1、Buttwelding EndsA N A M E R I C A N N A T I O N A L S T A N D A R DASME B16.25-2007(Revision of ASME B16.25-2003)Copyright ASME International Provided by IHS under license with ASME Licensee=CSA Toronto/5934117001,User=liu,ericNot for Resale,09/27/2008 18:26:53 MDT No reproduction or networking perm
2、itted without license from IHS-,-,-ASME B16.25-2007(Revision of ASME B16.25-2003)ButtweldingEndsAN AMERICAN NATIONAL STANDARDThree Park Avenue New York,NY 10016Copyright ASME International Provided by IHS under license with ASME Licensee=CSA Toronto/5934117001,User=liu,ericNot for Resale,09/27/2008
3、18:26:53 MDT No reproduction or networking permitted without license from IHS-,-,-Date of Issuance:March 7,2008The next edition of this Standard is scheduled for publication in 2012.There will be no addendaissued to this edition.ASME issues written replies to inquiries concerning interpretations of
4、technical 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
5、as meeting 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
6、 comment 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 paten
7、t 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 assume any such liability.Users of a code or standard are expresslyadvised that determination o
8、f 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 standard.ASME a
9、ccepts 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 system or other
10、wise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue,New York,NY 10016-5990Copyright 2008 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.Copyright ASME International Provided by IHS under license w
11、ith ASME Licensee=CSA Toronto/5934117001,User=liu,ericNot for Resale,09/27/2008 18:26:53 MDT No reproduction or networking permitted without license from IHS-,-,-CONTENTSForeword.ivCommittee Roster.vCorrespondence With the B16 Committee.vi1 Scope.12 Transition Contours.13 Welding Bevel Design.14 Pre
12、paration of Inside Diameter of Welding End.25 Tolerances.3Figures1 Maximum Envelope for Welding End Transitions.42 Bevels for Wall Thickness Over 3 mm(0.12 in.)to 22 mm(0.88 in.),Inclusive.53 Weld Bevel Details for Wall Thickness Over 22 mm(0.88 in.).64 Weld Bevel Details for GTAW Root Pass Wall Thi
13、ckness Over3 mm(0.12 in.)to 10 mm(0.38 in.),Inclusive.75 Weld Bevel Details for GTAW Root Pass Wall Thickness Over10 mm(0.38 in.)to 25 mm(1.0 in.),Inclusive.76 Weld Bevel Details for GTAW Root Pass Wall Thickness Over25 mm(1.0 in.).8Ta b l e1 Dimensions of Welding Ends.9Mandatory AppendicesI Inch Ta
14、ble.13II References.18Nonmandatory AppendixA Quality System Program.19iiiCopyright ASME International Provided by IHS under license with ASME Licensee=CSA Toronto/5934117001,User=liu,ericNot for Resale,09/27/2008 18:26:53 MDT No reproduction or networking permitted without license from IHS-,-,-FOREW
15、ORDIn July 1953,the American Welding Society presented a proposal on Welding End Preparationto Sectional Committee B16 of the American Standards Association(ASA),with the recommenda-tion that it be considered as a candidate for an American Standard.The proposal was expandedto include welding prepara
16、tion for flanges and valves covered by ASA B16.5,Steel Pipe Flangesand Flanged Fittings,and for fittings covered by ASA B16.9,Buttwelding Fittings.Considerationwas also given to Pipe Fabrication Institute Standard ES-1.The third draft reviewed by Subcommittee 3,Subgroup 6(now Subcommittee F)of theB1
17、6 Sectional Committee was forwarded to the Committee,to the cosponsor organizations,andthen to ASA for approval.Final approval was given on September 14,1955,with the designationASA B16.25-1955.Revisions were developed as a need for clarification and improvements became known,andwere approved as ASA
18、 B16.25-1958 and ASA B16.25-1964.After ASA reorganized as the AmericanNational Standards Institute(ANSI)and the Sectional Committee became American NationalStandards Committee B16,a further revision was approved as ANSI B16.25-1972.Subcommittee F immediately began work on a major expansion and updat
19、ing of the standard,adding illustrations and requirements for welding end configurations applicable to a number ofspecific circumstances,including cast steel and alloy valves.When a draft had been developed thatovercame the many problems and conflicting demands,the Standards Committee,cosecretariato
20、rganizations,and ANSI concurred in approval of ANSI B16.25-1979 on July 18,1979.In 1982,American National Standards Committee B16 was reorganized as an ASME committeeoperating under procedures accredited by ANSI.In the 1986 edition,inch dimensions wereestablished as the standard and numerous changes
21、 in text and format were made.Notes forillustrations were also clarified.Following approval by the Standards Committee and ASME,approval as an American National Standard was given by ANSI on October 8,1986,with thenew designation ASME/ANSI B16.25-1986.In 1992,the subcommittee revised the requirement
22、s for the preparation of the inside diameterof welding end.The references in Annex B were also updated.After public review and approvalby ASME,this edition was approved by ANSI on October 26,1992,with the new designationASME B16.25-1992.In the 1997 edition,metric dimensions were added as an independ
23、ent but equal standard tothe inch units.An Annex was also added to reference quality system requirements.Followingapproval by the Standards Committee and ASME,this revision to the 1992 edition of B16.25 wasapproved as an American National Standard by ANSI on April 17,1997 with the new designationASM
24、E B16.25-1997.In the 2003 edition,the reference standard dates were updated.There were clarifications totext made to address inquiries.Tolerances on bevel angles were modified slightly.Followingapproval by the Standards Committee and ASME,this revision to the 1997 edition of B16.25 wasapproved as an
25、 American National Standard by ANSI on December 17,2003,with the newdesignation ASME B16.25-2003.In this 2007 edition,buttwelding end data has been extended to cover requirements for sizesup to NPS 48(DN 1200).The reference data has been updated and the interpretation section hasbeen removed from th
26、e standard.This revision was approved as an by American National Standards Institute on August 17,2007.Requests for interpretation or suggestions for revision should be sent to the Secretary,B16Committee,The American Society of Mechanical Engineers,Three Park Avenue,New York,NY10016-5990.ivCopyright
27、 ASME International Provided by IHS under license with ASME Licensee=CSA Toronto/5934117001,User=liu,ericNot for Resale,09/27/2008 18:26:53 MDT No reproduction or networking permitted without license from IHS-,-,-ASME B16 COMMITTEEStandardization of Valves,Flanges,Fittings,and Gaskets(The following
28、is the roster of the Committee at the time of approval of this Standard.)STANDARDS COMMITTEE OFFICERSH.R.Sonderegger,ChairM.L.Nayyar,Vice ChairU.DUrso,SecretarySTANDARDS COMMITTEE PERSONNELR.W.Barnes,ANRIC EnterprisesW.B.Bedesem,ExxonMobil Research and Engineering Co.D.F.Buccicone,Elkhart Products C
29、orp.M.A.Clark,NIBCO,Inc.U.DUrso,American Society of Mechanical EngineersC.E.Floren,Mueller Co.D.R.Frikken,Becht Engineering Co.,Inc.A.Hamilton,ABS AmericasM.L.Henderson,ConsultantG.A.Jolly,Vogt Valves/Flowserve Corp.SUBCOMMITTEEFS TEEL-THREADED AND WELDING FITTINGSG.A.Jolly,Chair,Vogt Valves/Flowser
30、ve Corp.G.A.Cuccio,Vice Chair,Capitol Manufacturing Co.T.Lazar,Secretary,The American Society of Mechanical EngineersA.Appleton,Alloy Stainless Products Co.,Inc.W.J.Birkholz,Markovitz Enterprises,Inc.K.W.Doughty,Shaw Alloy Piping Products,Inc.J.P.Ellenberger,ConsultantD.R.Frikken,Becht Engineering C
31、o.,Inc.vM.Katcher,Haynes InternationalW.N.McLean,Newco ValvesT.A.McMahon,Fisher Controls International,Inc.M.L.Nayyar,Bechtel Power Corp.J.D.Page,U.S.Nuclear Regulatory CommissionW.H.Patrick,The Dow Chemical Co.R.A.Schmidt,Hackney Ladish,Inc.H.R.Sonderegger,Anvil International,Inc.W.M.Stephan,Flexit
32、allic L.P.D.A.Williams,Southern Company GenerationR.E.Johnson,ConsultantC.J.Lafferty,Pennsylvania Machine Works,Inc.D.H.Monroe,ConsultantR.A.Schmidt,Hackney Ladish,Inc.H.R.Sonderegger,Anvil International,Inc.J.P.Tucker,Flowserve Corp.M.M.Zaidi,Jacobs Engineering Group,Inc.Copyright ASME Internationa
33、l Provided by IHS under license with ASME Licensee=CSA Toronto/5934117001,User=liu,ericNot for Resale,09/27/2008 18:26:53 MDT No reproduction or networking permitted without license from IHS-,-,-CORRESPONDENCE WITH THE B16 COMMITTEEGeneral.ASME Standards are developed and maintained with the intent
34、to represent theconsensus of concerned interests.As such,users of this Standard may interact with the Committeeby requesting interpretations,proposing revisions,and attending Committee meetings.Corre-spondence should be addressed to:Secretary,B16 Standards CommitteeThe American Society of Mechanical
35、 EngineersThree Park AvenueNew York,NY 10016-5990As an alternative,inquiries may be submitted via e-mail to:SecretaryB16asme.org.Proposing Revisions.Revisions are made periodically to the Standard to incorporate changesthat appear necessary or desirable,as demonstrated by the experience gained from
36、the applicationof the Standard.Approved revisions will be published periodically.The Committee welcomes proposals for revisions to this Standard.Such proposals should beas specific as possible,citing the paragraph number(s),the proposed wording,and a detaileddescription of the reasons for the propos
37、al,including any pertinent documentation.Interpretations.Upon request,the B16 Committee will render an interpretation of any require-ment of the Standard.Interpretations can only be rendered in response to a written request sentto the Secretary of the B16 Standards Committee.The request for interpre
38、tation should be clear and unambiguous.It is further recommendedthat the inquirer submit his/her request in the following format:Subject:Cite the applicable paragraph number(s)and the topic of the inquiry.Edition:Cite the applicable edition of the Standard for which the interpretation isbeing reques
39、ted.Question:Phrase the question as a request for an interpretation of a specific requirementsuitable for general understanding and use,not as a request for an approvalof a proprietary design or situation.The inquirer may also include any plansor drawings,which are necessary to explain the question;
40、however,theyshould not 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 intent of the original request.ASME procedures provide for reconsideration of any interpret
41、ation 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“approve,”“certify,”“rate,”or“endorse”any item,construction,proprietary device,or activity.Att
42、ending 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 Committee.viCopyright ASME International Provided by IHS under license with ASME Licensee=CSA Toronto/5934
43、117001,User=liu,ericNot for Resale,09/27/2008 18:26:53 MDT No reproduction or networking permitted without license from IHS-,-,-ASME B16.25-2007BUTTWELDING ENDS1 SCOPE1.1 GeneralThis Standard covers the preparation of buttweldingends of piping components to be joined into a pipingsystem by welding.I
44、t includes requirements for weldingbevels,for external and internal shaping of heavy-wallcomponents,and for preparation of internal ends(including dimensions and tolerances).Coverageincludes preparation for joints with the following:(a)no backing rings(b)split or noncontinuous backing rings(c)solid
45、or continuous backing rings(d)consumable insert rings(e)gas tungsten arc welding(GTAW)of the root passDetails of preparation for any backing ring must bespecified when ordering the component.1.2 ApplicationThis Standard applies to any metallic materials forwhich a welding procedure can be satisfacto
46、rilyqualified,but does not prescribe specific welding pro-cesses or procedures.Unless otherwise specified by thepurchaser,it does not apply to welding ends conformingto ASME B16.5,B16.9,or B16.47.1.3 Standard UnitsThe values stated in either metric or inch units are tobe regarded separately as the s
47、tandard.Within the text,the inch units are shown in parentheses.The valuesstated in each system are not exact equivalents;therefore,each system must be used independently of the other.Combining values from the two systems may result innonconformance with this Standard.1.4 SizeNominal pipe size(NPS),
48、followed by a dimensionlessnumber,is the designation for nominal fitting size.NPSis related to the reference nominal diameter(DN)usedin international standards.The relationship is typicallyas follows:NPS DN1215342012 5114321124025 02126538 04 1001For NPS 4,the related DNp 25 NPS.1.5 Referenced Stand
49、ardsStandards and specifications adopted by reference inthis Standard are shown in Mandatory Appendix II,which is part of this Standard.It is not considered practi-cal to identify the specific edition of each standard andspecification in the individual references;instead,thespecific edition is ident
50、ified in Mandatory Appendix II.An end preparation made in conformance to thisStandard in all other respects will be considered to bein conformance to the standard even though the editionreference may be changed in a revision of this Standard.1.6 Quality SystemsNonmandatory requirements relating to t
