1、Designation: B 958 08Standard Specification forExtra-High-Strength and Ultra-High-Strength Class AZinc5% Aluminum-Mischmetal Alloy-Coated Steel CoreWire for Use in Overhead Electrical Conductors1This standard is issued under the fixed designation B 958; the number immediately following the designati
2、on indicates the 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.1. Scope1.1 This specification covers round, ex
3、tra-high-strength, andultra-high-strength, Class A coated zinc5 % aluminum-mischmetal (Zn5AlMM) alloy-coated, steel core wire foruse in Overhead Electrical Conductors.1.2 This specification covers wire of diameter from 0.0500to 0.1900 in. inclusive or 1.27 to 4.82 mm inclusive .1.3 The values stated
4、 in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 This
5、 standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents
6、2.1 ASTM Standards:2A 90/A 90M Test Method for Weight Mass of Coating onIron and Steel Articles with Zinc or Zinc-Alloy CoatingsA 370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA 751 Test Methods, Practices, and Terminology forChemical Analysis of Steel ProductsB 193 Test Me
7、thod for Resistivity of Electrical ConductorMaterialsB 750 Specification for GALFAN (Zinc-5 % Aluminum-Mischmetal) Alloy in Ingot Form for Hot-Dip CoatingsE 1277 Test Method for Chemical Analysis of Zinc-5 %Aluminum-MischmetalAlloys by ICP Emission Spectrom-etryE29 Practice for Using Significant Dig
8、its in Test Data toDetermine Conformance with Specifications2.2 Other Standard:GF-1 Standard Practice for Determination of Cerium andLanthanum Compositions in GalfanAlloy (5 %Al-0.04 %La- 0.04 % Ce-Bal SHG Zn)33. Terminology3.1 Abbreviations:3.1.1 MMmischmetal3.1.2 Zn5AlMMzinc5% aluminum mischmetal
9、alloy3.2 Definitions of Terms Specific to This Standard:3.3 Lot, nUnless otherwise specified in the contract ororder, a lot shall consist of all coils of wire of the samediameter and unit lengths submitted for inspection at the sametime.3.4 Product Code, nDefines product coating type, coatingclass,
10、and strength grade.Extra High Strength Grade Zn5AlMM, Class A Coated,use Code MA4.Ultra High Strength Grade Zn5AlMM, Class A Coated,use Code MA5.4. Ordering Information4.1 Orders for material under this specification shall includethe following information:4.1.1 Quantity of each size,4.1.2 Wire diame
11、ter in inches or millimeter (Section 13),4.1.3 Certification, if required (Section 18),4.1.4 Test report, if required (Section 18), and4.1.5 Package Size (Section 19).4.1.6 Product Code1This test method is under the jurisdiction of ASTM Committee B01 onElectrical Conductors and is the direct respons
12、ibility of Subcommittee B01.05 onConductors of Ferrous Metals.Current edition approved Nov. 1, 2008. Published December 2008.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
13、refer to the standards Document Summary page onthe ASTM website.3Available from the International Lead Zinc Research Organization (ILZRO),1822 NC Highway 54 East, Suite 120, Durham NC 27713, http:/www.ilzro.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA
14、19428-2959, United States.5. Materials and Manufacture5.1 The base metal shall be steel produced by the open-hearth, electric furnace, or basic oxygen process.5.2 The wire shall be cold drawn and coated withZn5AlMM alloy to produce the desired properties.6. Chemical Composition6.1 The steel shall co
15、nform to the requirements prescribedin Table 1.6.2 Chemical analysis of the steel shall be conducted inaccordance with Test Methods, Practices, and TerminologyA 751.6.3 The ingot form of zinc-5 % aluminum-mischmetal alloyshall conform to Specification B 750.6.3.1 For a two-step coating operation whe
16、re the firstcoating is zinc (hot-dip galvanized or electro-galvanized), thefinal bath may have an aluminum content of up to 7.2 %, toprevent depletion of the aluminum content of the bath.6.3.2 Method of Coating Material AnalysisRefer toSpecification B 750.7. Tensile Test7.1 The Zn5AlMM-coated steel
17、core wire shall conformto the tensile and elongation requirements prescribed in Table2, Table 3, Table 4,orTable 5 depending on which strengthgrade and unit base ordered.7.2 Tensile tests shall be conducted in accordance with TestMethods and Definitions A 370, using the initial settings fordetermini
18、ng stress at 1 % extension given in Table 6 or Table7 of this specification.7.3 Test Specimens The test specimens shall be free ofbends or kinks other than the curvature resulting from the usualcoiling operations. Any hand straightening necessary to permitinsertion of the specimen in the jaws of the
19、 testing machineshall be performed by drawing between wood blocks or bysome other equally satisfactory means.7.4 The nominal diameter requested shall be used to deter-mine the applicable strength specification from the tables.8. Wrap Test8.1 The material, as represented by the test specimens, shalln
20、ot fracture when the Zn5AlMM alloy-coated wire iswrapped at a rate not exceeding 15 turns/min in a close helixof at least eight turns around a cylindrical mandrel with adiameter equal to four times the specified diameter of the wireunder test, 6 5%.9. Coating Test9.1 The Zn5AlMM alloy-coated wire sh
21、all conform to thecoating requirements prescribed in Table 8 or Table 9.9.2 The coating test shall be conducted in accordance withTest Method A 90/A 90M.10. Adherence of Coating Test10.1 The Zn5AlMM alloy-coated wire shall be capable ofbeing wrapped in a close helix at a rate not exceeding 15turns/m
22、in around a cylindrical mandrel having a diameter asprescribed in Table 10 or Table 11, without cracking or flakingthe coating to such an extent that any Zn5AlMM alloy canbe removed by rubbing with the bare fingers.11. Joints11.1 No joints shall be made in the finished wire.TABLE 1 Chemical Requirem
23、entsElement Composition, %Carbon 0.50 to 1.00Manganese 0.40 to 1.30Phosphorus, max 0.035Sulfur, max 0.045Silicon 0.15 to 0.60TABLE 2 Grade 4 Extra-High-Strength Tensile RequirementsSpecified Diameter,in.Stressat 1% Extension,min, kpsiUltimateTensile Strength,min, kpsiElongationin 10 in.,min %0.0500
24、to 0.0899, incl 225 265 3.00.0900 to 0.1199, incl 220 260 3.00.1200 to 0.1399, incl 215 255 3.50.1400 to 0.1900, incl 210 250 3.5TABLE 3 Grade 4 Extra-High-Strength Tensile Requirements(Metric)Specified Diameter,mmStressat 1% Extension,min, MPaUltimateTensile Strength,min, MPaElongationin 250 mm,min
25、 %1.27 to 2.28, incl 1550 1825 3.02.29 to 3.04, incl 1515 1790 3.03.05 to 3.55, incl 1480 1760 3.53.56 to 4.82, incl 1450 1725 3.5TABLE 4 Grade 5 Ultra-High-Strength Tensile RequirementsSpecified Diameter,in.Stressat 1% Extension,min, kpsiUltimateTensile Strength,min, kpsiElongationin 10 in.,min %0.
26、0500 to 0.0899, incl 230 285 3.00.0900 to 0.1199, incl 225 275 3.00.1200 to 0.1399, incl 220 270 3.50.1400 to 0.1900, incl 215 265 3.5TABLE 5 Grade 5 Ultra-High-Strength Tensile Requirements(Metric)Specified Diameter,mmStressat 1% Extension,min, MPaUltimateTensile Strength,min, MPaElongationin 250 m
27、m,min %1.27 to 2.28, incl 1580 1965 3.02.29 to 3.04, incl 1550 1900 3.03.05 to 3.55, incl 1515 1860 3.53.56 to 4.82, incl 1480 1825 3.5TABLE 6 Initial Settings for Determining Stress at 1% ExtensionSpecified Diameter,in.Initial Stress,kpsiInitial Settingof Extensometer,in./in.0.0500 to 0.0899, incl
28、18 0.0005 (0.05 % extension)0.0900 to 0.1199, incl 36 0.0010 (0.10 % extension)0.1200 to 0.1900, incl 54 0.0015 (0.15 % extension)B95808211.2 Joints may be made at any stage of processing prior tofinal cold drawing by the electric butt-weld or flash-weldingprocess.11.3 Welding equipment and procedur
29、e shall be such that itcan be demonstrated that the ultimate tensile strength of afinished wire specimen containing the welded section shall benot less than 96 % of the specified minimum stress at 1 %extension.11.4 A welded section shall not be required to meet thestress at 1 % extension, elongation
30、, and wrap tests.12. Density and Resistivity12.1 For the purpose of calculating mass per unit length,cross sections, and so forth, the density of Zn5AlMMalloy-coated steel wire at 20C shall be taken as 0.281lb/in.3(7780 kg/m3).12.2 A maximum resistivity of Zn5AlMM alloy-coatedsteel wire is not guara
31、nteed but a typical value of 0.19157Vmm2/m may be used for calculating purposes. For conversionto other units of conductivity or resistivity, refer to Test MethodB 193.13. Dimensions and Permissible Variations13.1 The specified diameter of the Zn5AlMM alloy-coated wire from Section 4 shall be expres
32、sed in decimalfractions of an inch to four decimal places, or in millimeters totwo decimal places.13.2 To determine the applicable tolerance range from Table12 or Table 13, round the specified diameter to the nearest0.001 in. (0.01 mm) in accordance with the rounding method ofPractice E29.13.3 Measu
33、re the largest and smallest diameter taken at thesame cross section rounded to the nearest 0.001 in. (0.01 mm)in accordance with the rounding method of Practice E29.Calculate the average of the two measurements. The calculatedvalue shall not differ from the specified diameter by more thanthe applica
34、ble tolerance range shown in Table 12 or Table 13.14. Workmanship, Finish, and Appearance14.1 The Zn5AlMM alloy coating shall be reasonablysmooth, continuous, of reasonably uniform thickness and freeof imperfections not consistent with good commercial practice.15. Number of Tests and Retests15.1 One
35、 test specimen shall be taken from each 5000 lb(2500 kg) or fraction thereof in the inspection lot.15.2 Each specimen shall be tested for compliance withSections 7, 8, 10, and 13. At least half of the specimens shallbe tested for compliance with Section 9.TABLE 7 Initial Settings for Determining Str
36、ess at 1% Extension(Metric)Specified Diameter,mmInitial Stress,MPaInitial Settingof Extensometer,mm/mm1.27 to 2.28, incl 125 0.0005 (0.05 % extension)2.29 to 3.04, incl 250 0.0010 (0.10 % extension)3.05 to 4.82, incl 375 0.0015 (0.15 % extension)TABLE 8 Zn-5AlMM Alloy CoatingSpecified Diameterof Coa
37、ted Wire, in.Area Densityof Zn5AlMM Alloy Coatingmin of Uncoated Wire Surface,oz/ft20.0500 to 0.0599, incl 0.600.0600 to 0.0749, incl 0.650.0750 to 0.0899, incl 0.700.0900 to 0.1039, incl 0.750.1040 to 0.1199, incl 0.800.1200 to 0.1399, incl 0.850.1400 to 0.1799, incl 0.900.1800 to 0.1900, incl 1.00
38、TABLE 9 Zn5AlMM Alloy Coating (Metric)Specified Diameterof Coated Wire, mmArea Densityof Zn5AlMM Alloy Coatingmin of Uncoated Wire Surface,g/m21.27 to 1.52, incl 1831.53 to 1.90, incl 1981.91 to 2.28, incl 2142.29 to 2.64, incl 2292.65 to 3.04, incl 2443.05 to 3.55, incl 2593.56 to 4.57, incl 2744.5
39、8 to 4.82, incl 305TABLE 10 Mandrel Size for Adherence TestNOTE 1Loosening or detachment during the adhesion test of super-ficial, small particles of Zn5AlMM alloy formed by mechanicalpolishing of the surface of the coated wire shall not be considered causefor rejection.Specified Wire Diameter,in.Ra
40、tio of Mandrel Diameterto Wire Diameter0.0500 to 0.1399, incl 40.1400 to 0.1900, incl 5TABLE 11 Mandrel Size for Adherence Test (Metric)Specified Wire Diameter,mmRatio of Mandrel Diameterto Wire Diameter1.27 to 3.55, incl 43.56 to 4.82, incl 5TABLE 12 Permissible Variations in Diameter of Zn5AlMMAll
41、oy-Coated Steel WireNOTE 1It is recognized that the surface of coatings, particularly thoseproduced by the hot-dip method of coating, are not perfectly smooth anddevoid of irregularities. If the tolerances shown in the table are rigidlyapplied to such irregularities that are inherent to the product,
42、 unjustifiedrejections of wire that would actually be satisfactory for use could occur.It is intended that these tolerances be used in gaging the wires where thereis a minimum of such diameter irregularities due to hot dip coating.Specified Diameter,in.Permissible Variation,in.Plus Minus0.0500 to 0.
43、0749, incl 0.0015 0.0010.0750 to 0.1199, incl 0.002 0.0020.1200 to 0.1399, incl 0.003 0.0020.1400 to 0.1900, incl 0.004 0.003B95808315.3 Should one or more of the test specimens fail any ofthe tests specified, the nonconforming coil or coils may beremoved and the balance of the lot subjected to rete
44、sts. Forretest purposes, two additional coils for each 5000 lb (2500 kg)in the lot shall be sampled and tested for the property in whichthe original sample failed to comply.15.4 Should any of the retest specimens fail to meet theproperties specified, the lot represented by the test specimensshall be
45、 rejected.15.5 Instead of rejecting the entire lot as provided inParagraph 15.4, the producer may test specimens from everycoil in the lot for the property in which failure occurred andreject only the nonconforming coils.16. Inspection16.1 Unless otherwise specified in the contract or purchaseorder,
46、 the manufacturer shall be responsible for the perfor-mance of all inspection and test requirements specified.16.2 All inspections and tests shall be made at the place ofmanufacture unless otherwise especially agreed to by themanufacturer and the purchaser at the time of the purchase.16.3 The manufa
47、cturer shall afford the inspector represent-ing the purchaser all reasonable manufacturers facilities tosatisfy him that the material is being furnished in accordancewith this specification.17. Rejection and Rehearing17.1 Material that fails to conform to the requirements ofthis specification shall
48、be rejected. Rejection should be re-ported to the producer or supplier promptly and in writing. Incase of dissatisfaction with the results of the test, the produceror supplier may make claim for a rehearing.18. Certification18.1 When specified in the purchase order or contract, aproducers or supplie
49、rs certification shall be furnished to thepurchaser showing that the material was manufactured,sampled, tested, and inspected in accordance with this speci-fication and has been found to meet the requirements. Whenspecified in the purchase order or contract, a report of the testresults shall be furnished.19. Package and Package Marking19.1 The unit lengths shall be as specified in the contract ororder. Length tolerances shall be 6 2 %, unless otherwisespecified by the purchaser. (See Explanatory Note 1.)19.2 Package dimensions
