1、Designation: A 925 03Standard 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 case of revision, th
2、e year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers high-strength, extra-high-strength, and utilities grades of concentric lay steel
3、 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 transmission lines.1.2 The values stated in inch-pound units are to be
4、regardedas the standard. The values given in brackets are for informa-tion only.2. Referenced Documents2.1 ASTM Standards:2A 90/A 90M Test Method for Weight Mass of Coating onIron and Steel Articles with Zinc or Zinc-Alloy CoatingsA 902 Terminology Relating to Metallic-Coated Steel Prod-uctsB 750 Sp
5、ecification for Zinc-5 % Aluminum-MischmetalAlloy (UNS Z 38510) in Ingot Form for Hot-Dip CoatingsE27 Method for Spectrographic Analysis of Zinc and ZincAlloys by the Solution-Residue TechniqueE47 Test Method for Chemical Analysis of Zinc Die-Casting Alloys2.2 Other Standard:3GF-1 Standard Practice
6、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 of terms used in this speci-fication refer to Terminology A 902.4. Ordering Information4.1 Orders for strand purchased under this specificationshall
7、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 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 anycomme
8、rcially 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 finished strand and theindividual wires shall be of uniform quality and have theproperties and characteristics as prescribed in this specifica-tion.
9、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 or electrogalvanized) thefinal bath may ha
10、ve 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 MethodE27), or other methods. In case of dis
11、pute, 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 Research Organization (Standard Practice GF-1).6
12、. 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 nosignificant reduction in diameter when stressed
13、 to 10 % of theminimum breaking strength.1This specification is under the jurisdiction of ASTM Committee A05 onMetallic-Coated Iron and Steel Products and is the direct responsibility ofSubcommittee A05.12 on Wire Specifications.Current edition approved Oct. 1, 2003. Published December 2003. Origina
14、llyapproved in 1994. Last previous edition approved in 1998 as A 925 - 98.2For 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
15、ASTM website.3Available from International Lead Zinc Research Organization, 292 MadisonAve., New York, NY 10017.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Pref
16、orming 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 process other than by merely laying them aboutthe strand core.8. Breaking Strength and Weight
17、8.1 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 specified and which may have been caused by theslipping of the specimen in the jaws of the testin
18、g 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. Elongation9.1 The elongation of the strand in 24 in. 610 mm,determined in accordance with 9.2, s
19、hall 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 elongation shall be measured as the percentageincrease in separation between the jaws of the testin
20、g 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 ft0.61 m when under an initial load equal to 10 % of therequired minimum breaking strength of the strand
21、. 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 shall notfracture when wrapped at a rate not exceeding 15 turns perminute in a close helix of at least t
22、wo 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 specified in Table 2.11.2 Weight of Coating TestThe Zn-5 Al-MM alloy coat-ing shall be tested for weight by
23、 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 rubbingwith the bare fingers after the individual wires have beenwrapped at a rate not exceeding 15 turns pe
24、r 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 superfi-cial, small particles of Zn-5 Al-MM alloy formed by mechani-cal polishing of the surface of Zn-5 A
25、l-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 strand.13.2 Electric-welded butt joints made prior to the start ofcold drawing of the wire are permitted; h
26、owever, no electric-welded butt joints of the wire shall 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 stra
27、nd shall conform to the nominal diametershown in Table 2 within a tolerance of 60.004 in. 0.102 mmfor wire sizes 0.104 in. 2.642 mm and 0.120 in. 3.048 mmand 60.005 in. 0.127 mm for wire sizes 0.145 in. 3.683 mmand 0.165 in. 4.191 mm.15. Workmanship, Finish, and Appearance15.1 The Zn-5Al-MM alloy-co
28、ated wire shall be uniform indiameter and 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.TABLE 1 Physical Properties of Zn-5 Al-MM Alloy-Coated Steel Overhead Groun
29、d Wire StrandNominal Diameter ofStrand, in. mmNumber of Wires inStrandNominal Diameter ofCoated Wire in Strand,in. mmApproximate Weight ofStrand, lb/1000 ftkg/kmMinimum Breaking Strength of Strand, lbf kNHigh-Strength GradeExtra-High-StrengthGradeUtilities Grade516 7.94 3 0.145 3.68 171 255 . . . .
30、. . 6500 28.9516 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 51.2716 11.11 7 0.145 3.68 399 595 14 500 64.5 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 Diame
31、terof Coated Wire,in. mmMinimum Weight of Coating of UncoatedWire Surface, oz/ft2g/m2Class A Class B Class C0.104 2.64 0.80 245 1.60 490 2.40 7300.120 3.05 0.85 260 1.70 520 2.55 7800.145 3.68 0.90 275 1.80 550 2.70 8250.165 4.19 0.90 275 1.80 550 2.70 825A92503216. Sampling16.1 The number of sample
32、s to be taken shall be determinedby lot size as follows:Lot Size Number of Samples1 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 individu
33、alwires from the strand samples shall be tested for compliancewith Sections 10, 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 occurre
34、d duringthe stranding operation.16.4 Instead of testing the wires from the completed 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 p
35、urchaser. However, if the producermakes this election, the purchaser shall still 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 themateria
36、l is being furnished in accordance with this specifica-tion. All tests and inspection 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 reaso
37、nable doubt in the first trial as tothe failure of the wire or strand to meet any 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
38、 Package Marking19.1 The completed strand shall be furnished on reelssufficiently 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 lim
39、its shown in Table 3. Not morethan 5 % of a total length ordered may be furnished 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
40、 strong tag securely fastened to itshowing the name of the material “ground wire 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-coat
41、ed overhead strandSUMMARY OF CHANGESCommitteeA05 has identified the location of selected changes to this standard since the last issue (A 925 - 98)that may impact the use of this standard.A 925 - 03:(1) Renumbered sections to meet Form and Style requirements.(2) Deleted “Size of Strand” section(3) C
42、hanged “base metal” in 5.1 to “any commercially ac-cepted steel making process.”(4) Rewrote Section 8. (Breaking Strength and Weight)(5) Made editorial changes in paragraphs 11.1-11.2, 12.1, andSections 13 and 18.(6) Changed kg/m to kg/km in Table 1.(7) Added Summary of Changes section.TABLE 3 Range
43、 of Strand Lengths per Reel for at Least 95 % ofthe Completed StrandNominal Diameterof Strand, in. mmNumber of Wires inStrandLength of Strand Per Reel for at Least95 % of the Order, ft mMin Max516 7.94 3 4700 1430 7900 2410516 7.94 7 4800 1460 7700 2350A38 9.52 7 3600 1100 5800 1770A716 11.11 7 4700
44、 1430 7900 241012 12.7 7 3600 1100 6100 1860APurchasers 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 diameterstrand.A925033ASTM International takes no position respecting the validity of any patent rights asserted in
45、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 the res
46、ponsible 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 caref
47、ul 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 International
48、, 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).A925034
