低氮改造后的中心回燃式锅炉前管板管端裂纹原因分析  

Cause Analysis of Tube End Crack in the Front Tube Plate of Central Reverse Flame Boiler after Low NO,Emission Retrofit

作　　者：胥杨[1] 陈乐[1] XU Yang;CHEN Le(Shanghai Institute of Special Equipment Inspection and Technical Research,Shanghai 200062,China)

机构地区：[1]上海市特种设备监督检验技术研究院,上海200062

出　　处：《锅炉技术》2021年第S01期67-71,共5页Boiler Technology

摘　　要：为了打赢蓝天保卫战,上海市的中小燃气锅炉于2020年底完成了低氮改造任务。某单位低氮改造后的中心回燃式锅炉,检验后发现锅炉前管板和烟管存在多条裂纹,导致泄漏,存在严重的安全隐患。对发生问题的部位取样进行失效分析,分析其可能的产生原因,探讨对策积极防范此类事故的发生。经失效分析可推断,开裂为烟管与前管板焊缝根部起始的疲劳扩展开裂。因此,中心回燃式锅炉不宜采用直接更换低氮燃烧器的方式以达到低氮燃烧的效果。In order to winning the battle against air pollution,low NO_(x) emission retrofit of small and medium gas boiler of shanghai had been completed in the end of 2020.A lot of cracks were found in the front plate and fire-tube of boilers,though the inspection of Low NO_(x) emission retrofit of central reverse flame boiler,which might lead to leakage and serious safety hazard.The purpose of this article is to conduct a failure analysis on the sample of the problem portion,analyze the possible causes,discuss countermeasures to actively prevent the occurrence of such accidents.According to the failure analysis,it can be concluded that the crack is the fatigue propagation crack starting from the root of welding seam between fire-tube and the front plate.Therefore,in order to achieve the effect of low nitrogen burner,it is not suitable to directly replace the low nitrogen burner for central reverse flame boiler.

关 键 词：低氮改造 中心回燃式 裂纹 原因分析 

分 类 号：TK229.6[动力工程及工程热物理—动力机械及工程]