Corrosion Control and Monitoring.ppt

CorrosionControlandMonitoring ABCCompanyABCChemicalComplexEngineeringSpecification CorrosionControl Monitoring SCOPEThisEngineeringSpecificationincludesexternalandinternalcorrosioncontrolandmonitoringforDOTregulatedpipelines Design construction constructioninspection constructionacceptance operation andmaintenanceofDOTregulatedpipelinesarecoveredbythisEngineeringSpecification CorrosionControl Monitoring GENERALAllDOTregulatedABCpipelinesrequireprotectionfromtheenvironment Corrosiveelementsinthepipelinestreammustbeneutralizedorthepipematerialmustberesistanttothestream CorrosionControl Monitoring Minimumrequirementsforcorrosioncontrol ExternalCorrosionControlBuriedDOTregulatedpipelineswillbecoatedandcathodicallyprotectedInternalCorrosionControlKnowncorrosionratebasedonhistoricaldataCorrosionratefromanationalstandarddatabaseDatacollectedfromlaboratoryprototypetesting CorrosionControl Monitoring Minimumrequirementsforcorrosioncontrol Continued AboveGroundExternalCorrosionControlCoatwithanapprovedsystemwithresistancetothesoilandinternalfluidtemperature CorrosionControl Monitoring REFERENCESNACERP0169 92SurfacePreparation NACENo 1 SSPC SP5 WhiteMetalBlastCleaningNACENo 2 SSPC SP10 NearWhiteMetalBlastNACENo 3 SSPC SP6 CommercialBlastNACENo 4 SSPC SP7 Brush OffBlast CorrosionControl Monitoring PERSONNELREQUIREMENTSEngineeringdesignwillbeperformedbyaCorrosionEngineerwithtrainingandexperienceintheproposedcorrosioncontrolsystem Coating lining andpaintinginspectionwillbeperformedbyaninspectorwithappropriatetrainingandexperience CorrosionControl Monitoring PERSONNELREQUIREMENTS Cont Cathodicprotectioninstallationswillbeinspectedbyaninspectorwithtrainingandexperienceincathodicprotectioninspection Internalcorrosionmonitoringinstallationswillbeinspectedbyaninspectorwithtrainingandexperienceininternalcorrosionmonitoringinspection CorrosionControl Monitoring DESIGNREQUIREMENTS EXTERNALCathodicProtectionCriteriaBuriedOnshorePipelines Pipe to soilpotentialequaltoormorenegativethan 0 85voltsreferencedtocopper coppersulfateelectrodeandrecordedimmediatelyaftercurrentinterruption Instant offpotential OffshorePipelines Pipe to waterpotentialequaltoormorenegativethan 0 80voltsreferencedtoasilver silverchlorideelectrodewith instantoff potentialreading CorrosionControl Monitoring TankBottoms Steel to soilpotentialequaltoormorenegativethan 0 85voltswithacopper coppersulfatehalfcelland instantoff potential Maximumpipelinepotential Equaltoorlessthan 1 5voltstoastandardcopper coppersulfatehalfcellwiththecurrenttemporarilyinterrupted CorrosionControl Monitoring CoatingRequirementsNewburiedpipesectionsshallbecoatedwithoneofthefollowingtypes FusionbondedepoxyCoaltarepoxyPolyolefintapePrefabricatedfilmsOthercoatingsystemsapprovedbyCentralEngineeringSurfacepreparationshallbeinaccordancewithmanufacturer srecommendationandAppendixB CorrosionControl Monitoring MethodsUsedforCathodicProtectionGalvanicAnodeSystemsProvideprotectiontothestructurebythepotentialdifferencegeneratedbytheelectrochemicalreactionbetweenthestructureandtheanodethroughasoilorwaterelectrolyte Typicallyusedinsoilorwaterwithresistivitylessthan5000ohm cm CorrosionControl Monitoring MethodsUsedForCathodicProtection Cont ImpressedCurrentSystemsUsesexternalsourceofDCpower usuallyanACtrans formerwithanACtoDCrectifier toprovidethedrivingvoltagetothestructuretobeprotected Potentialdifferencebetweentheanodeandthestructurecreatescurrentflowfromtheanodeintothesoilandontothepipeline Usedwhenthesoilresistivityexceeds5000ohm cmand ormorethan5amperesofimpressedcurrentarerequired CorrosionControl Monitoring EquipmentGalvanicAnodeSystemsAnode Magnesiumonshore GalvalumIIIoffshore Junctionboxtoconnectleadsfromstructureandanode ImpressedCurrentSystemsDCtransformer rectifier suppliedasaunit Anode s withinertorlowreactivitycharacteristics Terminalboxwithresistorstoadjustcurrentflowtoeachanodeoranodestring CorrosionControl Monitoring MiscellaneousInstalllightningarrestors Provideelectricalisolation Insulatingflangesorspools Minimizeinterferencewithbondingstations Installteststationstomeasurepotentials Completethefollowingdocumentation Bondingand oranodebeddatasheet Bondingstationdatasheet Teststationdatasheet CorrosionControl Monitoring ImpactonOperatingEquipmentApplyNEMAelectrical classsafetyrequirementstoallequipmentassociatedwithimpressedcurrentinstallations InstallCPequipmentinareasnotrequiringintrinsicallysafedesign Locateanodebedstominimizeeffectonotherstructuresandtominimizemechanicaldamagefromforeignconstruction CorrosionControl Monitoring PerforminterferencetestingonallequipmentthatmaybedamagedbythenewCPinstallation Testingshallinclude butisnotlimitedto thefollowingsituations Pipelinescrossingwithin5feet MetalStructureswithin5feetofthepipeline MetalStructureswithin200feetoftheanodebed CorrosionControl Monitoring ImpactonOperatingEquipmentDesignCPsystemswithcapacityforcurrentlossthroughinterferencebondsandfuturecurrentlossduetocoatingdeterioration Minimizecasinginstallationsforprotectionofthecarrierpipe PerforminterferencetestingasshowninCompanyCorrosionControl MonitoringSpecificationAppendixE Providebondingstationsforeachcasinginstallation CorrosionControl Monitoring DESIGNREQUIREMENTS INTERNALCorrosivechemicalsinthepipelinestreamMayreducestream liquidorgas qualityorCausegeneralthinningorpittingattackShallbehandledbyoneofthefollowingmethods Neutralizationorremovalofthecorrosivechemicals Selectapipematerialwhichisresistant Coattheinternalsurfacesofthepipe CorrosionControl Monitoring Designpackagewillcontain Provisionsforupset emergencyconditions Recommendedcorrosionmonitoringprogram Recommendedcorrosionmonitoringequipment Installationofpersonnelsafetydevicesandplatformsrequiredforsafeperformanceofduties Piggingprocedurewhenpiggingfacilitiesareincludedinthedesignpackage Compliancewithregulationsoflocal state andfederaljurisdictionforpiggingprocedures CorrosionControl Monitoring DocumentationRequirementsDeterminethicknessmeasurementlocations TML s basedonthemostprobablelocationsforcorrosionorerosion corrosiondamage SelectTML swiththeassistanceoftheCorrosionEngineer Collectbaselinethicknessreadingsonallnewinstallations Installcorrosionmonitoringequipmentwherethe worstcase corrosionattackisexpected Providecorrosionmonitoringdatasheets CorrosionControl Monitoring DESIGNREQUIREMENTS ABOVEGROUNDEXTERNALCoatwithacoatingsystemthatisrecom mendedfortheenvironment Preparesurfaceinaccordancewithexternal coating systemmanufacturer srecommendations SeeCompanyCorrosionControl MonitoringSpecificationAppendixB CorrosionControl Monitoring INSTALLATIONQualityControl ExternalSystemsCoatingsQualifiedInspectorpresence 100 Fieldappliedcoatingsystems 100 inspection Shopappliedcoatingsystems 100 inspection Coatingrepairs 100 inspection Protectallstoredcoatingmaterialsattheconstructionsitefromweather particularlydirectlysunlightandheat CorrosionControl Monitoring PadinthepipetrenchInspectjustpriortolayingthepipeinthetrench Removealltrashandconstructiondebris CablesInspectuponreceiptatjobsitetodetectnicksanddamage 100 inspectionatthemillwithpropermillcert Avoiddamagingcableinsulationduringinstallation Splicecablesabovegroundinterminalboxes Usenon conductiveconduitsforcableinstallation Makecathodecableconnectionsaboveground ifpossible Repairburiedconnectioninaccordancewiththeoriginalcoatingmanufacturer srecommendations CorrosionControl Monitoring Transformer RectifierSystemsInstallbyaqualifiedelectrician TestrectifieratmaximumdesignloadtoassuretheDCoutputmeetsthemanufacturer sspecificationsincludingthemaximumACripple Calculaterectifierefficiencyandrecordontherectifierdatasheet Verifythepositivecableisattachedtotheanodebedandthenegativecableisattachedtotheprotectedstructureorpipe CorrosionControl Monitoring MiscellaneousConsiderationsInspectcablesinterminalboxestoassurecorrectlabels Verifyteststations bondingstations andassociatedhardwareforcathodicprotectionservice Contactowners operatorsofforeignpipelinestoenabletestingbeforeandafternewcathodicprotectionprojectcommissioning Recordbasereadingsonthenewpipelineorstructurepriortocathodicprotectionsystemenergizing Recordpotentialsatallinterferencebondsandteststations Energizesysteminsmallcurrentincrementsandrecordpotentialswitheachincreaseuntilprotectionisachieved Checkbondingstationsforinterferenceproblems Fileallcommissioningdataintheoriginalequipmentfile CorrosionControl Monitoring QualityControlRequirements InternalSurfaceInspectcorrosionmonitoringinstallationswiththeservicesofaqualifiedCorrosionTechnician Takebaselinedatapriortopipelinecommissioning Installlinedpipelinesperdesign Repairliningoffieldjointsasrecommended Installcorrosionmonitoringdevicesperdesign Completeelectricalinstallationswithqualifiedelectricians Documentcommissioninginformationasapartoftheoriginalequipmentfile CorrosionControl Monitoring