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GuidelineNo.:B-05(202511)
B-05SEAMLESSSTEELGAS
CYLINDERS
Issueddate:November01,2025
©ChinaClassificationSociety
Foreword
ChinaClassificationSociety(hereinafterreferredtoasCCS)ProductInspectionandTestingGuideline(hereinafterreferredtoasthisGuideline)containsthetechnicalrequirements,inspectionandtestingcriteriarelatedtoclassificationandstatutorysurveyofmarineproductstobeappliedforCCSapproval/inspection.
ThisGuidelinefreestheuserstoadoptothertestmethodsandrequirementswhichareequivalenttoorarestricterthanthisGuideline.
ThisGuidelineispublishedandupdatedbyCCS,andisreleasedat
.Yourcommentsorsuggestionsarewelcomedandmaybesenttoouremailaddressed
service@
.
Historicalversionsandreleasedate: B05(201510),October20,2015
B-05(201705),May9,2017
B-05(202211),November15,2022
Mainchanges:
Addthetestitem‘Bottomsealingtest(onlyapplicabletothebottomofcylindersmadeofsteelpipes)’intoTable7.2.
Textmodification.
B-05(202511)SEAMLESSSTEELGASCYLINDERS
10/13
CONTENTS
Application
4
Normativereferences
4
Termsanddefinitions
4
Drawingsanddocuments
5
Technicalrequirements
6
Materialsandcomponents
6
Typetest
9
Unit/batchinspection
1
2
SEAMLESSSTEELGASCYLINDERS
Application
Thisguidelineisapplicabletotheworksapprovalandunit/pathinspectionofrefillableseamlesssteelgascylindersforshipswhichareusedforcontainingcompressed,liquefiedanddissolvedgasesandforquenchedandtemperedsteelcylinderswithamaximumactualtensilestrengthoflessthan1100MPa,andwithwatercapacitiesuptoandincluding450L,andaserviceenvironmenttemperatureshallmeettherequirements.
Thisguidelineisnotapplicabletotheseamlesssteelgascylindersusedforcontainingdissolvedgasesandadsorbedgasesandcylinderpressurevesselsmountedasaccessoryontransportvehiclesandmachineryinstallations.Seamlesssteelgascylindersarenottobeusedforcontainingthemediahavingstresscorrosiontendency.
Thisguidelineisinprincipleonlyapplicabletotheapprovalandunit/pathinspectionofthebodyofseamlesssteelgascylinders,notforheadvalves.
Thisguidelineisapplicabletotheseamlesssteelgascylindersusedonships,Seamlesssteelgascylindersforoffshoreinstallationsandetc.canrefertothisGuideline.
UpontheapprovalofCCS,seamlesssteelgascylindersmaybeapprovedandunit/pathinspectedinaccordancewiththetechnicalrequirementsofrecognizedstandards.
Seamlesssteelgascylindersforspecificpurposesshallcomplywiththerequirementsofrelevantconventions,regulations,rulesandrelevantstandardsforspecificpurposes.Forexample,seamlesssteelgascylindersforinflationsystemsofinflatableliferaftsshallcomplywiththerelevantrequirementsoftheInternationalLife-savingApplianceCode.
Normativereferences
Chapter2,PartSixofChinaClassificationSocietyRulesforClassificationofSea-goingSteelShips
ISO9809-1:2019Gascylinders—Design,constructionandtestingofrefillableseamlesssteelgascylindersandtubes—Part1:Quenchedandtemperedsteelcylindersandtubeswithtensilestrengthlessthan1100MPa.
Termsanddefinitions
Forthepurposeofthisguideline,thefollowingdefinitionsareused:
HydraulictestpressurePh:thepressuretobereachedduringhydraulictest.
Yieldstrength:theupperyieldstrengthistobetakenwherethematerialtestspecimenexhibitsapparentyieldingduringthetensiletest;wherethetestspecimendoesnotexhibitapparentyielding,thespecifiednon-proportionalelongationstrengthunderthetestforce,
Rp0.2,istobetakenastheyieldstrengthofthematerial.
Batchquantity:thespecifiedquantityofsteelcylinderswhichadoptthesamedesignconditions,havethesamenominaldiameteranddesignwallthickness,aremadeofsteelofthesameheat/furnacenumberbythesamemanufacturingprocess,andarecontinuouslyheattreatedinaccordancewiththesameheattreatmentspecifications.Forquenchedandtemperedsteelcylinders,abatchcorrespondstoaquantityofnotlessthan200plusthenumberofsteelcylindersusedfordestructivetest.
Fillingratio:themaximumallowableweightofgastobefilledperunitwatercapacityofthesteelcylinderspecifiedintheapplicablestandardsforvariousfilledmedia.
BurstpressurePb:themaximumpressureofgascylindersreachedduringbursttest.
Drawingsanddocumentation
ThefollowingdrawingsanddocumentationtobesubmittedaretobesubmittedtoCCSforapproval:
Seamlesssteelgascylinderdrawings.Drawingsaretoreflecttheproducts’structuralform,maindimensions,materials,mechanicalandchemicalparameters,manufacturingandheattreatmentmethods,nominalworkingpressure,hydraulictestpressureandotherspecialtechnicalrequirements;
Seamlesssteelgascylinderdesigncalculations.Relevantcalculations,includingstrengthcalculationsofcylinderbody,baseandhead,aretobemadeinaccordancewiththedesignstandard;
Typetestplan.
Thefollowingdrawingsanddocumentationtobesubmittedaretobesubmittedforreviewwhentheinitialworksapprovalisbeingappliedfor:
Basicinformationofthemanufacturer:name,addressandproductionhistoryofthemanufacturer,typesandspecificationsofcurrentproducts,thetypes,specificationsanddeliveryconditionsoftheproductsforwhichapprovalisbeingapplied,informationonothercertificationorqualificationcertificatesobtained,etc.;
Qualitysystemdocumentsandothermanagementdocuments.Theorganizationsofthequalitysystemandproductqualitycontrolpointsaretobeclearlydefinedinthesedocuments;
Mainproduction,measuring/testingequipment.
Listofmainproductionequipment:Formingequipment;
Heattreatmentfurnace’stype,dimensions,heatingmethod,temperaturecontrollingandrecordingmethod,andarrangementoftemperaturemeasuringpoints.
Listofmainmeasuring/testingequipment
Listofequipmentforchemicalcomponentsanalysis,mechanicalproperties,mechanicaltest,metallographictest,NDT,hydraulictest,etc.(includingtheproductname,type,manufacturer,statutoryinspectionorganizationandvalidperiodofverification/calibration)
Processdocuments:
Productionprocessflowchart(qualitycontrolpointsaretobeindicated);
Operationguidancebookswithvariousworkproceduresindicatedinproductionprocessflowchart,includingthemainworkproceduressuchasforming,heattreatment,NDT,etc.;
Qualificationcertificatesoftestingandinspectionpersonnel;
Testlocationandlaboratoryqualifications(wherethetestissubcontracted,thequalificationofthesubcontractorandsubcontractagreementaretobedescribed).
Listofsuppliersofmaterialsandmainparts;
Productdescriptionandqualitycertificates(sample).
Technicalrequirements
Generaldesignrequirements
Thedesignformulausedtodeterminethewallthicknessofcylinderbodyistocomplywiththerequirementsofrecognizedstandards(e.g.ISO9809-1).
Theguaranteevalueoftheyieldstrengthofheattreatedmaterial,Reg,istobetakenfordesignofwallthicknessofpartsunderpressure,andthelimitoftheratioofyieldstrengthguaranteevalueRegtotensilestrengthguaranteevalueRmgistocomplywiththerequirementsofthestandards;
ThedesignandcalculationofthewallthicknessofthebottlebodyshallbesubjecttothehydrostatictestpressurePh;thehydraulictestpressureofthecylinderis1.5timesofthenominalworkingpressure
Ingeneral,morethantwoopeningsonagascylinderarenotallowed,andtheopeningscanonlybedesignedtobearrangedalongtheneutralaxisofthegascylinder.
ForCrMosteel,theactualmaximumtensilestrengthofcylinderbodymaterialRmaisgenerallynottoexceed1100MPa;forCMnsteel,theactualmaximumtensilestrengthRmaisnottoexceed1030MPa.Forcylindersfilledwiththemediumposingariskofhydrogenembrittlement,theactualmaximumtensilestrengthofcylinderbodymaterialRmaisgenerallynottoexceed
880MPa,ormaynotexceed950Mpawhentheactualyield-strengthratioisnotmorethan0.9.
Thebottomstructureofseamlesssteelcylindersistocomplywiththefollowingrequirements:
Thestructuralformanddimensionsaretocomplywiththerequirementsofrelevantstandards;
Thepartinconnectiontoconvexbaseistobesmoothanditsthicknessistobenolessthanthedesignthicknessofthecylinderbody;
Thereistobeatransitionalsectionbetweentheannulatedshellofconcavebaseandthecylinderbody.Theconnectionoftransitionalsectiontocylinderbodyistobesmooth.
Thedesignofconvexbaseandconcavebaseistobesubjecttofatiguetestbymeansofcyclicpressurization.Thedesignofcylinderbasesisconsideredqualifiedprovidedthatthecylinderbasescanwithstand80000cyclesofpressurizationwiththeupperlimitofcyclicpressurebeingatthenominalworkingpressure,or12000cyclesofpressurizationwiththeupperlimitofcyclicpressurebeingatthetestpressure,Orforcylinderswithahydraulictestpressureph>450bar,theuppercyclicpressuremaybereducedtotwothirdsofthistestpressure.Inthiscase,thecylindersshallwithstand80000cycleswithoutbeingdamaged,thedesignisnottobeadoptedifthecylinderbaseshavenotpassedthesaidtestsuccessfully.
Thethicknessofsteelcylinderopeningistobemeasuredinordertoensurethattheopeningwillnotbedeformedwhensubjecttothemomentofvalve-tighteningforcecoupleandtheadditionalexternalforceofneckringriveting.
Theinternalthreadsofcylinderopeningsaretocomplywiththefollowingrequirements:
Thethreadaretocomplywiththerequirementsofrecognizedstandards.
Thenumberofusefulordinarythreadsistobesuchthattheshearsafetyfactorcalculatedatthehydraulictestpressureofsteelcylinder,Ph,isatleast10,andnolessthan6.
Generalrequirementsformanufacturing
Themanufactureofmarineseamlesssteelgascylinders,inspections/testsuponcompletionaretocomplywiththerequirementsofCCSRulesforClassificationofSea-goingSteelShips,approveddrawingsandrelevantstandards.
Themanufacturersofmarineseamlesssteelgascylindersaretointroducethemanufacturingprocess,describethemanufacturingtoolshavingsignificantimpactonproductqualitysuchasthepressheadforaircylinderpressinganddrawing,moldplateormoldtoolforshellnosingduringrotarypressingormoldpressing,andspecifyotherrequirementsforprocessverificationbeforetheproductisputintoservice,regularinspection,repairandreplacementwhentheproductisinservice,etc.
Thecylinderbodyisnotallowedtobeweldedorrepaired.Thecrack,inclusion,nonfusionandotherdefectsontheinnersurfaceofthecylinderfromthetubeshallberemovedbymechanicalmillingandothermethods.Thetreatmentofsurfacedefectsofthecylinderbodyshallcomplywiththerequirementsofrelevantrecognizedstandardsforgascylinders.
Thefillingratioistobeconsistentwiththestrengthofcylinderbodyandalsocomplywiththerequirementsoftheconventions,regulations,rulesandrecognizedstandardsinvolvedintheuseofgascylinders.
Materialsandcomponents
Thematerialusedforthemanufactureofgascylindersshallbesteel,otherthanrimmingquality,withnon-ageingpropertiesandshallbefullykilledwithaluminiumand/orsilicon.Incaseswhereexaminationofthisnon-ageingpropertyisrequiredbythecustomer,thecriteriabywhichitistobespecifiedshouldbeagreedwiththecustomerandinsertedintheorder.
Thematerialofcylinderbodyistobecompatiblewiththegasintendedtobefilled.RefertoISO11114-1forcompatibilityofcylindermaterialwiththegas;
TheSelementcontent(massfraction)ofthecylinderbodymaterialobtainedthroughheatanalysisisnottoexceed0.010%andthePelementcontent(massfraction)thereofobtainedthroughheatanalysisisnottoexceed0.020%.AndthesumofS+Pcontentpercentagesisnottoexceed0.025%;
Thelimitvalues(thedifferencebetweenthemaximumcontentandtheminimumcontent)ofthechemicalcompositionofcylinderbodymaterialarenottoexceedthevalueslistedinthetable
below:
ChemicalCompositionTable Table6.4
Element
Maximumcontent(massfraction),%
Limitvalue(massfraction),%
C
<0.30
0.06
≥0.30
0.07
Mn
--
0.30
Si
--
0.30
Cr*
<1.50
0.30
≥1.50
0.50
Ni*
--
0.40
Mo*
--
0.15
Notes: ①Therequirementsinthetableabovemustbecompliedwithwheretheelementmarkedby“*”arealloyelementsofthesteel;
②Themaximumcontentofanyintentionallyaddedelementistobereported;
③TotalcontentofV+Ni+Ti+B+Zrisnottoexceed0.15%.
Thecylinderbodyisgenerallytobemanufacturedwithnationallyorinternationallyrecognizedsteelusedforcylinders.TypicalrecognizedsteelsincludeCrMosteelandCMnsteel.
Roughrolledbilletsorsteelbilletsaretobesubjecttomacrostructureexaminationanddefectssuchasflakers,residualshrinkagecavity,delamination,airbubble,foreignmattersandimpurityinclusionarenotallowed.Thecenterporosityistobenogreaterthangrade1.5andsegregationnogreaterthangrade2.5.Forseamlesssteelpipes,thewallthicknessdeviationisnottoexceed
-10%~+15%ofthenominalwallthicknessandthesteelpipesaretobe100%satisfiedbyUT.
Typetest
Samplingprincipleoftypetest
Seamlesssteelcylindersaretobetypetestedaccordingtodifferenttypes.Cylindersareconsideredtobeofdifferenttypesinanyoneofthefollowingcases:
Productionprocessflowisdifferent;
Materialdesignationisdifferent;
Heattreatmentprocessisdifferent;
Structuralformofcylinderbottomandratioofbottomthicknesstocylinderdiameteraredifferent;
Theoveralllengthofthecylinderhasincreasedbymorethan50%(cylinderswithalength/diameterratiolessthan3shallnotbeusedasreferencecylindersforanynewdesignwiththisratiogreaterthan3);
Theoutsidediameterorminimumguaranteethicknessofthecylinderisdifferent;
Thehydraulictestpressureisdifferent(thedesignonthesamebasiswithonlyhydraulictestpressurebeingreducedisnottobeconsideredasnewdesign);
Theminimumguaranteedyieldstrengthand/orminimumguaranteedtensilestrengtharedifferent.
Incaseoftaperedthreadsthetorquetestshallbeperformed;incaseofparallelthreadsthecalculationoftheshearstrengthshallbeperformed,ifthediameteroftheinternalthreadhasincreasedby50%ormore,thepressurecyclingtestontwocylindersshallalsobeperformed.
Foreachtypeofgascylindersforwhichapprovalistobeapplied,atleast50gascylindersaretobemanufacturedbytheapplicantandtestedinaccordancewiththecorrespondingrequirementsofthetablein7.2.
Formarineseamlesssteelgascylindersfortypetest,theacceptanceofrawmaterials,mainmanufacturingprocess,inspectionandtest,andtransferofrelevantmarksmustbecarriedoutunderthesupervisionofthesurveyorandtheresultsthereofaretocomplywiththerequirementsofCCSRulesforClassificationofSea-goingSteelShipsandapproveddrawings.
Typetestitemsandrequirements
Typetestitemsandrequirements Table7.2
Testitem
Testquantity
Testrequirements
Rawmaterialinspection
Eachheatoreachbatch
Eachbatchofrawmaterialsaretobefurnishedwithproductqualitycertificates;
ElementstobeanalyzedaretoincludeC,Si,Mn,P,S,Nb,V,Ti,Cr,Ni,Mo,Cu,Al,B,Zr,andpurposefullyaddedelements;
Forseamlesssteelpipes,visualinspection,wallthickness
inspection;
Internalandexternalvisualinspectionof
gascylinders
Eachcylinder
Theinternalandexternalsurfacesoffinishedgascylindersarefreeofdefectsthatmayaffectthesafeuseofgascylinders,for
details,see8.3ofISO9809-1:2019.
Inspectionofdimension,shapeandpositiontolerances,neckthreadsinspection
Eachcylinder
Dimensionalinspection:
Foreachcylinderfortypetest,wallthickness,outerdiameterandheightofcylinderbody,thicknessandcentraldepth(applicabletoconcavebase)ofcylinderbasearetobemeasured.Theresultsaretobeconsistentwiththerequirementsof7.3~7.6,8.1,8.2ofISO9809-1:2019andCCSapproveddrawings.
Thethicknessandouterdiameterofthetwocylindersformechanicalpropertytestshallalsobemeasuredaccordingto
7.3to7.6,8.1and8.2ofISO9809-1:2019andtheapproveddrawings,foreachsteelcylinder,threecrosssections,namelytheupper,middleandlowercrosssections,aretobetakenalongthelengthofcylinderbody.Thewallthicknessandouterdiameteraretobemeasuredrespectively.Wallthicknessofeachcrosssectionistobemeasuredatfourmeasuringpointsevenlydistributedalongthecircumference.Theouterdiameteristobemeasuredfortwotimesverticallyandcrosswise.Thethicknessofcylinderbaseistobemeasuredatonemeasuringpointlocatedinthecenterofthebase.Forconcavebase,thethicknessoftheearthingpointisalsotobemeasuredatthefourmeasuringpointsevenlydistributedalongthecircumference.Thewallthicknessmeasuredatvariouspointsistobenolessthantheminimumthicknessguaranteevalue.
2.Formandpositiontolerancesaretocomplywiththerequirementsof8.5~8.9ofISO9809-1:2019.
3.Neckthreadsinspectionshallconformtotherequirementsof8.9ofISO9809-1:2019.
Testitem
Testquantity
Testrequirements
Hardnesstest
Eachcylinder
Hardnessistobetestedatthreepointsrespectivelylocatedintheupper,middleandlowerportionsofthecylinderbodyandtheresultsaretobeconsistentwiththerequirementsof11.3of
ISO9809-1:2019andapproveddrawings.
Ultrasonictest
Eachcylinder
Tobeinaccordancewith8.4ofISO9809-1:2019orrelevantrecognizedstandards.
Magneticparticleinspection(whenapplicable)
Eachcylinder
Ifrequiredbythestandardsthatadopted,theresultsshallconformtotherequirementsofthestandards.
Tensiletest
2cylinderstobetakenrandomly
1test
pieces/cylinder
Tobeinaccordancewith10.2ofISO9809-1:2019and
approveddrawings.
Bendingorflatteningtest
Bending:2testpieces/cylinder,flattening/ringflattening:1test
piece/cylinder
Tobeinaccordancewith9.2.4ofISO9809-1:2019.
Impacttest
1group3test
pieces/cylinder
Tobeinaccordancewith10.3ofISO9809-1:2019and
approveddrawings.
Basecheck
1test
piece/cylinder
Tobeinaccordancewith9.2.3ofISO9809-1:2019.
Hydraulicbursttest
2cylinderstobetaken
randomly
Tobeinaccordancewith10.4ofISO9809-1:2019.
Pressurecyclingtest
3cylinderstobetaken
randomly
Tobeinaccordancewith9.2.2ofISO9809-1:2019.
Hydraulictestand
Capacitycheck
Eachcylinder
Tobeinaccordancewith11.2,11.5ofISO9809-1:2019.
Neckringtorquetest
(whenapplicable)
1cylindertobetakenrandomly
Tobeinaccordancewith7.8ofISO9809-1:2019.
Torquetestfortaper
threadonly
1cylindertobetakenrandomly
Tobeinaccordancewith9.2.5ofISO9809-1:2019.
Bottomsealingtest(onlyapplicabletothebottomofcylindersmadeofsteelpipes)
Eachcylinder
Anappropriatetestdeviceisusedtopressurizethecentralareaoftheinnersurfaceofthebottomofthecylinder,Thepressurizedareashouldbeatleast1/16ofthebottomareaofthecylinder,andthediameterofthepressurizedareashouldbeatleast20mm.,Thetestmediumcanbecleanairornitrogen.Thetestpressureisthenominalworkingpressureof
thecylinder,andtheholdingtimeisnotlessthan1min.Thetestareaatthebottomofthecylinderissubmergedinwaterandthereshallbenoleakage.Thistestcanbereplacedbyan
overallairtightnesstest.
Testitem
Testquantity
Testrequirements
Airtightnesstest(when
applicable)
Eachcylinder
Ifrequiredbytheapprovedstandards,theresultsshall
conformtotherequirementsofrelevantrecognizedstandards.
Unit/batchinspection
Generally,unit/batchinspectionofmarineseamlesssteelgascylindersistobecarriedoutafterworksapproval,theunit/batchinspectionofunapprovedseamlesssteelgascylindersistobecarriedoutaccordingtotherequirementsfortypetestofthisguideline.
Theunit/batchinspection(see3.1(6)forthedefinitionofbatchquantity)ofseamlesssteelgascylindersafterCCSapprovalistobecarriedoutinaccordancewiththeproductinspectionplanalreadyapprovedduringtheapproval.Thetestitemslistedinthetable8.2aretobeincluded:
Typetestitemsandrequirements Table8.2
Testitem
Testquantity
Rawmaterialinspection
Eachheatoreachbatch
Internalandexternalvisual
inspectionofcylinder
Eachcylinder
Inspectionofdimension,shape
andpositiontolerances,neckthreadsinspection
Eachcylinder
Hardnesstest(at1measuring
pointonthecylinderbody)
Eachcylinder
Ultrasonictest
Eachcylinder
Tensiletest
1cylinder/batch
1time
Bendingorflatteningtest(when
applicable)
Bending:2times
Flattening/ringflattening:1time
Impacttest
1group3times
Bursttest
1cylinder/batch
HydraulictestandCapacity
check
Randominspection
Dissectiontestofcylinderbase
(whenapplicable)
1cylinder/batch
Bottomsealingtest(onlyapplicabletothebott
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