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1ShellandTubeGeometryShellandTubeGeometry2ShellandTubeGeometryContents•Standards•Shellandheadtypes•Tubes:arrangement,type,selection•Baffles:type,cut,orientation•Clearances•Fluidallocation3ShellandTubeGeometryStandards•ThemechanicaldesignandconstructionofS&TexchangersisusuallybasedonTEMA7thEdition1988.•TEMAsupplementstheASMEPressureVesselcode.•TEMAprovides3letterdesignationShellFrontendstationaryheadtypeRearendheadtype4ShellandTubeGeometryEFOne-passshellTwo-passshellwithlongitudinalbaffleShelltypes•E-typeshellshouldbeusedifpossiblebut•Fshellgivespurecounter-currentflowwithtwotubepasses(avoidsverylongexchangers)Note:longitudinalbafflesaredifficulttosealwiththeshellespeciallywhenreinsertingtheshellaftermaintenance5ShellandTubeGeometryMoreshelltypes•Oftenonlyusedforhorizontalthermosyphonreboilers(withtheshell-sideflowupwards)•Longitudinalbafflethenmoreadistributionplate-maybeperforatedGHSplitflowDouble-splitflow6ShellandTubeGeometryJXKStillmoreshelltypes•J&XgivelowshellsideDp•DividingJcalledIbyHTFSDividedflowCrossflowKettle-typereboiler7ShellandTubeGeometrySummaryofshelltypes•E-typeshellsarestandard•GandHshellsarenormallyonlyusedforhorizontalthermosyphonreboilers•JandXshellsareusedifallowablepressuredropcannotbeachievedinanEshell•Forservicesthatneedmultipleshellsandremovablebundles,Fshellsshouldbeconsideredasalternative•Ktypeisonlyusedasareboiler•NotethatTASCalsohandles“double-pipe”exchangers8ShellandTubeGeometryFrontandrearheadsRearHeadShellTubebundleFrontHeadBES9ShellandTubeGeometryFrontheadtypesABChannelandremovablecover平盖管箱Bonnet(integralcover)封头管箱•A-typeisstandardfordirtytubeside•B-typeforcleantubesideduties.Useifpossiblesincecheapandsimple.10ShellandTubeGeometryMorefrontheadtypesCN•C-typewithremovableshellforhazardoustube-sidefluids,heavybundlesorservicesthatneedfrequentshell-sidecleaning可拆卸管束与管板为一体的管箱•N-typeforfixedforhazardousfluidsonshellsideChannelintegralwithtubesheet11ShellandTubeGeometrySummaryoffrontheadselection•Btypestandardforcleantubesidefluids•Atypestandardfordirtytubesidefluids•ConsiderCtypefor•Hazardoustubesidefluids•Heavytubebundles•Frequentshellsidecleaning•ConsiderNtypeforfixedtubesheetexchangerswithhazardoustubesidefluids•ConsiderDtype(orbonnetweldedtotubesheet)forhighpressure•Considerconicalforsingletubepass(notactuallyaTEMAtype)12ShellandTubeGeometryRearheadtypesThesefallintothreegeneraltypes•fixedtubesheet(L,M,N)similarto(A,B,C)•U-tube•floatinghead(P,S,T,W)(填料函式浮头，钩圈式浮头，可抽式浮头，套环填料函式浮头UsefixedtubesheetifDTlow*,otherwiseuseothertypestoallowfordifferentialthermalexpansionYoucanusebellowsinshelltoallowforexpansionbutthesearespecialitemswhichhavepressurelimitations(max.35bar)*Forpreliminaryscopingstudies,takebelow500Casbeinglow13ShellandTubeGeometryFixedheadtypesGivesmallshell-to-bundleclearance14ShellandTubeGeometryFloatingheadtypesThassimplerconstructionthanSbutgiveslargeshellwithlargeshell-to-bundleclearanceSplitbackingring15ShellandTubeGeometryPandWfloatingheads•Rarelyusedexceptonsmallunits•NotethatyoucannothaveapasspartitionplateinaWtypethuslimitingitto2(or1)pass16ShellandTubeGeometryRearheadselection•fixedtubesheet(L,M,N)-lowshell-baffleclearance•U-tube-simpledesignbutdifficulttoclean-lowshell-baffleclearance•floatinghead(P,S,T,W)-Smostcommon•Sgiveshighershell-to-baffleclearance•Tgiveshighestshell-to-baffleclearance•Wlimitedto2(or1)passesU-tube17ShellandTubeGeometryShell-to-baffleclearance0.51.01.52.02.50Shelldiameter,mClearance,mm015010050FixedandU-tubePandST18ShellandTubeGeometryRearHeadSelection•Fixedtubesheets(L,M,N)providedthat•nooverstressingduetodifferentialexpansion•shellsidedoesnotneedmechanicalcleaning•Fixedtubesheetwithbellowsprovidedthat•shellsidefluidisnothazardous•shellsidepressureisbelow35bar(500psi)•shellsidedoesnotneedmechanicalcleaning•U-Tubeprovidedthat•tubesidewillnotneedmechanicalcleaning•countercurrentflowisnotrequired(unlessFshellok)•SplitbackingRingFloatingHead(Stype)•P,T,Wfloatinghead19ShellandTubeGeometryTEMAdesignation-exampleBES20ShellandTubeGeometryShelldiameter•Forsizesupto610mm(24in)normallyusestandardpipesizes•British/USstandardsizesare152,203,254,305,356,406,508and610mm(6,8,10,12,14,16,18and24in)nominalbore•Forsizes356mm(14in)andaboveactualinsidediameteris19mm(0.75in)less•152mm(6in)minimumsizeformostprocessapplications21ShellandTubeGeometryShelldiameter(cont.)•Largershellsmadefromrolledplate•Sizelimitedbydrillingandmachiningcapacityofmanufacturerbutcanbeupto3000mm(118in)ormore•Forrolledshellsanydiameterpossiblebutmostdesignersprefertoworkinstepsof50mm(2in)•Notethatmechanicaldesignrequiresthattheshellthicknessisroughlyproportionaltotheshelldiametersobigshellscanbeexpensive22ShellandTubeGeometryTubeSelection•Outsidediameter•TEMAlists9standardsizes,6.35to50.8mm(0.25to2in)•Onlytwoincommonuse•19.05mm(0.75in)standard•25.4mm(1in)forlowtubesidepressuredrop•Wallthickness•TEMAgiverecommendedvalues(adequatefornormaltemperaturesandpressures)•ForhighinternalpressurerefertoTEMA•Forhighexternalpressuresrefertopressurevesselcodes•Notethatcodesrefertominimum(notavera