1、Buttwelding EndsAN AMERICAN NATIONAL STANDARDASME B16.25-2007(Revision of ASME B16.25-2003)Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME B16.25-2007(Revision of ASME B16.25-2003)Buttwelding
2、EndsAN AMERICAN NATIONAL STANDARDThree Park Avenue New York, NY 10016Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-Date of Issuance: March 7, 2008The next edition of this Standard is scheduled f
3、or publication in 2012. There will be no addendaissued to this edition.ASME issues written replies to inquiries concerning interpretations of technical aspects of thisStandard. Interpretations are published on the ASME Web site under the Committee Pages athttp:/cstools.asme.org as they are issued.AS
4、ME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeting the criteria for American NationalStandards. The Standards Committee that approved the code or standard was balanced to assure that individuals fr
5、omcompetent and concerned interests have had an opportunity to participate. The proposed code or standard was madeavailable for public review and comment that provides an opportunity for additional public input from industry, academia,regulatory agencies, and the public-at-large.ASME does not “appro
6、ve,” “rate,” or “endorse” any item, construction, proprietary device, or activity.ASME does not take any position with respect to the validity of any patent rights asserted in connection with anyitems mentioned in this document, and does not undertake to insure anyone utilizing a standard against li
7、ability forinfringement of any applicable letters patent, nor assume any such liability. Users of a code or standard are expresslyadvised that determination of the validity of any such patent rights, and the risk of infringement of such rights, isentirely their own responsibility.Participation by fe
8、deral agency representative(s) or person(s) affiliated with industry is not to be interpreted asgovernment or industry endorsement of this code or standard.ASME accepts responsibility for only those interpretations of this document issued in accordance with the establishedASME procedures and policie
9、s, 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 otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue, New York, NY 10
10、016-5990Copyright 2008 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-CONTENTSForeword ivCommittee Roster . vCorr
11、espondence With the B16 Committee vi1 Scope 12 Transition Contours . 13 Welding Bevel Design . 14 Preparation 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 W
12、eld Bevel Details for Wall Thickness Over 22 mm (0.88 in.) 64 Weld Bevel Details for GTAW Root Pass Wall Thickness 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 G
13、TAW Root Pass Wall Thickness Over25 mm (1.0 in.) 8Table1 Dimensions of Welding Ends . 9Mandatory AppendicesI Inch Table . 13II References . 18Nonmandatory AppendixA Quality System Program . 19iiiCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or net
14、working permitted without license from IHS-,-,-FOREWORDIn 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 Stand
15、ard. The proposal was expandedto include welding preparation 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 revie
16、wed by Subcommittee 3, Subgroup 6 (now Subcommittee F) of theB16 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
17、 clarification and improvements became known, andwere approved as ASA 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-
18、1972.Subcommittee F immediately began work on a major expansion and updating 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 m
19、any problems and conflicting demands, the Standards Committee, cosecretariatorganizations, 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
20、1986 edition, inch dimensions wereestablished as the standard and numerous changes 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 the
21、new designation ASME/ANSI B16.25-1986.In 1992, the subcommittee revised the requirements 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
22、 designationASME B16.25-1992.In the 1997 edition, metric dimensions were added as an independent 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 w
23、asapproved as an American National Standard by ANSI on April 17, 1997 with the new designationASME 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. Followingappro
24、val by the Standards Committee and ASME, this revision to the 1997 edition of B16.25 wasapproved as an 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 N
25、PS 48 (DN 1200). The reference data has been updated and the interpretation section hasbeen removed from the 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,
26、B16Committee, The American Society of Mechanical Engineers, Three Park Avenue, New York, NY10016-5990.ivCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME B16 COMMITTEEStandardization of Valves,
27、 Flanges, Fittings, and Gaskets(The following 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
28、Research and Engineering Co.D. F. Buccicone, Elkhart Products Corp.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.
29、SUBCOMMITTEEFSTEEL-THREADED AND WELDING FITTINGSG. A. Jolly, Chair, Vogt Valves/Flowserve 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
30、.K. W. Doughty, Shaw Alloy Piping Products, Inc.J. P. Ellenberger, ConsultantD. R. Frikken, Becht Engineering Co., 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 Com
31、missionW. H. Patrick, The Dow Chemical Co.R. A. Schmidt, Hackney Ladish, Inc.H. R. Sonderegger, Anvil International, Inc.W. M. Stephan, Flexitallic L.P.D. A. Williams, Southern Company GenerationR. E. Johnson, ConsultantC. J. Lafferty, Pennsylvania Machine Works, Inc.D. H. Monroe, ConsultantR. A. Sc
32、hmidt, Hackney Ladish, Inc.H. R. Sonderegger, Anvil International, Inc.J. P. Tucker, Flowserve Corp.M. M. Zaidi, Jacobs Engineering Group, Inc.Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-CORRE
33、SPONDENCE WITH THE B16 COMMITTEEGeneral. ASME Standards are developed and maintained with the intent 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.
34、Corre-spondence should be addressed to:Secretary, B16 Standards CommitteeThe American Society of Mechanical 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 S
35、tandard to incorporate changesthat appear necessary or desirable, as demonstrated by the experience gained from 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 po
36、ssible, citing the paragraph number(s), the proposed wording, and a detaileddescription of the reasons for the proposal, including any pertinent documentation.Interpretations. Upon request, the B16 Committee will render an interpretation of any require-ment of the Standard. Interpretations can only
37、be rendered in response to a written request sentto the Secretary of the B16 Standards Committee.The request for interpretation 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)
38、and the topic of the inquiry.Edition: Cite the applicable edition of the Standard for which the interpretation isbeing requested.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
39、proprietary design or situation. The inquirer may also include any plansor drawings, which are necessary to explain the question; 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 answ
40、ered, which may inadvertently change the intent 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
41、 Committee or Subcommittee. ASME does not“approve,” “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 co
42、ntact the Secretary ofthe B16 Standards Committee.viCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME B16.25-2007BUTTWELDING ENDS1 SCOPE1.1 GeneralThis Standard covers the preparation of buttwe
43、ldingends of piping components to be joined into a pipingsystem by welding. It 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 t
44、he following:(a) no backing rings(b) split or noncontinuous backing rings(c) solid 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 St
45、andard applies to any metallic materials forwhich a welding procedure can be satisfactorilyqualified, 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
46、 UnitsThe values stated in either metric or inch units are tobe regarded separately as the standard. 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
47、 the two systems may result innonconformance with this Standard.1.4 SizeNominal pipe size (NPS), 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 follow
48、s:NPS DN12153420125114321124025021265384 1001For NPS 4, the related DNp25 H11547 NPS.1.5 Referenced StandardsStandards 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 e
49、dition of each standard andspecification in the individual references; instead, thespecific edition is identified 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 SystemsNonman
