1、Designation:D274922An American National StandardStandard Symbols forDimensions of Plastic Pipe Fittings1This standard is issued under the fixed designation D2749;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revisi
2、on.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 These symbols specify terminology for the dimensionsof pipe fittings made of plastic materials.It consists of a list ofletter designat
3、ions with definitions,followed by drawings oftypical fittings,with the significant dimensions labeled inaccordance with these letter designations.1.2 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on
4、 Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2F1498 Specification for Taper Pipe Threads 60 for Thermo-plastic Pipe and Fittings3.Letter D
5、esignations of Dimensions3.1 The letter designations are defined as follows:A=socket entrance diameter,measured at intersectionof socket diameter and chamfer or radius,regardless of length“C”,B=socket bottom diameter,measured at intersectionof socket diameter and radius,C=socket depth,measured from
6、socket entrance faceto socket bottom face,D=inside diameter of body,E=wall thickness of socket,min,F=wall thickness of body,G=intersection of socket center lines to socket bottom(center-to-socket bottom),90 elbows,tees,crosses,and shoulderon insert fittings;a laying length,H=intersection of socket c
7、enter lines to end of fitting(center-to-end),90 elbows,tees,crosses;center to face,J=intersection of socket center lines to socket bottom(center-to-socket bottom),45 elbow;a laying length,K=intersection of socket center lines to end of fitting(center-to-end),45 elbow,L=length over-all,coupling,M=out
8、side diameter of hub,N=socket bottom to socket bottom or seat thickness(center stop thickness or pipe stop thickness),P=insert length,Q=distance or width across flat,R=height of head,S=length of male thread,includes pilot,T=length of female thread,includes pilot,V=root diameter of barbs,W=cap height
9、,XA=male end of spigot at top,see Fig.1,XB=male end of spigot at bottom,see Fig.1Y=length of barb section,Z=outside diameter of barbsCB=Pilot on the first thread of internal andexternal threaded fittings equal to12to34the width of the thread pitchas described in Specification F1498,Section 4.5 andFi
10、gures 2b and 2c.CM=length of male end,bushing,DJ=inside diameter,major,bushing,EJ=wall thickness of socket,major,bushing;wall thickness of male end,bushing,EN=wall thickness of socket,minor,bushing,EW=radius on socket entrance,EX=thickness with 30 taper on socket entrance;30 entrance chamfer width,a
11、ndEZ=thickness with 45 taper on socket entrance;45 entrance chamfer width.3.2 When there are two different values for one categoricaldimension on a fitting,the large one shall be designated withthe letter for that category followed by a J meaning major,andthe small one shall be designated by the sam
12、e letter followedby an N meaning minor;for example,on a 45-deg Y-branch,there are two J dimensions,the longer one is designated as JJand the shorter one as JN.When there are more than twodifferent values for one categorical dimension,they are desig-nated with the proper letter followed by an arabic
13、number;for1These symbols are under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.10 on Fittings.Current edition approved July 1,2022.Published July 2022.Originally approvedin 1968.Last previous edition approved 2013 as D2749 13 w
14、hich was withdrawnMarch 2022 and reinstated in July 2022.DOI:10.1520/D2749-22.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe A
15、STM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment o
16、f International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1example,L1,L2,and L3 for the three lengths on a plasticadapter to connect plastic pipe to a cast iron hub.4.Illustrations4.1 Illustrations of typical fittings are shown in Figs.2-22.5.Keywords5.1 plastic pipe fitting;symbol definitions;symbols fordimensionsFIG.1 Reducer Bushings-SocketFIG.2 Tapered SocketD2749 222FIG.3 90 Elbow-SocketFIG.4 45 Elbow-SocketFIG.5 Te
