1、AN AMERICAN NATIONAL STANDARDASME B16.21-2011(Revision of ASME B16.21-2005)Nonmetallic Flat Gaskets forPipe FlangesINTENTIONALLY LEFT BLANKASME B16.21-2011(Revision of ASME B16.21-2005)Nonmetallic FlatGaskets forPipe FlangesAN AMERICAN NATIONAL STANDARDThree Park Avenue New York, NY 10016 USADate of
2、 Issuance: February 23, 2011The next edition of this Standard is scheduled for publication in 2016. This Standard will becomeeffective 6 months after the Date of Issuance. There will be no addenda issued to this edition.ASME issues written replies to inquiries concerning interpretations of technical
3、 aspects of thisStandard. Interpretations are published on the ASME Web site under the Committee Pages athttp:/cstools.asme.org as they are issued.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeti
4、ng the criteria for American NationalStandards. The Standards Committee that approved the code or standard was balanced to assure that individuals fromcompetent and concerned interests have had an opportunity to participate. The proposed code or standard was madeavailable for public review and comme
5、nt that provides an opportunity for additional public input from industry, academia,regulatory agencies, and the public-at-large.ASME does not “approve,” “rate,” or “endorse” any item, construction, proprietary device, or activity.ASME does not take any position with respect to the validity of any p
6、atent rights asserted in connection with anyitems mentioned in this document, and does not undertake to insure anyone utilizing a standard against liability forinfringement of any applicable letters patent, nor assumes any such liability. Users of a code or standard are expresslyadvised that determi
7、nation of the validity of any such patent rights, and the risk of infringement of such rights, isentirely their own responsibility.Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted asgovernment or industry endorsement of this code or sta
8、ndard.ASME accepts responsibility for only those interpretations of this document issued in accordance with the establishedASME procedures and policies, which precludes the issuance of interpretations by individuals.No part of this document may be reproduced in any form,in an electronic retrieval sy
9、stem or otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2011 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword ivCommittee Roster . vCorres
10、pondence With the B16 Committee viSummary of Changes vii1 Scope 12 General. 13 Materials . 14 Dimensions and Tolerances 15 Markings . 2Tables1 Gasket Dimensions for ASME B16.1 Class 25, Cast Iron Pipe Flanges and FlangedFittings . 32 Gasket Dimensions for ASME B16.1 Class 125, Cast Iron Pipe Flanges
11、 and FlangedFittings . 43 Flat Ring Gasket Dimensions for ASME B16.1 Class 250, Cast Iron Pipe Flanges andFlanged Fittings . 54 Gasket Dimensions for ASME B16.5 Class 150, Pipe Flanges and FlangedFittings . 55 Flat Ring Gasket Dimensions for ASME B16.5, Pipe Flanges and Flanged Fittings,Classes 300,
12、 400, 600, and 900 66 Full Face Gasket Dimensions for ASME B16.24, Cast Copper Alloy Pipe Flangesand Flanged Fittings, Classes 150 and 300 67 Flat Ring Gasket Dimensions for ASME B16.47 Series A, Large Diameter SteelFlanges, Classes 150, 300, 400, and 600 . 78 Flat Ring Gasket Dimensions for ASME B1
13、6.47 Series B, Large Diameter SteelFlanges, Classes 75, 150, 300, 400, and 600 79 Full Face Gasket Dimensions for MSS SP-51 Class 150LW, Corrosion-ResistantCast Flanges and Flanged Fittings . 8Mandatory AppendicesI Dimensions of Gaskets in U.S. Customary Units 9II References . 14Nonmandatory Appendi
14、cesA Quality System Program . 15B References . 16iiiFOREWORDBefore this Standard was issued, the individual sizes of gaskets were made to many differentsets of dimensions, based on different concepts of adaptation and functional use on the part ofconsumers as well as manufacturers. In some cases, di
15、mensions were shown in AmericanStandards. To standardize gasket sizes, the Standards and Specifications Committee of theMechanical Packing Association (MPA) started work on a standard for nonmetallic or cut gasketsfor bronze, iron, and steel pipe flanges.Dimensions of gaskets being used were collect
16、ed, and a basic design philosophy for sizingwas formulated by the Committee. This was the result of extensive field research experience andaccepted standard user requirements. The procedure that followed was to dimension the gasketfor each type and size of flange so as to prevent the gasket from pro
17、jecting into the line of flow.Dimensional tolerances of standard pipe flanges and fittings as to I.D., O.D., and bolting wereall considered.Suggested dimensional standards were tabulated and distributed for industry comment. Afterseveral revisions, a final draft, dated September 15, 1948, was approv
18、ed by the MPA for submissionas an American Standard.Sectional Committee (B16) on the Standardization of Pipe Flanges and Fittings was organizedin 1921 under the procedure of the American Standards Association (ASA), with the Heating,Piping, and Air Conditioning Contractors National Association now M
19、echanical ContractorsAssociation of America (MCAA), Manufacturers Standardization Society of the Valve andFittings Industry (MSS), and the American Society of Mechanical Engineers (ASME) as jointsponsors.Sectional Committee B16 received the proposal on May 9, 1949, and assigned it to a joint groupof
20、 Subcommittees 1 and 3. The MSS was also consulted as the proposal included gaskets forbronze flanges made to their Standard Practice SP-2. This joint group offered a revision of theoriginal design concept for sizing, which was acceptable to the MPAs Committee now the FluidSealing Association (FSA).
21、 The Standard was approved as an American Standard on December5, 1951, with the designation ASA B16.21-1951.In 1961, the Standard was reviewed by the members of Subcommittee No. 7 on Gaskets andproposals for revision and updating the Standard were agreed upon. The ASA granted approvalof the revision
22、 on March 20, 1962 following sectional committee and sponsor approval.In the mid-1960s, work had begun on a revision. The revision became a complete rewrite andincluded gaskets for API Std 605, MSS SP-44 and SP-51, as well as complete metric equivalentsfor all dimensions. Following its approval by t
23、he B16 Standards Committee and Co-Secretariatorganizations, this Standard was approved as an American National Standard by AmericanNational Standards Insitute (ANSI) on May 2, 1978.In 1982, American National Standards Committee B16 was reorganized as an ASME Committeeoperating under procedures accre
24、dited by ANSI.In 1989, general revisions had begun to reflect the current size ranges covered by the correspond-ing flange standard. Gasket dimensions for tongue and groove, male and female Rating Classesabove 900 were deleted because a survey indicated these nonmetallic gaskets were almost neveruse
25、d for these joints. Tolerances to the dimensions were added.Following approval by the Standards Committee and ASME, approval as an American NationalStandard was given by ANSI on March 16, 1992, with the new designation ASME B16.21-1992.In 2005, the Standard adopted metric (SI) dimensions. Following
26、approval by theB16 Subcommittee G, the B16 Standards Committee, and ASME, ANSI approved this AmericanNational Standard on March 16, 2005.The 2011 edition includes revisions to paragraph numbering and adjustments of appendices.All requests for interpretation or suggestions for revisions should be sen
27、t to The AmericanSociety of Mechanical Engineers, Attn: Secretary, B16 Standards Committee, Three Park Avenue,New York, NY 10016-5990.The B16 Committee operates under procedures accredited by ANSI. Following approval bythe Standards Committee and ASME, this revision to the 2005 edition was approved
28、as anAmerican National Standard by ANSI on January 13, 2011 with the designation ASME B16.21-2011.ivASME B16 COMMITTEEStandardization of Valves, Flanges, Fittings, and Gaskets(The following is the roster of the Committee at the time of approval of this Standard.)STANDARDS COMMITTEE OFFICERSW. B. Bed
29、esem, ChairG. A. Jolly, Vice ChairD. R. Sharp, SecretarySTANDARDS COMMITTEE PERSONNELR. W. Barnes, Anric Enterprises, Inc.W. B. Bedesem, ConsultantD. F. Buccicone, Elkhart Products Corp.A. M. Cheta, Royal Dutch ShellM. A. Clark, NIBCO, Inc.G. A. Cuccio, Capitol Manufacturing Co.C. E. Davila, Crane E
30、nergy Flow SolutionsD. R. Frikken, Becht Engineering Co.R. P. Griffiths, U.S. Coast GuardG. A. Jolly, Vogt Valves/Flowserve Corp.SUBCOMMITTEE G GASKETS FOR FLANGED JOINTSW. M. Stephan, Chair, Flexitallic L.P.C. B. Gillis, Vice Chair, Teadit North AmericaR. J. Horvath, Secretary, The American Society
31、 of MechanicalEngineersK. A. Benton, ConsultantR. A. Bojarczuk, ExxonMobil Research however, they shouldnot contain proprietary names or information.Requests that are not in this format will be rewritten in this format by the Committee priorto being answered, which may inadvertently change the inten
32、t of the original request.ASME procedures provide for reconsideration of any interpretation when or if additionalinformation that might affect an interpretation is available. Further, persons aggrieved by aninterpretation may appeal to the cognizant ASME Committee or Subcommittee. ASME does not“appr
33、ove,” “certify,” “rate,” or “endorse” any item, construction, proprietary device, or activity.Attending Committee Meetings. The B16 Standards Committee regularly holds meetings, whichare open to the public. Persons wishing to attend any meeting should contact the Secretary ofthe B16 Standards Commit
34、tee.viASME B16.21-2011SUMMARY OF CHANGESFollowing approval by the ASME B16 Standards Committee and ASME, and after public review,ASME B16.21-2011 was approved by the American National Standards Institute on January13, 2011.ASME B16.21-2011 includes editorial changes, revisions, and corrections intro
35、duced inASME B16.21-2005, as well as the following changes identified by a margin note, (11), placednext to the affected area.Page Location Change1 1 Revised and redesignated1 2 Revised and redesignated14 Mandatory Appendix II Revised15 Nonmandatory Footnote revisedAppendix A16 Nonmandatory Appendix
36、 B AddedviiINTENTIONALLY LEFT BLANKviii(11)(11)ASME B16.21-2011NONMETALLIC FLAT GASKETS FOR PIPE FLANGES1 SCOPEThis Standard covers types, sizes, materials, dimen-sions, tolerances, and markings for nonmetallic flat gas-kets. These gaskets are dimensionally suitable for usewith flanges described in
37、the referenced flangestandards.2 GENERAL2.1 Relevant UnitsThis Standard states values both in SI (metric) andU.S. Customary units. As an exception, diameter of boltsand flange bolt holes are expressed in inch units only.These systems of units are to be regarded separately asstandard. Within the text
38、, the U.S. Customary units areshown in parentheses or in separate tables. The valuesstated in each system are not exact equivalents; therefore,it is required that each system of units be used indepen-dently of the other. Except for diameter of bolts andflange bolt holes, combining values from the tw
39、o sys-tems constitutes nonconformance with the Standard.2.2 Quality SystemsRequirements relating to the product manufacturersquality system programs are described inNonmandatory Appendix A.2.3 ReferencesStandards and specifications adopted by reference inthis Standard are shown in Mandatory Appendix
40、 II.2.4 Flanged JointsA flanged joint is composed of separate and indepen-dent, although interrelated, components: the flanges,gasket, and bolting, which are assembled by anotherinfluence, the assembler. Proper controls must be exer-cised in the selection and application for all these ele-ments to a
41、ttain a joint that has acceptable leak tightness.Additional guidelines for flange assembly can be foundin ASME PCC-1 (see Nonmandatory Appendix B).2.5 TypesDimensions are provided for the following types ofgaskets, which are suitable for use with the flange facesindicated:Gasket Type Flange FacingFu
42、ll face Flat faceFlat ring Raised face12.6 SizeNPS, followed by a dimensionless number, is the des-ignation for nominal pipe size, as described inASME B36.10M and is related to the reference nominaldiameter, DN, used in international standards. The rela-tionship is as follows:NPS DN12153420125114321
43、12402502126538312904 100GENERAL NOTE: For NPS 4, the related DN p 25 H11547 NPS2.7 Pressure Class DesignationClass, followed by a dimensionless number, is thedesignation for common flange pressure-temperatureratings as given by the referenced flange standards.3 MATERIALS3.1 CompositionGaskets shall
44、be made of resilient or pliable materials.Metal or nonmetal composites may be incorporated asreinforcement or filler material.3.2 Service RequirementsSelection of a material suitable for a given serviceapplication is the responsibility of the user subject tothe requirements of any applicable code or
45、 governmentregulation. The material selected shall be compatiblewith the fluid and suitable for the pressure-temperatureconditions of the service.4 DIMENSIONS AND TOLERANCES4.1 DimensionsGasket dimensions shall be in accordance withTables 1 through 9 (Tables I-1 through I-9 of MandatoryAppendix I) f
46、or the flanges standards, sizes, and classesindicated. Selection of gasket thickness is the responsi-bility of the user, considering the properties of the gasketmaterial as well as the intended service application.ASME B16.21-20114.2 Tolerances(a) Outside diameter for(1) NPS 12 and smaller:+0.0, 1.5
47、 mm (+0.0, 0.06 in.)(2) NPS 14 and larger:+0.0, 3.0 mm (+0.0, 0.12 in.)(b) Inside diameter for(1) NPS 12 and smaller, 1.5 mm (0.06 in.)(2) NPS 14 and larger, 3.0 mm (0.12 in.)(3) bolt circle diameter, 1.5 mm (0.06 in.)2(4) center to center of adjacent bolt holes, 1.0 mm(0.03 in.)5 MARKINGS5.1 Materi
48、al MarkingUnless otherwise specified by the purchaser, gasketmaterial shall be marked with the material manufactur-ers name or trademark and material designation.5.2 Gasket MarkingGaskets shall be packaged with NPS, class, gasketmanufacturers name, material designation, thickness,and ASME B16.21 mar
49、ked or tagged on the packageor gasket. At the option of the manufacturer, the DNdesignation may be included.ASME B16.21-2011Table 1 Gasket Dimensions for ASME B16.1 Class 25, Cast Iron Pipe Flanges and Flanged FittingsFull Face GasketNPS Gasket I.D. Flat Ring O.D. O.D. Number of Holes Hole Diameter Bolt Circle Diameter4 114 175 229 834190.55 141 200 254 834215.96 168 225 279 834241.38 219 283 343 834298.510 273 346 406 1234362.012 324 416 483 1234431.814 356 457 533 1278476.316 406 521 597 1678539.818 457 559 635 1678577.920 508 616 699 2078635
