Thepurposeofthepresentsectionistogiveanunderstandingofthestresscomponentsandthephysicaleffectsthatareinherentinpipelinedesignformulasusedforwallthicknesssizingandcapacitycontrol.Thereareseveraldifferentdesigncodesinuseforwallthicknesssizing,applyingslight...[继续阅读]

    ThestresscomponentsinthepipewallduetointernalandexternalpressureandexternalloadsareshowninFigure3.1.Figure3.1StresscomponentsinthepipewallTheσψψ(hoop)stresscanbedescribedbythinwalledorthickwalledshelltheories.Thethickwalledtheoryisbasedonradialequilibrium...[继续阅读]

    Differentstandardsuseslightlydifferentformulationstodealwiththeburstingcriteria.Anexcellentreviewofthesearefoundin(BaiandBai,2005).Inthe(DNV,2012)formulation,therequiredwallthicknesstoavoidexcessiveyieldinginthehoopdirectionisbasedonthefollowingdesignform...[继续阅读]

    Theexternalpressurecollapseequationappliedin(DNV,2012)isbasedoncalibrationagainsttestdata.Here,thebackgroundfortheTimoshenkoequationforcollapseofcircularrings(TimoshenkoandGere,1963)willbepresentedasitprovidesaneasyinterpretationofthephysicaleffectsinvolv...[继续阅读]

    Thebucklingdesigncriteriatobeappliedforcombinedloadingdependsontheloadcondition,whetheritisdisplacementcontrolledorforcecontrolled.ThetwoloadconditionsareillustratedinFigure3.3.(a)Displacementcontrol(b)ForcecontrolFigure3.3Illustrationofdisplacementandloa...[继续阅读]

    ThefatigueduetocrackgrowthintheweldsresultingfromcyclicloadscanbecalculatedeitherbyapplicationoffracturemechanicsprinciplesorbymeansoftheMinersumapproachusingfatiguedataobtainedfromtesting.ByapplicationoftheMinersumapproach,thedesigncriterionisformulateda...[继续阅读]

    Thecapacityequationsgivenaboverequirethatsufficientcapacityoftheweldsareobtained.Theweldcapacityisgovernedbymaterialselection,whichweldingmethodtobeappliedandtheperformanceoftheNDTequipmentusedtocheckthequalityofthewelds.Alltheseparametersneedtobeevaluate...[继续阅读]

    Theunderstandingofpipeperformancecharacteristicsandrelatedfailuremodesisimportantforobtainingareliabledesignofflexiblepipesystems.Theexperiencegainedfromflexiblepipeapplicationsoverthelasttwodecadeshasidentifiedasignificantnumberoffailuremodes.Theperforma...[继续阅读]

    Thenon-bondedflexiblepipeconsistsofalayeredstructurewhereeachlayerisfreetoslide(undertherestraintoffriction)relativetoeachother.EachlayerhasitsspecificfunctionasdescribedinSection1.1.Inordertounderstandthemechanicalbehaviourofflexiblepipesitisimportanttoc...[继续阅读]

    Thetensilearmourconsistsofflatrectangularprofiles,withroundedcornersforavoidingnotcheffects.Foreachlayer,allwiresaresimultaneouslycoldformedontothepipesurface,40～80wiresineachlayeratlayangles29°～55°.ThefractionfilledratioFfisusuallyaround0.9.Forthetensile...[继续阅读]