某660MW超临界锅炉高温再热器爆管分析  

Analysis of Tube Burst in High Temperature Reheater of 660 MW Supercritical Boiler

作　　者：秦晓佳 梁皓 程海飞[3,4] 方振邦 秦孜 QIN Xiaojia;LIANG Hao;CHENG Haifei;FANG Zhenbang;QIN Zi(Training Center of State Grid Anhui Electric Power Co.,Ltd.,Hefei 230022,China;Anhui Electrical Engineering Professional Technique College,Hefei 230051,China;State Grid Anhui Electric Power Co.,Ltd.Electric Power Research Institute,Hefei 230601,China;Anhui Wanxin Human Resources Management Co.,Ltd.,Hefei 230061,China;State Grid Anhui Ultra High Voltage Company,Hefei 230000,China)

机构地区：[1]国网安徽省电力有限公司培训中心,安徽合肥230022 [2]安徽电气工程职业技术学院,安徽合肥230051 [3]国网安徽省电力有限公司电力科学研究院,安徽合肥230601 [4]安徽皖信人力资源管理有限公司,安徽合肥230061 [5]国网安徽省电力有限公司超高压分公司,安徽合肥230000

出　　处：《安徽电气工程职业技术学院学报》2022年第3期72-75,共4页Journal of Anhui Electrical Engineering Professional Technique College

摘　　要：某电厂660 MW机组锅炉高温再热器投运8个月后发生爆管泄漏事故,爆管位置为高温再热器12Cr1MoVG钢焊接接头。文章通过宏观检查、化学成分分析、金相检验和力学性能检测等手段分析此次爆管的原因,结果表明此次爆管开裂位于焊接接头的熔合区,该位置硬度超标,短期高温运行后,熔合组织中存在魏氏组织、且碳化物大量析出长大,造成焊缝熔合区再热脆化,在拘束应力作用下,熔合区产生再热裂纹,最终导致开裂。Eight months after the high temperature reheater of a 660 MW supercritical boiler was put into operation, a pipe burst leakage accident occurred. The tube burst was located at the 12 Cr1 MoVG steel welded joint of the high temperature reheater. In this paper, the causes the tube burst are analyzed by means of macro inspection, chemical composition analysis, metallographic inspection and mechanical property testing. The results show that the tube burst is located in the fusion zone of the welded joint, where the hardness exceeds the standard. There is Widmandelsteiner structure in the fusion structure, and a large number of carbides precipitate and grow, which causes the reheat embrittlement of the fusion zone of the weld. Under the action of restraint stress, the fusion zone produces reheat cracks, which eventually lead to cracking.

关 键 词：660MW超临界机组 爆管 12CR1MOVG 焊接接头 

分 类 号：TM621.2[电气工程—电力系统及自动化]