生泄漏。通过宏观观察、化学成分分析、金相检验、力学性能试验、扫描电镜及能谱分析等方法对管子的泄漏原因进行了分析。结果表明:水冷壁管对接焊缝中存在结晶裂纹,该结晶裂纹在管内压应力和焊接残余应力的作用下不断扩展,形成穿透管壁的横向裂纹,最终导致水冷壁管泄漏。The water wall tube of supercritical boiler in a power plant leaked during operation.The causes of tube leakage were analyzed by means of macroscopic observation,chemical composition analysis,metallographic examination,mechanical property test,scanning electron microscope and energy spectrum analysis.The results show that there were solidification cracks in the butt weld of water wall tube.Under the action of internal pressure stress and welding residual stress,the solidification cracks propagated continuously,formed transverse cracks through the tube wall,and finally led to the water wall tube leakage.

关 键 词：水冷壁管 对接焊缝 泄漏 结晶裂纹 残余应力 

分 类 号：TG115.2[金属学及工艺—物理冶金]