ASTM B779-96

Standard Specification for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors, Steel-Reinforced (ACSR/TW)

SCOPE
1.1 This specification covers shaped wire compact concentric-lay-stranded aluminum conductor, steel-reinforced (ACSR/TW) and its component wires for use as overhead electrical conductors (Explanatory Notes 1 and 2).  
1.2 The values stated in inch-pound units are to be regarded as the standard with the exception of temperature, density, and resistivity. The SI equivalents of inch-pound units may be approximate.  Note 1-ACSR/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 round steel wire(s) surrounded by two or more layers of trapezoidal aluminum 1350-H19 wires. Different strandings of the same size of conductor are identified by type, which is the approximate ratio of steel area to aluminum area expressed in percent (Tables 1, 2 and 3). For the purpose of this specification, the sizes listed in Tables 1 and 2 are tabulated on the basis of the finished conductor having an area or outside diameter equal to that of specific sizes of standard ACSR so as to facilitate conductor selection. Note 2-The aluminum and temper designations conform to ANSI Standard H35.1. Aluminum 1350 corresponds to Unified Numbering System (UNS) A91350 in accordance with Practice E527.

General Information

• Status: Historical
• Publication Date: 31-Dec-1995
• ICS: 29.240.20 - Power transmission and distribution lines
• Technical Committee: B01 - Electrical Conductors
• Drafting Committee: B01.07 - Conductors of Light Metals

Relations

• Replaced By: ASTM B779-03 - Standard Specification for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors, Steel-Reinforced (ACSR/TW)
• Effective Date: 10-Apr-2003
• Referred By: ASTM B1006-17 - Standard Specification for Electrical Overhead Conductor Code Word Names
• Effective Date: 01-Jan-1996

Standards Content (Sample)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: B 779 – 96
Standard Specification for
Shaped Wire Compact Concentric-Lay-Stranded Aluminum
Conductors, Steel-Reinforced (ACSR/TW)
This standard is issued under the fixed designation B 779; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope Core Wire for Aluminum Conductors, Steel Reinforced
(ACSR)
1.1 This specification covers shaped wire compact
B 500 Specification for Metallic Coated Stranded Steel
concentric-lay-stranded aluminum conductor, steel-reinforced
Core for Aluminum Conductors, Steel Reinforced
(ACSR/TW) and its component wires for use as overhead
(ACSR)
electrical conductors (Explanatory Note 1 and Note 2).
B 502 Specification for Aluminum-Clad Steel Core Wire for
1.2 The values stated in inch-pound units are to be regarded
Aluminum Conductors, Aluminum-Clad Steel Reinforced
as the standard with the exception of temperature, density, and
B 549 Specification for Concentric-Lay-Stranded Alumi-
resistivity. The SI equivalents of inch-pound units may be
num Conductors, Aluminum-Clad Steel Reinforced
approximate.
(ACSR/AW)
NOTE 1—ACSR/TW is designed to increase the aluminum area for a
B 606 Specification for High-Strength Zinc-Coated (Galva-
given diameter of conductor by the use of trapezoidally shaped wires
nized) Steel Core Wire for Aluminum and Aluminum Alloy
(TW). The conductors consist of a central core of round steel wire(s)
Conductors, Steel Reinforced
surrounded by two or more layers of trapezoidal aluminum 1350-H19
B 802 Specification for Zinc-5 % Aluminum-Mischmetal
wires. Different strandings of the same size of conductor are identified by
type, which is the approximate ratio of steel area to aluminum area Alloy-Coated Steel Core Wire for Aluminum Conductors,
expressed in percent (Table 1, Table 2 and Table 3). For the purpose of this
Steel Reinforced (ACSR)
specification, the sizes listed in Table 1 and Table 2 are tabulated on the
B 803 Specification for High-Strength Zinc-5 %
basis of the finished conductor having an area or outside diameter equal to
Aluminum-Mischmetal Alloy-Coated Steel Core Wire for
that of specific sizes of standard ACSR so as to facilitate conductor
Aluminum and Aluminum-Alloy Conductors, Steel Rein-
selection.
forced
NOTE 2—The aluminum and temper designations conform to ANSI
E 29 Practice for Using Significant Digits in Test Data to
Standard H 35.1. Aluminum 1350 corresponds to Unified Numbering
System (UNS) A91350 in accordance with Practice E 527. Determine Conformance with Specifications
E 527 Practice for Numbering Metals and Alloys (UNS)
2. Referenced Documents
2.2 Other Documents:
2.1 ASTM Standards:
ANSI H35.1 American National Standard Alloy and Tem-
B 230 Specification for Aluminum 1350-H19 Wire for Elec-
per Designation Systems for Aluminum
trical Purposes NBS Handbook 100—Copper Wire Tables of the National
B 232 Specification for Concentric-Lay-Stranded Alumi-
Bureau of Standards
num Conductors, Coated Steel-Reinforced (ACSR)
3. Terminology
B 263 Test Method for Determination of Cross-Sectional
Area of Stranded Conductors
3.1 Definitions of Terms Specific to This Standard:
B 341 Specification for Aluminum-Coated (Aluminized) 3.1.1 ACSR/TW covered by this specification has five types
Steel Core Wire for Aluminum Conductors, Steel Rein-
of coated core wire and one type of aluminum-clad core wire
forced (ACSR/AZ) which are designated by abbreviations as follows (Explanatory
B 354 Terminology Relating to Uninsulated Metallic Elec-
Note 2):
trical Conductors 3.1.1.1 ACSR/TW/AW—ACSR/TW using aluminum-clad
B 498 Specification for Zinc-Coated (Galvanized) Steel
steel wire (Specification B 502).
1 3
This specification is under the jurisdiction of ASTM Committee B-1 on Annual Book of ASTM Standards, Vol 14.02.
Electrical Conductors and is the direct responsibility of Subcommittee B01.07 on Annual Book of ASTM Standards, Vol 01.01.
Conductors of Light Metals. Available from American National Standards Institute, 11 West 42nd Street,
Current edition approved March 10, 1996. Published May 1996. Originally New York, NY 10036.
published as B 779 – 87. Last previous edition B 779 – 91. Available from National Technical Information Service, 5285 Port Royal Road,
Annual Book of ASTM Standards, Vol 02.03. Springfield, VA 22161.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
B 779–96
TABLE 1 Construction Requirements for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors, Coated Steel
Reinforced Size to Have Area Equal to ACSR, Class AA
ACSR/TW Conductor Size and Stranding of ACSR
Mass per
Steel Core Stranding
Number of Rated Nominal
Size with Equal Area
Number of Unit
Aluminum Strength, Outside
A
Layers Length,
B
Number of Diameter,
Wires 1000 lb Diameter, in.
kcmil Type kcmil Stranding
lb/1000 ft
Wires in.
336.4 6 336.4 18/1 14 2 1 0.1367 365 8.6 0.63
477.0 13 477.0 24/7 18 2 7 0.0940 613 17.2 0.78
477.0 16 477.0 26/7 18 2 7 0.1053 655 19.4 0.79
556.5 13 556.5 24/7 18 2 7 0.1015 715 20.0 0.84
556.5 16 556.5 26/7 20 2 7 0.1138 765 22.6 0.85
636.0 3 636.0 36/1 27 3 1 0.1329 646 13.5 0.85
636.0 13 636.0 24/7 18 2 7 0.1085 816 22.9 0.89
636.0 16 636.0 26/7 20 2 7 0.1216 874 25.4 0.91
795.0 7 795.0 45/7 17 2 7 0.0886 892 21.0 0.96
795.0 10 795.0 22/7 18 2 7 0.1108 975 25.9 0.98
795.0 13 795.0 54/7 20 2 7 0.1213 1021 28.2 0.99
795.0 16 795.0 26/7 20 2 7 0.1360 1092 31.8 1.01
954.0 5 954.0 42/7 30 3 7 0.0837 1029 23.7 1.05
954.0 7 954.0 45/7 32 3 7 0.0971 1075 25.9 1.06
954.0 13 954.0 54/7 20 2 7 0.1329 1226 33.5 1.08
1033.5 5 1033.5 42/7 30 3 7 0.0871 1115 25.7 1.09
1033.5 7 1033.5 45/7 32 3 7 0.1010 1165 28.1 1.10
1033.5 13 1033.5 54/7 21 2 7 0.1363 1327 36.3 1.13
1113.0 5 1113.0 42/7 30 3 7 0.0904 1201 27.5 1.13
1113.0 7 1113.0 45/7 33 3 7 0.1049 1254 30.3 1.14
1113.0 13 1113.0 54/19 38 3 19 0.0862 1429 39.1 1.19
1192.5 5 1192.5 42/7 30 3 7 0.0936 1286 29.5 1.17
1192.5 7 1192.5 45/7 33 3 7 0.1085 1343 32.4 1.18
1192.5 13 1192.5 54/19 38 3 19 0.0892 1530 41.9 1.22
1272.0 5 1272.0 42/7 30 3 7 0.0967 1372 31.4 1.20
1272.0 7 1272.0 45/7 35 3 7 0.1121 1433 34.6 1.22
1272.0 13 1272.0 54/19 39 3 19 0.0921 1632 44.1 1.26
1351.5 7 1351.5 45/7 35 3 7 0.1155 1522 36.7 1.26
1351.5 13 1351.5 54/19 39 3 19 0.0949 1734 46.8 1.30
1431.0 7 1431.0 45/7 36 3 7 0.1189 1613 38.9 1.29
1431.0 13 1431.0 54/19 39 3 19 0.0977 1836 49.6 1.34
1590.0 7 1590.0 45/7 36 3 7 0.1253 1792 42.2 1.36
1590.0 13 1590.0 54/19 42 3 19 0.1030 2040 55.1 1.41
1780.0 8 1780.0 84/19 37 3 19 0.0874 2063 50.7 1.45
2156.0 8 2156.0 84/19 64 4 19 0.0961 2515 61.1 1.61
A
Mass per unit length is based on Class A zinc-coated steel.
B
Rated strengths were calculated in accordance with 9.1 using steel stresses at 1 % for Class A coating in accordance with Specification B 498 (1 kip = 1000 lbf = 4.448
kN).
3.1.1.2 ACSR/TW/AZ—ACSR/TW using aluminum-coated 4. Ordering Information
(aluminized) steel wire (Specification B 341).
4.1 Orders for material under this specification shall include
3.1.1.3 ACSR/TW/GA—ACSR/TW using Class A zinc-
the following information:
coated steel wire (Specification B 498).
4.1.1 Quantity of each size,
3.1.1.4 ACSR/TW/GB—ACSR/TW using Class B zinc-
4.1.2 Conductor size: kcmil area and diameter,
coated steel wire (Specification B 498).
4.1.3 Conductor type and number of wires, aluminum and
3.1.1.5 ACSR/TW/GC—ACSR / TW using Class C zinc-
steel (Tables 1-3),
coated steel wire (Specification B 498).
4.1.4 Type of steel core wire and if zinc or Zn-5 % -MM
3.1.1.6 ACSR/TW/HS—ACSR/TW using extra high-
alloy coated, Class (A, B, and C) of coating (see 5.2),
strength steel wire (Specification B 606).
4.1.5 Special tension test, if required (see 9.2),
3.1.1.7 ACSR/TW/MA—ACSR/TW using Class A zinc-5 %
4.1.6 Place of inspection (Section 15),
aluminum-mischmetal alloy-coated steel core wire (Specifica-
4.1.7 Package size and type (see 16.1),
tion B 802).
4.1.8 Special package markings, if required (Section 16),
3.1.1.8 ACSR/TW/MB—ACSR/TW using Class B zinc-5 %
and
aluminum-mischmetal alloy-coated steel core wire (Specifica-
4.1.9 Heavy wood lagging, if required (see 16.3).
tion B 802).
5. Requirement for Wires
3.1.1.9 ACSR/TW/MC—ACSR/TW using Class C zinc-5 %
aluminum-mischmetal alloy-coated steel core wire (Specifica- 5.1 Before stranding, the trapezoidal aluminum wires (see
tion B 802). Terminology B 354) shall conform to the requirements of
3.1.1.10 ACSR/TW/MS—ACSR/TW using high-strength Specification B 230 except for shape and diameter tolerance.
zinc-5 % mischmetal alloy-coated steel core wire (Specifica- The tensile strength and elongation requirements of trapezoidal
tion B 803). wires shall be the same as for round wires of equal area. The
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
B 779–96
TABLE 2 Construction Requirements for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors, Coated Steel
Reinforced Sized to Have Diameter Equal to ACSR, Class AA
ACSR/TW Conductor Size and Stranding of ACSR
Mass
Steel Core Stranding
Number of Rated Nominal
Size with Equal Diameter
Number of per Unit
Aluminum Strength, Outside
A
Layers Length,
B
Number of Diameter,
Wires 1000 lb Diameter, in.
kcmil Type kcmil Stranding
lb/1000 ft
Wires in.
405.1 6 336.4 18/1 14 2 1 0.1520 441 10.2 0.68
571.7 13 477.0 24/7 18 2 7 0.1030 735 20.6 0.85
565.3 16 477.0 26/7 20 2 7 0.1146 776 22.9 0.86
666.6 13 556.5 24/7 20 2 7 0.1111 856 24.0 0.91
664.8 16 556.5 26/7 20 2 7 0.1244 913 26.6 0.93
768.2 13 636.0 24/7 20 2 7 0.1195 988 27.7 0.98
762.8 16 636.0 26/7 20 2 7 0.1331 1047 30.5 0.99
768.9 3 636.0 36/1 27 3 1 0.1520 785 16.4 0.93
957.2 7 795.0 45/7 32 3 7 0.0973 1079 26.0 1.06
946.7 10 795.0 22/7 35 3 7 0.1154 1142 29.6 1.08
966.2 13 795.0 54/7 21 2 7 0.1338 1241 34.0 1.09
959.6 16 795.0 26/7 22 2 7 0.1493 1318 37.0 1.11
1168.1 5 954.0 42/7 30 3 7 0.0926 1260 28.9 1.16
1158.0 7 954.0 45/7 33 3 7 0.1078 1308 31.6 1.17
1158.4 13 954.0 54/7 25 2 7 0.1467 1489 39.6 1.20
1272.0 5 1033.5 42/7 30 3 7 0.0967 1372 31.4 1.20
1257.1 7 1033.5 45/7 35 3 7 0.1115 1417 34.2 1.21
1233.6 13 1033.5 54/7 38 3 19 0.0910 1586 42.9 1.25
1372.5 5 1113.0 42/7 30 3 7 0.1004 1481 33.4 1.25
1359.7 7 1113.0 45/7 36 3 7 0.1159 1530 36.9 1.26
1334.6 13 1113.0 54/19 39 3 19 0.0944 1713 46.3 1.29
1467.8 5 1192.5 42/7 33 3 7 0.1041 1585 35.8 1.29
1455.3 7 1192.5 45/7 36 3 7 0.1200 1640 39.2 1.30
1433.6 13 1192.5 54/19 39 3 19 0.0978 1840 49.7 1.34
1569.0 5 1272.0 42/7 33 3 7 0.1074 1693 38.2 1.33
1557.4 7 1272.0 45/7 36 3 7 0.1241 1755 41.9 1.35
1533.3 13 1272.0 54/19 39 3 19 0.1012 1968 53.2 1.38
1657.4 7 1351.5 45/7 36 3 7 0.1280 1868 44.0 1.39
1622.0 13 1351.5 54/19 39 3 19 0.1064 2107 57.5 1.42
1758.6 7 1431.0 45/7 37 3 7 0.1319 1982 46.7 1.43
1730.6 13 1431.0 54/19 39 3 19 0.1075 2221 59.4 1.47
1949.6 7 1590.0 45/7 42 3 7 0.1392 2199 51.9 1.50
1926.9 13 1590.0 54/19 42 3 19 0.1133 2471 65.3 1.55
2153.8 8 1780.0 84/19 64 4 19 0.0961 2498 61.1 1.60
2627.3 8 2156.0 84/19 64 4 19 0.1062 3048 74.5 1.76
A
Mass per unit length is based on Class A zinc-coated steel.
B
Rated strength was calculated in accordance with 9.1 using steel stresses at 1 % for Class A coating in accordance with Specification B 498 (1 kip = 1000 lbf = 4.445
kN).
TABLE 3 Construction Requirements for Shaped Wire Compact Concentric-Lay Stranded Aluminum Conductors Coated, Steel
Reinforced
ACSR/TW Conductor
Steel Core Stranding
Number of Number Mass per Unit Rated Strength, Nominal Outside
Size
Aluminum Wires of Layers Length, lb/1000 ft 1000 lb Diameter, in.
kcmil Number of Wires Diameter, in.
795.5 17 2 7 0.0866 886.0 21.2 0.95
1109.7 17 2 7 0.0700 1132.0 23.6 1.10
1524.1 33 3 7 0.0966 1617.0 35.8 1.30
1935.4 31 3 7 0.0866 1958.0 41.0 1.45
area tolerances shall be such that the finished conductor wires during the stranding process. No weld shall occur within
conforms to Section 12.
50 ft (15 m) of any other weld in the completed conductor
5.2 Before stranding, the steel core wire shall meet the
(Explanatory Note 3).
requirements of Specifications B 341, B 498, B 502, B 606,
6.2 There shall be no joints made in the finished steel wires.
B 802, or B 803, whichever is applicable.
5.3 Following stranding, the steel core shall meet the
7. Lay
requirements of Specification B 500.
7.1 The preferred lay of the outside layer of aluminum wires
6. Joints
of shaped wire compact aluminum conductors, steel-
6.1 Electric-butt welds, electric-butt cold-upset welds, or reinforced, having a steel core of 7 or 19 wires and having
cold-pressure welds may be made in the individual aluminum multiple layers of aluminum wires, is 11 times the outside
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
B 779–96
TABLE 5 Rating Factors
diameter of the conductor but the lay shall not be less than 10
nor more than 13 times that diameter (Explanatory Note 4). Number of Layers Rating Factor, %
No. of Steel
7.2 The preferred lay of the layer immediately beneath the
Aluminum Steel
Wires
Aluminum Steel
outside layer of aluminum wires is 13 times the outside
Trapezoidal Round
diameter of such layer but the lay shall be not less than 10 nor
2 0 19596
more than 16 times that diameter.
2 1 79596
2 2 19 95 93
7.3 The lay of the inner layers of aluminum wires shall be
3 0 19396
not less than 10 nor more than 17 times the outside diameter of
3 1 79396
such layer.
3 2 19 93 93
4 2 19 92 93
7.4 The preferred lay of the 6-wire layer of 7- and 19-wire
steel cores is 25 times the outside diameter of the 6-wire layer
but the lay shall be not less than 18 nor more than 30 times that
number of aluminum layers, of the sum of the wire strengths
diameter.
calculated from the specified diameter of the round wires
7.5 The preferred lay of the 12-wire layer of 19-wire steel
having the same area as the trapezoidal wires used in the
core is 20 times the outside diameter of the core but the lay
manufacture of the conductor, and the appropriate minimum
shall be not less than 16 nor more than 24 times that diameter.
average tensile strength given in Specificatio
...