1、Designation: B738 03 (Reapproved 2008)B738 13Standard 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
2、oforiginal 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-la
3、y bunch-stranded conductors made from round copper wires finerthan No. 40 AWG with diameters less than 0.0031 in. (.078 mm), either coated or uncoated with tin or silver, for use as electricalconductors. (Explanatory Note 1).1.2 The values (SI units) for density and temperature are regarded as the s
4、tandard. For all other properties the inch-poundvaluesstated in inch-pound units are to be regarded as standard, and the SI units may be approximate. standard. The values givenin parentheses are mathematical conversions to SI units that are provided for information only and are not considered standa
5、rd.1.2.1 ExceptionsThe SI values for density and temperature are to be regarded as standard.2. Referenced Documents2.1 ASTM Standards:2B33 Specification for Tin-Coated Soft or Annealed Copper Wire for Electrical PurposesB49 Specification for Copper Rod Drawing Stock for Electrical PurposesB172 Speci
6、fication for Rope-Lay-Stranded Copper Conductors Having Bunch-Stranded Members, for Electrical ConductorsB174 Specification for Bunch-Stranded Copper Conductors for Electrical ConductorsB193 Test Method for Resistivity of Electrical Conductor MaterialsB258 Specification for Nominal Diameters and Cro
7、ss-Sectional Areas of AWG Sizes of Solid Round Wires Used as ElectricalConductorsB298 Specification for Silver-Coated Soft or Annealed Copper WireB354 Terminology Relating to Uninsulated Metallic Electrical Conductors3. Classification3.1 For the purposes of this specification, the following classifi
8、cations 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 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 TS
9、tranded 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 50 AWG (0.00099).3.2 Detailed information on Type B Conductors is found in Table 1 and Table 2. Detailed information on Type R Conductorsis foun
10、d in Table 3 and Table 2.1 This specification is under the jurisdiction of ASTM Committee B01 on Electrical Conductors and is the direct responsibility of Subcommittee B01.04 on Conductorsof Copper and Copper Alloys.Current edition approved April 1, 2008April 1, 2013. Published May 2008April 2013. O
11、riginally approved in 1984. Last previous edition approved in 20032008 asB738 03.B738 03 (2008). DOI: 10.1520/B0738-03R08.10.1520/B0738-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume
12、information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequate
13、ly depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
14、 PA 19428-2959. United States14. Ordering Information4.1 Orders for materials under this specification shall include the following information:4.1.1 Quantity of 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
15、 Whether coated or uncoated; if coated, designate type of coating (6.1); if silver coated, the minimum thickness of silver(6.1.2), and whether tarnish protection is 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
16、size (11.1),4.1.9 Special package marking, if required (Section 10), and4.1.10 Place of inspection (Section 9).4.2 In addition, Supplementary Requirements shall apply only when specified by the purchaser in the inquiry, contract, orpurchase order for direct procurement by agencies of the U.S. Govern
17、ment.5. Materials and Manufacture5.1 The material shall be copper of such quality and purity that the finished product shall have the properties and characteristicsdescribed in this specification. Material meeting the requirements of Specification B49 is such a material.5.2 Construction:5.2.1 Cross-
18、Sectional AreaThe cross-sectional area, number, and diameter of wires for a variety of strand constructions ingeneral use are shown in Table 2.5.2.2 SeparatorsIf a separator is required to be furnished with the conductor, it shall be specified by the purchaser at the timeof the order as to the requi
19、rements for the kind and thickness of material and its application details.5.2.3 Joints:5.2.3.1 Necessary joints in wires shall be made in accordance with accepted commercial practice.5.2.3.2 Joints shall be so constructed and so disposed throughout the conductor that the diameter or configuration o
20、f thecompleted conductor is not substantially affected, and that the flexibility of the completed conductor is not adversely affected.5.2.4 Lay:5.2.4.1 Conductors of the same size and description furnished on one order shall have the same lay.5.2.4.2 The direction of the lay of bunch-stranded conduc
21、tors shall be at the option of the manufacturer unless otherwisespecified by the purchaser.5.2.4.3 Unless otherwise specified by the purchaser, the length of the lay of bare or coated bunch-stranded conductors shallconform to the requirements of Table 4.5.2.4.4 The direction of the lay of the outer
22、layer of rope-lay stranded conductors shall be lefthand, unless otherwise specifiedby the purchaser.5.2.4.5 The length of the lay of the outer layer of rope-lay stranded conductors shall be not less than 8 or more than 16 timesthe outside diameter of the completed conductor. The length of the lay of
23、 the wires composing the bunch-stranded members shallbe not more than 30 times the diameter of the member.6. Physical Properties6.1 Wire CoatingWhen coated, the coating of the wires of the stranded conductor, before stranding, shall conform to therequirements of 6.1.1 or 6.1.2.6.1.1 Tin coating shal
24、l conform to the coating requirements of Specification B33.6.1.2 Silver coating shall conform to the minimum thickness requirements of the purchase document. Minimum thickness shallbe determined using the method for determining plating thickness described in Specification B298.TABLE 1 Classification
25、 of Type B Bunch-Stranded ConductorsClass Wire Diameter, in.A Conductor 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) 32,34,36,38,40A Sufficient quantities
26、 of wires of these diameters shall be used to form conductorshaving cross-sectional areas approximately equal to the AWG conductor sizeslisted.B738 1326.1.3 The finished diameter and mass of the coated wires used shall be substantially equal to those of the uncoated wires of thesame class.6.2 Temper
27、Unless otherwise specified, all coated conductors shall be furnished in the annealed temper. Uncoated conductorsmay be furnished either annealed or unannealed as ordered (see 4.1.6).NOTE 1The term unannealed as used in this specification means cold-worked conductor as produced on commercial wire-dra
28、wing machines.6.3 Tensile Strength and ElongationThe stranded conductor, in its finished form, shall conform to the following:Tensile Strength, min. Elongation, min,Finished State psi MPa 10 in. %UnannealedAnnealed40 000.275.10Unannealed 40 000 275 .Annealed . . 107. Electrical Properties7.1 DC Resi
29、stanceThe dc resistance in /1000 ft of the bunch-stranded conductor shall not exceed the appropriate valuesspecified in Table 5. The dc resistance in /1000 ft of the rope-lay bunch-stranded conductor shall not exceed the appropriatevalues specified in Table 6 (Explanatory Note 3 and Note 4).8. Test
30、Methods8.1 CoatingTests to determine conformance of the coating to 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:TABLE 2 Construction Requirements of Bunch-Stranded and R
31、ope-Lay Bunch-Stranded ConductorsANominalArea,cmilSize,AWGCLASS 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.
32、in Diameter(No. 48 AWG)Minimum Numberof Wires 0.00099 in.in Diameter(No. 50 AWG)TypeB B TypeC R 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 . . .
33、.253 26 41 . 65 . . 105 . 168 . .159 28 26 . 40 . 65 . . 105 . 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 .A This This table shows a variety of strand constructions usef
34、ul and generally adequate to meet the needs encountered. It is not intended that the constructions listed inthis table be exclusive of other constructions that may appear durable in certain applications employing the same number of wires. The constructions shown in this tableprovide for a finished,
35、noncovered, stranded conductor approximately of the area indicated. When specified by the purchaser, usually to provide additional area tocompensate for draw-down during subsequent processing, the number or size of wires composing the uncovered conductor may be increased as required.B Type B Bunch-S
36、tranded Conductors.C Type R Rope-Lay Bunch-Stranded Conductors.TABLE 3 Classification of Type R Rope-Lay Bunch-StrandedConductorsAClass Wire Diameter, in.B Conductor 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 0.0
37、0099 (No. 50 AWG) 28,30A Rope-lay bunch-stranded conductors 7 by bunch-stranded members.B Sufficient quantities of wires of these diameters shall be used to form conductorshaving cross-sectional areas approximately equal to the AWG conductor sizeslisted.B738 1338.2.1 Tests to determine conformance t
38、o the tensile strength and elongation requirements of 6.3 shall be made on the finishedstranded conductor.8.2.2 Determine tensile strength, Ts, expressed in pounds per square inch as follows:Ts 5 LAwhere:L = maximum load on the stranded conductor during the tension test (see Explanatory Note 6), lbs
39、, andA = original cross-sectional area of the stranded conductor, in.2 (see 8.2.3).where:L = maximum load on the stranded conductor during the tension test (see Explanatory Note 5), lbs, andA = original cross-sectional area of the stranded conductor, in.2/in. (see 8.2).TABLE 4 Maximum Length of Lay
40、for Bunch-Stranded ConductorsSize, AWG Nominal Diameter Nominal Area Maximum Length of Layin. (mm) cmil (mm2) in. (mm)24 0.024 (0.61) 404 (0.20) 0.70 (18)26 0.019 (0.48) 253 (0.13) 0.60 (15)28 0.015 (0.38) 159 (0.081) 0.50 (13)30 0.012 (0.30) 100 (0.051) 0.40 (10)32 0.009 (0.23) 64 (0.032) 0.30 (7.6
41、)34 0.007 (0.18) 40 (0.020) 0.25 (6.4)36 0.006 (0.15) 25 (0.013) 0.20 (5.1)38 0.005 (0.13) 16 (0.0081) 0.15 (3.8)40 0.004 (0.10) 10 (0.0051) 0.13 (3.3)TABLE 5 DC Ohmic Resistance Per 1000 Ft. of Type B Bunch-Stranded ConductorsSize DesignationsConductor ConstructionA Calculated TotalCross-SectionalA
42、rea cmilDC Resistance at 20C, /1000 ft, max.BNumber ofWiresCNominal Diameterof Each Wire, in.Annealed Bare orSilver CoatedDAnnealed TinCoatedEUnannealedBare24-65 65 0.0025 406 28.3 30.4 29.426-41 41 0.0025 256 44.9 48.2 46.726-65 65 0.0020 260 45.2 48.5 47.028-26 26 0.0025 163 70.8 76.0 73.628-40 40
43、 0.0020 160 73.5 78.9 76.428-65 65 0.00157 160 71.8 . 74.630-16 16 0.0025 100 115.0 123.4 119.630-25 25 0.0020 100 117.5 126.2 122.230-40 40 0.00157 98.6 116.6 . 121.330-65 65 0.00124 99.9 115.0 . 119.632-10C 10 0.0025 62.5C 184.0 197.5 191.332-16 16 0.0020 64 183.7 197.2 191.032-25C 25 0.00157 61.6
44、C 186.6 . 194.032-40C 40 0.00124 61.5C 187.0 . 194.432-65 65 0.00099 63.7 180.5 . 187.734-7 7 0.0025 43.8 262.8 281.8 273.334-10 10 0.0020 40 293.8 315.5 305.634-16 16 0.00157 39.4 291.6 . 303.234-25C 25 0.00124 38.4C 299.1 . 311.134-40 40 0.00099 39.2 293.3 . 305.036-7 7 0.0020 28 419.8 450.6 436.5
45、36-10 10 0.00157 24.6 466.5 . 485.136-16 16 0.00124 24.6 467.4 . 486.036-25 25 0.00099 24.5 469.3 . 488.038-7 7 0.00157 17.3 666.4 . 693.038-10C 10 0.00124 15.4C 747.8 . 777.738-16 16 0.00099 15.7 733.2 . 762.540-7 7 0.00124 10.8 1068.3 . 1111.040-10 10 0.00099 9.8 1173.2 . 1220.0A See Table 2 for c
46、onstruction requirements or bunch-stranded conductors.B See Explanatory Note 4.C Bunch.D The cross-sectional areas of these conductor-size designations deviate by more than 2 % from the nominal areas of the standardAWG sizes as defined in SpecificationB258.E Tin-coated wire is not available at this
47、time on wire diameters smaller than .0020 (44 AWG).B738 1348.2.3 The original cross-sectional area of the stranded conductor shall be considered to be the cross-sectional area of theindividual wire calculated from the nominal wire diameter (see Table 5 and Table 6) multiplied by the number of wires
48、in thestranded conductor (Explanatory Note 6).8.2.4 Determine the elongation of the specimen as the permanent increase in length, expressed in percent of the original length,due to the breaking of the specimen in tension, by measurements made between the jaws of testing machine. The zero length shal
49、lbe the distance between the jaws at the start of the tension test, and shall be as near 10 in. (250 mm) as practicable. The final lengthshall be the distance between the jaws at the time of rupture. The fracture shall be between the jaws of the testing machine andnot closer than 1 in. (25 mm) to either jaw.8.3 ElectricalTests to determine conformance to the electrical resistance requirements of 7.1 shall be made on the finishedstranded conductor in accordance with Test Method B193 (Explanatory Note 3).8.4 Other RequirementsFor the purpose of calculat
