摘要
某电厂锅炉在运行状态下发生水冷壁爆管事故,采用宏观观察、力学性能测试、化学成分分析、金相检验、扫描电镜及能谱分析等方法对爆管原因进行分析。结果表明:水冷壁密封板根部存在未熔合缺陷,在该缺陷处容易形成应力集中;在锅炉启停或载荷频繁波动造成的疲劳应力,以及密封板与水冷壁管间温差热应力的综合作用下,水冷壁管形成疲劳裂纹,裂纹逐渐向管内壁扩展,最终穿透管壁,导致水冷壁管发生泄漏事故。
A water wall tube explosion accident occurred in a power plant boiler during operation.The causes of tube explosion were analyzed by means of macroscopic observation,mechanical property test,chemical composition analysis,metallographic examination,scanning electron microscope and energy spectrum analysis.The results show that there was an incomplete fusion defect at the root of the seal plate of the water wall,and stress concentration was easy to form at the defect.Under the combined action of fatigue stress caused by boiler start-stop or frequent load fluctuation and thermal stress caused by temperature difference between sealing plate and water wall tube,fatigue cracks were formed in water wall tube.The cracks gradually expanded to the inner wall of the tube,and finally penetrated the tube wall,resulting in leakage accident of water wall tube.
作者
张炜
许龙发
张志达
ZHANG Wei;XU Longfa;ZHANG Zhida(Guangzhou Special Equipment Inpection and Research Institute,Guangzhou 510663,China)
出处
《理化检验（物理分册）》
CAS
2024年第12期58-62,共5页
Physical Testing and Chemical Analysis(Part A:Physical Testing)
基金
广州市市场监管局科技项目(2024KJ20)。
关键词
水冷壁管
焊接缺陷
疲劳裂纹
热应力
载荷
water wall tube
welding defect
fatigue crack
thermal stress
load
作者简介
张炜(1987-),男,硕士,工程师,主要从事金属材料的失效分析、特种设备安全研究工作,weizhang368@163.com。
