1、Designation: B 228 04Standard Specification forConcentric-Lay-Stranded Copper-Clad Steel Conductors1This standard is issued under the fixed designation B 228; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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-lay-st
3、randedconductors made from bare round copper-clad steel wires forgeneral use for electrical purposes.1.2 For the purpose of this specification, conductors areclassified as follows: Grade 40 HS, Grade 30 HS, and Grade 30EHS.1.3 The values stated in inch-pound units are to be regardedas the standard.
4、The values given in parentheses are in SI units.2. Referenced Documents2.1 The following documents of the issue in effect on thedate of material purchase form a part of this specification to theextent referenced herein:2.2 ASTM Standards:2B 227 Specification for Hard-Drawn Copper-Clad SteelWireB 354
5、 Terminology Relating to Uninsulated Metallic Elec-trical Conductors2.3 ANSI Standards:C 42 Definitions of Electrical Terms32.4 National Institute of Standards and Technology:NBS Handbook 100Copper Wire Tables43. Ordering Information3.1 Orders for material under this specification shall includethe f
6、ollowing information:3.1.1 Quantity of each size and grade;3.1.2 Conductor size: approximate diameter in fractions ofan inch, or number and AWG size of individual wires (Section7 and Table 1);3.1.3 Grade (see 1.2 and Table 1);3.1.4 Direction of lay of outer layer, if other than left-hand(see 6.3);3.
7、1.5 When physical tests shall be made (see 8.2);3.1.6 Package size (see 13.1);3.1.7 Special package marking, if required (Section 12);3.1.8 Lagging, if required (see 13.2); and3.1.9 Place of inspection (Section 14).3.2 In addition, Supplementary Requirements shall applyonly when specified by the pur
8、chaser in the inquiry, contract, orpurchase order for direct procurement by agencies of the U. S.Government (S1, S2, and S3).4. Material for Wires4.1 The purchaser shall specify the grade of wire to be usedin the conductor.4.2 Before stranding, the copper-clad steel wire shall meetall the requiremen
9、ts of Specification B 227.4.3 All wires in the conductor shall be of the same grade andquality.5. Joints5.1 Joints or splices may be made in the finished individualcopper-clad steel wires composing concentric-lay-strandedconductors, using more than three wires provided that suchjoints or splices hav
10、e a protection equivalent to that of the wireitself and that they do not decrease the strength of the finishedstranded conductor below the minimum breaking strengthshown in Table 1. Such joints or splices shall be not closer than50 ft (15 m) to any other joint in the same layer in theconductor (Note
11、 1).NOTE 1Joints or splices in individual copper-clad steel wires in theirfinished size are made by electrical butt welding. Two types of joints areused and are described as follows:(a) Weld-Annealed JointsAfter butt welding, the wire is annealed fora distance of approximately 5 in. (127 mm) on each
12、 side of the weld. Theweld is then protected from corrosion with a snug fitting seamless coppersleeve which extends at least38 in. (9.5 mm) on each side of the weld andwhich is thoroughly sealed to the wire with solder. The wall thickness of1This specification is under the jurisdiction of ASTM Commi
13、ttee B01 onElectrical Conductors and is the direct responsibility of Subcommittee B01.06 onComposite Conductors.Current edition approved April 1, 2004. Published April 2004. Originallyapproved in 1948. Last previous edition approved in 2002 as B 228 02.2For referenced ASTM standards, visit the ASTM
14、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.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.4
15、Available from National Institute of Standards and Technology (NIST), 100Bureau Dr., Stop 3460, Gaithersburg, MD 20899-3460.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.the sleeve is at least 10 % of the radius of the wire.This jo
16、int has a tensile strength of approximately 60 000 psi (415 MPa).This is less than the strength of the individual wires, but an allowance ismade for this in the rated strength of the conductor as a whole. Thecompleted conductor when containing such joints is required to have thefull rated strength.T
17、his type of joint is but slightly larger than the wire itself and isapplicable for 7, 12, and 19-wire stranded conductors.(b) Compression-Weld JointsCompression-weld joints differ fromweld-annealed joints in that the wire is not annealed after the butt-weldingoperation but is reinforced with a hard-
18、drawn, seamless, silicon-tin bronzesleeve which is applied by means of a hydraulic compressor over the weld.This sleeve is covered with solder so as to completely seal the ends. Thesesleeves have a wall thickness of 25 to 50 % of the radius of the wire,depending on the wire size. Their use is usuall
19、y limited to 3-wireconductors where the relatively large diameter is not objectionable. Thisjoint develops the full strength of the wire.6. Lay6.1 For 3-wire conductors the preferred lay is 1612 times theoutside diameter, but the lay shall not be less than 14 times normore than 20 times this diamete
20、r.6.2 For 7- and 19-wire conductors the preferred lay is 1312times the diameter of that layer, but the lay shall not be lessthan 10 nor more than 16 times this diameter.6.3 The direction of lay of the outer layer shall be left-handunless the direction of lay is specified otherwise by thepurchaser.6.
21、4 The direction of lay shall be reversed in consecutivelayers.6.5 All wires in the conductor shall lie naturally in their truepositions in the completed conductor. They shall tend to remainin position when the conductor is cut at any point and shallpermit restranding by hand after being forcibly unr
22、aveled at theend of the conductor.7. Construction7.1 The numbers and diameters of the wires in theconcentric-lay-stranded conductors shall conform to the re-quirements prescribed in Table 1 (Note 2).NOTE 2For definitions of terms relating to conductors, referenceshould be made to (1) ANSI C42.35-lat
23、est revision and (2) TerminologyB 354.8. Physical and Electrical Tests8.1 Tests for physical and electrical properties of wirescomposing concentric-lay-stranded conductors made fromcopper-clad steel wire shall be made before stranding.TABLE 1 Construction Requirements and Breaking Strength of Concen
24、tric-Lay-Stranded Copper-Clad Steel ConductorsNOTE 1Metric EquivalentsFor diameter, 1 in. = 25.40 mm (round to four significant figures); for breaking strength, 1 lb = 0.45359 kg (round tofour significant figures).Size DesignationConductor Diameter, in.ARated Breaking Strength, min, lbBInchCAWGDGrad
25、e 40 HS Grade 30 HS Grade 30 EHS78 19 No. 5 0.910 50 240 55 570 66 9101316 19 No. 6 0.810 41 600 45 830 55 5302332 19 No. 7 0.721 34 390 37 740 45 8502132 19 No. 8 0.642 28 380 31 040 37 690916 19 No. 9 0.572 23 390 25 500 30 61058 7 No. 4 0.613 22 310 24 780 29 430916 7 No. 5 0.546 18 510 20 470 24
26、 65012 7 No. 6 0.486 15 330 16 890 20 460716 7 No. 7 0.433 12 670 13 910 16 89038 7 No. 8 0.385 10 460 11 440 13 8901132 7 No. 9 0.343 8616 9393 11 280516 7 No. 10 0.306 7121 7758 9 196. . . 3 No. 5 0.392 8373 9262 11 860. . . 3 No. 6 0.349 6934 7639 9754. . . 3 No. 7 0.311 5732 6291 7922. . . 3 No.
27、 8 0.277 4730 5174 6282. . . 3 No. 9 0.247 3898 4250 5129. . . 3 No. 10 0.220 3221 3509 4160. . . 3 No. 12 0.174 1715 . . . . . .ADiameter of circumscribing circle.BBreaking loads of 7-wire and 19-wire conductors are taken as 90 % of the sum of the breaking loads of the individual wires; breaking lo
28、ad of 3-wire conductors is takenas 95 % of the sum of the breaking loads of the individual wires.CThe designation “Inch” is the approximate diameter in proper fraction of an inch.DThe designation of “AWG” is a combination of the number of wires each of the American Wire Gage size indicated by “No.”T
29、ABLE 2 Density of Copper-Clad SteelUnits Grade 40 Density at 20C Grade 30 Density at 20CGrams per cubic centimetre 8.24 8.15Pounds per cubic inch 0.2975 0.2944Pounds per circular mil-foot 0.0000028039 0.0000027750B2280428.2 At the option of the purchaser, tension and elongationtests before stranding
30、 may be waived and the completeconductors may be tested as a unit. The breaking strength of theconductors so tested shall be not less than that required in Table1.8.3 Where breaking strength tests are required on thefinished conductor, they shall be made on representativesamples not less than 4 ft (
31、1.22 m) in length. For lots of 10 000lb (4540 kg) or less, two samples shall be taken from separatereels or coils in the lot except that but one sample shall berequired where the total amount of conductor is 5000 ft (1525m) or less. For quantities over 10 000 lb, one sample for each10 000 lb, or fra
32、ction thereof, shall be taken, but the minimumnumber of samples shall be three.8.4 Specimens of the completed conductor shall be tested ina tensile testing machine equipped with jaws suitable forgripping of the conductor or equipped for holding properlysocketed specimens. Any test in which the resul
33、t is below thestated value and which is obviously caused by impropersocketing of the specimen, or due to the break occurring in orat the gripping jaws of the machine, shall be disregarded andanother sample from the same coil or reel shall be tested.9. Density9.1 For the purpose of calculating mass p
34、er unit length(Note 3), cross sections, and so forth, the density of thecopper-clad steel wire shall be taken as shown in Table 2 (Note4).NOTE 3The term mass per unit length is used in this specification asbeing more technically correct replaces the term “weights.”NOTE 4The value of density of coppe
35、r-clad steel is an average valuewhich has been found to be in accordance with usual values encounteredin practice. Equivalent expressions of density at 20C are given in Table2.10. Mass and Resistance10.1 The mass and electrical resistance of a unit length ofstranded conductor are a function of the l
36、ength of lay. Theapproximate mass and electrical resistance may be determinedusing the standard increments shown in Table 3. When greateraccuracy is desired, the increment based on the specific lay ofthe conductor may be calculated (Note 5).NOTE 5The increment of mass or electrical resistance of a c
37、ompletedconcentric-lay-stranded conductor (k) in percent isk 5 100m 2 1!where m is the stranding factor, and is also the ratio of the mass orelectrical resistance of a unit length of stranded conductor to that of a solidconductor of the same cross-sectional area or of a stranded conductor withinfini
38、te length of stranding, that is, all wires parallel to the conductor axis.The stranding factor m for the completed stranded conductor is thenumerical average of the stranding factors for each of the individual wiresin the conductor, including the straight core wire, if any (for which thestranding fa
39、ctor is unity). The stranding factor (mind) for any given wire ina concentric-lay-stranded conductor ismind5 =1 1 9.8696/n2!where n = length of lay/diameter of helical path of the wire. Thederivation of the above is given in NBS Handbook 100.11. Variation in Area11.1 The area of cross section of the
40、 completed conductorshall be not less than 98 % of the area specified. The area ofcross section of a conductor shall be considered to be the sumof the cross-sectional areas of its component wires at anysection when measured perpendicularly to their individual axes(Note 6).NOTE 6For the convenience o
41、f the users of this specification, Table 4has been prepared giving areas, resistances per 1000 ft, and mass per 1000ft, and per mile, of the various constructions referred to in Table 1.12. Inspection12.1 Unless otherwise specified in the contract or purchaseorder, the manufacturer shall be responsi
42、ble for the perfor-mance of all inspection and test requirements specified.12.2 All inspections and tests shall be made at the place ofmanufacture unless otherwise especially agreed to between themanufacturer and the purchaser at the time of the purchase.12.3 The manufacturer shall afford the inspec
43、tor represent-ing the purchaser all reasonable manufacturers facilities nec-essary to ensure that the material is being furnished inaccordance with this specification.13. Packaging and Package Marking13.1 Package sizes for conductors shall be agreed upon bythe manufacturer and the purchaser in the p
44、lacing of individualorders.13.2 The conductors shall be protected against damage inordinary handling and shipping. If heavy wood lagging isrequired, it shall be specified by the purchaser at the time of thepurchase.13.3 The net mass, length (or lengths, and number oflengths, if more than one length
45、is included in the package),size, grade of conductor, purchase order number, and any othermarks required by the purchase order shall be marked on a tagattached to the end of the conductor inside of the package. Thesame information together with the manufacturers serialnumber (if any) and all shippin
46、g marks required by thepurchaser shall appear on the outside of each package.14. Keywords14.1 clad steel electrical conductor; concentric-lay-strandedcopper-clad steel electrical conductor; copper electricalconductorcopper-clad steel; copper electrical conductorstranded; copper-clad steel electrical
47、 conductor; electricalconductorTABLE 3 Standard Increments Due to StrandingType of ConductorIncrement (Increase) of Resistanceand Mass, %3 Wire 0.87 Wire 1.019 Wire 1.4B228043ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentio
48、nedin 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 responsible technical committee an
49、d 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 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
