1、AN AMERICAN NATIONAL STANDARDASME Y14.2-2008Revision of ASME Y14.2M-1992 (R2003)Line Conventions and LetteringEngineering Drawing and Related Documentation PracticesCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without lice
2、nse from IHS-,-,-ASME Y14.2ADOPTION NOTICEASME Y14.2, Line Conventions and Lettering, was adopted on 30 September, 2008 for use by the Department ofDefense(DoD).ProposedchangesbyDoDactivitiesmustbesubmittedtotheDoDAdoptingActivity:Commander,U.S. Army Research, Development and Engineering Center (ARD
3、EC), ATTN: AMSRD-AAR-QES-E, PicatinnyArsenal, NJ 07806-5000. Copies of this document may be purchased from The American Society of MechanicalEngineers (ASME), Three Park Avenue, New York, NY 10016-5990. http:/www.asme.orgCustodians: Adopting Activity:Army AR Army ARNavy SAAir Force 16 (ProjectDRPR-2
4、008-006)Review Activities:Army CR, IE, MI, PT, TM2Navy AS, CG, CH, EC, MC, NP, TDAir Force 13, 99DLADHOSDSENSANSOther CM, MP, DC2NOTE: Theactivitieslistedabovewereinterestedinthisdocumentasofthedateofthisdocument.Sinceorganizationsandresponsibili-ties can change, you should verify the currency of th
5、e information above using the ASSIST Online database at http:/assist.daps.dla.mil.AMSC N/A AREA DRPRDISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited.Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permit
6、ted without license from IHS-,-,-ASME Y14.2-2008Revision of ASME Y14.2M-1992 (R2003)Line Conventionsand LetteringEngineering Drawing and RelatedDocumentation PracticesAN AMERICAN NATIONAL STANDARDCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or ne
7、tworking permitted without license from IHS-,-,-Date of Issuance: December 3, 2008This Standard will be revised when the Society approves the issuance of a new edition. There willbe no addenda or written interpretations of the requirements of this Standard issued to this edition.Periodically certain
8、 actions of the ASME Y14 Committee may be published as Cases. Cases arepublished on the ASME Web site under the Committee Pages at http:/cstools.asme.org as they areissued.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under proce
9、dures 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 fo
10、r 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 “approve,” “rate,” or “endorse” any item, construction, proprietary device, or activity.ASME does not take any position with respect
11、 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 expr
12、esslyadvised 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 endors
13、ement 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 a
14、n 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 2008 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.Copyright ASME Inter
15、national Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-CONTENTSForeword ivCommittee Roster . vCorrespondence With the Y14 Committee vi1 General. 12 Line Conventions 13 Arrowheads. 84 Lettering . 8Figures1 Width and Types of
16、 Lines 22 Applications of Lines 33 Hidden Line Techniques and Symmetry Line Application . 44 Section Lining of Adjacent Parts . 45 Direction of Section Lines 56 Full Section 57 Outline Section Lining . 68 Arrowhead Placement on Dimension Lines . 79 Special Applications of Extension Lines 710 Termina
17、tion of Leaders 711 Phantom Line Applications 912 Arrowhead Styles 1013 Inclined Letters 1014 Vertical Letters 11Table1 Minimum Letter Heights (Millimeter) 11Mandatory AppendixI Minimum Letter Heights (Inch) 13iiiCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo r
18、eproduction or networking permitted without license from IHS-,-,-FOREWORDThis revision was prepared by Subcommittee 2 of the ASME Y14 Committee, EngineeringDrawing and Related Documentation Practices. The successful completion of this revision isattributed to the Subcommittee members, the support of
19、 their respective companies/organiza-tions, and the U. S. Department of Defense departments and agencies that participated in thereview process.It consists primarily of minor changes to the text to enhance readability. The more substantialchanges are as follows:(a) A “no terminator“ option for datum
20、 targets was added to the terminator options.(b) The rules for crossing leader lines were rewritten for consistency.(c) Due to changes in drawing preparation since the last revision, the lettering type sectionhas been greatly simplified.(d) All the figures have been redrawn.Suggestions for improveme
21、nt of this Standard are welcome. They should be sent to TheAmerican Society of Mechanical Engineers; Attn: Secretary, Y14 Standards Committee; ThreePark Ave., New York, NY 10016-5990.This revision was approved as an American National Standard on September 19, 2008.ivCopyright ASME International Prov
22、ided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME Y14 COMMITTEEEngineering Drawing and Related Documentation Practices(The following is the roster of the Committee at the time of approval of this Standard.)STANDARDS COMMITTEE
23、OFFICERSF. Bakos, Jr., ChairK. E. Wiegandt, Vice ChairC. J. Gomez, SecretarySTANDARDS COMMITTEE PERSONNELA. R. Anderson, Dimensional Control Systems, Inc.J. B. Baker, ConsultantF. Bakos, Jr., ConsultantJ. V. Burleigh, ConsultantR. A. Chadderdon, Southwest ConsultantsD. E. Day, TEC-EASE, Inc.K. Dober
24、t, UGS PLM SolutionsC. W. Ferguson, WM Education ServicesL. W. Foster, L. W. Foster Order Dept: 22 Law Drive, P. O. Box2900, Fairfield, NJ 07007-29002 LINE CONVENTIONSLine conventions describe the size, construction, andapplication of the various lines used in making draw-ings. Paragraphs 2.1 throug
25、h 2.14 identify the type andstyle of lines for use on drawings.2.1 Line WidthsTwo widths of lines should be used on drawings (seeFig. 1). The thin line width shall be 0.3 mm minimum.The thick line width shall be 0.6 mm minimum. Theseapproximate line widths are intended to differentiatebetween thick
26、and thin lines and are not values for con-trol of acceptance or rejection of drawings. All lines ofthe same type shall be uniform throughout the drawing.The ratio of line widths should be approximately two-to-one (2:1).12.2 Line SpacingSpacing between parallel lines may be exaggerated toa maximum of
27、 3 mm, so there is no fill-in when thedrawing is reproduced.2.3 Visible LinesVisible lines are continuous and shall be used for rep-resenting visible edges or contours of objects (see Figs. 1and 2).2.4 Projection LineProjection lines are lines used to indicate the line ofsight between two successive
28、 orthographic views.2.5 Hidden LinesHidden lines are used to represent hidden edges andcontours. They consist of short evenly spaced dashesand are used to show the hidden features of an object(see Figs. 1 and 2). The length of the dashes may varyslightly in relation to the scale of the view.Hidden l
29、ines should begin and end with a dash incontact with the visible or hidden line from which theystart or end, except when such a dash would form acontinuation of a visible line or when a CAD system haslimitations that cannot comply with these requirements.Dashesshouldjoinatcorners,andarcsshouldstartw
30、ithdashes at tangent points (see Fig. 3).When features located behind transparent materialsare depicted, they shall be treated as concealed featuresand shown with hidden lines. Hidden lines should beomitted when their use is not required for the clarity ofthe drawing.2.6 Section LinesSectionlinesare
31、usedtoshowsurfacescutbyacuttingplane. They are drawn as a pattern of straight, equallyspaced, parallel lines used to indicate the cut surfacesof an object in section views (see Figs. 1 and 2).2.6.1 General Principles. Cut surfaces of sectionalviews may be identified by using section lines. Sectionli
32、nes are optional and may be used when necessary todistinguish individual components of an assembly or todistinguish different surface levels of a full or partialsection through a part (see ASME Y14.3M).Lettering should not be placed in section areas. How-ever when it is unavoidable, the section line
33、s shall beomitted in the area for the lettering (see Fig. 4). WhenCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME Y14.2-2008Fig. 1 Width and Types of Lines2Copyright ASME International Provid
34、ed by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME Y14.2-2008Fig. 2 Applications of Lines3Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license
35、from IHS-,-,-ASME Y14.2-2008Fig. 3 Hidden Line Techniques and Symmetry Line ApplicationFig. 4 Section Lining of Adjacent Parts4Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME Y14.2-2008Fig. 5
36、 Direction of Section LinesFig. 6 Full Sectionseveral adjacent parts are shown in a section view, theparts may be sectioned as shown in Fig. 4. For sectionviews of thin materials, see ASME Y14.3M.2.6.2 Direction and Spacing. Section lines shouldbe drawn at a 45 deg angle within the view see Fig. 4,i
37、tem (a). On adjacent parts, the section lines should bedrawn in the opposite direction see Fig. 4, item (b).For additional adjacent parts, any suitable angle maybe used to make each part stand out separately andclearly see Fig. 4, item (c). A suitable angle should bechosen to avoid section lines tha
38、t are parallel or perpen-dicular to visible lines (see Fig. 5). Section lines shallnot meet at common boundaries.Section lines shall be uniformly spaced a minimumof 1.5 mm, and spaced as generously as possible andyetpreservetheunityandcontrastofthesectionedareas(see Fig. 6).Outlinesectionlinesaredra
39、wnadjacenttothebound-aries only of the sectioned area, and are preferred forlarge areas when section lines are required, providedclarity is not sacrificed (see Fig. 7).52.7 Center LinesCenter lines are used to represent axis, center points,or center planes of symmetrical parts and features, boltcirc
40、les, and paths of motion (see Figs. 2 and 3).Center lines shall start and end with long lines andshall intersect by crossing the long lines or short dashes(see Fig. 1). The long line portion of the center line mayvaryinlengthdependingonthescaleoftheview.Centerlines shall extend uniformly and distinc
41、tly a short dis-tancebeyondtheobjectorfeature.Thecenterlinemaybeextended for dimensioning or for some other purpose.Center lines shall not extend through the spacebetween views. Short center lines may be unbrokenwhen no confusion results with other lines.2.8 Symmetry LineSymmetrylinesareusedtoidenti
42、fyaplaneofsymme-try. The plane of symmetry is identified by placing twoshort parallel lines (symmetry lines), drawn at rightangles, crossing a center line near each end and outsidethe boundary of the part (see Fig. 1).Copyright ASME International Provided by IHS under license with ASME Not for Resal
43、eNo reproduction or networking permitted without license from IHS-,-,-ASME Y14.2-2008Fig. 7 Outline Section LiningSymmetry lines are used when representing partiallydrawn views and partial sections of symmetrical parts(see Fig. 3). Visible and hidden lines in symmetricalviews may extend past the cen
44、ter line when clarity isimproved.2.9 Dimension, Extension, and Leader LinesThese are solid lines used to dimension drawings asdescribed in paras. 2.9.1 through 2.9.3.2 (seeASME Y14.5M).2.9.1 Dimension Line. Dimension lines are used toindicate the extent and direction of dimensions, and areterminated
45、 with uniform arrowheads (see Figs. 1 and2). Arrowheads shall be drawn within the limits of thedimension line when possible see Fig. 8, illustration(a). When inadequate space is available, the dimensionlines and arrowheads may be shown outside the dimen-sional limit see Fig. 8, illustration (b).2.9.
46、2 Extension Lines. Extension lines are used toindicate the point or line on the drawing to which thedimension applies (see Figs. 1 and 2). They are also usedto indicate the extension of a surface to a theoreticalintersection (see Fig. 9).2.9.3 Leader Lines. Leader lines are used to directnotes,dimen
47、sions,symbols,itemnumbers,orpartnum-bers on the drawing (see Figs. 1 and 2). A leader lineshould be a straight inclined line, except for a shorthorizontal portion extending to the center of the heightof the first or last letter or digit of the note. Leader linesmay consist of one or more line segmen
48、ts (see Fig. 10).Leaders may be drawn with a hidden line style whenpointing to a hidden surface. The horizontal portion ofthe leader shall not underline the note, and may beomitted entirely.A vertical line may be used at the end of the leaderto group information. When the vertical line is used,6the leader line may terminate at any point on the verti-cal line.2.9.3.1 Terminate leaders as follows:(a) without an arrowhead or dot, when they end ona dimension line see Fig. 10, illustration (a)(b) with a dot 1.5 mm minimum diameter, when the
