长期停备用锅炉水冷壁失效原因分析.pdf

经验交流

ExperienceExchange

长期停备用锅炉水冷壁

失效原因分析

于洋刘青华

（华电电力科学研究院有限公司，山东济南250003）

摘要：因利用小时数下降，某机组启停次数及停备用时间增加，在运行过程中水冷壁发生

脆性爆管，通过金相组织、垢量分析、垢成分分析等试验方法，对水冷壁管进行取样分析。结果

表明：机组长期停备用产生腐蚀，加之冷态启动期间水汽控制不良，造成水冷壁垢量偏大，；锅

炉运行期间，炉水在垢层下浓缩产生酸性环境，水冷壁管内壁发生垢下腐蚀，造成金属材质脱碳

产生CH，高压CH使水冷壁发生微裂纹，造成氢损伤，最终引起水冷壁失效爆管。

44

关键词长期停备用水冷壁氢损伤失效

中图分类号：TE-9文献标识码：ADOI：10.13726/j.cnki.11-2706/tq.2024.05.135.04

AnalysisoftheFailureCausesoftheWaterWall

ofthelong-termStandbyBoiler

YUYang,LIUQingHua

(HuadianElectricPowerResearchInstituteCo.,Ltd.Jinan250003,China)

Abstract:Duetothedecreaseinthenumberofutilizationhours,thenumberofstart-stoptimesand术技

thestopstandbytimeofaunitincrease,andbrittleburstsoccuronthewater-cooledwallduringoperation,

andthewater-cooledwallpipeissampledandanalyzedbymetallographicstructure,scalequantity

analysis,scalecompositionanalysisandothertestmethods.Theresultsshowthatthelong-termshutdown

oftheunitproducescorrosion,coupledwithpoorwatervaporcontrolduringcoldstart-up,resultingin

alargeamountofwaterwallscale.Duringtheoperationoftheboiler,thefurnacewaterisconcentrated

underthescalelayertoproduceanacidicenvironment,theinnerwallofthewater-cooledwallpipeis

corrodedunderthescale,resultinginthedecarburizationofmetalmaterialstoproduceCH4,andthehigh-

pressureCH4causesmicrocracksinthewater-cooledwall,causinghydrogendamage,andfinallycausing

thewater-cooledwalltofailandburstthepipe.

Keywords:stopstandby;water-coo