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AvoidingPressureSurgeDamageinPipelineSystemsPresentedbyGeoffreyDStoneCPEngFIEAustAvoidingPressureSurgeDamage1FirstlyQuantifytheProblem“Inphysicalsciencethefirstessentialstepinthedirectionoflearninganysubjectistofindprinciplesofnumericalreckoningandpracticablemethodsformeasuringsomequalityconnectedwithit.Ioftensaythatwhenyoucanmeasurewhatyouarespeakingabout,andexpressitinnumbers,youknowsomethingaboutit;butwhenyoucannotmeasureit,whenyoucannotexpressitinnumbers,yourknowledgeisofameagreandunsatisfactorykind;itmaybethebeginningofknowledge,butyouhavescarcelyinyourthoughtsadvancedtothestateofScience,whateverthemattermaybe."LordKelvin[PLA,1883-05-03]FirstlyQuantifytheProblem“I2Australian&InternationalCodes&StandardsPressureVesselCodeAS1210ArcWeldedSteelPipeAS1579SubmarinePipelineCodeAS1958InstallationofUPVCAS2032InstallationofPE AS2033BuriedFlexiblePipelinesDesignAS2566Gas&LiquidPipelineCode AS2885GRPPipesforWater&SewerageAS3571InstallationofABSPipesAS3690PressurePipingCodeAS4041WSA01PolyethylenePipelineCodeWSA02SewerageCodeofAustraliaWSA03WaterSupplyCodeWSA04SewagePumpingStationsPIPA-OP010A:Part1PolyethylenePressurePipesDesignforDynamicStressesPowerPipingASMEB31.1ProcessPipingASMEB31.3PipelineTransportationSystemsforHydrocarbonsandotherLiquidsASMEB31.4RefrigerationandHeatTransferComponentsASMEB31.5BuildingServicesPipingASMEB31.9SlurryTransportationPipingSystems ASMEB31.11Glass-reinforcedplastics(GRP)pipingISO14692-3Design&ConstructionofGRPPipesBS7159AWWAFibreglassPipe ANSI/AWWAC950Australian&InternationalCod3Therearetwocategoriesofdamagethatarisefromsurgeeventscatastrophicfailureofthepipelinesystemorequipmentfatiguefailureofthepipeline,supports,instrumentation,equipmentandcomponentsTherearetwocategoriesofda4EquipmentandProcessesSolutionsStrongerpipeworktowithstandthepressuresurgeReroutingpipingChangeofpipematerialtoonewithalowermodulus(i.e.thermoplasticpipematerials)FlowcontrolvalvesAir/VacuumReleasevalvesIntermediatecheckvalvesNonslamcheckvalvesBypassValvesGasaccumulatorsLiquidaccumulatorsSurgetanksSurgeshaftsSurgeanticipationvalvesReliefvalvesBurstingdiscsWeakpipesectionsIncreasediameterofpipelinetoreduceaveragevelocityVariablespeeddrivesSoftstartersValveclosureandopeningtimesIncreasingtheinertiaofpumpsandmotors(i.e.flywheelsorbyselection)MinimisingresonancehazardsandincreasereliabilitybyadditionalsupportsInvestmentinmoreengineeringEquipmentandProcessesSoluti5SelectionProcessSelectionProcess6PipingDesignUsingStrongerPipeorRe-RoutingthePipelineUseofStrongerPipeworkIncreaseincapitalcostsforpipe,fittings,valvesandinstrumentsIncreaseinvelocityandcelerityaswallthicknessincreasesIncreaselikelihoodoffatiguedamageandmaintenancecostsifsurgeeventsfrequentPipeinherentlymaintenancefreecomparedtoothersurgedevicesNeedstobedeterminedatdesignstageRe-RoutingPipelineIncreaseincapitalcostsLandoreasementacquisitionDirectiondrillingIncreasedlengthofpipelineHydraulicgradelineabovethepipelineprofilereducespotentialforcavitationPossibleincreaseinenergyInherentlymaintenancefreeNeedstobedeterminedatdesignstagePipingDesignUsingStrongerP7ChangeofPipeMaterialtoOnewithaLowerModulus(i.e.thermoplasticpipematerials)

CapitalcostneutralNotauniversalsolutionbecauseoflimitedpressureclassesavailableThermoplasticpipematerialspropertiesvarywithtemperature,strainrateandtimeDoesnotprotectwhencolumnseparationoccursWallthicknessselectiontoallowforvacuumconditionsLocalbucklingatabovegroundsupportstobedesignedNeedstobedeterminedatdesignstageChangeofPipeMaterialtoOne8FlowControlValvesModeratecapitalcostIncreasedmaintenancetoensuretheyremaineffectiveCanbeusedformultipledutiesandscenariosPowerorinstrumentationnotnecessarilyrequiredCanberetrofittedFlowControlValvesModerateca9Air/VacuumReleaseValvesIncreasedcapitalcostsIncreasedmaintenancetoensureeffectiveoperationUserequiresextensivemodellingtoensureoperationinallscenariosNotsuitableforhazardousliquidsPrimarydutyisforlinefillinganddrainingandhencelocationmaynotbeoptimalforsurgemitigationNotallairvalvesaresuitableforthispurposeduetotheiroriginaldesignValvepitmaybeinroadcausingproblemsduringconstructionormaintenanceCanberetrofittedeasilyifreducingteesinpipelinealreadyinstalledotherwiseteetypecouplingsrequiredtobefittedAir/VacuumReleaseValvesIncre10ModernDesignofAir/VacuumReleaseValve-VentomatModernDesignofAir/Vacuum11IntermediateCheckValves

IncreaseincapitalcostsforcheckvalvebutreductioninratingofotherpipelinecomponentsEffectiveinsplittingthesurgepressureriseintwoDegreeofincreaseinmaintenanceminimalProtectspumpsfromhighestpeakpressureNonslamcheckvalvespreferredValvepitmaybeinroadwaycausingtrafficproblemsduringconstructionormaintenanceCheckvalvesarenotconsideredanadequateformofisolationandhenceshouldbeinstalledwithisolationvalvesNeedstobedeterminedatdesignstageotherwisepipelineneedstobeoutofserviceforretrofittingcheckvalveIntermediateCheckValves

Incr12NonSlamCheckValveCapitalcostincreaseFastclosingvalvereducessurgepressureatpumpReducesfatiguedamageIncreaseinmaintenancelowInherentlytroublefreeAvailableasshortorlongpatternUsedextensivelyinEuropeCanberetrofittedasvalvesstandardlengthsNonSlamCheckValveCapitalco13ComparisonofCheckValvePerformanceComparisonofCheckValvePerf14NorevaAnnulusTypeNonSlamCheckValvesNorevaAnnulusTypeNonSlamC15BypassCheckValvesIncreasecapitalcostIncreasemaintenancetoensureeffectiveoperationNeedspositivepressureupstreamtoprovideenergytofillcavitationvoidsSimpleandeffectiveforovercomingnegativepressuresDoesnotprovideprotectionforpositivepressuresCanbereadilyretrofittedBypassCheckValvesIncreaseca16BladderTypeGasAccumulatorIncreasedcapitolcostsMaintenancelevellowforbladdertypeProvidessecureprotectionforpositiveandnegativesurgepressuresBestlocatedatsourceofpressuretransienteventOverseasdesignandmanufactureCanberetrofittedLongleadtimeBladderTypeGasAccumulatorIn17Hydro-PneumaticAccumulatorIncreasedcapitalcostsMaintenancelevelhighforhydropneumatictypeBestlocatedatsourceofpressuretransienteventProvidessecureprotectionforpositiveandnegativesurgepressuresLocaldesignandmanufactureCanberetrofittedifbranchedteesfittedtopipeworkLongleadtimeHydro-PneumaticAccumulatorInc18Liquidaccumulators

IncreasecapitalcostDifficulttomodelwithouttestdataInherentlymaintenancefreeCanberetrofittedbutgenerallyalongleadtimeLiquidaccumulators

Increasec19SurgeTanks

andSurgeShaftsCommonlyusedinwatertransmissionsystemsProvidesprotectionfromnegativepressureeventsbutNOTforpositivepressuresInherentlymaintenancefreeexceptforrefillingfacilityofsurgetankTelemetryrequiredformonitoringCanberetrofittedbutgenerallyalongleadtimerequiredSurgeTanks

andSurgeShaftsCo20SurgeAnticipationValvesModeratecapitalcostComplexdevicesRequirepowerintheformofelectric,hydraulicorpneumatictooperateDonotcoverallsurgeeventsinapipelinesystemsHighmaintenancetoensurethattheyworkwhenneededVendorswhoperformsurgeanalysisandrecommendationareNOTnecessarilydesignengineersanddoNOTtakeresponsibility.Oftendonothavelatest,orhavelimitedcapability,software.CanberetrofittedhowevermoderateleadtimesSurgeAnticipationValvesModer21ReliefValves

andBurstingDiscsIncreaseincapitalcostConventionaldevicesdonotreactquicklyenoughtopreventdamagefromsurgepressureDonotprotectagainstvacuumconditionsHighlevelofmaintenanceBurstingdiscsrequirereplacementafteroperationNeedforregistrationandroutinetestingperCodeSuitableforlethalandflammableliquidsaspartofanoverallprotectionstrategyCanberetrofittedhowevermaybemoderateleadtimesReliefValves

andBurstingDis22WeakPipeSectionsCapitalcostneutralReducescelerityinsensitivesectionsReducedsurgepressuremagnitudeReducedfatiguedamageCouldbedamagedbyvacuumconditionsSuitableforlowpressuresystemsinthewaterindustryInherentlymaintenancefreeNotauniversalsolutionNeedstobedeterminedatdesignstageWeakPipeSectionsCapitalcost23IncreaseDiameterofPipelinetoReduceAverageVelocity

ReducedcelerityandsurgepressureIncreaseincapitalcostofpipe,excavation,valvesandinstrumentsIncreasedlifeoftheassetFutureaugmentationpossibleInherentlymaintenancefreeReductioninenergyofpumpingSettlingofsolidsmorelikelyNeedstobedeterminedatdesignstageIncreaseDiameterofPipeline24VariableSpeedDrives

andSoftStarters

IncreaseincapitalcostsandcomplexityLowlevelofmaintenanceIncreasedfrequencyofreplacementandupgradeProvidesNOprotectionforlossofpowerscenariosSoftstartersprotectpowersupplymorethanpipeline;thereareNOguaranteestheycanbesettolimitsurgepressuresReducedfatigueissuesfornormalstop/startLargerswitchroomrequiredtohousedevicesNeedstobedeterminedatdesignstageascostlytoretrofitandtohouseinaswitchroomVariableSpeedDrives

andSoft25ValveClosureandOpeningTimes

LowcapitalcostsolutionCanbeeffectiveinreducingsurgepressuresRequirespowersupplyintheformofhydraulic,pneumaticorelectricalenergytobetotallyreliableNeedsuninterruptiblepowersupplyforsecureoperationRequiresextensivemodellingtocoveralloperationalscenariosRequiresroutinetestingtobeeffectiveCanbemodifiedduringcommissioningoroperationifvalvesareautomatedandfittedwithadjustableopening/closingdevicesValveClosureandOpeningTime26IncreasingtheInertiaofPumpsandMotorsModestincreaseincapitalcostFlywheelsincreasemomentofinertiaFourpolespeedmotorsandpumpshavelargermomentofinertiaandhaveotherbenefitsovertwopolemotordrivenpumpsPhysicallylargerpumpsetsandhencebuildingsmaybeincreasedinsizeInherentlyalowmaintenancesolutionNeedstobedeterminedatdesignstageIncreasingtheInertiaofPump27MinimisingResonanceHazardsandIncreaseStiffnessbyAdditionalSupportsMinimiseResonanceIncreasedcapitalcostsIncreasedengineeringtodeterminedynamicbehaviourofpipingReducesdamagearisingfromdynamicloadingandvibrationCanberetrofittedquicklyImprovedStiffnessIncreaseincapitalcostsReductioninpeakpressureduetoreducedcelerityAcceptanceofhighfatiguedamagecausingincreaseinmaintenancecostsMoresecurepipingsystemInherentlymaintenancefreeCanbereadilyretrofittedMinimisingResonanceHazardsa28InvestmentinMoreEngineeringadollarspentatconceptstageisworthtendollarsatdesignstageonehundreddollarsatprocurementstageonethousanddollarsatfabricationstagetenthousanddollarsduringconstructionandonehundredthousanddollarsduringcommissioningonemilliondollarsoncethelawyersareinvolved!!!!!!!!!!

“Therealwaysappearstobeenoughmoneytoinvestigateafailurebutneverenoughtodothedesignengineeringinthefirstplace”TheEngineersLamentInvestmentinMoreEngineering29ButjustawordfromLordKelvintotemperthequestforananswer:

“Largeincreasesincostwithquestionableincreasesinperformancecanbetoleratedonlyinracehorsesandfancywomen.“Thereforeyourinvestmentshouldbeinengineeringoooooo-TheEnd-ooooooButjustawordfromLordKelv30謝謝謝謝31AvoidingPressureSurgeDamageinPipelineSystemsPresentedbyGeoffreyDStoneCPEngFIEAustAvoidingPressureSurgeDamage32FirstlyQuantifytheProblem“Inphysicalsciencethefirstessentialstepinthedirectionoflearninganysubjectistofindprinciplesofnumericalreckoningandpracticablemethodsformeasuringsomequalityconnectedwithit.Ioftensaythatwhenyoucanmeasurewhatyouarespeakingabout,andexpressitinnumbers,youknowsomethingaboutit;butwhenyoucannotmeasureit,whenyoucannotexpressitinnumbers,yourknowledgeisofameagreandunsatisfactorykind;itmaybethebeginningofknowledge,butyouhavescarcelyinyourthoughtsadvancedtothestateofScience,whateverthemattermaybe."LordKelvin[PLA,1883-05-03]FirstlyQuantifytheProblem“I33Australian&InternationalCodes&StandardsPressureVesselCodeAS1210ArcWeldedSteelPipeAS1579SubmarinePipelineCodeAS1958InstallationofUPVCAS2032InstallationofPE AS2033BuriedFlexiblePipelinesDesignAS2566Gas&LiquidPipelineCode AS2885GRPPipesforWater&SewerageAS3571InstallationofABSPipesAS3690PressurePipingCodeAS4041WSA01PolyethylenePipelineCodeWSA02SewerageCodeofAustraliaWSA03WaterSupplyCodeWSA04SewagePumpingStationsPIPA-OP010A:Part1PolyethylenePressurePipesDesignforDynamicStressesPowerPipingASMEB31.1ProcessPipingASMEB31.3PipelineTransportationSystemsforHydrocarbonsandotherLiquidsASMEB31.4RefrigerationandHeatTransferComponentsASMEB31.5BuildingServicesPipingASMEB31.9SlurryTransportationPipingSystems ASMEB31.11Glass-reinforcedplastics(GRP)pipingISO14692-3Design&ConstructionofGRPPipesBS7159AWWAFibreglassPipe ANSI/AWWAC950Australian&InternationalCod34Therearetwocategoriesofdamagethatarisefromsurgeeventscatastrophicfailureofthepipelinesystemorequipmentfatiguefailureofthepipeline,supports,instrumentation,equipmentandcomponentsTherearetwocategoriesofda35EquipmentandProcessesSolutionsStrongerpipeworktowithstandthepressuresurgeReroutingpipingChangeofpipematerialtoonewithalowermodulus(i.e.thermoplasticpipematerials)FlowcontrolvalvesAir/VacuumReleasevalvesIntermediatecheckvalvesNonslamcheckvalvesBypassValvesGasaccumulatorsLiquidaccumulatorsSurgetanksSurgeshaftsSurgeanticipationvalvesReliefvalvesBurstingdiscsWeakpipesectionsIncreasediameterofpipelinetoreduceaveragevelocityVariablespeeddrivesSoftstartersValveclosureandopeningtimesIncreasingtheinertiaofpumpsandmotors(i.e.flywheelsorbyselection)MinimisingresonancehazardsandincreasereliabilitybyadditionalsupportsInvestmentinmoreengineeringEquipmentandProcessesSoluti36SelectionProcessSelectionProcess37PipingDesignUsingStrongerPipeorRe-RoutingthePipelineUseofStrongerPipeworkIncreaseincapitalcostsforpipe,fittings,valvesandinstrumentsIncreaseinvelocityandcelerityaswallthicknessincreasesIncreaselikelihoodoffatiguedamageandmaintenancecostsifsurgeeventsfrequentPipeinherentlymaintenancefreecomparedtoothersurgedevicesNeedstobedeterminedatdesignstageRe-RoutingPipelineIncreaseincapitalcostsLandoreasementacquisitionDirectiondrillingIncreasedlengthofpipelineHydraulicgradelineabovethepipelineprofilereducespotentialforcavitationPossibleincreaseinenergyInherentlymaintenancefreeNeedstobedeterminedatdesignstagePipingDesignUsingStrongerP38ChangeofPipeMaterialtoOnewithaLowerModulus(i.e.thermoplasticpipematerials)

CapitalcostneutralNotauniversalsolutionbecauseoflimitedpressureclassesavailableThermoplasticpipematerialspropertiesvarywithtemperature,strainrateandtimeDoesnotprotectwhencolumnseparationoccursWallthicknessselectiontoallowforvacuumconditionsLocalbucklingatabovegroundsupportstobedesignedNeedstobedeterminedatdesignstageChangeofPipeMaterialtoOne39FlowControlValvesModeratecapitalcostIncreasedmaintenancetoensuretheyremaineffectiveCanbeusedformultipledutiesandscenariosPowerorinstrumentationnotnecessarilyrequiredCanberetrofittedFlowControlValvesModerateca40Air/VacuumReleaseValvesIncreasedcapitalcostsIncreasedmaintenancetoensureeffectiveoperationUserequiresextensivemodellingtoensureoperationinallscenariosNotsuitableforhazardousliquidsPrimarydutyisforlinefillinganddrainingandhencelocationmaynotbeoptimalforsurgemitigationNotallairvalvesaresuitableforthispurposeduetotheiroriginaldesignValvepitmaybeinroadcausingproblemsduringconstructionormaintenanceCanberetrofittedeasilyifreducingteesinpipelinealreadyinstalledotherwiseteetypecouplingsrequiredtobefittedAir/VacuumReleaseValvesIncre41ModernDesignofAir/VacuumReleaseValve-VentomatModernDesignofAir/Vacuum42IntermediateCheckValves

IncreaseincapitalcostsforcheckvalvebutreductioninratingofotherpipelinecomponentsEffectiveinsplittingthesurgepressureriseintwoDegreeofincreaseinmaintenanceminimalProtectspumpsfromhighestpeakpressureNonslamcheckvalvespreferredValvepitmaybeinroadwaycausingtrafficproblemsduringconstructionormaintenanceCheckvalvesarenotconsideredanadequateformofisolationandhenceshouldbeinstalledwithisolationvalvesNeedstobedeterminedatdesignstageotherwisepipelineneedstobeoutofserviceforretrofittingcheckvalveIntermediateCheckValves

Incr43NonSlamCheckValveCapitalcostincreaseFastclosingvalvereducessurgepressureatpumpReducesfatiguedamageIncreaseinmaintenancelowInherentlytroublefreeAvailableasshortorlongpatternUsedextensivelyinEuropeCanberetrofittedasvalvesstandardlengthsNonSlamCheckValveCapitalco44ComparisonofCheckValvePerformanceComparisonofCheckValvePerf45NorevaAnnulusTypeNonSlamCheckValvesNorevaAnnulusTypeNonSlamC46BypassCheckValvesIncreasecapitalcostIncreasemaintenancetoensureeffectiveoperationNeedspositivepressureupstreamtoprovideenergytofillcavitationvoidsSimpleandeffectiveforovercomingnegativepressuresDoesnotprovideprotectionforpositivepressuresCanbereadilyretrofittedBypassCheckValvesIncreaseca47BladderTypeGasAccumulatorIncreasedcapitolcostsMaintenancelevellowforbladdertypeProvidessecureprotectionforpositiveandnegativesurgepressuresBestlocatedatsourceofpressuretransienteventOverseasdesignandmanufactureCanberetrofittedLongleadtimeBladderTypeGasAccumulatorIn48Hydro-PneumaticAccumulatorIncreasedcapitalcostsMaintenancelevelhighforhydropneumatictypeBestlocatedatsourceofpressuretransienteventProvidessecureprotectionforpositiveandnegativesurgepressuresLocaldesignandmanufactureCanberetrofittedifbranchedteesfittedtopipeworkLongleadtimeHydro-PneumaticAccumulatorInc49Liquidaccumulators

IncreasecapitalcostDifficulttomodelwithouttestdataInherentlymaintenancefreeCanberetrofittedbutgenerallyalongleadtimeLiquidaccumulators

Increasec50SurgeTanks

andSurgeShaftsCommonlyusedinwatertransmissionsystemsProvidesprotectionfromnegativepressureeventsbutNOTforpositivepressuresInherentlymaintenancefreeexceptforrefillingfacilityofsurgetankTelemetryrequiredformonitoringCanberetrofittedbutgenerallyalongleadtimerequiredSurgeTanks

andSurgeShaftsCo51SurgeAnticipationValvesModeratecapitalcostComplexdevicesRequirepowerintheformofelectric,hydraulicorpneumatictooperateDonotcoverallsurgeeventsinapipelinesystemsHighmaintenancetoensurethattheyworkwhenneededVendorswhoperformsurgeanalysisandrecommendationareNOTnecessarilydesignengineersanddoNOTtakeresponsibility.Oftendonothavelatest,orhavelimitedcapability,software.CanberetrofittedhowevermoderateleadtimesSurgeAnticipationValvesModer52ReliefValves

andBurstingDiscsIncreaseincapitalcostConventionaldevicesdonotreactquicklyenoughtopreventdamagefromsurgepressureDonotprotectagainstvacuumconditionsHighlevelofmaintenanceBurstingdiscsrequirereplacementafteroperationNeedforregistrationandroutinetestingperCodeSuitableforlethalandflammableliquidsaspartofanoverallprotectionstrategyCanberetrofittedhowevermaybemoderateleadtimesReliefValves

andBurstingDis53WeakPipeSectionsCapitalcostneutralReducescelerityinsensitivesectionsReducedsurgepressuremagnitudeReducedfatiguedamageCouldbedamagedbyvacuumconditionsSuitableforlowpressuresystemsinthewaterindustryInherentlymaintenancefreeNotauniversalsolutionNeedstobedeterminedatdesignstageWeakPipeSectionsCapitalcost54IncreaseDiameterofPipelinetoReduceAverageVelocity

ReducedcelerityandsurgepressureIncreaseincapitalcostofpipe,excavation,valvesandinstrumentsIncreasedlifeoftheassetFutureaugmentationpossibleInherentlymaintenancefreeReductioninenergyofpumpingSettlingofsolidsmorelikelyNeedstobedeterminedatdesignstageIncreaseDiameterofPipeline55VariableSpeedDrives

andSoftStarters

IncreaseincapitalcostsandcomplexityLowlevelofmaintenanceIncreasedfrequencyofreplacementandupgradeProvidesNOprotectionforlossofpowerscenariosSoftstartersprotectpowersupplymorethanpipeline;thereareNOguaranteestheycanbesettolimitsurgepressuresReducedfatigueissuesfornormalstop/startLargerswitchroomrequiredtohouse

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