1、Designation: B738 13 (Reapproved 2018)Standard Specification forFine-Wire Bunch-Stranded and Rope-Lay Bunch-StrandedCopper Conductors for Use as Electrical Conductors1This standard is issued under the fixed designation B738; the number immediately following the designation indicates the year oforigi
2、nal adoption or, in the case of revision, the year of last revision. 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 This specification covers bare bunch-stranded and rope-lay bunch
3、-stranded conductors made from round copper wiresfiner than No. 40 AWG with diameters less than 0.0031 in.(.078 mm), either coated or uncoated with tin or silver, for useas electrical conductors. (Explanatory Note 1).1.2 The values stated in inch-pound units are to be regardedas standard. The values
4、 given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.2.1 ExceptionsThe SI values for density and tempera-ture are to be regarded as standard.1.3 This international standard was developed in accor-dance with internationa
5、lly recognized principles on standard-ization established in the Decision on 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:2B33 Specific
6、ation for Tin-Coated Soft or Annealed CopperWire for Electrical PurposesB49 Specification for Copper Rod for Electrical PurposesB172 Specification for Rope-Lay-Stranded Copper Conduc-tors Having Bunch-Stranded Members, for Electrical Con-ductorsB174 Specification for Bunch-Stranded Copper Conductors
7、for Electrical ConductorsB193 Test Method for Resistivity of Electrical ConductorMaterialsB258 Specification for Standard Nominal Diameters andCross-Sectional Areas of AWG Sizes of Solid RoundWires Used as Electrical ConductorsB298 Specification for Silver-Coated Soft or Annealed Cop-per WireB354 Te
8、rminology Relating to Uninsulated Metallic Electri-cal Conductors3. Classification3.1 For the purposes of this specification, the followingclassifications have been assigned (Explanatory Note 2):3.1.1 Type:3.1.1.1 Type BBunch-stranded conductors.3.1.1.2 Type RRope-lay bunch-stranded conductors.3.1.2
9、 Class:3.1.2.1 Class RStranded conductors using wire 42 AWG(0.0025).3.1.2.2 Class SStranded conductors using wire 44 AWG(0.0020).3.1.2.3 Class TStranded conductors using wire 46 AWG(0.00157).3.1.2.4 Class UStranded conductors using wire 48 AWG(0.00124).3.1.2.5 Class VStranded conductors using wire 5
10、0 AWG(0.00099).3.2 Detailed information on Type B Conductors is found inTable 1 and Table 2. Detailed information on Type R Conduc-tors is found in Table 3 and Table 2.4. Ordering Information4.1 Orders for materials under this specification shall in-clude the following information:4.1.1 Quantity of
11、each size, class, and type,4.1.2 Conductor sizecircular-mil area, dc resistance (7.1)or AWG (5.2.1),4.1.3 Class and type (Section 3),4.1.4 Whether coated or uncoated; if coated, designate typeof coating (6.1); if silver coated, the minimum thickness ofsilver (6.1.2), and whether tarnish protection i
12、s desired (11.3),4.1.5 Maximum length of lay (5.2.4), if required,4.1.6 Temper (6.2),4.1.7 Separators, if required (5.2.2),4.1.8 Package size (11.1),1This specification is under the jurisdiction of ASTM Committee B01 onElectrical Conductors and is the direct responsibility of Subcommittee B01.04 onC
13、onductors of Copper and Copper Alloys.Current edition approved Oct. 1, 2018. Published October 2018. Originallyapproved in 1984. Last previous edition approved in 2013 as B738 13. DOI:10.1520/B0738-13R18.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Se
14、rvice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in
15、 accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.14.1.9 Special package mark
16、ing, if required (Section 10), and4.1.10 Place of inspection (Section 9).4.2 In addition, Supplementary Requirements shall applyonly when specified by the purchaser in the inquiry, contract, orpurchase order for direct procurement by agencies of the U.S.Government.5. Materials and Manufacture5.1 The
17、 material shall be copper of such quality and puritythat the finished product shall have the properties and charac-teristics described in this specification. Material meeting therequirements of Specification B49 is such a material.5.2 Construction:5.2.1 Cross-Sectional AreaThe cross-sectional area,n
18、umber, and diameter of wires for a variety of strand construc-tions in general use are shown in Table 2.5.2.2 SeparatorsIf a separator is required to be furnishedwith the conductor, it shall be specified by the purchaser at thetime of the order as to the requirements for the kind andthickness of mat
19、erial and its application details.5.2.3 Joints:5.2.3.1 Necessary joints in wires shall be made in accor-dance with accepted commercial practice.5.2.3.2 Joints shall be so constructed and so disposedthroughout the conductor that the diameter or configuration ofthe completed conductor is not substanti
20、ally affected, and thatthe flexibility of the completed conductor is not adverselyaffected.5.2.4 Lay:5.2.4.1 Conductors of the same size and description fur-nished on one order shall have the same lay.5.2.4.2 The direction of the lay of bunch-stranded conduc-tors shall be at the option of the manufa
21、cturer unless otherwisespecified by the purchaser.5.2.4.3 Unless otherwise specified by the purchaser, thelength of the lay of bare or coated bunch-stranded conductorsshall conform to the requirements of Table 4.5.2.4.4 The direction of the lay of the outer layer of rope-laystranded conductors shall
22、 be lefthand, unless otherwise speci-fied by the purchaser.5.2.4.5 The length of the lay of the outer layer of rope-laystranded conductors shall be not less than 8 or more than 16times the outside diameter of the completed conductor. Thelength of the lay of the wires composing the bunch-strandedmemb
23、ers shall be not more than 30 times the diameter of themember.6. Physical Properties6.1 Wire CoatingWhen coated, the coating of the wires ofthe stranded conductor, before stranding, shall conform to therequirements of 6.1.1 or 6.1.2.6.1.1 Tin coating shall conform to the coating requirementsof Speci
24、fication B33.6.1.2 Silver coating shall conform to the minimum thick-ness requirements of the purchase document. Minimum thick-ness shall be determined using the method for determiningplating thickness described in Specification B298.6.1.3 The finished diameter and mass of the coated wiresused shall
25、 be substantially equal to those of the uncoated wiresof the same class.6.2 TemperUnless otherwise specified, all coated conduc-tors shall be furnished in the annealed temper. Uncoatedconductors may be furnished either annealed or unannealed asordered (see 4.1.6).NOTE 1The term unannealed as used in
26、 this specification meanscold-worked conductor as produced on commercial wire-drawing ma-chines.6.3 Tensile Strength and ElongationThe strandedconductor, in its finished form, shall conform to the following:Tensile Strength, min. Elongation, min,Finished State psi MPa 10 in. %Unannealed 40 000 275 .
27、Annealed . . 107. Electrical Properties7.1 DC ResistanceThe dc resistance in /1000 ft of thebunch-stranded conductor shall not exceed the appropriatevalues specified in Table 5. The dc resistance in /1000 ft ofthe rope-lay bunch-stranded conductor shall not exceed theappropriate values specified in
28、Table 6 (Explanatory Note 3and Note 4).8. Test Methods8.1 CoatingTests to determine conformance of the coatingto the requirements of Specification B33 or Specification B298shall be performed on the individual wires before stranding(see 6.1.1 to 6.1.3).8.2 Tensile Strength and Elongation:8.2.1 Tests
29、to determine conformance to the tensile strengthand elongation requirements of 6.3 shall be made on thefinished stranded conductor.8.2.2 Determine tensile strength, Ts, expressed in poundsper square inch as follows:Ts5LAwhere:L = maximum load on the stranded conductor during thetension test (see Exp
30、lanatory Note 6), lbs, andA = original cross-sectional area of the stranded conductor,in.2(see 8.2.3).8.2.3 The original cross-sectional area of the stranded con-ductor shall be considered to be the cross-sectional area of theindividual wire calculated from the nominal wire diameter (seeTABLE 1 Clas
31、sification of Type B Bunch-Stranded ConductorsClass Wire Diameter, in.AConductor Sizes, AWGR 0.0025 (No. 42 AWG) 24,26,28,30,32,34S 0.0020 (No. 44 AWG) 26,28,30,32,34,36T 0.00157 (No. 46 AWG) 28,30,32,34,36,38U 0.00124 (No. 48 AWG) 30,32,34,36,38,40V 0.00099 (No. 50 AWG) 32,34,36,38,40ASufficient qu
32、antities of wires of these diameters shall be used to form conductorshaving cross-sectional areas approximately equal to the AWG conductor sizeslisted.B738 13 (2018)2Table 5 and Table 6) multiplied by the number of wires in thestranded conductor (Explanatory Note 6).8.2.4 Determine the elongation of
33、 the specimen as thepermanent increase in length, expressed in percent of theoriginal length, due to the breaking of the specimen in tension,by measurements made between the jaws of testing machine.The zero length shall be the distance between the jaws at thestart of the tension test, and shall be a
34、s near 10 in. (250 mm)as practicable. The final length shall be the distance betweenthe jaws at the time of rupture. The fracture shall be betweenthe jaws of the testing machine and not closer than 1 in. (25mm) to either jaw.8.3 ElectricalTests to determine conformance to the elec-trical resistance
35、requirements of 7.1 shall be made on thefinished stranded conductor in accordance with Test MethodB193 (Explanatory Note 3).8.4 Other RequirementsFor the purpose of calculatingmass, cross-sectional area, and so forth, the density of thecoated copper shall be taken as 8.89 g/cm3(0.32117 lb/in.3)at20C
36、 (Explanatory Note 5).8.5 Examination for Workmanship of Finished UninsulatedStranded ConductorAvisual inspection with the unaided eyeshall be performed on the outer layer of the conductor on thesupplied package. Use a white card (as a background) toascertain if any base metal is exposed through a b
37、reak in thecoating. Detection of any base metal constitutes rejection.8.6 Examination for Workmanship of Finished UninsulatedStranded ConductorA visual inspection with 10 magnifica-tion and a white background shall be performed on a conductorsample taken from the top of the supplied spool. The sampl
38、eshall be a minimum of 12 in. (30 cm) in length. The outersurface of all stranded constructions shall be examined.Detection of excessive exposed base metal due to thestranding process, such as indications along one side of thesample due to excessive localized abrasion during stranding,constitutes re
39、jection. Continuous lines or patterns of exposedbase metals constitute rejection. Small, random point failuresshall not be cause for rejection.9. Inspection9.1 Unless otherwise specified in the contract or purchaseorder, the manufacturer shall be responsible for the perfor-mance of all inspection an
40、d test requirements specified.9.2 All inspection and tests shall be made at the place ofmanufacture unless otherwise especially agreed upon betweenthe manufacturer and the purchaser at the time of purchase.9.3 The manufacturer shall afford the inspector representingthe purchaser all reasonable manuf
41、acturers facilities to satisfyhim that the material is being furnished in accordance with thisspecification.10. Product Marking10.1 The net mass, length (or lengths, and number oflengths, if more than one length is included in the package),size designation, type of conductor, purchase order number,a
42、nd any other marks required by the purchase order shall bemarked on a tag attached to the reel and, optionally, to the endof the conductor inside of the package. The same information,TABLE 2 Construction Requirements of Bunch-Stranded and Rope-Lay Bunch-Stranded ConductorsANominalArea,cmilSize,AWGCL
43、ASS R CLASS S CLASS T CLASS U CLASS VMinimum Numberof Wires 0.0025 in.in Diameter(No. 42 AWG)Minimum Numberof Wires 0.0020 in.in Diameter(No. 44 AWG)Minimum Numberof Wires 0.00157 in.in Diameter(No. 46 AWG)Minimum Numberof Wires 0.00124 in.in Diameter(No. 48 AWG)Minimum Numberof Wires 0.00099 in.in
44、Diameter(No. 50 AWG)TypeBB TypeCR Type B Type R Type B Type R Type B Type R Type B Type R2580 16 . . . 665 . . . . . .1620 18 . . . 413 . . . . . .1020 20 . 168 . 259 . . . . . .640 22 . 105 . 168 . . . . . .404 24 65 . . 105 . 168 . . . .253 26 41 . 65 . . 105 . 168 . .159 28 26 . 40 . 65 . . 105 .
45、 168100 30 16 . 25 . 40 . 65 . . 10564 32 10 . 16 . 25 . 40 . 65 .40 34 7 . 10 . 16 . 25 . 40 .25 36 . . 7 . 10 . 16 . 25 .16 38 . . . . 7 . 10 . 16 .10 40 . . . . . . 7 . 10 .AThis table shows a variety of strand constructions useful and generally adequate to meet the needs encountered. It is not i
46、ntended that the constructions listed in thistable be exclusive of other constructions that may appear durable in certain applications employing the same number of wires. The constructions shown in this table providefor a finished, noncovered, stranded conductor approximately of the area indicated.
47、When specified by the purchaser, usually to provide additional area to compensatefor draw-down during subsequent processing, the number or size of wires composing the uncovered conductor may be increased as required.BType B Bunch-Stranded Conductors.CType R Rope-Lay Bunch-Stranded Conductors.TABLE 3
48、 Classification of Type R Rope-Lay Bunch-StrandedConductorsAClass Wire Diameter, in.BConductor Sizes, AWGR 0.0025 (No. 42 AWG) 20,22S 0.0020 (No. 44 AWG) 16,18,20,22,24T 0.00157 (No. 46 AWG) 24,26U 0.00124 (No. 48 AWG) 26,28V 0.00099 (No. 50 AWG) 28,30ARope-lay bunch-stranded conductors 7 by bunch-s
49、tranded members.BSufficient quantities of wires of these diameters shall be used to form conductorshaving cross-sectional areas approximately equal to the AWG conductor sizeslisted.B738 13 (2018)3together with the manufacturers serial number, if any, and allshipping marks required by the purchaser, shall appear on theoutside of each package.11. Packaging11.1 Package sizes for conductors shall be agreed upon bythe manufacturer and the purchaser in the placing of individualorders.11.2 The conductors shall be protected against damage inordinary handling and
