锅炉给水加氧对奥氏体管汽侧氧化皮形成及剥落的影响  

Influence of the oxygenated treatment of boiler feedwater on forming and shedding of oxide skin in steam side of austenitic pipe

作　　者：蔡晖[1] 熊伟[2] 唐丽英[1] 殷尊[1] 

机构地区：[1]西安热工研究院有限公司,西安710032 [2]华能玉环电厂,浙江玉环317600

出　　处：《华电技术》2015年第5期14-20,共7页HUADIAN TECHNOLOGY

基　　金：华能660 MW高效超超临界机组应用技术研究(TN-14-HNK01)

摘　　要：对某电厂末级过热器和再热器锅炉管在不同加氧方式下不同时间段的管样进行了管材显微组织分析、晶粒度测量、内壁氧化层金相分析、典型内壁氧化层结构的扫描式电子显微镜(SEM)和X射线能谱仪(EDS)分析。结果表明:给水加氧促进了管子内壁氧化层外层Fe2O3的形成;其中1台锅炉的末级再热器管样氧化程度最严重,内壁无细晶带的管样比例偏高;内壁未能形成均匀连续的富Cr层是其较早发生氧化皮集中剥落的主要原因之一,给水加氧是氧化层脱落的促进因素。The pipes of the finishing superheater and the reheater of the boiler of a power plant were investigated experimentally.The pipe samples were obtained in different time periods under different oxygenation treatment modes. The experimental methods includes the microstructure analysis,the grain size measurement,the inner wall oxide layer metallographic analysis and the scanning electron microscope( SEM) analysis and X-ray energy dispersive spectrometer( EDS) analysis for typical inner wall oxide layer structure. The results show that the feedwater oxygenatin treatment can acilitate forming of Fe2O3 outer shell of oxyde layer in pipe inner wall. The sample tubes of the final-stage reheater of a boiler were oxygenated most seriously,the percentage of the sample tubes,in which there was not the fine grain zone in inner wall,is larger. In the inner wall of the sample tubes,the uniform and continous Cr-rich layer did not formed,and this is one of the main reasons caused the oxide skin to shed concentratedly. The feedwater oxygenation treatment is a factor to promote the oxyde skin to shed.

关 键 词：锅炉 加氧 内壁氧化层 富 CR 层 剥落 

分 类 号：TM621.2[电气工程—电力系统及自动化]