2002_2007.pdf

ASME B18.2.7.1M-2002METRIC 12-SPLINEFLANGE SCREWSA N A M E R I C A N N A T I O N A LS T A N D A R DASME B18.2.7.1M-2002METRIC12-SPLINEFLANGE SCREWSA N A M E R I C A N N A T I O N A LS T A N D A R DREAFFIRMED 2007FOR CURRENT COMMITTEE PERSONNELPLEASE E-MAIL CSasme.orgAN AMERICAN NA TIONALST ANDARDMETRIC12-SPLINEFLANGE SCREWSASME B18.2.7.1M-2002Date of Issuance:March 15,2002This Standard will be revised when the Society approves the issuance of anew edition.There will be no addenda issued to this edition.ASME will issue written replies to inquiries concerning interpretation oftechnical aspects of this Standard.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 forAmerican National Standards.The Standards Committee that approved the code or standardwas balanced to assure that individuals from competent and concerned interests have had anopportunity to participate.The proposed code or standard was made available for public reviewand 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 patent rights asserted inconnection withany itemsmentioned inthis document,and doesnot undertaketo insureanyoneutilizing a standard against liability for infringement of any applicable letters patent,nor assumeany such liability.Users of a code or standard are expressly advised that determination of thevalidity of any such patent rights,and the risk of infringement of such rights,is entirely theirown responsibility.Participation by federal agency representative(s)or person(s)affiliated with industry is not tobe interpreted as government or industry endorsement of this code or standard.ASME accepts responsibility for only those interpretations of this document issued inaccordance with the established ASME procedures and policies,which precludes the issuanceof 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 2002 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll Rights ReservedPrinted in U.S.A.CONTENTSForeword.vCommittee Roster.viCorrespondence With the B18 Committee.viii1General Data.11.11Scope.2Comparison With ISO Standards.13Referenced Standards.14Dimensions.25Spline.26Top of Head.27Head Height.38Spline Height.39Position of Head.310Flange.311Bearing Surface.312Fillet.313Body Diameter.314Length.415Point.416Straightness.417Thread Length.617.16Grip Gaging Length,Lgmax.17.28Body Length,Lsmin.17.38Nominal Thread Length,B.17.48Transition Thread Length,X.18Threads.818.18Thread Series and Tolerance Class.iii18.28Acceptability.19Material and Mechanical Properties.819.18Steel.19.28Corrosion-Resistant Steels.19.38Nonferrous Metals.20Finish.821Identification Symbols.821.19Property Class Symbols.21.29Source Symbols.22Options.923Terminology.924Workmanship.925Clearance Holes.926Designation.927Inspection and Quality Assurance.928Dimensional Conformance.9Tables1Wrenching Configurations for 12-Spline Flange Screws.22Position Tolerance,Circular Runout,and Minimum Body Diameter.33Fillet Configuration Dimensions.44Dimensions of 12-Spline Flange Screws.55Dimensions of Reduced Body Diameter(Type R).66Screw Length Tolerances.67Point Radius.68Maximum Grip Gaging Lengths,Lg,and Minimum Body Lengths,Ls,for 12-SplineFlange Screws.7Nonmandatory AppendixAScrew Straightness and Gaging Procedure.11ivFOREWORDAmerican National Standards Committee B18 for the standardization of bolts,screws,nuts,rivets,and similar fasteners was organized in March 1922 as Sectional CommitteeB18 under the aegis of the American Engineering Standards Committee(later the AmericanStandards Association,then the United States of America Standards Institute and,as ofOctober 6,1969,the American National Standards Institute,Inc.),with the Society ofAutomotive Engineers and the American Society of Mechancial Engineers as joint sponsors.Subcommittee 2 was subsequently established and charged with the responsibility for technicalcontent of standards covering wrench head bolts and nuts.In 1971,the ANSI Special Study Committee began an investigation of optimum headdesigns for metric fasteners.A new head configuration which would have superior performancecapabilities when compared to a standard hexagon head design was envisioned.These studiesled to the development of a 12-spline flanged screw which was determined to have thefollowing advantages:(a)Lower nominal bearing pressures(b)Flange protection of assembled surfaces against abrasion due to wrenching tools(c)Lower stress concentration factors in head-to-shank fille