锅炉水冷壁管爆裂泄漏原因  

Reason of boiler water wall tube bursting and leakage

作　　者：龚光平 马源旺 张凯 张凯博 陈晨 GONG Guangping;MA Yuanwang;ZHANG Kai;ZHANG Kaibo;CHEN Chen(Guangdong Institute of Special Equipment Inspection and Research Shunde Branch,Foshan 510663,China)

机构地区：[1]广东省特种设备检测研究院顺德检测院,佛山510663

出　　处：《理化检验(物理分册)》2025年第3期59-61,76,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

基　　金：广东省特检院科技项目(2021CY-1-06)。

摘　　要：针对某电厂水冷壁管发生爆裂事故,采用宏观观察、力学性能测试、金相检验、扫描电镜及能谱分析等方法分析其爆裂原因。结果表明:水冷壁弯管处密封板角焊缝结构突变引起应力集中,在角接接头根部热影响区形成裂纹;在结构温差应力、机组启停、负荷波动、疲劳应力等的综合作用下,裂纹由管外壁向内壁扩展,并最终贯穿管壁,导致水冷壁管发生爆裂泄漏事故。Aiming at the burst accident of water wall tube in a power plant,the causes of burst were analyzed by means of macroscopic observation,mechanical property test,metallographic examination,scanning electron microscope and energy spectrum analysis.The results show that the sudden change of the fillet weld structure of the sealing plate at the elbow of the water wall caused stress concentration,and cracks were formed in the heat affected zone at the root of the fillet joint.Under the combined action of structural temperature difference stress,unit start-stop,load fluctuation and fatigue stress,the crack propagated from the outer wall of the tube to the inner wall,and finally penetrated the tube wall,resulting in a burst leakage accident of the water wall tube.

关 键 词：水冷壁管 角焊缝 应力集中 热疲劳 

分 类 号：TG115.2[金属学及工艺—物理冶金] TB31[金属学及工艺—金属学]