Flanges are circular fittings used to connect pipes, valves, pumps and other equipment to make a piping system. They are typically welded or threaded together with bolts and gaskets to provide a seal. There are various types of flanges such as slip-on, weld neck, blind, socket weld, reducing, threaded, square, long neck weld, expander, spade/ring spacer, weldo, orifice, loose, high hub blind, screwed, plate and raised face flanges. Each type has a different design suited for various piping system applications depending on factors like size, pressure and temperature requirements.
Research Methodolgy & Intellectual Property Rights Series 2
What are flanges
1. What are Flanges?
Ms Flange are usedtoconnect valves,pipes,pumpsandotherequipmenttomake a pipework
system.Typicallyflangesare weldedorthreaded,andtwoflangesare connectedtogetherbybolting
themwithgasketstoprovide a seal thatprovideseasyaccesstothe piping system.TheseFlanges
are available invarioustypessuchassliponflanges,weldneckflanges,blindflanges,andsocket
weldflanges,etc.Belowwe have explainedthe varioustypesof flangesusedinthe pipingsystems
dependsontheirsizesotherfactors.
Typesof Flanges
SliponFlange Isfundamentallyaringplacedoverthe endof the pipe,withaflange face extending
fromthe endof the pipe by sufficientdistancetoapplyaweldedbeadtothe innerdiameter.Asthe
name suggeststhese flangesslip overapipe andhence knownasSlipOnFlanges.A slip-onflangeis
alsoknownas SO flange.It’sakindof flange thatare slightlybiggerthanthe pipe andslidesoverthe
pipe,withinternal design.Since the innerdimensionof the flangeisslightlybiggerthanthe external
dimensionof the pipe,the topandbottomof the flange canbe connecteddirectlytoequipmentor
pipe byfilletweldingthe SOflange.Itisusedtoinsertthe pipe intothe flange’sinnerhole.Slip-on
pipe flangesare usedwitha raisedor flatface.Slip-OnFlangesare asuitable choice forlow-pressure
applications.Sliponflange isexcessivelyutilizedinmanyfluidpipelines.
WeldNeckFlanges
WeldNeckFlange alsoknownasa taperedhubflange orhigh-hubflange.Weldneck flange(WN
flange) hasa neckthat can move the pipe tension,therebyreducingthe pressure gatheredinthe
bottomof the flange.Itiscompatible withthe pipelineswhichoperate athighorlow temperatures
and withstandhighpressure.WeldingNeckFlangesare effortlesslyidentifiableatthe longtapered
end,whichslowlypassesthroughthe wall thicknessfromapipe or fitting.The longtaperedhub
providessignificantshieldingforuse inmultipleapplicationsinvolvinghighpressure,sub-zero
and/orhightemperatures.A weldneckflangecomprisesof acircular fittingwithaprotrudingedge
aroundcircumference.WeldNeckFlangehasbeenusedsuccessfullyatpressuresupto5,000 psi.
SocketWeldFlanges
The Socketweldflangesare onlyconnectedonthe outside byone filletweld,andare oftennot
advisedforcritical services.Theseare mostlyusedforthe small-bore lines.Theirstaticstrengthis
equivalenttoSlipOnflanges,buttheirfatiguestrengthis50 percenthigherthandouble-weldedSlip
On flanges.Forthistype of flanges,the thicknessof the connectingpipeshouldbe definedtoensure
properbore length.Before welding,agapmust be formedinthe socketweldflange betweenthe
flange orfitand the pipe.The objective of aSocketWeld’sbottomclearance isgenerallytominimize
the residual pressure atthe weldrootthatcouldoccur duringweldmetal solidification.The socket
weldflange’sdrawbackisthe rightspace,whichmustbe made.The crack betweenthe pipe andthe
flange cancause corrosionproblemsbycorrosive products,andmostlyinstainlesssteel pipe
systems.Thisflange isnotallowedinsome processes.Alsoforthisflange,thatprinciple mustalways
be weldedfirstbyapipe and thensimplybyafitting.
BlindFlanges
BlindFlangesare producedwithoutabore and are utilizedtoblankoff the endsof pipes,valvesand
pressure vesselopenings.Fromthe pointof view of internalpressureandboltloading,the most
overstressedflange typesare blindflanges,especiallyinbiggersizes.Nevertheless,mostof these
pressuresare bendingtypesnearthe centerand,asthere isno standardizedinnerdiameter,these
2. flangesare ideal forhigherpressure temperaturesystems.The functionof these flangesisto
obstructa segmentof the pipe ora nozzle ona vessel thatisnot inuse.The nozzle will oftenbe
blankedoff withablindflange forpressure checksinaplantor simplybecause the consumerdoes
not needall the nozzlesthatwere providedonthe tank.
Spectacle BlindFlanges
Spectacle Blindsare typicallyusedforpermanentlysplittingpipe networks,orsimplyforconnecting
to each other.A Spectacle Blindisasteel plate whichhasbeencutintotwo discsof a certain
thickness.
The two discsare connectedtoeachother bya part of steel similartothe piece of apair of glasses
on the nose.The name derivesfromthe factthat the assemblylookslikeeyeglassesor“spectacles.”
One of the discsisa solidplate,while the otherisaringwho’san innerdiameterequivalenttothat
of a flange.Spectacle Blindsare usedinstructuresthatneedtobe segregatedfromother
installationsonaregularbasis.The Spectacle Blindisusuallyinstalledinthe “open”positionsothat
the flowthroughthe pipe isfeasible.If the Spectacle Blindisrotatedinthe “close”position,the pipe
isblankedoff andno flowisfeasible.
Lap JointFlanges
Lap jointflangesare usedwithstubendswhenthe pipe ismade of expensivematerial.Fore.g.,a
carbon steel flange canbe addedtothe stainlesssteel pipe systembecause the flange will notcome
intocontact withthe substance inthe pipe.The stubendswill be butt-weldedtothe pipe andthe
flangeswill remainloose.The innerradiusof these flangesisbevelededgetoclearthe stubend
radius.Lap jointflangesare almostsimilartothe SlipOnflange,exceptforthe radiusatthe
intersectionof the flange face andthe bore toaccommodate the flangedportionof the StubEnd.
Theirabilitytoholdpressure islittle,if any,strongerthanthatof SlipOnflanges,andthe fatigue life
of the assemblyisonlyone-tenththatof the WeldNeckflanges.Lapjointflangeistherefore usedin
low-pressure andnon-criticalapplications.
ReducingFlanges
Reducingflangesisdesignedforwhen the size of the pipe changes.The flange(dimensions)
predominantlymatchingthe largerpipe size (NPT) buthavingasmallerbore matchingthe smaller
pipe size (NPT).These flangesgenerallycome inneckflangesthatare blind,slip-on,threaded,and
weld.Theyare available inall pressureclassesandofferanexcellentalternativetoconnectingtwo
differentpipe sizes.Thistype of flange shouldnotbe usedif anunexpectedchange,suchasat a
pump,wouldcause unnecessaryturbulence.
Designedforuse inpipingsystemof changingdiameters.A reductionflange consistsof aone-
specifieddiameterflangewithaseparate andsmallerdiameterbore.The flange will have
measurementsof the greaterpipe sizeexceptforthe bore andhub dimensions.Reducingflanges
are attachedby welding,gluingorclampingflangesof the same size suppliedwithdifferent
connectingpieces.
ThreadedFlanges
Threadedflangeslooknearlyidentical toSlip-Onflangesbutthe keydifferenceisthatthe threaded
flange hasbeenboredoutto match the inside diameterof aparticularpipe.Threadedflange isa
type of flange thathas taper pipe threadsinitsbore conformingtoASME B1.20.1 and can be usedin
pipingsystemswhereweldingflange ontothe pipe isnotpossible,suchas highlyexplosiveareas
3. where weldingcandeveloppotential risk.The threadedflange isfixedontoapipe thathas
additional threadstothe taperpipe Galvanizedandcast-ironpipingiscommonlyusedwiththreaded
flanges.Inveryhighpressure systemsandforsmall diameters,threadedflangescanbe usedand
theirmainbenefitisthattheycanbe installedwithoutwelding.
Square Flanges
Square flangesare made incompliance withJISB2291/JIS F7806 standards.Square flangesare often
usedforconnectionsbetweenpipe-to-pipeandpipe-to-components.Theyare mostoftenusedin
the line of hydraulicsystemswhereapassage of fluidsoccursandare made of twomaterialswhich
are steel andstainlesssteel.A full setof square flangesismade upof the oring,bolts,female flange
(oringside),andmale flange (flatside).The female flange islistedaspartA. Part B identifiesmale
flange.Andthe full setisAB.
There are three typesof Square Flangesunderthisstandard:SHAB – Usedwithhexagonhex bolts,
largerflange bodysize,SSAB –Used withsocketcap screw,smallerflange bodysizethanSHAB,LSA
– Oringside only,Lshapedinternal flow.
Long NeckWeldFlanges
In highpressure andhigh(orfluctuating) temperature situations,primarilyinthe oil andgas
industrythe longweldedneckflanges(oftenabbreviatedtoLWN) are used.The longneckguides
the pipe intothe flange itself andoffersreinforcementthatisnotpossible withastandardwelded
neckflange.Thisreinforcementisquite essential forthe safetyof industrial,commercial andeven
residentialhighpressuresystems.Unlikemanyothertypesof flanges,LongWeldNeckshave no
schedule bores.Typically,longweldedneckflangesare made withsquare cutstoreplace the pipe,
and notto be weldedtothe pipe.
The long weld-neckflangeisgenerallythe anchorsforwater-mainsorgas sourcesbeingpumped
intoa larger networkof pipes,likethose inafactoryor an apartmentbuilding.
ExpanderFlange
An expanderflange,referredtoasEXPF,representsaweldedneckflangebutthe hubextendstoa
largersize (one ortwo sizes).If youhave limitedspace orjustneedtoconnectto a widerpipe
diameter,itprovidesaconvenientplace forequipment,pumps,andvents.The compactsize saves
space comparedwitha reducer-weldingneckflange whichcaneliminatethe use of flange and
reducer.Expanderflangesare alsoconsideredacost-effective alternative tousingthe reducer-
weldingneckflangeseparately.Pressure ratingsanddimensionscomplywithANSI/ASMEB16.5.
Expanderflange hasa raisedface.Installingthe ExpanderFlangerequiresasingle butt-weld.
Spade and RingSpacerFlange
Spade and RingSpacer Flange are essentiallysimilartoSpectacle Blinds,withthe exceptionthat
theyare notboth connected.Spadesandspacersare usedinsystemswhere maintenance isn’toften
requiredortheyare oftenusedinlarge pipe size applications.Spadescanweighhundredsof pounds
dependingonthe flange sizesandthe Stresslevels.Inordertoavoidadditional weight,the flange
connectionisspecificallychosennotforthe Spectacle Blind,butfor2 separate parts.High
maintenance of the pipe systemcanbe a majorreasonto temporarilyreplace the RingSpacerwitha
spade.
WeldoFlange /NipoFlange
4. A Nipoflange isacombinationof weldolet,nipoletandWeldingNeckflange &widelyusedinthe
pipe industrylike aweldoletora nipoletfora90° branchconnection.Onthe run pipe side a
weldoflange isdesignedlikeaweldoletandonthe otherside,ithasa flange connection.Thatmeans
the branch connectiononthe run pipe side isaweldingconnection.InaNipoFlange the branch
connectiononthe run pipe side isaweldingconnectionandonthe otherside,ithas a flange
connection.
Orifice Flanges
Orifice Flangesare usedwithorifice metersforthe purpose of measuringthe flow rate of either
liquidsorgasesinthe respective pipeline.Pairsof pressure “Tappings”,mostlyon2sides,directly
opposite eachother,are machinedintothe orifice flange.Orifice Flange Unionsare designed&
manufacturedtoAmericanGas Association(AGA),ASME,andInternational Societyof Automation
(ISA) recommendations.Orifice Flangeare availableinwide arrayof the followingtypes:RaisedFace
weldneckorifice flanges,RaisedFace slip-onorifice flange,Ring-Typejointweldneckorifice flanges,
Cornertap orifice flanges.
Loose Flanges
A loose flange isadevice thatisweldedtothe endof a piece of pipe tomake half of a flanged
coupling.The componentcanbe made of carbon steel orstainlesssteel tosuitthe intended
specification,consistingof aflatsteel forgingwithboltholesaroundthe perimeterandanopening
inthe centerthe size of the pipe thatis supposedtobe weldedontothe loose flange.Thereare
loose flange typesare fittoinuse elbows,valvesandalmostanytype of pipelinecomponent.
HighHub BlindFlanges
The HighHub BlindFlange isbeingusedtoseal the endsof the pipe structures.It’sa kindof circular
plate withnocenterholdbut withall the rightboltholes.The highhubblindflange isavailable ina
varietyof sizesandmaterialsandisusedto provide aconstructive closeratthe endsof pipes,valves
or nozzles.Whensealed,thisflangeallowsyoutoeasilyaccessthe line.Sometimesthe highhub
blindflange canbe speciallybuiltormachinedtomatchthe nominal size of the pipe towhichthe
reductionis made.Thisreductioncouldbe areductioninthreadsor a reductioninwelds.Oftenhigh
hubblindflangesare suppliedwithNPTfittingswhichallowthe installationof pressure test
connections.Consideringfactorssuchasinternal pressure andboltloading,highhubblindflanges
are the moststressedof all typesof flanges,particularlyinthe largersizes.
ScrewedFlanges
Screwedflange are alsoknownasa ThreadedFlange,anditishavinga threadinside the flange bore
whichfitsonthe pipe withmatchingmale threadonthe pipe andthese flangesare mostlyusedin
utilityservicessuchasair and water.Screwedflange isoftenusedforrequirementsonsmall
diameter,highpressure.Screwedflangeswithahubhave issuedrequirementsrangingfrom1/2′′ to
24′′. Pressure class:Class150 to Class2,500, PN 2.5 to PN 250 and Facing:RF / RTJ
Screwedflangesare threadedinabore that matchesthe pipe’sexternal thread.Screwedflangesare
usedwithexternal threadedpipes.The advantage of these flangesisthattheycanbe mounted
withoutwelding.
Plate Flanges
OftenknownasFlat flanges,the Plate Flangehasa gasketsurface inthe same plane as the face of
the boltingcircle.Itisalsocalledflat-facedflange.Applicationsusingflatface flanges are oftenthose
5. inwhicha castingismade of the matingflange orflangedfitting.Flatface flangesare usedwhenthe
counter-flangesare flatface.ThisconditionhappensprimarilywhenconnectedtoCastIron
equipment,valvesandspecialties.ASMEB31.1 statesthat whenconnectingflatface castiron
flangestocarbon steel flanges,the raisedface of the carbonsteel flange mustbe removedanda full
face gasketis needed.
Flange FacingType & Finish:
FlatFace
In the same plane,the FlatFace flange hasa gasketsurface as the face of the boltingcircle.
Applicationsusingflatfacial flangesare oftenthose inwhichcastingismade of the matingflange or
flangedfitting.A flatsteel flangeisquotedasa flange whichismachinedflatanddoesnothave a
ridge-like elevatedface orringtype jointflange.The loose flatflange flatsurface allowsfull contact
betweenthe gasketandthe entire mattingsurface.
Flatface flangesshouldneverbe boltedontoanelevatedface flange.ASMEB31.1 states that the
elevatedface onthe carbonsteel flange mustbe removedwhenconnectingflatface castiron
flangestocarbon steel flangesandthata full face gasketisrequired.The flange face formrefersto
all applicationsinwhichcastironand otherbrittle materialsare usedtoproduce equipmentand
valves.For“FlatFace” flangesonlyFull Face Gasketsare tobe used.Thisensuresthatthe two
matingflangesare infull andequal contact.
RaisedFace Flanges
The RaisedFace flange isthe mostcommontype usedinprocessplantapplications,andcanbe
easilyidentified.Itiscalledanupliftedface becausethe surfacesof the gasketare raisedabove the
face of the boltingcircle.Forall forgedsteel flangeslike machineryandvalves,thisformof flange
maskis commonlyused.A wide combinationof gasketdesignscanbe usedinthe Raisedface
flanges.These combinationscanalsoinclude Flatringsheetsandspiral woundanddouble jacketed
type’smetalliccomponents.
The RaisedFace Flangesare usedto concentrate more pressure ona smallerareaof the gasketand
thusincrease the joint’spressure containmentcapability.The Boltholesare foundinthe outerring
regionforthose flanges.The “Move”adjustmentbetweenthe heightsof the tworingshelpsgreater
force to be appliedtothe gasketregion,therebycreatingastrongerseal whenagasketisattached
and the boltsare mountedandtorqued.Basedonthe pressure class,the flange face iseither1/16″
or 1/4″ ANSI300 and underhave a 1/16″ face raised,andANSI400 and higherhave a 1/4″ face
raised.
Ringjointflanges(RTJ)
Ring jointflanges(RTJ) have grooveswhichcutthe steel ringgasketsintotheirfaces.Whenbent
boltspushinthe groovesthe gasketbetweenthe flanges,the flangesclose (orcoin) the gasketand
create intimate contactwithinthe grooves,creatingametal tometal bond.Usuallythe RingStyle
Jointflangesare usedinsystemsover427 ° C withextreme pressure andhightemperature.AnRTJ
flange witharing groove machined intoitmayhave an elevatedface.The face raiseddoesnotactas
any componentof the meansof sealing.The elevatedfacesof the attachedandtightenedflanges
may touchone anotherfor RTJ flangeswhichseal withringgaskets.
6. For thisto occur, the ring jointgasketmaterial mustbe weaker(more ductile) thanthe flange
material.The strainedgasketwillnotbe able towithstandadditional loadinthiscase beyondthe
tensionof the screw,vibrationandmotioncannotfurthercrackthe gasketandreduce the
connectionvoltage.The Rtype withanoctagonal portionisthe mostcommonRTJ gasket,as it
guaranteesanextremelystrongseal.Nonetheless,a“simple groove”style recognizesthatbothRTJ
gasketshave an octagonal or oval portion.
Groove & Tongue Flanges
The Groove and Tongue flangeshave tosuitthe Tongue andGroove ears.One side of a flange hasa
raisedring(Tongue) machinedontothe face of the flange whilethe matingflange hasa
correspondingdepression(Groove) machinedinitsnose.Both large andsmall typesof tongue-and-
groove facingsare standardized.These varyfrommale-and-femaleinthatthe tongue-and-groove
internal diametersdonotreachinto the base of the flange,therebyholdingthe gasketonitsinner
and outerdiameter.These are commonlyfoundonValve Bonnetsandonpumpcoverings.
Tongue-and-groove jointsalsohave abenefitinthattheyare self-alignedandserve asanelastic
buffer.The scarf jointholdsthe loadingpointinline withthe jointanddoesnotrequire an intensive
machiningprocess.Specificflangefaceslike the RTJ,Tand G, and F and Mare not to be bolted.This
isbecause the touch surfacesdonot overlapandthere isnogasketwhichhas one type on one hand
and anothertype onthe other.Groove & Tongue flangesare usedinlow pressure,non-critical
applications,toattachotherGroove & Tongue components.
Male & Female Flanges
Male & Female Flangesare akindof flange thatwantsto fitone another.One flange face inthese
variationshasa regionwhichstretchesbeyondthe usual flange face.ThisflangeisnamedThe Man.
The matingflange or the otherflange,onthe otherside,will have asimilardepressionmachined
intoitsnose.Thismatingflange iscalledthe Womanflange
The flangesmustbe alignedwiththisformtoo.Each facial flange hasa regionthatstretchesbeyond
the normal face of the flange (Male).The otherflange or matingflange hasa corresponding
depression(Female)machinedintothe face of it.
The female facesare supposedtobe 3/16-inch long,the male face are supposedtobe 1/4-inch wide
and eachendflat.The female face’sexteriordiameterservestofindand maintainthe gauze.There
are infact 2 versions;the MediumM&FFlangesandthe Wide M&F Flanges.
Male andfemale flangeshave improvedsealingabilities,more reliablepositioningandspecific
compressionof sealingmaterial,use of other,more effectivesealingmaterialandadvancedsealing
material (O-rings).
DifferentTypesof InternationalStandardforflanges:
ASME B16.5 Flanges
The ASME B16.5 standard coversNPS1/2 throughNPS24 Metric / Inchsteel pipe flangesand
flangedfittingsinpressure class150 to class2500. Thisincludeslevelsof pressure-temperature,
components,lengths,tolerances,naming,measuringandmethodsof designatingopeningsfor
flangedfittingsandpipe flanges.Forpipingstructurestwoverycritical flangessuchasweld neck
flange andblindflangesare widelyused.Interchangeabilityisusedforthe word“B16.5” or “B16 5,”
whichcorrespondstothe same norm. The regularASME B16 5 (ANSIB16 5), though,onlyincludes
measurementsupto24 inches.
7. The current standardand the correct one is ASME B16.5. ANSIB16.5 iscommonin the lingo
industry,andisstill widelyusedbyarchitects,engineers,manufacturersandsuppliers.Eventhough
the ANSIB16.5 standardsdoesnot existtechnically,itwasunderstoodasa differentwayof saying
ASME B16.5.
ANSIB16.47 Flanges
ANSIB16.47 (Large DiameterSteel Flanges) isastandardforthe flangesof steel pipesNPS26to NPS
60 in diameter.Nevertheless,the regularANSIB16.47 isfurthersplitintoBlindFlange andANSI
B16.47 SeriesA andANSIB16.47 B flange Weldneckflange.The API605 flange wasformerlyalso
knownas the SeriesBflange.TermsB16.47 or B 16 47 or ANSIB 16 47 are interchangeableand
conformto the same standard.
The latestversionprovidesbothmetricandinchmeasurementsandscoresinunits.MSSSP-44:Steel
Pipeline FlangesandAPI605: The ANSIB16.47 is fittedwithlarge diameterCarbonSteel Flanges.
Thus,the MSS SP-44 flangesare referredtoasANSIB16.47 SeriesA flanges,whereaswithinthis
standardthe API605 flangesare referredtoas ANSIB16.47 SeriesBflanges.The ANSIB16.47
standardcontainsthe requirementsforpressure-temperature,parts,dimensions,tolerances,
markingand examinationof pipe flangesinsizesNPS26to NPS60 and inclassificationgrades75,
150, 300, 400, 600 and900 for largersizes.
BS 10 Flanges
The BritishStandardBS10, 1962 is the standardcylinders,tubes,andfittingsflangesandbolting
design.Inmm, the BS 10 flange sizescomprise boss,simple,integrallycast oretched,andneck
weldingstyleflanges,inflangesasperBS10 Tables.Althoughthe BS10 table of pipe flangesis
obsolescent,the BS10 flange chartfor lightdutyspans,inexpensive stainlesssteel flanges,isstill in
use.These BS10 type flangescouldbe made fromheavymetalsandalloyslike stainlesssteel,
carbon steels,alloyslikeelementsincludingnickel,copperetc.
BS 10 flangesare recognizedforboththeirreliabilityandexcellentperformance,makingthemone
of the mostcost-effective solutionsavailable.The BS10 neck flangeshave goodperformance bothin
hightemperature conditionsandhighpressure.The BS10 table d flangesmayalsobe made from
gradessuch as duplex andSuperduplexstainlesssteel,basedonthe enduse of the component.
DIN Flanges
The GermanInstitutionforStandardization’sDeutschesInstitutfürNormung(DIN) isthe German
national standardizationorganization,andisthe Official ISOaffiliate body.DIN FlangesisaBerlin-
based,GermanRegisteredAssociation’sdesignationsforthe divisionflanges.Currentlythere are
aroundthirtythousandDIN standards,coveringalmosteverytechnologyarea.DIN Flangesare most
commonlyspecifiedinEuropeancountries.
DIN standardFlangesuse metricmeasurements(mmandbar) to measure the valve andflange sizes
and pressures.EuropeanfirmstypicallyemployDIN standardforflanges,evenif manufacturing
occurs inthe UnitedStates.DIN Flangeshave awide reach,andover30,000 DIN standardsof flange
provide comprehensive coverageforvariousproductsof Flange typesandtechnologies.The DIN
specificationof flangesconsistof DIN Numbersstartingfrom15,20, 25, 32, 40, 50, 65, 80 and soon
up to 200.
EN 1092-1 Flanges
8. EN 1092-1 is an Extensionof the BritishStandard of Specification.Thissupersedesthe discontinued
BS EN 1092-1. InEN 1092-1 of BS. A Europeanmetricrange comprisingCircularflangessizesvarying
fromDN size 10 to 4000 and 2, 5 and 100 PN designations.ThisEUstandarddefinesspecifications
for circularsteel flangesfromDN 10 to DN 4000 in PN designationsPN 2,5 to PN 400, and nominal
measurements.
The specificationdefinesthe formsof flange anditsfacings,lengths,tolerances,threading,bolt
sizes,surface texture,labeling,fabrics,pressure /temperaturelevels,andflange weights.EN 1092-1
Form 01 pn10 Flange isdepositedorusable forthe crude,coal,petrochemical andrelatedindustries
inthe followingvarietyof materialsandsizes;The componentsusedtoproduce the EN 1092-1
flangesare carbonsteel:A105, SS400, SF440, RST37.2, S235JRG2, P250GH, C22.8. These are also
producedfromStainlessSteel Grades:F304 F304L F316 F316L 316Ti, and so on.
BS 4504 Flanges
BS 4504 Flangescome undera Britishmetricscale thatincludescircular flangesbetweenPN 2.5and
PN 40 forcylinders,valvesandfittings,includingflangesof DN measurements.Before thatitwas
knownas BS 4504: 1969. These flangesare ideal foruse understrictconditions,especiallyforlow-
pressure applicationsinthe oil sector.A EuropeanmetricstandardcoveringCircularflanges
specificationsrangesfromDN size 10 to 4000 and 2, 5 and 100 PN designations.
The BS 4504 FlangesconsistflangesstandardsANSIB16.5,ANSIB16.47, ANSIB16.36. Theyalso
consistDIN numberslike DIN2527, DIN2566, DIN2573, DIN2576, DIN2641, DIN2642. These BS 4504
Flangesare foundinapplicationsinindustriessuchasChemicalsFertilizersIndustries,Heat
Exchangerindustries,InstrumentationindustriesandNuclearThermal Industries.
JISStandard Flanges
The JISstandardsare Japanese IndustrialStandardsthatare usedfor the industrial activitiesin
Japan.Thiswas coordinatedbyJapanese Industrial Standscommittee (JISC).The JapanStandards
Association(JSA)waspreviouslyattachedto METI,whichis now an autonomousfoundation.This
has a broad varietyof programsregardingJapanese andforeignstandardsinmind.The JISStandard
Flangescome underJIS-Bdivisionandtheyare classifieduponthe differentdimensionstheyare
made in.
These Japanese Industrial StandardFlangestypesare categorizedintodivisionssuchasJIS5k,JIS10K,
JIS15K, JIS20K.The JISB2200 K Flangesare definedbyreplacingthe Kwithone of the above
mentionedcategoriessuchas5K, 10K, 15K, and 20K. The Dimensionsof eachflangesdependsupon
the categoriesortypesof flanges.
MaterialsusedtoManufacture Flanges:
These Steel flangesare manufacturedfromdifferentmaterialssuchasCarbonsteel,Low alloysteel,
StainlessSteel Flanges,Duplex Steel Flanges,SuperDuplex Steel Flanges,Monel Flanges,Inconel
Flanges,HastelloyFlanges,Nickel FlangesandCombinationof Exoticmaterials(Stub) andother
backingmaterials.
• CarbonSteel:– ASTMA105, ASTMA350 LF1/2, ASTMA181
• AlloySteel:–ASTMA182F1 /F2 /F5 /F7 /F9 /F11 /F12 /F22
• StainlessSteel: –ASTMA182F6 /F304 /F304L /F316 /F316L/ F321/F347/F348
• Duplex Steel S31803 / S32205
