超超临界机组屏式过热器爆管原因  

Cause of tube explosion of platen superheater in ultra-supercritical unit

作　　者：蒙殿武 殷鹰 张学星 高大伟 MENG Dianwu;YIN Ying;ZHANG Xuexing;GAO Dawei(Jiangsu Datang Lüsigang Power Generation Co.,Ltd.,Nantong 226241,China;Datang Jiangsu Power Generation Co.,Ltd.,Nanjing 210008,China;China Datang Corporation Science and Technology Research Institute,Beijing 100040,China)

机构地区：[1]江苏大唐国际吕四港发电有限责任公司,南通226241 [2]大唐江苏发电有限公司,南京210008 [3]中国大唐集团科学技术研究总院有限公司,北京100040

出　　处：《理化检验（物理分册）》2023年第8期67-70,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：某超超临界机组屏式过热器发生爆管,采用宏观观察、化学成分分析、硬度测试、金相检验、扫描电镜和能谱分析等方法研究了爆管原因。结果表明:爆口附近组织发生老化,晶界析出大块或长条状σ相,越靠近爆口处,σ相数量越多,晶粒度也越大,且σ相周边存在孔洞和微裂纹,最终导致爆管。Tube burst occurred in platen superheater of an ultra-supercritical unit.The cause of tube burst was studied by means of macroscopic observation,chemical composition analysis,hardness test,metallographic examination,scanning electron microscope and energy spectrum analysis.The results show that the microstructure near the explosion port was aged,and the large or longσphase was precipitated at the grain boundary.The closer to the explosion port,the moreσphase,the larger the grain size,and there were holes and microcracks around theσphase,which eventually led to the tube explosion.

关 键 词：S30432钢 过热器 Σ相 超超临界机组 微裂纹 

分 类 号：TB31[一般工业技术—材料科学与工程] TG115.2[金属学及工艺—物理冶金]