1、AWS Resourcesfor EngineersSymbols forJoining andInspectionwelding know-how for engineersii 2001 by American Welding SocietyAll rights reservedNo portion of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by anymeans, including mechanical, photocopying, record
2、ing, or otherwise, without the prior written permission of thecopyright owner.Authorization to photocopy items for internal, personal, or educational classroom use only, or the internal,personal, or educational classroom use only of specific clients, is granted by the American Welding Society (AWS)p
3、rovided the appropriate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA01923; telephone: (978) 750-8400; Internet: .The Welding Handbook is the result of the collective effort of many volunteer technical specialists who provideinformation to assist with the design and
4、application of welding and allied processes.The information and data presented in the Welding Handbook, and this chapter, are intended for informationalpurposes only. Reasonable care is exercised in the compilation and publication of the Welding Handbook to ensurethe authenticity of the contents. Ho
5、wever, no representation is made as to the accuracy, reliability, or completenessof this information, and an independent, substantiating investigation of the information should be undertaken bythe user.The information contained in the Welding Handbook shall not be construed as a grant of any right o
6、f manufac-ture, sale, use, or reproduction in connection with any method, process, apparatus, product, composition, or sys-tem, which is covered by patent, copyright, or trademark. Also, it shall not be construed as a defense against anyliability for such infringement. Whether the use of any informa
7、tion in the Welding Handbook would result in aninfringement of any patent, copyright, or trademark is a determination to be made by the user.Printed in the United States of AmericaiiiACKNOWLEDGMENTSThis chapter from the Welding Handbook, Ninth Edition, Volumn 1, “Welding Science and Technology,” has
8、 beenselected by the AWS Product Development Committee as a service to industry professionals.The Welding Handbook Committee and the editors recognize the contributions of the volunteers who have cre-ated, developed, and documented the technology of welding and shared it in the past editions of the
9、WeldingHandbook. The same enthusiasm, dedication, and willingness to share that they made a tradition continue withthis ninth edition of the Welding Handbook.The Welding Handbook Committee and the editors extend appreciation to the AWS technical committees whodeveloped the current consensus standard
10、s that pertain to this volume. They are also grateful to L. P. Connor,editor of Volume 1, eighth edition, and the members of the AWS technical staff for the engineering assistance theygenerously contributed.ivCONTRIBUTORSWELDING HANDBOOK COMMITTEEH. R. Castner, Chair Edison Welding InstituteB. J. Ba
11、stian, First Vice-Chair Benmar AssociatesR. S. Funderburk The Lincoln Electric CompanyJ. M. Gerken, Sr. ConsultantI. D. Harris Edison Welding InstituteL. C. Heckendorn Intech R however, as codes and stan-dards undergo frequent revision, the reader is encouraged to consultthe most recent edition.4. A
12、merican Welding Society (AWS) Committee on Definitions,2001, Standard Welding Terms and Definitions, AWS A3.0:2001,Miami: American Welding Society.SYMBOLSFOR JOINING AND INSPECTIONCHAPTER 9SYMBOLS FOR JOINING AND INSPECTION 3FUNDAMENTALSAs symbols are used to specify joining and inspectioninformatio
13、n, this section begins with a description ofthe desired product, the welded joint. A joint is a junc-tion of the members or the edges of the members thatare to be joined or have been joined. The five basicjoints used in welding and brazing design are the butt,corner, T-, lap, and edge joints. Schema
14、tic illustrationsof these joints are presented in Figure 1.Once the desired joints have been designed, weldingsymbols are typically used on the engineering drawingto specify the required welding information and details.When the details of the weld cannot be adequately com-municated by means of weldi
15、ng symbols, additionalinformation is specified in a notation on the drawing.Symbols may be drawn by any methodelectronic,mechanical, or freehand. They must be clear and legibleregardless of the method used.While the use of metric units is growing, U.S. cus-tomary units can still be used in welding a
16、nd examina-tion symbols. However, dual units (i.e., both U.S.customary and SI units) must not be used. If desired, atable of conversions may be included on the drawing.Suggested size dimensions for welding symbol elementsare provided in Standard Symbols for Welding, Brazing,and Nondestructive Examin
17、ation, ANSI/AWS A2.4.5With respect to terminology, it is important to note thatthe terms weld symbol and welding symbol have differentmeanings. The weld symbol specifies the type of weld thatis prescribed for the application. The weld symbol is partof the welding symbol. Groove weld symbols are simi
18、larin shape to the cross section of the desired groove. Othersymbols, such as those used for stud and seam welds, aresimilar in shape to the characteristics of these weldsviewed from other orientations. Figure 2 presents the weldsymbols used for various common welds.WELDING SYMBOLSWelding symbols ar
19、e used to communicate require-ments for the desired welding. They typically includethe weld symbol and specify the weld location, type,size, and length.The basic welding symbol is comprised of the refer-ence line, about which the weld symbol and dimensionsare located, and an arrow, designating the l
20、ocation forthe weld. As shown in Figure 3, a tail may be includedin the symbol to provide an area to communicate infor-mation about the welding specification, the weldingprocess, or other reference data.5. See Reference 2.A complete welding symbol consists of the followingelements:1. Reference line
21、(required);2. Arrow (required);3. Tail;4. Basic weld symbol;5. Dimensions and other data;6. Finish symbols;7. Specification, process, or other references; and8. Supplementary symbols.The elements of the welding symbol have a standardlocation with respect to one another. The location of theelements i
22、n the welding symbol is illustrated in Figure 4.Apart from the reference line and arrow, which arerequired, only those elements that provide the requiredclarity need be specified. The required and optional ele-ments of the welding symbol are described in detail below.Reference LineThe reference line
23、 is the basic and required weldingsymbol element about which the weld information islocated. The reference line is oriented horizontally.Multiple Reference Lines. As shown in Figure 5,two or more reference lines may be used with a singlearrow to indicate a sequence of operations. The refer-ence line
24、 nearest the tip of the arrow specifies the firstoperation. The second or more reference lines representthe subsequent operations. Subsequent operations areshown sequentially on other reference lines leadingaway from the tip of the arrow.Reference lines are also used to specify data to sup-plement t
25、he welding symbol and to indicate inspectionrequirements. Figure 6 illustrates the application ofmultiple reference lines to give clear guidance on theprocedures (e.g., gouging to sound metal for the weldfrom the second side).ArrowThe significance of the arrow is illustrated in Figure7. Used in conj
26、unction with the reference line, thearrow establishes the locations of the arrow side andthe other side of a joint, as shown in Figure 7(A). Thearrow clearly points to the location on the drawing thatidentifies the intended joint to which the weldinginstructions apply. The arrow side of the referenc
27、e lineis always closest to the reader when the drawing isviewed from the bottom and the reference line is drawn,as preferred, in a horizontal plane. Likewise, the otherside of the line provides instructions for the side of thejoint furthest from the arrow.4 SYMBOLS FOR JOINING AND INSPECTIONSource:
28、American Welding Society (AWS) Committee on Definitions and Symbols, 1998, Standard Symbols for Welding, Brazing, and NondestructiveExamination, ANSI/AWS A2.4-98, Miami: American Welding Society, Figure 4.Figure 1Basic JointsSYMBOLS FOR JOINING AND INSPECTION 5Figure 7(A) offers examples of the use
29、of the terms“arrow side” and “other side” for three commonjoint geometries. The weld symbol specifying anarrow-side weld is always placed on the lower side ofthe reference line, as shown in Figure 7(B). On theother hand, the weld symbol depicting an other-sideweld is placed on the upper side of the
30、reference line,that is, away from the reader when viewed from thebottom, as shown in Figure 7(C). Welds on both sidesof a joint are prescribed by placing weld symbols onboth sides of the reference line, as depicted in Figure7(D).Note: The reference line is depicted as a dashed line for illustrative
31、purposes.Source: Adapted from American Welding Society (AWS) Committee on Definitions and Symbols, 1998, Standard Symbols for Welding, Brazing, and Nondestructive Examination,ANSI/AWS A2.4-98, Miami: American Welding Society, Figure 1.Figure 2Weld SymbolsFigure 3Standard Welding Symbol6 SYMBOLS FOR
32、JOINING AND INSPECTIONSource: Adapted from American Welding Society (AWS) Committee on Definitions and Symbols, 1998, Standard Symbols for Welding, Brazing, and Nondestructive Examination,ANSI/AWS A2.4-98, Miami: American Welding Society, Figure 2.Figure 4Standard Location of the Elements of the Wel
33、ding SymbolSource: Adapted from American Welding Society (AWS) Committee on Definitions and Symbols, 1998, Standard Symbols for Welding, Brazing, and Nondestructive Examination,ANSI/AWS A2.4-98, Miami: American Welding Society, p. 6.Figure 5Multiple Reference LinesSYMBOLS FOR JOINING AND INSPECTION
34、7Some weld symbols have no arrow-side or other-sidesignificance. However, supplementary symbols (seebelow) used in conjunction with these weld symbols canconvey such significance. For example, weld symbolsfor resistance spot and seam welding have no side sig-nificance, as can be observed in Figure 7
35、(E). However,gas tungsten arc welding (GTAW), electron beam weld-ing (EBW), or other spot and seam welds may havearrow- and other-side significance.TailWhen a specification, process, test, or other referenceis needed to convey additional requirements of the jointto be manufactured, this information
36、is placed in a tailof the symbol, as shown in Figure 7(F). The illustrationson the left and in the center indicate specifications,codes, or other referenced documents. In the illustrationon the right, the letter designation “CJP” is used in thetail of the welding symbol to specify that a completejoi
37、nt penetration groove weld is required, regardless ofthe joint geometry. As previously explained, the tailmay be omitted when no specification, process, or otherreference is included in the welding symbol.Supplementary Data. The tails of any additionalreference lines used in the welding symbol conve
38、y datathat is supplementary to the basic information pre-sented in the welding symbol. Examples of supplemen-tary information include the process, process variation,method of application, and welding procedure number.Figure 8 illustrates the communication of supplemen-tary data in additional referen
39、ce lines.Basic Weld SymbolSixteen basic weld symbols are used. These are shownin Figure 2.Dimensions and Other DataThe dimensions of a weld are shown on the sameside of the reference line as the basic weld symbol. Thesize of the weld is shown to the left of the weld symbol,and the length of the weld
40、 is shown on the right. If alength is not given, the weld symbol applies to that por-tion of the joint between abrupt changes in the direc-tion of welding or between specified dimension lines. Ifa weld symbol is shown on each side of the referenceFigure 6Application of Multiple Reference Lines8 SYMB
41、OLS FOR JOINING AND INSPECTIONline, the dimensions, if used, must be given for eachweld even though both welds are identical.Either the U.S. customary system of measurement orthe International System of Units (SI) may be used whenspecifying dimensions. However, as noted above, onlyone system should
42、be used for a project or product.Examples of symbols indicating the dimensions oftypical fillet welds are shown in Figure 9. In Figure9(A), a 5/16 in. fillet weld is specified for the arrow sideof the T-joint. In Figure 9(B), 1/2 in. fillet welds arespecified for the arrow side and the other side of
43、 the T-joint. In Figure 9(C), a 3/8 in. fillet weld and a 1/4 in.fillet weld are specified for the arrow side and the otherside of a T-joint, respectively. In Figure 9(D), a filletweld having one 1/4 in. leg and one 1/2 in. leg is speci-fied for the arrow side of the T-joint. The dimensions“1/4 1/2”
44、 noted adjacent to the fillet weld symbol donot specify leg orientation, so the drawing and a refer-ence in the tail are used to clarify the requirements. InFigure 9(E), a continuous fillet weld is required on theFigure 7Significance of the Arrow in the Welding SymbolSYMBOLS FOR JOINING AND INSPECTI
45、ON 9arrow side of the joint since no weld length is specifiednumerically to the right of the fillet weld symbol. Thesize of the fillet weld is not specified. In Figure 9(F), afillet weld 12 in. in length is specified on the arrow sideof the joint. The specific location of the 12 in. long weldis show
46、n by the notation “3 in.” on the drawing. Thesize of the fillet weld is not specified.If a weld in a joint is to be intermittent, the length ofthe segments and the pitch (i.e., the center-to-centerspacing) are placed to the right of the weld symbol, ascan be observed in Figure 10.Finishing SymbolsFi
47、nishing symbols can be used to specify a mechani-cal method of achieving the required weld control. Theyare used in conjunction with contour symbols (see“Supplementary Symbols”). Figure 11 presents the fin-ishing symbols and their meaning.Specification, Process, and Other ReferencesWelding symbols a
48、lso offer a means of conveyingother more detailed welding requirements or instruc-tions. Most often, this information is included in thetail of the welding symbol.Any applicable job specification number or code ref-erence may be incorporated into the tail of a weldingsymbol. In addition, consumable
49、insert class and back-ing or spacer material specification and dimensions maybe shown. The publication Standard Symbols for Weld-ing, Brazing, and Nondestructive Examination, ANSI/AWS 2.4,6should be consulted for additional applica-tions of specifications to welding symbols.Letter designations are used in the tail of a weldingsymbol to communicate the intended welding or braz-ing process. The more frequently used welding processdesignations are listed in Table 1. A complete listing ofdesignations for welding, brazing, and allied processesis given in Standard Symbols
