储罐底板点蚀三维形貌演化统计规律

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中图分类号：TE988 文献标志码：A

Abstract：Pitingcorosiononthebotomplatesofstorage tanksis theprimarycauseoffailure，andthethree-dimensional morphologyofpitsisthecrucialdataforcorosionevaluation.Existingstatisticalstudiesonpittngcorrosionmainlyfocuson one-dimensionalortwo-dimensionalparameters，suchasdepthandaspectratio，withoutfullyreflectingthe thre-dimensionalmorphologyofpits.Toelucidatetheevolutionofthethree-dimensionalmorphologyofpitingundertheoil-watersludgecoveringlayeronstoragetankbotomplates，corosion testsareconductedusingQ235steel.SurfacemorphologytestingmethodsandMATLABsoftwareareemployed tostatisticallyanalyzethemorphologyandevolutionofcorosionpitsonthe carbonstelsurface.Aclassficationmethodforpittypesbasedonmorphologyisproposed，andmathematicalrepresentations ofthethree-dimensionalmorphologyofdiferentpitcategoriesaredeveloped.Furthermore，theevolutionofpitmorphologyis characterizedusing typicalparametersfrommathematical functions.Corosionpitsarecategorizedintoparabolic，conical，bimodalandflat-botomed.Theresultsshowthatduringdiferentcorrosionstages，theshapesof thepitsaremainlyparabolic andconical.Parametersrepresenting horizontal dimensionsand surface inclinationofpits followalog-normaldistribution， with the logarithmic mean （μ） showing an inflection point at 6O days of corrosion.Pit depth parameters follow a Gaussian distribution，with the mean value （μ） exhibiting an exponential increase with corrosion time.

Keywords：tankbottomplate；oilsludgecoverlayer；classificationofcorrosiopitmorphology；pittingcorrosion；thee-dimensional morphological characterization；statistical analysis

储罐内底板长期浸泡在油泥水环境中，受服务环境、运行工况和操作变化的影响，储罐底板会产生一定的损伤，随服役时间的增长，部分损伤会逐渐累积，在各种腐蚀的共同作用下容易造成腐蚀开裂或点蚀穿孔，从而导致油品泄漏，造成重大损失。（剩余12093字）