ASTM B778-02(2012)
(Specification)Standard Specification for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors (AAC/TW)
Standard Specification for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors (AAC/TW)
ABSTRACT
This specification covers shaped wire compact concentric-lay-stranded aluminum conductor (AAC/TW) and its component wires for use as overhead electrical conductors. The trapezoidal aluminum wires shall meet the prescribed tensile strength and elongation requirements. Electric-butt welds, electric-butt cold-upset welds, or cold-pressure welds may be made in the individual aluminum wires during the stranding process. Requirements for the lay and construction of the conductor are detailed. The methods of determining the rated strength, breaking strength, mass, and electrical resistance are given. Tests for mechanical and electrical properties of aluminum wires shall be made before stranding. For the purpose of calculating mass per unit length, cross-sections, and the like, the density of aluminum to be taken is specified.
SCOPE
1.1 This specification covers shaped wire compact concentric-lay-stranded aluminum conductor (AAC/TW) and its component wires for use as overhead electrical conductors (Explanatory Note 1 and Note 2).
1.2 The values stated in inch-pound units are to be regarded as the standard with the exception of temperature and resistivity. The SI equivalents of inch-pound units may be approximate. Note 1—AAC/TW is designed to increase the aluminum area for a given diameter of conductor by the use of trapezoidally shaped wires (TW). The conductors consist of a central core of one round aluminum wire or a seven-strand compact round core surrounded by two or more layers of trapezoidal aluminum 1350-H19 wires. For the purposes of this specification, the sizes listed are tabulated on the basis of the finished conductor having an area equal to that of specific sizes of standard AAC (Table 1) or in fixed diameter increments (Table 2) so as to facilitate conductor selection.TABLE 1 Construction Requirements for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors Sized to Have Areas Equal to AAC Size
Code WordA
AAC/TW
Conductor size
Nominal Outside
Diameter
Number of
Aluminum
Wires
Number
of Layers
Nominal Mass
Rated Strength
kcmil
mm
in.
mm
lb/1000ft
kg/km
1000 lbf
kN
Tulip/TW
336.4
170
0.612
15.5
17
2
315.3
469.4
6.02
26.8
Canna/TW
397.5
201
0.661
16.8
17
2
372.6
554.7
6.96
31
Cosmos/TW
477.0
242
0.720
18.3
17
2
447.1
665.6
8.36
37.2
Zinnia/TW
500.0
253
0.736
18.7
17
2
468.7
697.7
8.76
39
Mistletoe/TW
556.5
282
0.775
19.7
17
2
521.6
776.5
9.75
43.4
Meadowsweet/TW
600.0
304
0.803
20.4
17
2
562.4
837.2
10.52
46.8
Orchid/TW
636.0
322
0.825
21.0
17
2
596.1
887.4
11.1
49.4
Verbena/TW
700.0
355
0.864
21.9
17
2
656.1
976.7
12.3
54.7
Nasturtium/TW
750.0
380
0.893
22.7
17
2
702.1
1045
13.1
58.3
Arbutus/TW
795.0
403
0.919
23.3
17
2
745.1
1109
13.6
60.5
Cockscomb/TW
900.0
456
0.990
25.1
31
3
843.6
1256
15.4
68.5
Magnolia/TW
954.0
483
1.018
25.9
31
3
894.2
1331
16.4
72.9
Hawkweed/TW
1000.0
507
1.041
26.4
31
3
937.3
1395
17.1
76.1
Bluebell/TW
1033.5
524
1.057
26.8
31
3
968.7
1442
17.7
78.7
Marigold/TW
1113.0
564
1.095
27.8
31
3
1043.2
1553
19.1
85.0
Hawthorn/TW
1192.5
604
1.132
28.8
31
3
1117.7
1664
20.4
90.7
Narcissus/TW
1272.0
644
1.168
29.7
31
3
1192.2
1775
21.8
97.0
Columbine/TW
1351.5
685
1.202
30.5
31
3
1266.3
1885
23.2
103
Carnation/TW
1431.0
725
1.236
31.4
31
3
1341.3
1997
24.0
107
Coreopsis/T...
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:B778 −02(Reapproved 2012)
Standard Specification for
Shaped Wire Compact Concentric-Lay-Stranded Aluminum
Conductors (AAC/TW)
This standard is issued under the fixed designation B778; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E29 Practice for Using Significant Digits in Test Data to
Determine Conformance with Specifications
1.1 This specification covers shaped wire compact
E527 Practice for Numbering Metals and Alloys in the
concentric-lay-stranded aluminum conductor (AAC/TW) and
Unified Numbering System (UNS)
its component wires for use as overhead electrical conductors
2.3 Other Documents:
(Explanatory Note 1 and Note 2).
ANSI H35.1 American National StandardAlloy and Temper
1.2 The values stated in inch-pound units are to be regarded 3
Designation Systems for Aluminum
as the standard with the exception of temperature and resistiv- 4
NBS Handbook 100 Copper Wire Tables
ity. The SI equivalents of inch-pound units may be approxi-
Aluminum Association Publication 50 Code Words for
mate. 5
Overhead Aluminum Electrical Conductors
NOTE 1—AAC/TW is designed to increase the aluminum area for a
3. Ordering Information
given diameter of conductor by the use of trapezoidally shaped wires
(TW). The conductors consist of a central core of one round aluminum
3.1 Orders for material under this specification shall include
wire or a seven-strand compact round core surrounded by two or more
the following information:
layers of trapezoidal aluminum 1350-H19 wires. For the purposes of this
3.1.1 Quantity of each size,
specification, the sizes listed are tabulated on the basis of the finished
conductor having an area equal to that of specific sizes of standard AAC
3.1.2 Conductor size: kcmil area and diameter (Table 1 and
(Table 1) or in fixed diameter increments (Table 2) so as to facilitate
Table 2),
conductor selection.
3.1.3 Special tension test, if required (see 8.2),
NOTE 2—The aluminum and temper designations conform to ANSI
3.1.4 Place of inspection (Section 15),
Standard H 35.1. Aluminum 1350 corresponds to Unified Numbering
3.1.5 Package size and type (see 15.1),
System (UNS) A91350 in accordance with Practice E527.
3.1.6 Special package markings, if required (Section 15),
2. Referenced Documents
and
3.1.7 Heavy wood lagging, if required (see 15.3).
2.1 The following documents of the issue in effect on date
of material purchase form a part of this specification to the
4. Requirement for Wires
extent referenced herein.
4.1 Before stranding, the trapezoidal aluminum wires shall
2.2 ASTM Standards:
conform to the requirements of Specification B230/B230M
B230/B230M Specification for Aluminum 1350–H19 Wire
except for shape and diameter tolerance. The tensile strength
for Electrical Purposes
and elongation requirements of trapezoidal wires shall be the
B263 Test Method for Determination of Cross-Sectional
sameasforroundwiresofequalarea.Theareatolerancesshall
Area of Stranded Conductors
be such that the finished conductor conforms to Section 11.
B354 Terminology Relating to Uninsulated Metallic Electri-
cal Conductors
5. Joints
5.1 Electric-butt welds, electric-butt cold-upset welds, or
cold-pressure welds may be made in the individual aluminum
This specification is under the jurisdiction of ASTM Committee B01 on
wires during the stranding process. No weld shall occur within
Electrical Conductors and is the direct responsibility of Subcommittee B01.07 on
Conductors of Light Metals.
Current edition approved Oct. 15, 2012. Published November 2012. Originally
approved in 1987. Last previous edition approved in 2007 as B778 – 02 (2007). Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
DOI: 10.1520/B0778-02R12. 4th Floor, New York, NY 10036, http://www.ansi.org.
2 4
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from National Institute of Standards and Technology (NIST), 100
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http://www.nist.gov.
Standards volume information, refer to the standard’s Document Summary page on Available from Aluminum Association, Inc., 1525 Wilson Blvd., Suite 600,
the ASTM website. Arlington, VA 22209, http://www.aluminum.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B778−02 (2012)
TABLE 1 Construction Requirements for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors Sized to Have Areas
Equal to AAC Size
AAC/TW Nominal Outside
Number of
Nominal Mass Rated Strength
Number
A
Conductor size Diameter
Code Word Aluminum
of Layers
Wires
kcmil mm in. mm lb/1000ft kg/km 1000 lbf kN
Tulip/TW 336.4 170 0.612 15.5 17 2 315.3 469.4 6.02 26.8
Canna/TW 397.5 201 0.661 16.8 17 2 372.6 554.7 6.96 31
Cosmos/TW 477.0 242 0.720 18.3 17 2 447.1 665.6 8.36 37.2
Zinnia/TW 500.0 253 0.736 18.7 17 2 468.7 697.7 8.76 39
Mistletoe/TW 556.5 282 0.775 19.7 17 2 521.6 776.5 9.75 43.4
Meadowsweet/TW 600.0 304 0.803 20.4 17 2 562.4 837.2 10.52 46.8
Orchid/TW 636.0 322 0.825 21.0 17 2 596.1 887.4 11.1 49.4
Verbena/TW 700.0 355 0.864 21.9 17 2 656.1 976.7 12.3 54.7
Nasturtium/TW 750.0 380 0.893 22.7 17 2 702.1 1045 13.1 58.3
Arbutus/TW 795.0 403 0.919 23.3 17 2 745.1 1109 13.6 60.5
Cockscomb/TW 900.0 456 0.990 25.1 31 3 843.6 1256 15.4 68.5
Magnolia/TW 954.0 483 1.018 25.9 31 3 894.2 1331 16.4 72.9
Hawkweed/TW 1000.0 507 1.041 26.4 31 3 937.3 1395 17.1 76.1
Bluebell/TW 1033.5 524 1.057 26.8 31 3 968.7 1442 17.7 78.7
Marigold/TW 1113.0 564 1.095 27.8 31 3 1043.2 1553 19.1 85.0
Hawthorn/TW 1192.5 604 1.132 28.8 31 3 1117.7 1664 20.4 90.7
Narcissus/TW 1272.0 644 1.168 29.7 31 3 1192.2 1775 21.8 97.0
Columbine/TW 1351.5 685 1.202 30.5 31 3 1266.3 1885 23.2 103
Carnation/TW 1431.0 725 1.236 31.4 31 3 1341.3 1997 24.0 107
Coreopsis/TW 1590.0 805 1.315 33.4 49 4 1490.3 2219 27.0 120
Jessamine/TW 1750.0 887 1.377 35.0 49 4 1640.3 2442 29.7 132
Cowslip/TW 2000.0 1013 1.468 37.3 49 4 1893.0 2818 33.9 151
Lupine/TW 2500.0 1266 1.648 41.9 71 5 2366.2 3522 41.9 186
Trillium/TW 3000.0 1520 1.799 45.7 71 5 2839.5 4227 50.3 224
A
Code words shown in this column are obtained from “Publication 50, Code Words for OverheadAluminum Electrical Conductors,” by theAluminumAssociation. They
are provided for information only.
TABLE 2 Construction Requirements for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors, in
Fixed-Diameter Increments
AAC/TW Nominal Outside
Number of
Nominal Mass Rated Strength
Number
A
Conductor Size Diameter
Code Word Aluminum
of Layers
Wires
kcmil mm in. mm lb/1000 ft kg/km 1000 lbf kN
Logan/TW 322.5 163 0.60 15.2 17 2 302.3 450 5.88 26.2
384.5 195 0.65 16.5 17 2 360.4 536.5 6.74 30
Wheeler/TW 449.4 228 0.70 17.8 17 2 421.2 627 7.88 35.1
521.7 264 0.75 19.1 17 2 489.0 728 9.14 40.7
Robson/TW 595.8 302 0.80 20.3 17 2 558.4 831.3 10.44 46.4
678.2 344 0.85 21.6 17 2 635.7 946.3 11.88 52.8
McKinley/TW 761.5 386 0.90 22.9 17 2 713.7 1062.5 13.07 58.1
854.2 433 0.95 24.1 17 2 800.6 1191.8 14.86 66.1
Rainer/TW 918.8 465 1.00 25.4 31 3 861.2 1282 15.76 70.1
1020.0 517 1.05 26.7 31 3 956.0 1423.2 17.50 77.8
Helens/TW 1123.1 569 1.10 27.9 31 3 1052.7 1567.1 19.26 85.7
1234.2 625 1.15 29.2 31 3 1156.8 1722.1 21.17 94.2
Mazama/TW 1346.8 682 1.20 30.5 31 3 1262.3 1879.1 23.10 102.7
1467.9 744 1.25 31.8 31 3 1375.9 2048.2 24.65 109.6
Hood/TW 1583.2 802 1.30 33 34 3 1483.9 2209 26.59 118.3
1682.7 852 1.35 34.3 49 4 1577.5 2348.4 28.55 127
Whitney/TW 1812.7 918 1.40 35.6 49 4 1699.0 2529.2 30.74 136.7
1954.3 990 1.45 36.8 49 4 1832.1 2727.4 33.16 147.5
Powell/TW 2093.6 1061 1.50 38.1 49 4 1981.6 2949.9 35.51 157.9
2245.4 1137 1.55 39.4 49 4 2125.7 3164.4 37.30 165.9
Jefferson/ 2388.1 1210 1.60 40.6 52 4 2260.3 3364.8 39.67 176.5
TW
2514.8 1274 1.65 41.9 71 5 2379.5 3542.3 42.17 187.6
Shasta/TW 2667.2 1351 1.70 43.2 71 5 2524.5 3758.1 44.74 199
2844.5 1441 1.75 44.5 71 5 2692.2 4007.8 47.70 212.2
Adams/TW 3006.2 1523 1.80 45.7 71 5 2873.0 4276.9 50.43 224.3
A
Code words shown in this column are obtained from “Publication 50, Code Words for OverheadAluminum Electrical Conductors,” by theAluminumAssociation. They
are provided for information only.
50 ft (15 m) of any other weld in the completed conductor
(Explanatory Note 3).
B778−02 (2012)
6. Lay failure occurs in the free length at least 1 in. (25 mm) beyond
the end of either gripping device, or shall be not less than 95 %
6.1 Thepreferredlayoftheoutsidelayerofaluminumwires
of the rated strength if failure occurs inside or within 1 in. of
ofshapedwirealuminumconductors,havingmultiplelayersof
the end of either gripping device (Explanatory Note 2).
aluminum wires is 11 times the outside diameter of the
conductorbutthelayshallnotbelessthan10normorethan14 8.3 Rated strength and breaking strength values shall be
times that diameter (Explanatory Note 1). rounded to three significant figures in the final value only, in
accordance with Practice E29.
6.2 The preferred lay of the layer immediately beneath the
outside layer of aluminum wires is 13 times the outside
9. Density
diameter of such layer but the lay shall be not less than 10 nor
9.1 For the purpose of calculating mass per unit length,
more than 16 times that diameter.
cross-sections,andthelike,thedensityofaluminum1350shall
3 3
6.3 The lay of the inner layers of aluminum wires shall be
be taken as 0.0975 lb/in. (2705 kg/m ) at 20°C.
not less than 10 nor more than
...
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