ASTM_E_2734_-_E_2734M_-_10.pdf

Designation:E2734/E2734M10Standard Specification forDimensions of Knife-Edge Flanges1This standard is issued under the fixed designation E2734/E2734M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This standard specifies the dimensions of knife-edgestyle flanges and their associated gaskets used in vacuumsystems for pressures ranging from 105Pa to 10-11Pa.Suchflanges are widely used throughout vacuum technology appli-cations in semiconductor processing tools,surface analysissystems,space simulation systems,and general research re-quiring vacuum.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E673 Terminology Relating to Surface Analysis(Withdrawn2012)32.2 Other Standards:4ISO 4288:1996 Geometrical Product Specifications(GPS)Surface Texture:Profile MethodRules and Proceduresfor the Assessment of Surface Texture3.Terminology3.1 Definitions For definitions used in this specification,see Terminology E673.3.2 Definitions of Terms Specific to This Standard:3.2.1 knife-edge flange,nVacuum flanges seal with ametal gasket;two mating surfaces with identical circular(triangular profile)knife-edges are bolted together;a deform-able metal gasket,captured between the knife-edges provides aleak-free seal.3.2.1.1 DiscussionVacuum flanges that seal with a metalgasket were originally developed as Conflat flanges(trade-mark)by the Varian Corporation.3.2.2 type,nKnife-edge flanges come in a variety of sizes;historically,the flange sizes were identified in North Americaas the flanges outside diameter(in inches)and in Europe as themaximum nominal bore of the tube(in millimetres)that mightbe welded to the flange;for this specification,the flangeidentification“type”is used where the type is approximatelyequal to the flanges outside diameter in inches.4.Materials and Manufacture4.1 FlangeFlanges must be manufactured from a suffi-ciently hard or hard-coated material to resist deformation of theknife-edge profile despite repeatedly forming a vacuum sealwith metal gaskets.4.2 GasketGasket must be manufactured from a soft,annealed,or partially-tempered metal such that the matingflanges knife-edges cause sufficient(initial)plastic deforma-tion that a vacuum seal is accomplished.5.Dimensions,Mass,and Permissible Variations5.1 Figs.1-3 and Tables 1 and 2 contain the requireddimensions and tolerances for rotatable and non-rotatableknife-edge vacuum flanges.6.Workmanship,Finish,and Appearance6.1 Knife-edge vacuum flanges are typically used in appli-cations which require:(1)a high degree of leak integrity,and(2)the lowest possible contamination from outgassing.Toachieve both characteristics,the finish of the flanges knife-edges and gaskets must be free of visible cracks,pits,inclusions,scratches,and foreign materials.The knife-edge1This specification is under the jurisdiction ofASTM Committee E42 on SurfaceAnalysis and is the direct responsibility of Subcommittee E42.13 on VacuumTechnology.Current edition approved Jan.1,2010.Published May 2010.DOI:10.1520/E2734_E2734M-10.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from International Organization for Standardization(ISO),1,ch.dela Voie-Creuse,Case postale 56,CH-1211,Geneva 20,Switzerland,http:/www.iso.ch.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 FIG.1 Flange Dimensions:(a)Non-Rotatable Flange(b)Rotatable FlangeFIG.2 Knife-Edge DetailFIG.3 Knife-Edge Gasket DimensionsE2734/E2734M 102 TABLE 1 Knife-Edge Flange DimensionABCDEFGHITypeNominalBoreNominalOutsideDiameterTolerance0.030 in.(0.75 mm)MaxTubeDiameterNum-berofBoltHolesBoltHoleDiameterBoltThreadBoltCirclePositionToleranceofBoltHolesSealRecessDiameterTolerance0.004 in.(0.10 mm)KnifeEdgeDiameterTolerance0.004 in.(0.10 mm)SetbackFlangeFace toTube SeatTolerance0.005 in.(0.12 mm)Depth ofReceiverSeat forInsert(Max)FlangeThickness(Min)mmin.mmin.Min,mmMax,mmMin,in.Max,in.mmin