1、AN AMERICAN NATIO NAL STANDARDScrew Threads:Nomenclature,Definitions,and Letter Symbols ASME B1.7-2006(Revision of ANSI/ASME B1.7M-1984)Copyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distri
2、bution is permitted.Uncontrolled when printed.ASME B1.7-2006(Revision of ANSI/ASME B1.7M-1984)Screw Threads:Nomenclature,Definitions,andLetter SymbolsThree Park Avenue New York,NY 10016AN AMERICAN NATIONAL STANDARDCopyrighted material licensed to Stanford University by Thomson Scientific(),downloade
3、d on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.Date of Issuance:November 17,2006This Standard will be revised when the Society approves the issuance of a new edition.There will beno addenda or written interpretations of the
4、 requirements of this Standard issued to this edition.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under the procedures accredited as meeting the criteria for American NationalStandards.The Standards Committee that approved the
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10、cal EngineersThree Park Avenue,New York,NY 10016-5990Copyright 2006 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.Copyrighted material licensed to Stanford University by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduc
11、tion or distribution is permitted.Uncontrolled when printed.CONTENTSForeword.vCommittee Roster .vi1General .12Definition of Terms .1Figures1Allowance.22Axis of Thread .23Best Wire Size.24Blunt Start Thread .35Bottom of Chamfer.46Clearance Flank .47Countersink .48Crest.49Root and Crest Truncation.510
12、Fundamental Deviation .611Metric Tolerance System for Screw Threads .712Element.713Flank.714Flank Angle .715Flat Form .716Following Flank .817Gauge Plane .818Height of Fundamental Triangle .819Height of Thread .920Height of Thread Engagement.921Helix.922Helix Variation(Drunken Thread).923Incomplete
13、Thread .1024Interference Fit .1125Internal Thread.1126Lead .1127Leading Flank.1128Gaging Length .1129Length of Assembly .1130Length of Thread Engagement.1231Load Flank .1232Major Clearance .1233Major Diameter,External Thread.1234Major Diameter,Internal Thread .1235Major Diameter,Internal Thread(Roun
14、ded Form).1236Major Diameter,Taper Thread.1237Minor Clearance.1338Minor Diameter,External Thread(Flat Form).1439Minor Diameter,External Thread(Rounded Form).1440Minor Diameter,Internal Thread.1441Minor Diameter,Taper Thread .1442Multiple Start Thread.14iiiCopyrighted material licensed to Stanford Un
15、iversity by Thomson Scientific(),downloaded on Oct-05-2010 by Stanford University User.No further reproduction or distribution is permitted.Uncontrolled when printed.43Pitch .1444Pitch Cone .1445Pitch Cylinder .1446Pitch Diameter,External Thread .1547Pitch Diameter,Internal Thread.1548Plane of Vanis
16、h Point.1549Profile,Basic Thread.1650Root Radius .1651Screw Thread .1652Sharp Crest and Root.1653Shear Area .1754Straight Thread.1855Thread Angle .2356Thread Ridge Thickness.2357Truncation .2358Vanish Cone.24Tables1General Symbols.192ISO General Symbols .203Thread Series Designations .214ISO Thread Series Designations .22Nonmandatory AppendicesASuperseded Thread Series Designations.25BISO Symbols for Screw Threads.26CGreek Alphabet .27ivCopyrighted material licensed to Stanford University by Tho
