1、Designation: B 258 02 (Reapproved 2008)Standard Specification forStandard Nominal Diameters and Cross-Sectional Areas ofAWG Sizes of Solid Round Wires Used as ElectricalConductors1This standard is issued under the fixed designation B 258; the number immediately following the designation indicates th
2、e year 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.This standard has been approved for use by agencies of the Dep
3、artment of Defense.1. Scope1.1 This specification prescribes standard nominal diam-eters and cross-sectional areas of American Wire Gage (AWG)sizes of solid round wires, used as electrical conductors, andgives equations and rules for the calculation of standardnominal mass and lengths, resistances,
4、and breaking strengthsof such wires (Explanatory Note 1).1.2 The values stated in inch-pound or SI units are to beregarded separately as standard. Each system shall be usedindependently of the other. Combining values of the twosystems may result in nonconformance with the specification.For conductor
5、 sizes designated by AWG or kcmil sizes, therequirements in SI units have been numerically converted fromthe corresponding values stated or derived, in inch-pound units.For conductor sizes designated by SI units only, the require-ments are stated or derived in SI units.1.2.1 For density, resistivity
6、 and temperature, the valuesstated in SI units are to be regarded as standard.2. Referenced Documents2.1 ASTM Standards:2A 111 Specification for Zinc-Coated (Galvanized) “Iron”Telephone and Telegraph Line WireA 326 Specification for Zinc-Coated (Galvanized) HighTensile Steel Telephone and Telegraph
7、Line Wire3B1 Specification for Hard-Drawn Copper WireB2 Specification for Medium-Hard-Drawn Copper WireB3 Specification for Soft or Annealed Copper WireB9 Specification for Bronze Trolley WireB33 Specification for Tinned Soft or Annealed CopperWire for Electrical PurposesB47 Specification for Copper
8、 Trolley WireB 105 Specification for Hard-Drawn Copper Alloy Wiresfor Electric ConductorsB 189 Specification for Lead-Coated and Lead-Alloy-Coated Soft Copper Wire for Electrical PurposesB 193 Test Method for Resistivity of Electrical ConductorMaterialsB 227 Specification for Hard-Drawn Copper-Clad
9、SteelWireB 230/B 230M Specification for Aluminum 1350H19Wire for Electrical PurposesB 314 Specification for Aluminum 1350 Wire for Commu-nication Cable3B 396 Specification for Aluminum-Alloy 5005-H19 Wirefor Electrical Purposes3B 398/B 398M Specification for Aluminum-Alloy 6201-T81 Wire for Electric
10、al PurposesB 415 Specification for Hard-Drawn Aluminum-Clad SteelWireB 609/B 609M Specification for Aluminum 1350 RoundWire, Annealed and Intermediate Tempers, for ElectricalPurposesB 800 Specification for 8000 Series Aluminum Alloy Wirefor Electrical PurposesAnnealed and Intermediate Tem-persE29 Pr
11、actice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsF 205 Test Method for Measuring Diameter of Fine Wire byWeighing3. Standard Reference Temperature3.1 For the purpose of this specification, all wire dimensionsand properties shall be considered as occurring a
12、t the interna-tionally standardized reference temperature of 20C (68F).1This specification is under the jurisdiction of ASTM Committee B01 onElectrical Conductors and is the direct responsibility of Subcommittee B01.02 onMethods of Test and Sampling Procedure.Current edition approved Sept. 1, 2008.
13、Published September 2008. Originallyapproved in 1951. Last previous edition approved in 2002 as B 258 02.2For 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 standar
14、ds Document Summary page onthe ASTM website.3Withdrawn1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Standard Rules for Rounding4.1 All calculations for the standard nominal dimensionsand properties of solid round wires shall be
15、rounded in the finalvalue only, in accordance with rounding method of PracticeE29.5. Standard Nominal Diameters5.1 Standard nominal diameters of AWG sizes of solidround wires shall be calculated in accordance with the conven-tional mathematical law of the American Wire Gage (seeExplanatory Note 1) a
16、nd in accordance with Section 4.5.2 For wire sizes 4/0 to 44 AWG, inclusive, nominaldiameters shall be expressed in no more than four significantfigures but in no case closer than the nearest 0.1 mil (0.0001in.).5.3 For wire sizes 45 to 56 AWG, inclusive, nominaldiameters shall be expressed to the n
17、earest 0.01 mil (0.00001in.).5.4 The standard nominal diameters expressed in mils havebeen calculated in accordance with these rules and are given inTable 1 for convenient reference (Explanatory Note 2).6. Standard Nominal Cross-Sectional Areas6.1 Standard nominal cross-sectional areas in circular m
18、ilsand square millimetres shall be calculated in accordance withthe following equations and shall be rounded in accordancewith Section 4 to the same number of significant figures as usedin expressing the standard diameters, but in no case to less thanthree significant figures:Area, cmil 5 d2Area, mm
19、25 d23 5.067 3 1024where:d = diameter of the wire in mils as given in Table 1.Standard nominal cross-sectional areas in circular mils andsquare millimetres have been calculated in accordance with theforegoing rules and are given in Table 1 for convenientreference.7. Rules for Calculations Involving
20、Mass and Length7.1 Standard nominal mass and lengths shall be calculatedfrom the standard wire diameters specified in Table 1,inaccordance with the following equations. They shall berounded in the final value only, in accordance with Section 4,to the same number of significant figures as used in exp
21、ressingthe standard diameters, but in no case to less than threesignificant figures:W 5 d23d30.34049 3 1023L 5 1/d2! 3 1/d! 3 2.9369 3 106where:W = mass, lb/1000 ft,d = diameter of the wire in mils as given in Table 1,d = density of the wire material at 20C in g/cm3as givenin Table 2, andL = length,
22、 ft/lb.TABLE 1 Standard Nominal Diameters and Cross-Sectional Areas of AWG Sizes of Solid Round Wires at 20CSize Diameter Cross-Sectional Area Size Diameter Cross-Sectional AreaAWG mils mm cmils mm2AWG mils mm cmils mm24/0 460.0 11.684 211 600 107.2 29 11.3 0.287 128 0.06473/0 409.6 10.404 167 800 8
23、5.0 30 10.0 0.254 100 0.05072/0 364.8 9.26 133 100 67.4 31 8.9 0.226 79.2 0.04011/0 324.9 8.25 105 600 53.5 32 8.0 0.203 64.0 0.03241 289.3 7.35 83 690 42.4 33 7.1 0.180 50.4 0.02552 257.6 6.54 66 360 33.6 34 6.3 0.160 39.7 0.02013 229.4 5.82 52 620 26.7 35 5.6 0.142 31.4 0.01594 204.3 5.19 41 740 2
24、1.1 36 5.0 0.127 25.0 0.01275 181.9 4.62 33 090 16.8 37 4.5 0.114 20.2 0.01036 162.0 4.11 26 240 13.3 38 4.0 0.102 16.0 0.008117 144.3 3.67 20 820 10.6 39 3.5 0.0890 12.2 0.006218 128.5 3.26 16 510 8.37 40 3.1 0.0787 9.61 0.004879 114.4 2.91 13 090 6.63 41 2.8 0.0711 7.84 0.0039710 101.9 2.59 10 380
25、 5.26 42 2.5 0.0635 6.25 0.0031711 90.7 2.30 8 230 4.17 43 2.2 0.0559 4.84 0.0024512 80.8 2.05 6 530 3.31 44 2.0 0.0508 4.00 0.0020313 72.0 1.83 5 180 2.63 45 1.76 0.0447 3.10 0.0015714 64.1 1.63 4 110 2.08 46 1.57 0.0399 2.46 0.0012515 57.1 1.45 3 260 1.65 47 1.40 0.0356 1.96 0.00099316 50.8 1.29 2
26、 580 1.31 48 1.24 0.0315 1.54 0.00077917 45.3 1.15 2 050 1.04 49 1.11 0.0282 1.23 0.00062418 40.3 1.02 1 620 0.823 50 0.99 0.0252 0.980 0.00049719 35.9 0.904 1 290 0.653 51 0.88 0.0224 0.774 0.00039220 32.0 0.813 1 020 0.519 52 0.78 0.0198 0.608 0.00030821 28.5 0.724 812 0.412 53 0.70 0.0178 0.490 0
27、.00024822 25.3 0.643 640 0.324 54 0.62 0.0158 0.384 0.00019523 22.6 0.574 511 0.259 55 0.55 0.0140 0.302 0.00015324 20.1 0.511 404 0.205 56 0.49 0.0125 0.240 0.00012225 17.9 0.455 320 0.16226 15.9 0.404 253 0.12827 14.2 0.361 202 0.10228 12.6 0.320 159 0.0804B 258 02 (2008)28. Rules for Calculations
28、 Involving Resistivity8.1 Standard nominal resistances and other values derivedfrom the resistivity units shall be calculated from the standardwire diameters specified in Table 1 in accordance with thefollowing equations. All values so derived shall be rounded inthe final value only, in accordance w
29、ith Section 4, to the samenumber of significant figures as used in expressing the standarddiameters, but in no case to less than three significant figures:D2c resistance at 20C, V/1000 ft 5 r/d23d!# 3 105.35D2c resistance at 20C, V/lb 5 r/d23 d4!# 3 0.30940 3 106Length at 20C, ft/V5d23d!/r 3 9.4924M
30、ass at 20C, lb/V5d23 d4!/r 3 3.2321 3 1026where:d = diameter of the wire in mils as given in Table 1,r = resistivity of the wire material at 20C in Vlb/mile2asgiven in Table 2 (Explanatory Note 3), andd = density of the wire material at 20C in g/cm3as givenin Table 2.9. Rules for Calculating Rated S
31、trength9.1 Standard rated strengths shall be calculated from thestandard wire diameters specified in Table 1 in accordance withthe following equation and shall be rounded in the final valueonly, in accordance with Section 4, to the same number ofsignificant figures as used in expressing the standard
32、 diameters,but in no case to less than three significant figures:Rated strength, lb 5 d23 T 3 0.7854 3 1026where:d = diameter of the wire in mils as given in Table 1, andTABLE 2 Density and Resistivity of Electrical Conductor MaterialsMaterialDensity, d,at20C, g/cm3ResistivityA, r,at20C, V lb/mile2M
33、aterialDensity,d,at20C, g/cm3Resistivity, r,at20C V lb/mile2Copper (Specifications B1, B2, B Aluminum-Clad Steel (Specification 6.59 31913, B33, B47and B 189), B 415)Volume Conductivity, %IACS:Copper-Clad Steel (SpecificationB 227):100 8.89 875.2097.66 8.89 896.15 Grade 30 HS 8.15 272897.16 8.89 900
34、.77 Grade 30 EHS 8.15 272896.66 8.89 905.44 Grade 40 8.15 204596.16 8.89 910.15 Grade 40 EHS 8.15 204594.16 8.89 929.52 Galvanized Steel (Telephone and93.15 8.89 939.51 Telegraph) (Specification ABronze (Specification B9): 111):Class A 8.89 2188 Class A Coating:Class B 8.89 1346 Grade EBB (Non-Coppe
35、r 7.78 5000Class C 8.89 1094 Bearing)Copper Alloys (Specification B Grade BB (Copper Bearing) 7.78 5800105B): Grade BB (Non-Copper 7.78 5600Grade 8.5 8.78 10 169 Bearing)Grade 13 8.78 6649 Class B Coating:Grade 15 8.54 5605 Grade EBB (Non-Copper 7.78 4900Grade 20 8.89 4376 Bearing)Grade 30 8.89 2917
36、 Grade BB (Copper Bearing) 7.78 5600Grade 40 8.89 2188 Grade BB (Non-Copper 7.78 5450Grade 55 8.89 1591 Bearing)Grade 65 8.89 1346 Class C Coating:Grade 74 8.89 1183 Grade EBB (Non-Copper 7.78 4800Grade 80 8.89 1094 Bearing)Grade 85 8.89 1030 Grade BB (Copper Bearing) 7.78 5400Aluminum, 1350 (Specif
37、ications B Grade BB (Non-Copper 7.78 5300230/B 230M, B 314, andB 609/B 609M),Bearing)Volume Conductivity, %IACS:Galvanized Steel (Telephone andTelegraph) (SpecificationA 326):61.8 2.705 430.9161.2 2.705 435.1361.0 2.705 436.56 Class A Coating:Aluminum Alloys (Specifications B Grade 85 7.83 5800396 a
38、nd B 398/B 398M) Class B Coating:Alloy 5005H19 2.70 496.84 Grade 135 7.83 6500Alloy 6201T81 2.69 504.43 Grade 85 7.80 5600Aluminum Alloy 8000 Series Grade 135 7.80 6300(Specification B 800) Class C Coating:Volume Conductivity, %IACS:Grade 85 7.77 540061.0 2.71 437.36 Grade 135 7.77 6100ATo convert f
39、rom Vlb/mile2to Vg/m2multiply by 5710.0. See Table 1 in Test Method B 193.BVarious compositions are permitted for some of the grades in Specification B 105 and the density value may not apply to all materials supplied to this specification.In case of doubt, the density value should be determined or
40、obtained from the manufacturer.B 258 02 (2008)3T = tensile strength, psi, applicable to the wire material,temper, and size, for which reference should be madeto the specifications which cover the material.10. Tolerances10.1 The standard dimensions given in Table 1 and thecalculated values for mass,
41、resistances, and rated strengthsobtained by the use of the formulas included in this specifica-tion are all nominal values. This specification is not concernedwith quantitative values of tolerances per se, but it is contem-plated that the standard nominal wire dimensions specified inTable 1, and the
42、 properties derived therefrom, shall be madesubject to tolerances as indicated in either the individualspecifications applicable to the wires of various materials andtempers or as may be mutually agreed by the manufacturer andthe purchaser.EXPLANATORY NOTESNOTE 1Except for certain classes of wire products, the AmericanWire Gage (formerly known as the Brown or through the ASTM website(www.astm.org).4NBS Handbook 100, Nat. Institute of Standards and Technology, , is sold by theNational Technical Information Service, 5285 Port Royal Road, Springfield, VA22161.B 258 02 (2008)5
