ASTM B229-12(2023)

Standard Specification for Concentric-Lay-Stranded Copper and Copper-Clad Steel Composite Conductors

ABSTRACT
This specification covers concentric-lay-stranded conductors made from uncoated hard-drawn round copper wires in combination with hard-drawn round copper-clad steel wires for general use as overhead electrical conductors. The conductors are classified under the following type designations: Type A, Type C, Type D, Type E, Type EK, Type F, Type G, Type J, Type K, Type N, Type P, and Type V. Welds and brazes may be made in copper rods or in copper wires prior to final drawing. Joints may not be made in the finished copper wires composing concentric-lay-stranded composite conductors containing a total of seven wires or less. In other conductors, welds and brazes may be made in the finished individual copper wires composing the conductor. Also, the joints or splices may be made in the finished individual copper-clad steel wires composing concentric-lay-stranded conductors, provided that such joints or splices have a protection equivalent to that of the wire itself and that they do not decrease the strength of the finished stranded conductor below the minimum breaking strength. The density, mass, and resistance of the wires shall be determined.
SCOPE
1.1 This specification covers concentric-lay-stranded conductors made from uncoated hard-drawn round copper wires in combination with hard-drawn round copper-clad steel wires for general use as overhead electrical conductors.  
1.2 For the purpose of this specification, conductors are classified under the following type designations (see Fig. 1):    
Type A  
Type G  
Type C  
Type J  
Type D  
Type K  
Type E  
Type N  
Type EK  
Type P  
Type F  
Type V
FIG. 1 Standard Types of Composite Conductors  
1.3 The SI values for density are regarded as the standard. For all other properties the inch-pound values are to be regarded as standard and the SI units may be approximate.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Sep-2023
• ICS: 29.060.20 - Cables
• Technical Committee: B01 - Electrical Conductors
• Drafting Committee: B01.06 - Bi-Metallic Conductors

Relations

• Replaces: ASTM B229-12(2017) - Standard Specification for Concentric-Lay-Stranded Copper and Copper-Clad Steel Composite Conductors
• Effective Date: 01-Oct-2023

Overview

ASTM B229-12(2023) is a standard specification developed and published by ASTM International for concentric-lay-stranded copper and copper-clad steel composite conductors. This standard applies to uncoated, hard-drawn round copper wires combined with hard-drawn round copper-clad steel wires, primarily intended for use as overhead electrical conductors. It provides requirements on conductor types, construction, material, and performance to ensure suitability for general electrical transmission and distribution applications.

By adhering to internationally recognized principles on standardization, this specification helps ensure interoperability, reliability, and safety for composite electrical conductors across various industries and regions.

Key Topics

• Scope and Application: Specifies the use of concentric-lay-stranded conductors made from a combination of copper and copper-clad steel wires for overhead electric power lines.
• Conductor Types: Identifies multiple conductor types (A, C, D, E, EK, F, G, J, K, N, P, V) with different constructions and properties, allowing for selection based on application needs.
• Joints and Splices: Defines guidelines for making welds and splices within the conductors, including permitted joint types and protective measures, to ensure electrical continuity and mechanical performance.
• Material Requirements: References ASTM specifications (such as B1 for copper wire and B227 for copper-clad steel wire) for ensuring the quality and consistency of component materials.
• Physical and Electrical Testing: Outlines testing requirements for physical (tensile strength, elongation) and electrical properties (resistance, continuity) to verify conductor quality before and after stranding.
• Construction and Lay: Specifies construction parameters such as wire numbers, diameters, and lay directions for different conductor types, supporting standardized installation and maintenance.
• Density, Mass, and Resistance: Establishes methods for calculating density, mass per unit length, and electrical resistance, which are critical for design and selection.
• Packaging and Marking: Details packaging sizes and marking requirements for identification and traceability during shipping and storage.

Applications

The ASTM B229-12(2023) standard is widely used in the electrical utility and power transmission sectors due to its focus on overhead applications. Typical applications include:

• Overhead Power Transmission Lines: The primary use of these composite conductors, combining the conductivity of copper with the high tensile strength of copper-clad steel, is in the construction of reliable and durable overhead power lines.
• Electrical Distribution Networks: Where improved mechanical strength is required, especially in long spans or challenging environmental conditions.
• Infrastructure and Utility Projects: Used in municipal, rural, and industrial energy delivery systems that require standardized, high-quality conductor products.
• Retrofit and Upgrade Projects: Particularly beneficial when upgrading existing lines to improve performance or extend service life by using composite conductors.

Benefits of specifying conductors to ASTM B229-12(2023) include improved mechanical properties, resistance to corrosion, reliability in service, and alignment with international best practices for electrical safety and performance.

Related Standards

When applying or selecting conductors per ASTM B229-12(2023), the following standards are commonly referenced to ensure full compliance and optimal implementation:

• ASTM B1: Specification for Hard-Drawn Copper Wire
• ASTM B227: Specification for Hard-Drawn Copper-Clad Steel Wire
• ASTM B354: Terminology Relating to Uninsulated Metallic Electrical Conductors
• ANSI C42: Definitions of Electrical Terms
• NBS Handbook 100: Copper Wire Tables

These related standards provide supplementary requirements and guidance on material quality, testing methods, and terminology, supporting the implementation of composite conductors as specified in ASTM B229-12(2023).

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Keywords: ASTM B229, concentric-lay-stranded copper conductor, copper-clad steel conductor, overhead electrical conductor specification, composite conductors, power transmission standards, electrical standards.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: B229 − 12 (Reapproved 2023)
Standard Specification for
Concentric-Lay-Stranded Copper and Copper-Clad Steel
Composite Conductors
This standard is issued under the fixed designation B229; 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 2.2 ANSI Standard:
C 42 Definitions of Electrical Terms
1.1 This specification covers concentric-lay-stranded con-
2.3 National Institute of Standards and Technology:
ductors made from uncoated hard-drawn round copper wires in
NBS Handbook 100—Copper Wire Tables
combination with hard-drawn round copper-clad steel wires for
general use as overhead electrical conductors.
3. Ordering Information
1.2 For the purpose of this specification, conductors are
3.1 Orders for material under this specification shall include
classified under the following type designations (see Fig. 1):
the following information:
Type A Type G
3.1.1 Quantity of each size and type;
Type C Type J
3.1.2 Conductor size: hard-drawn copper equivalent in
Type D Type K
Type E Type N circular-mil area or AWG (Section 7 and Table 1);
Type EK Type P
3.1.3 Type (see 1.2, Fig. 1, and Table 1);
Type F Type V
3.1.4 Direction of lay of outer layer, if other than left-hand
1.3 The SI values for density are regarded as the standard.
(see 6.3);
For all other properties the inch-pound values are to be
3.1.5 When physical tests shall be made (see section 8.2);
regarded as standard and the SI units may be approximate.
3.1.6 Package size (see 14.1);
3.1.7 Special package marking, if required (Section 15);
1.4 This international standard was developed in accor-
3.1.8 Lagging, if required (see 14.2); and
dance with internationally recognized principles on standard-
3.1.9 Place of inspection (Section 13).
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
4. Material for Wires
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee. 4.1 The purchaser shall designate the size and type of
conductor to be furnished. The position of the hard-drawn
copper wires and the copper-clad steel wires in the conductor
2. Referenced Documents
cross section shall be as shown in Fig. 1.
2.1 ASTM Standards:
4.2 Before stranding, the wire used shall meet the require-
B1 Specification for Hard-Drawn Copper Wire
ments of Specifications B1 and B227 that are applicable to its
B227 Specification for Hard-Drawn Copper-Clad Steel Wire
type.
B354 Terminology Relating to Uninsulated Metallic Electri-
cal Conductors
5. Joints
E29 Practice for Using Significant Digits in Test Data to
Determine Conformance with Specifications 5.1 Copper—Welds and brazes may be made in copper rods
or in copper wires prior to final drawing. Joints may not be
made in the finished copper wires composing concentric-lay-
stranded composite conductors containing a total of seven
This specification is under the jurisdiction of ASTM Committee B01 on
wires or less. In other conductors, welds and brazes may be
Electrical Conductors and is the direct responsibility of Subcommittee B01.06 on
Bi-Metallic Conductors.
made in the finished individual copper wires composing the
Current edition approved Oct. 1, 2023. Published October 2023. Originally
approved in 1948. Last previous edition approved in 2017 as B229 – 12 (2017).
DOI: 10.1520/B0229-12R23.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM 4th Floor, New York, NY 10036, http://www.ansi.org.
Standards volume information, refer to the standard’s Document Summary page on Available from National Institute of Standards and Technology (NIST), 100
the ASTM website. Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http://www.nist.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B229 − 12 (2023)
in position when the conductor is cut at any point and shall
permit restranding by hand after being forcibly unraveled at the
end of the conductor.
7. Construction
7.1 The numbers and diameters of wires in the various types
of concentric-lay-stranded composite conductors shall conform
to the requirements prescribed in Table 1 (Explanatory Note 2).
8. Physical and Electrical Tests
8.1 Tests for the physical and electrical properties of wires
composing concentric-lay-stranded composite conductors shall
be made before but not after stranding.
8.2 At the option of the purchaser or his representative,
tension and elongation tests on wires before stranding may be
waived, and the completed conductor may be tested as a unit.
The breaking strength of the conductors so tested shall be not
less than the rated strength values shown in Table 2. The free
length between grips of the test specimen shall be not less than
24 in. (0.61 m), and care shall be taken to ensure that the wires
in the conductor are evenly gripped during the test (Explana-
tory Note 3).
9. Density
9.1 For the purpose of calculating weights, cross sections,
and so forth, the density of the copper shall be taken as 8.89
FIG. 1 Standard Types of Composite Conductors
g/cm at 20 °C (Explanatory Note 4 and Table 2).
9.2 The density of both types of copper-clad-steel wire shall
be taken as stated in Table 2.
conductor, but shall be not closer than 50 ft (15 m) to any other
10. Mass and Resistance
joint in the same layer in the conductor.
10.1 The mass and electrical resistance of a unit length of
5.2 Copper-Clad Steel—Joints or splices may be made in
stranded conductor are a function of the length of lay. The
the finished individual copper-clad steel wires composing
approximate mass and electrical resistance may be determined
concentric-lay-stranded conductors, provided that such joints
using the standard increments shown in Table 3. When greater
or splices have a protection equivalent to that of the wire itself
accuracy is desired, the increment based on the specific lay of
and that they do not decrease the strength of the finished
the conductor may be calculated (Explanatory Note 6). Refer-
stranded conductor below the minimum breaking strength
ence information is shown in Table X1.1 in Appendix X1.
shown in Table 1. Such joints or splices shall be not closer than
50 ft (15 m) to any other joint in the same layer in the
11. Variation in Area
conductor (Explanatory Note 1).
11.1 The area of cross section of the completed conductor
shall be not less than 97 % of the nominal area. The area of
6. Lay
cross section of a conductor shall be considered to be the sum
6.1 For Types A, C, and D conductors, the preferred lay is
of the cross-sectional areas of its component wires at any point
approximately 16.5 times the outside diameter of the com-
when measured perpendicularly to their axes (Explanatory
pleted conductor, but shall be not less than 13 nor more than 20
Note 8). For the purposes of determining conformance to this
times this diameter.
standard, a measured or calculated value for cross sectional
6.2 For all other types, the preferred lay of a layer of wires area shall be rounded to four significant figures in accordance
is 13.5 times the outside diameter of that layer, but shall be not
with the rounding method of Practice E29.
less than 10 nor more than 16 times this diameter.
12. Finish
6.3 The direction of lay of the outer layer shall be left-hand
12.1 The conductor shall be free of all imperfections not
unless the direction of lay is specified otherwise by the
consistent with the best commercial practice.
purchaser.
6.4 The direction of lay shall be reversed in successive 13. Inspection
layers.
13.1 Unless otherwise specified in the contract or purchase
6.5 All wires in the conductor shall lie naturally in their true order, the manufacturer shall be responsible for the perfor-
positions in the completed conductor. They shall tend to remain mance of all inspection and test requirements specified.
B229 − 12 (2023)
TABLE 1 Construction Requirements and Breaking Strength of Concentric-Lay-Stranded Copper and Copper-Clad Steel Composite
Conductors
NOTE 1—Metric Equivalents—For conductor size, 1 cmil = 0.0005067 mm (round to four significant figures); for diameter 1 mil = 0.02540 mm
(round to four significant figures); for breaking strength, 1 lb = 0.45359 kg (round to four significant figures).
Conductor Size, Hard-Drawn Copper Hard-Drawn Copper
Grade 30 EHS Copper-Clad Steel Wires
A Rated Breaking
Equivalent Wires
Type Strength, min,
Number of Diameter of Number of Diameter of B
lb
cmil AWG
Wires Wires, mils Wires Wires, mils
350 000 . . . E 7 157.6 12 157.6 32 420
350 000 . . . EK 4 147.0 15 147.0 23 850
350 000 . . . V 3 175.1 9 189.3 23 480
300 000 . . . E 7 145.9 12 145.9 27 770
300 000 . . . EK 4 136.1 15 136.1 20 960
300 000 . . . V 3 162.1 9 175.2 20 730
250 000 . . . E 7 133.2 12 133.2 23 920
250 000 . . . EK 4 124.2 15 124.2 17 840
250 000 . . . V 3 148.0 9 160.0 17 420
211 600 0000 E 7 122.5 12 122.5 20 730
211 600 0000 G 2 194.4 5 194.4 15 640
211 600 0000 EK 4 114.3 15 114.3 15 370
211 600 0000 V 3 136.1 9 147.2 15 000
211 600 0000 F 1 183.3 6 183.3 12 290
167 800 000 E 7 109.1 12 109.1 16 800
167 800 000 J 3 185.1 4 185.1 16 170
167 800 000 G 2 173.1 5 173.1 12 860
167 800 000 EK 4 101.8 15 101.8 12 370
167 800 000 V 3 121.2 9 131.1 12 200
167 800 000 F 1 163.2 6 163.2 9980
133 100 00 K 4 178.0 3 178.0 17 600
133 100 00 J 3 164.8 4 164.8 13 430
133 100 00 G 2 154.2 5 154.2 10 510
133 100 00 V 3 108.0 9 116.7 9846
133 100 00 F 1 145.4 6 145.4 8094
105 600 0 K 4 158.5 3 158.5 14 490
105 600 0 J 3 146.7 4 146.7 10 970
105 600 0 G 2 137.3 5 137.3 8563
105 600 0 F 1 129.4 6 129.4 6536
83 690 1 N 5 154.6 2 154.6 15 410
83 690 1 K 4 141.2 3 141.2 11 900
83 690 1 J 3 130.7 4 130.7 9000
83 690 1 G 2 122.2 5 122.2 6956
83 690 1 F 1 115.3 6 115.3 5266
66 360 2 P 6 154.0 1 154.0 16 870
66 360 2 N 5 137.7 2 137.7 12 680
66 360 2 K 4 125.7 3 125.7 9730
66 360 2 J 3 116.4 4 116.4 7322
66 360 2 A 1 169.9 2 169.9 5876
66 360 2 G 2 108.9 5 108.9 5626
66 360 2 F 1 102.6 6 102.6 4233
52 620 3 P 6 137.1 1 137.1 13 910
52 620 3 N 5 122.6 2 122.6 10 390
52 620 3 K 4 112.0 3 112.0 7910
52 620 3 J 3 103.6 4 103.6 5955
52 620 3 A 1 151.3 2 151.3 4810
41 740 4 P 6 122.1 1 122.1 11 420
41 740 4 N 5 109.2 2 109.2 8460
41 740 4 D 2 161.5 1 161.5 7340
41 740 4 A 1 134.7 2 134.7 3938
33 090 5 P 6 108.7 1 108.7 9311
33 090 5 D 2 143.8 1 143.8 6035
33 090 5 A 1 120.0 2 120.0 3193
26 240 6 D 2 128.1 1 128.1 4942
26 240 6 A 1 106.8 2 106.8 2585
C
26 240 6 C 1 104.6 2 104.6 2143
20 820 7 D 2 114.1 1 114.1 4022
20 820 7 A 1 126.6 2 89.5 2754
B229 − 12 (2023)
TABLE 1 Continued
Conductor Size, Hard-Drawn Copper Hard-Drawn Copper
Grade 30 EHS Copper-Clad Steel Wires
A Rated Breaking
Equivalent Wires
Type Strength, min,
Number of Diameter of Number of Diameter of B
lb
cmil AWG
Wires Wires, mils Wires Wires, mils
16 510 8 D 2 101.6 1 101.6 3256
16 510 8 A 1 112.7 2 79.7 2233
C
16 510 8 C 1 80.8 2 83.4 1100
C
11 750 9 ⁄2 D 2 80.8 1 80.8 1330
A
See Explanatory Note 7.
B
See Explanatory Note 11.
C
Grade 40 HS (all of the other CCS wire is Grade 30 EHS).
TABLE 2 Density of Copper and Copper-Clad Steel
Density at 20 °C
Units
Copper 30 % Copper-Clad Steel 40 % Copper-Clad Steel
Grams per cubic centimetre 8.89 8.15 8.24
Pounds per cubic inch 0.3212 0.2944 0.2975
Pounds per circular mil-foot 0.0000030270 0.0000027750 0.0000028039
TABLE 3 Standard Increments Due to Stranding
14.2 The conductors shall be protected against damage in
Increment (Increase) of ordinary handling and shipping. If heavy wood lagging is
Type of Conductor
Resistance and Weight, %
required, it shall be specified by the purchaser at the time of
A, C, and D 0.8
purchase.
F, G, J, K, N, and P 1.0
V 1.2
15. Marking
E and EK 1.4
15.1 The net mass, length (or lengths, and number of
lengths, if more than one length is included in the package),
13.2 All inspections and tests shall be
...