1、Designation: A 925 03 (Reapproved 2009)1Standard Specification forZinc-5 % Aluminum-Mischmetal Alloy-Coated SteelOverhead Ground Wire Strand1This standard is issued under the fixed designation A 925; the number immediately following the designation indicates the year oforiginal adoption or, in the c
2、ase 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.1NOTEReapproved with editorial changes in May 2009.1. Scope1.1 This specification covers high-strengt
3、h, extra-high-strength, and utilities grades of concentric lay steel wire strandcomposed of three wires or seven wires with Class A, Class B,or Class C zinc-5 % aluminum-mischmetal (Zn-5 Al-MM)alloy coatings specifically intended for use as overhead groundwires or static wires for electric power tra
4、nsmission lines.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.2. Referenced Documents2.1 ASTM Standards:2A 90/A 90M Test Method for
5、 Weight Mass of Coating onIron and Steel Articles with Zinc or Zinc-Alloy CoatingsA 902 Terminology Relating to Metallic Coated Steel Prod-uctsB 750 Specification for GALFAN (Zinc-5 % Aluminum-Mischmetal) Alloy in Ingot Form for Hot-Dip CoatingsE27 Method for Spectrographic Analysis of Zinc and Zinc
6、Alloys by the Solution-Residue Technique3E47 Test Method for Chemical Analysis of Zinc Die-Casting Alloys32.2 Other Standard:4GF-1 Standard Practice for Determination of Cerium andLanthanum Compositions in Galfan Alloy (5-Al-0.04 %La-0.04 % Ce-Bal SHG Zn)3. Terminology3.1 DefinitionsFor definitions
7、of terms used in this speci-fication refer to Terminology A 902.4. Ordering Information4.1 Orders for strand purchased under this specificationshall include the following information:4.1.1 Quantity of each size,4.1.2 Size and grade of strand (Table 1),4.1.3 Class of Zn-5 Al-MM alloy coating (Section
8、 11 andTable 2), and4.1.4 ASTM designation and year of issue.5. Materials and Manufacture5.1 Base MetalThe base metal shall be steel made by anycommercially accepted steel making process and of suchquality and purity that, when drawn to the size of wire specifiedand coated with Zn-5 Al-MM alloy, the
9、 finished strand and theindividual wires shall be of uniform quality and have theproperties and characteristics as prescribed in this specifica-tion.1This specification is under the jurisdiction of ASTM Committee A05 onMetallic-Coated Iron and Steel Products and is the direct responsibility ofSubcom
10、mittee A05.12 on Wire Specifications.Current edition approved May 1, 2009. Published August 2009. Originallyapproved in 1994. Last previous edition approved in 2003 as A 925 - 03.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org.
11、 For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Available from International Lead Zinc Research Organization, 292 MadisonAve., New York, NY 10017.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West
12、Conshohocken, PA 19428-2959, United States.5.2 Coating Bath AnalysisThe bath metal used in continu-ous hot-dip Zn-5 Al-MM alloy coating shall meet the chemicalcomposition limits specified in Specification B 750.5.2.1 For a two-step coating operation where the firstcoating is zinc (hot-dip galvanized
13、 or electrogalvanized) thefinal bath may have an aluminum content of up to 7.2 %, toprevent depletion of the aluminum content of the bath.5.2.2 Method of AnalysisThe determination of chemicalcomposition shall be made in accordance with suitable chemi-cal (see Test Method E47), spectrochemical (see M
14、ethodE27), or other methods. In case of dispute, the results securedby Test Method E47shall be the basis of acceptance.5.2.3 A standard practice of X-ray fluorescence spectrom-etry for determination of cerium and lanthanum in a Zn-5Al-MM alloy has been established by the International LeadZinc Resea
15、rch Organization (Standard Practice GF-1).6. Stranding6.1 The strand shall have a left lay with a uniform pitch ofnot more than 16 times the nominal diameter of the strand. Aleft lay is defined as a counter-clockwise twist away from theobserver. Stranding shall be sufficiently close to ensure nosign
16、ificant reduction in diameter when stressed to 10 % of theminimum breaking strength.7. Preforming Strand7.1 Preformed strand shall be supplied when so specified bythe purchaser. Strand is preformed when the component wiresare set to the helical form which they assume in the product byany means of pr
17、ocess other than by merely laying them aboutthe strand core.8. Breaking Strength and Weight8.1 The approximate weight per unit length of strand andthe minimum breaking strength of the finished strand shall beas specified in Table 1.8.2 A test in which the breaking strength is below theminimum specif
18、ied and which may have been caused by theslipping of the specimen in the jaws of the testing machine, bybreaking within the jaws, or within 1 in. (25.4 mm) of the jaws,or by the improper socketing of a specimen shall be disre-garded and another sample from the same coil or reel shall betested.9. Elo
19、ngation9.1 The elongation of the strand in 24 in. (610 mm),determined in accordance with 9.2, shall be not less than 5 %for the high-strength and for the516-in. (7.94-mm), three-wireutilities grades, and 4 % for the extra-highstrength and for the38-in. (9.52-mm), seven-wire utilities grades.9.2 The
20、elongation shall be measured as the percentageincrease in separation between the jaws of the testing machinefrom the position after application of the initial load, to theposition at initial failure in the test specimen. The separation ofthe jaws of the testing machine shall be approximately 2 ft(0.
21、61 m) when under an initial load equal to 10 % of therequired minimum breaking strength of the strand. The elon-gation values shall be recorded only for specimens that breakover 1 in. (25.4 mm) from jaws of the testing machine.10. Ductility of Steel10.1 The individual wires of the completed strand s
22、hall notfracture when wrapped at a rate not exceeding 15 turns perminute in a close helix of at least two turns around a cylindricalmandrel equal to three times the nominal diameter of the wireunder test.11. Weight of Coating11.1 The weight of Zn-5 Al-MM alloy coating shall not beless than that spec
23、ified in Table 2.11.2 Weight of Coating TestThe Zn-5 Al-MM alloy coat-ing shall be tested for weight by a stripping test in accordancewith Test Method A 90/A 90M.12. Adherence of Coating12.1 The Zn-5Al-MM alloy coating shall adhere to the wirewithout delaminating and without being removable by rubbi
24、ngwith the bare fingers after the individual wires have beenwrapped at a rate not exceeding 15 turns per minute, in a closehelix of at least two turns around a cylindrical mandrel equal tothree times the nominal diameter of the wire under test.Loosening or detachment during the adhesion tests of sup
25、erfi-cial, small particles of Zn-5 Al-MM alloy formed by mechani-cal polishing of the surface of Zn-5 Al-MM alloy-coated wireshall not be considered cause for rejection.13. Joints and Splices13.1 There shall be no joints of any kind made in thefinished wire entering into the construction of the stra
26、nd.TABLE 1 Physical Properties of Zn-5 Al-MM Alloy-Coated Steel Overhead Ground Wire StrandNominal Diameter ofStrand, in. (mm)Number of Wires inStrandNominal Diameter ofCoated Wire in Strand,in. (mm)Approximate Weight ofStrand, lb/1000 ft (kg/km)Minimum Breaking Strength of Strand, lbf (kN)High-Stre
27、ngth GradeExtra-High-StrengthGradeUtilities Grade516 (7.94) 3 0.145 (3.68) 171 (255) . . . . . . 6500 (28.9)516 (7.94) 7 0.104 (2.64) 205 (305) 8000 (35.6) 11 200 (49.8) . . .38 (9.52) 7 0.120 (3.05) 273 (407) 10 800 (48.0) 15 400 (68.4) 11 500 (51.2)716 (11.11) 7 0.145 (3.68) 399 (595) 14 500 (64.5
28、) 20 800 (92.5) . . .12 (12.7) 7 0.165 (4.19) 517 (770) 18 800 (83.6) 26 900 (119.6) . . .TABLE 2 Minimum Weights of CoatingNominal Diameterof Coated Wire,in. (mm)Minimum Weight of Coating of UncoatedWire Surface, oz/ft2(g/m2)Class A Class B Class C0.104 (2.64) 0.80 (245) 1.60 (490) 2.40 (730)0.120
29、(3.05) 0.85 (260) 1.70 (520) 2.55 (780)0.145 (3.68) 0.90 (275) 1.80 (550) 2.70 (825)0.165 (4.19) 0.90 (275) 1.80 (550) 2.70 (825)A 925 03 (2009)1213.2 Electric-welded butt joints made prior to the start ofcold drawing of the wire are permitted; however, no electric-welded butt joints of the wire sha
30、ll be made during the colddrawing application.13.3 There shall be no strand joints or strand splices in anylength of the completed strand.14. Permissible Variations in Wire Size14.1 The diameter of the Zn-5 Al-MM alloy-coated wireforming the strand shall conform to the nominal diametershown in Table
31、 2 within a tolerance of 60.004 in. (0.102 mm)for wire sizes 0.104 in. (2.642 mm) and 0.120 in. (3.048 mm)and 60.005 in. (0.127 mm) for wire sizes 0.145 in. (3.683 mm)and 0.165 in. (4.191 mm).15. Workmanship, Finish, and Appearance15.1 The Zn-5Al-MM alloy-coated wire shall be uniform indiameter and
32、shall be free from splints, scales, inequalities,flaws, and other imperfections not consistent with good com-mercial practice. The coating shall be continuous and reason-ably uniform.16. Sampling16.1 The number of samples to be taken shall be determinedby lot size as follows:Lot Size Number of Sampl
33、es1 to 3 reels 1 from each reel4to30reels 3min31 reels or greater 4 min16.2 Each sample taken shall be subjected to all testsprescribed in Sections 6, 8, and 9.16.3 In addition to the strand testing in 16.2, the individualwires from the strand samples shall be tested for compliancewith Sections 10,
34、11, 12, and 14. Select all three wires inthree-wire strand, and four of the wires in seven-wire strand.Individual wire samples selected for compliance to Section 14shall be discarded if any distortion of the wire occurred duringthe stranding operation.16.4 Instead of testing the wires from the compl
35、eted strandin accordance with 16.3, the producer may elect to establishcompliance with Sections 10, 11, 12, and 14 of this specifica-tion by tests made on the wires prior to stranding, unlessotherwise stipulated by the purchaser. However, if the producermakes this election, the purchaser shall still
36、 reserve the right totest wires from the completed strand for compliance.17. Inspection17.1 The manufacturer shall afford the inspector represent-ing the purchaser all reasonable facilities to satisfy him that thematerial is being furnished in accordance with this specifica-tion. All tests and inspe
37、ction shall be made on the finishedstrand at the place of manufacture prior to shipment and shallbe so conducted as not to interfere unnecessarily with theoperation of the works.18. Rejection18.1 In case there is a reasonable doubt in the first trial as tothe failure of the wire or strand to meet an
38、y requirement of thisspecification, two additional tests shall be made on samples ofwire or strand from the same coil or reel, and if failure occursin either of these tests, the strand shall be rejected.19. Packaging and Package Marking19.1 The completed strand shall be furnished on reelssufficientl
39、y sturdy to withstand normal service incident toshipping, hauling, and field erection.19.2 The completed strand shall be furnished in randomlengths. At least 95 % of the lengths shall be within theminimum and maximum limits shown in Table 3. Not morethan 5 % of a total length ordered may be furnishe
40、d in lengthsthat are below the minimum limits shown in Table 3 but whichare not less than 1500 ft (457 m) long. Each reel shall beclearly marked to show the length of the strand containedthereon.19.3 Each reel shall have a strong tag securely fastened to itshowing the name of the material “ground wi
41、re strand,” thelength, size, grade of the strand, class of coating, ASTMspecification number (A 925), and the name or mark of themanufacturer.20. Keywords20.1 coated overhead strand; zinc 5 % aluminum-mischmetal alloy-coated overhead strandTABLE 3 Range of Strand Lengths per Reel for at Least 95 % o
42、fthe Completed StrandNominal Diameterof Strand, in. (mm)Number of Wires inStrandLength of Strand Per Reel for at Least95 % of the Order, ft (m)Min Max516 (7.94) 3 4700 (1430) 7900 (2410)516 (7.94) 7 4800 (1460) 7700 (2350)A38 (9.52) 7 3600 (1100) 5800 (1770)A716 (11.11) 7 4700 (1430) 7900 (2410)12 (
43、12.7) 7 3600 (1100) 6100 (1860)APurchasers may procure maximum lengths up to 12 000 ft (3660 m) for516-in.(7.94-mm) diameter strand and up to 9400 ft (2860 m) for38-in. (9.52-mm)diameter strand.A 925 03 (2009)13ASTM International takes no position respecting the validity of any patent rights asserte
44、d in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by th
45、e responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive
46、careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM Internat
47、ional, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).A 925 03 (2009)14
