某循环流化床锅炉高温过热器爆管原因分析  

Analysis of Tube Burst of High Temperature Superheater in a Circulating Fluidized Bed Boiler

作　　者：贺建平 高琨 李元翔 裴博文 袁晋雄 王德龙 王秀财 HE Jianping;GAO Kun;LI Yuanxiang;PEI Bowen;YUAN Jinxiong;WANG Delong;WANG Xiucai(State Energy Group Shanxi Electric Power Co.Ltd.,Taiyuan 030000,China;Shenhua Shendong Electric Power Shanxi Hequ Power Generation Co.Ltd.,Xinzhou 036500,China)

机构地区：[1]国家能源集团山西电力有限公司,山西太原030000 [2]神华神东电力山西河曲发电有限公司,山西忻州036500

出　　处：《工业加热》2023年第10期71-76,共6页Industrial Heating

摘　　要：某循环流化床锅炉高温过热器出现了爆管的现象,爆口附近其他受热面也被吹损。通过宏观检查、化学成分分析、金相检验、力学性能试验、断口分析及能谱分析等方法,对发生爆漏的高过鳍片管样品进行了失效原因的分析,结果表明:样品的角焊缝外观质量有缺陷,焊缝的边缘圆滑过渡不佳,局部存在凹陷,角焊缝其他检验结果及换热管母材与鳍片母材的其它检验结果未见明显异常;样品的爆管类型为应力腐蚀,主要是管屏在运行过程中由于不同位置温度差异大,由于热胀不同产生了应力,此外,角焊缝残留了部分焊接应力。角焊缝外观成形缺陷也加速了爆管的发生。建议对该循环流化床锅炉的高过管屏角焊缝部位进行探伤,若发现焊接缺陷,应及时消除。同时,应采取降低管屏热胀应力的措施,如可将管屏沿中部鳍片纵向切开等。研究结果可为国内其他锅炉同类问题解决提供参考。The high⁃temperature superheater of a circulating fluidized bed boiler has a tube burst phenomenon,other heating surfaces near the blast were also damaged.By means of macroscopic inspection,chemical composition analysis,metallographic inspection,mechanical property test,fracture analysis and energy spectrum analysis,the failure causes of the high⁃over⁃fin tube samples were analyzed,and the results showed that:the appearance quality of the fillet weld of the sample is not good,there are poor smooth transition of the weld edge and small pits.Other inspection results of fillet weld and various inspection results of the tube base metal and the fin base metal meet the standard requirements or no obvious abnormalities are found.The type of tube bursting of the sample is stress corrosion,and the stress factor mainly comes from the thermal expansion stress caused by uneven heating of the whole tube screen during operation and the welding residual stress of fillet weld.Poor appearance of fillet weld accelerates the tube bursting.It is suggested to inspect the fillet weld of the circulating fluidized bed boiler,and if the welding defect is found,it should be eliminated in time.At the same time,measures should be taken to reduce the thermal expansion stress of the tube screen,such as the tube screen can be cut lengthwise along the middle fin.The results can provide reference for similar faults of other boilers in China.

关 键 词：循环流化床锅炉 高温过热器 爆管 受热不均 热胀应力 

分 类 号：TF578.31[冶金工程—钢铁冶金]