2-5M_Edtn_2009.pdf

AN AMERICAN NATIO NAL STANDARD ASME B18.2.5M-2009Metric 12-Point Flange ScrewsCopyright 2009 by the American Society of Mechanical Engineers.No reproduction may be made of this material without written consent of ASME.cCopyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.ASME B18.2.5M-2009Metric 12-PointFlange ScrewsAN AMERICAN NATIONAL STANDARDCopyright 2009 by the American Society of Mechanical Engineers.No reproduction may be made of this material without written consent of ASME.cCopyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.Date of Issuance:August 14,2009This Standard will be revised when the Society approves the issuance of a new edition.There willbe no addenda issued to this edition.ASME issues written replies to inquiries concerning interpretations of technical aspects of thisStandard.Periodically certain actions of the ASME B18 Committee may be published as Cases.Cases and 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 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 forpublic review andcomment thatprovides an opportunityfor additional publicinput 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 patent 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 determination 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 standard.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 system or otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue,New York,NY 10016-5990Copyright 2009 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.Copyright 2009 by the American Society of Mechanical Engineers.No reproduction may be made of this material without written consent of ASME.cCopyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.CONTENTSForeword.vCommittee Roster.viCorrespondence With the B18 Committee.vii1Scope.12Comparison With ISO Standards.13Referenced Standards.14Terminology.15Dimensions.16Top of Head.17Head Height.18Wrenching Height.29Gaging of 12-Point Flange Head.210Position of Head.211Flange.212Bearing Surface.213Fillet.214Body Diameter.215Length.216Points.217Straightness.218Threads.519Thread Length.520Materials and Mechanical Properties.921Identification Symbols.922Finish.923Workmanship.924Inspection and Quality Assurance.925Dimensional Conformance.1026Clearance Holes.1027Designation.10Tables1Dimensions of 12-Point Flange Screws.32Gaging of 12-Point Flange Head.43Tolerance Zones.44Dimensions of Type F Underhead Fillets.5iiiCopyright 2009 by the American Society of Mechanical Engineers.No reproduction may be made of this material without written consent of ASME.cCopyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.5Dimensions of Type U Underhead Fillets.66Dimensions of Reduced Body Diameter(Type R).77Length Tolerances,L,mm.78Dimensions of Points.79Maximum Grip Lengths,LG,and Minimum Body Lengths,Ls.810Thread Lengths.9ivCopyright 2009 by the American Society of Mechanical Engineers.No reproduction may be made of this material without written consent of ASME.cCopyrighted m