2012_2021.pdf

AN AMERICAN NATIONAL STANDARD ASME B18.2.6M-2012Revision,redesignation,and consolidation ofASME B18.2.3.7M-1979(R2006)and ASME B18.2.4.6M-2010Metric Fasteners for Use in Structural ApplicationsREAFFIRMED 2021ASME B18.2.6M-2012Revision,redesignation,and consolidation ofASME B18.2.3.7M-1979(R2006)and ASME B18.2.4.6M-2010Metric Fastenersfor Use inStructuralApplicationsAN AMERICAN NATIONAL STANDARDThree Park Avenue New York,NY 10016 USADate of Issuance:March 23,2012This Standard will be revised when the Society approves the issuance of a new 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.Errata to codes and standards may be posted on the ASME Web site under the Committee Pages toprovide corrections to incorrectly published items,or to correct typographical or grammatical errorsin codes and standards.Such errata shall be used on the date posted.The Committee Pages can be found at http:/cstools.asme.org/.There is an option available toautomatically receive an e-mail notification when errata are posted to a particular code or standard.ThisoptioncanbefoundontheappropriateCommitteePageafterselecting“Errata”inthe“PublicationInformation”section.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 2012 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword.ivCommittee Roster.vCorrespondence With the B18 Committee.vi1Introduction.12Metric Heavy Hex Structural Bolts:ASTM A325M and ASTM A490M.23Metric Heavy Hex Nuts:ASTM A563M.54Metric Hardened Steel Washers:ASTM F436M.65Metric Compressible Washer-Type Direct Tension Indicators:ASTM F959M.7Tables1Dimensions of Metric Heavy Hex Structural Bolts.22Maximum Grip Gaging Lengths and Minimum Body Lengths for Metric HeavyHex Structural Bolts.43Dimensions of Metric Heavy Hex Nuts for Use With Structural Bolts.64Dimensions of Metric Hardened Steel Circular and Circular Clipped Washers.75Dimensions for Metric Compressible Washer-Type Direct Tension Indicators.8iiiFOREWORDIn the spring of 2010,the B18 Committee decided that a metric version of ASME B18.2.6,Fasteners for Use in Structural Applications,should be created for fastener guidance on metricstructural fasteners used in North America.This Standard,ASME B18.2.6M,is the result of thateffort.It was decided that since there were not yet any ASTM material and testing standards fortwist-off bolts,their dimensions should not be included in this initial edition of this Standard.This Standard does include the dimensions for metric structural bolts,metric heavy hex nuts,metric structural washers,and metric compressible-washer-type direct tension indicators.Suggestions for improvement of this Standard are welcome.They should be addressed to theSecretary,ASME B18 Standards Committee,Three Park Avenue,New York,NY 10016-5990.This Standard was approved as an American National Standard on February 9,2012.ivASME B18 COMMITTEEStandardization of Bolts,Nuts,Rivets,Screws,Washers,andSimilar Fasteners(The following is the ros