1、Designation: B8 11Standard Specification forConcentric-Lay-Stranded Copper Conductors, Hard,Medium-Hard, or Soft1This standard is issued under the fixed designation B8; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of la
2、st revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This specification covers bare concentric-l
3、ay-strandedconductors made from round copper wires, either uncoated orcoated with tin, lead, or lead alloy for general use for electricalpurposes. These conductors shall be constructed with a centralcore surrounded by one or more layers of helically laid wires.NOTE 1This specification also permits c
4、onductors for use as coveredor insulated electrical conductors.NOTE 2Sealed conductors, that are intended to prevent longitudinalwater propagation and are further covered/insulated, are also permittedwithin the guidelines of this specification.1.2 For the purposes of this specification, conductors a
5、reclassified as follows (Explanatory Note 1 and Note 2):1.2.1 Class AAFor bare conductors usually used in over-head lines.1.2.2 Class AFor conductors to be covered with weather-resistant (weather-proof), slow-burning materials, and for bareconductors where greater flexibility than is afforded by Cla
6、ssAA is required.1.2.3 Class BFor conductors to be insulated with variousmaterials such as rubber, paper, varnished cloth, and so forth,and for the conductors indicated under Class A where greaterflexibility is required.1.2.4 Class C and Class DFor conductors where greaterflexibility is required tha
7、n is provided by Class B conductors.1.3 The SI values for density are regarded as the standard.For all other properties, the inch-pound values are to beregarded as standard and the SI units may be approximate.2. Referenced Documents2.1 ASTM Standards:2B1 Specification for Hard-Drawn Copper WireB2 Sp
8、ecification for Medium-Hard-Drawn Copper WireB3 Specification for Soft or Annealed Copper WireB33 Specification for Tin-Coated Soft or Annealed CopperWire for Electrical PurposesB172 Specification for Rope-Lay-Stranded Copper Con-ductors Having Bunch-Stranded Members, for ElectricalConductorsB173 Sp
9、ecification for Rope-Lay-Stranded Copper Con-ductors Having Concentric-Stranded Members, for Elec-trical ConductorsB174 Specification for Bunch-Stranded Copper Conductorsfor Electrical Conductors3B189 Specification for Lead-Coated and Lead-Alloy-Coated Soft Copper Wire for Electrical PurposesB193 Te
10、st Method for Resistivity of Electrical ConductorMaterialsB246 Specification for Tinned Hard-Drawn and Medium-Hard-Drawn Copper Wire for Electrical PurposesB263 Test Method for Determination of Cross-SectionalArea of Stranded ConductorsB354 Terminology Relating to Uninsulated Metallic Elec-trical Co
11、nductorsB787/B787M Specification for 19 Wire CombinationUnilay-Stranded Copper Conductors for Subsequent Insu-lation3. Ordering Information3.1 Orders for material under this specification shall includethe following information:3.1.1 Quantity of each size and class,3.1.2 Conductor size: circular-mil
12、area orAWG (Section 6),3.1.3 Class (see 1.2 and Table 1),3.1.4 Temper (see 13.2),3.1.5 Whether coated or uncoated; if coated, designate typeof coating (see 13.1 and 13.2),3.1.6 Details of special-purpose lays, if required (see 5.4),3.1.7 When physical tests shall be made (see Sections 7 and8),1This
13、specification is under the jurisdiction of ASTM Committee B01 onElectrical Conductors and is the direct responsibility of Subcommittee B01.04 onConductors of Copper and Copper Alloys.Current edition approved April 1, 2011. Published May 2011. Originallyapproved in 1915. Last previous edition approve
14、d in 2004 as B8 04. DOI:10.1520/B0008-11.2For 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 ASTM website.Available from Ameri
15、can Association of State Highway and TransportationOfficials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.8 Package size (see Section 15),3.1.9 Laggi
16、ng, if required (see section 15.2),3.1.10 Special package marking, if required (see section15.3), and3.1.11 Place of inspection (see Section 14).4. Joints4.1 Welds and brazes may be made in rods or in wires priorto final drawing. Joints may not be made in the finished wirescomposing hard-drawn or me
17、dium-hard-drawn Class AA con-ductors of seven wires or less. In other conductors, welds andbrazes may be made in the finished individual wires composingthe conductor, but shall not be closer together than prescribedin Table 2.5. Lay5.1 For Class AA conductors composed of less than sevenwires, the pr
18、eferred lay is 11 times the outside diameter of thecompleted conductor, but shall be not less than 8 nor more than14 times this diameter.TABLE 1 Construction Requirements of Concentric-Lay-Stranded Copper ConductorsArea ofCross-Section,cmilSize,AmericanWire GageClass AA Class A Class BAClass C Class
19、 DNumber ofWiresDiameter ofWires, milsNumber ofWiresDiameter ofWires, milsNumber ofWiresDiameter ofWires, milsNumber ofWiresDiameter ofWires, milsNumber ofWiresDiameter ofWires, mils*5 000 000 . . . 169 172.0 217 151.8 271 135.8 271 135.84 500 000 . . . 169 163.2 217 144.0 271 128.9 271 128.94 000 0
20、00 . . . 169 153.8 217 135.8 271 121.5 271 121.53 500 000 . . . 127 166.0 169 143.9 217 127.0 271 113.6*3 000 000 . . . 127 153.7 169 133.2 217 117.6 271 105.2*2 500 000 . . . 91 165.7 127 140.3 169 121.6 217 107.3*2 000 000 . . . 91 148.2 127 125.5 169 108.8 217 96.01 900 000 . . . 91 144.5 127 122
21、.3 169 106.0 217 93.61 800 000 . . . 91 140.6 127 119.1 169 103.2 217 91.1*1 750 000 . . . 91 138.7 127 117.4 169 101.8 217 89.81 700 000 . . . 91 136.7 127 115.7 169 100.3 217 88.51 600 000 . . . 91 132.6 127 112.2 169 97.3 217 85.9*1 500 000 . . . 61 156.8 91 128.4 127 108.7 169 94.21 400 000 . .
22、. 61 151.5 91 124.0 127 105.0 169 91.01 300 000 . . . 61 146.0 91 119.5 127 101.2 169 87.7*1 250 000 . . . 61 143.1 91 117.2 127 99.2 169 86.01 200 000 . . . 61 140.3 91 114.8 127 97.2 169 84.31 100 000 . . . 61 134.3 91 109.9 127 93.1 169 80.7*1 000 000 . 37 164.4 61 128.0 61 128.0 91 104.8 127 88.
23、7900 000 . 37 156.0 61 121.5 61 121.5 91 99.4 127 84.2*800 000 . 37 147.0 61 114.5 61 114.5 91 93.8 127 79.4*750 000 . 37 142.4 61 110.9 61 110.9 91 90.8 127 76.8*700 000 . 37 137.5 61 107.1 61 107.1 91 87.7 127 74.2650 000 . 37 132.5 61 103.2 61 103.2 91 84.5 127 71.5*600 000 . 37 127.3 37 127.3 61
24、 99.2 91 81.2 127 68.7550 000 . 37 121.9 37 121.9 61 95.0 91 77.7 127 65.8*500 000 . 19 162.2 37 116.2 37 116.2 61 90.5 91 74.1450 000 . 19 153.9 37 110.3 37 110.3 61 85.9 91 70.3*400 000 . 19 145.1 19 145.1 37 104.0 61 81.0 91 66.3*350 000 . 12 170.8 19 135.7 37 97.3 61 75.7 91 62.0*300 000 . 12 15
25、8.1 19 125.7 37 90.0 61 70.1 91 57.4*250 000 . 12 144.3 19 114.7 37 82.2 61 64.0 91 52.4*211 600 0000 7 173.9 7 173.9 19 105.5 37 75.6 61 58.9*167 800 000 7 154.8 7 154.8 19 94.0 37 67.3 61 52.4*133 100 00 7 137.9 7 137.9 19 83.7 37 60.0 61 46.7*105 600 0 7 122.8 7 122.8 19 74.5 37 53.4 61 41.6*83 6
26、90 1 3B167.0 7 109.3 19 66.4 37 47.6 61 37.0*66 360 2 3B148.7 7 97.4 7 97.4 19 59.1 37 42.4*52 620 3 3B132.5 7 86.7 7 86.7 19 52.6 37 37.7*41 740 4 3B118.0 7 77.2 7 77.2 19 46.9 37 33.6*33 090 5 . . . . 7 68.8 19 41.7 37 29.9*26 240 6 . . . . 7 61.2 19 37.2 37 26.6*20 820 7 . . . . 7 54.5 19 33.1 37
27、 23.7*16 510 8 . . . . 7 48.6 19 29.5 37 21.1*13 090 9 . . . . 7 43.2 19 26.2 37 18.8*10 380 10 . . . . 7 38.5 19 23.4 37 16.7*6 530 12 . . . . 7 30.5 19 18.5 37 13.3*4 110 14 . . . . 7 24.2 19 14.7 37 10.5*2 580 16 . . . . 7 19.2 19 11.7 . .*1 620 18 . . . . 7 15.2 19 9.2 . .*1 020 20 . . . . 7 12.
28、1 19 7.3 . .*640 22 . . . . 7 9.6 19 5.8 . .*404 24 . . . . 7 7.6 19 4.6 . .* The sizes of conductors that have been marked with an asterisk provide for one or more schedules of preferred series, and are commonly used in the industry. Thesizes not marked are given simply as a matter of reference and
29、 it is suggested that their use be discouraged.AFor unidirectional/unilay constructions the number of wires shown are minimum requirements.BAlthough Class AA conductors having three strands do not conform to the construction requirements of 1.1, they are listed in this table for convenience.B81125.2
30、 For Class AA conductors composed of seven wires ormore, the preferred lay of a layer of wires is 13.5 times theoutside diameter of that layer, but shall be not less than 10 normore than 16 times this diameter.5.3 For all other classes the lay of a layer of wires shall benot less than 8 nor more tha
31、n 16 times the outside diameter ofthat layer, except that for conductors composed of 37 wires ormore, this requirement shall apply only to the two outer layers.The lay of the layers other than the two outer layers shall be atthe option of the manufacturer, unless otherwise agreed upon.5.3.1 For cond
32、uctors to be used in covered or insulatedwires or cables, the lay length shall be not less than 8 nor morethan 16 times the outer diameter of the finished conductor. Forconductors of 37 wires or more, this requirement shall apply tothe wires in the outer two layers. The lay of the layers otherthan t
33、he two outer layers shall be at the option of themanufacturer, unless otherwise agreed upon.5.4 Other lays for special purposes shall be furnished byspecial agreement between the manufacturer and the purchaser(Explanatory Note 3).5.5 The direction of lay of the outer layer shall be left-hand,and for
34、 conductors having a nominal cross-sectional area largerthan No. 8 AWG, shall be reversed in successive layers, unlessotherwise specified by the purchaser.5.5.1 For conductors to be used in covered or insulatedwires or cables, the direction of lay of the outer layer shall beleft hand and shall be re
35、versed in successive layers, unidirec-tional, or unilay, unless otherwise agreed upon.6. Construction6.1 The areas of cross section, numbers, and diameters ofwires in the various classes of concentric-lay-stranded conduc-tors shall conform to the requirements prescribed in Table 1(Explanatory Notes
36、3 and 10).6.2 The diameters of the wires listed in Table 1 are nominal.Where “combination strand” is required in order to insulate theconductor properly (strands in the outer layer having a largerdiameter than those in the inner layers) the diameters shall besubject to a tolerance of 65 %, provided
37、that the area of crosssection after stranding is in accordance with Section 11.6.3 Where compressed stranding is required in order toinsulate the conductor properly, one or more layers of anystranded conductor consisting of 7 wires or more may beslightly compressed, thereby reducing the outside diam
38、eter ofthe conductor to the nominal values shown in Table 3, providedthat the area of cross section after stranding is in accordancewith Section 11.7. Physical and Electrical Tests of Conductors Strandedof Soft Wires7.1 Tests for the electrical properties of wires composingconductors made from soft
39、or annealed copper wire, bare orcoated, shall be made before stranding.7.2 Tests for the physical properties of soft or annealedcopper wire, bare or coated, may be made upon the wiresbefore stranding or upon wires removed from the completestranded conductor, but need not be made upon both. Care shal
40、lbe taken to avoid mechanical injury to wire removed from theconductor for the purpose of testing.7.3 The physical properties of wire when tested beforestranding shall conform to the applicable requirements of 13.2.7.4 The physical properties of wires removed from thecompleted stranded conductor sha
41、ll be permitted to vary fromthe applicable requirements of 13.2 by the following amounts(Explanatory Note 4):7.4.1 Average of Results Obtained on All Wires TestedTheminimum elongation required shall be reduced in numericalvalue 5 (for example, from 30 to 25 %) from the numericalrequirements for the
42、wire before stranding.7.4.2 Results Obtained on Individual WiresThe elonga-tion of individual wires shall be reduced in numerical value 15from the minimum requirements before stranding (that is, 10 inaddition to the 5 allowed in 7.4.1), but in no case shall theelongation of any individual wire be le
43、ss than 5 %.7.5 In the event that the requirements prescribed in 7.4.2 aremet but those prescribed in 7.4.1 are not met, a retest shall bepermitted wherein all wires of the conductor shall be tested forthe purpose of final determination of conformance to 7.4.7.6 Elongation tests to determine complia
44、nce shall not bemade on the conductor as a unit.7.7 If a tinning, lead-coating, or lead-alloy-coating test isrequired, it shall be made on the wires prior to stranding.8. Physical and Electrical Tests of Conductors Strandedof Hard-Drawn or Medium-Hard-Drawn Wires8.1 Tests for the physical and electr
45、ical properties of wirescomposing conductors made from hard-drawn or medium-hard-drawn wires, uncoated or coated, shall be made before butnot after stranding.8.2 At the option of the purchaser, tension and elongationtests on hard-drawn and medium-hard-drawn wires, uncoatedor coated, before stranding
46、 may be waived, and the completedhard-drawn and medium-hard-drawn conductors may be testedas a unit.The breaking strength of the bare conductors so testedshall be at least 90 % of the total of the specified minimumTABLE 2 Minimum Distance Between Joints in the Completed ConductorNumber of Wires inCo
47、nductorHard or Medium-Hard SoftClass AA Class A Class B Class C Class D All Classes3 none permitted . . . . 1 ft7 none permitted 50 ft 50 ft . . 1 ft12 50 ft 50 ft . . . 1 ft19 50 ft 50 ft 50 ft 50 ft . 1 ft20 to 36 50 ft 50 ft 50 ft 50 ft . 1 ft in a layerA37 to 60 25 ft 25 ft 25 ft 25 ft 1 ft in a
48、 layerA61 and over . 5 ft 5 ft 5 ft 5 ft 1 ft in a layerAAExcept as indicated, the limitations apply to closeness of joints throughout the completed conductor.B8113TABLE 3 Diameters, Areas, and Mass of Concentric-Lay-Stranded Copper Conductors (Explanatory Note 8)Size of Conductor,Nominal Conductor
49、Diameter, in.AArea, in.2Massdc Resistance at20CBConcentric Strandcmil or AWG numbers mm2Class AA Class A Class BReverseConcentricCompressedClass BDiameter,in.UnilayCom-pressedCDiameter,in.lbs/1000 ft kg/km V/1000 ft V/km*5 000 000 cmil 2530 . 2.580 2.581 . . 3.927 15 890 23 649 0.00218 0.007154 500 000 cmil 2280 . 2.448 2.448 . . 3.534 14 300 21 283 0.00242 0.007944 000 000 cmil 2030 . 2.307 2.309 . . 3.142 12 590 18 738 0.00270 0.008863 500 000 cmil 1770 . 2.158 2.159 . . 2.749 11 020 16 401 0.00308 0.0101*3 000 000 cmil 1520 . 1.998 1.998 . . 2.356 9 353 13 920 0.00356 0.
