ASTM B779-18 - 1.3.2018
 
1. 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 Note 1 and Note 2).

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

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 (Table 1, Table 2 and Table 3). For the purpose of this specification, the sizes listed in Table 1 and Table 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 H 35.1. Aluminum 1350 corresponds to Unified Numbering System (UNS) A91350 in accordance with Practice E527.

(A) Code words shown in this column are obtained from Specification B1006. They are provided for information only.
(B) Mass per unit length is based on Class A zinc-coated steel. To convert to kg/km, multiply the lb/1000 ft value × 1.4887.
(C) Rated strengths were calculated in accordance with 9.1 using steel stresses at 1 % for Class A coating in accordance with Specification B498/B498M (1 kip = 1000 lbf  = 4.448 kN).
(D) To convert the diameter (inches) to mm, multiply the inch value × 25.4.
(E) To convert from kcmil to mm2 area, multiply the kcmil value × 5.067 × 10-4.
(F) For 795 kcmil Type 10 (Puffin ACSR TW) conductor the indicated 0.1108 in. steel wire size does not correspond with the concentric round wire 795 kcmil 22/7 Puffin ACSR conductor. The round wire construction utilizes a 0.1056” diameter steel core wire. The industry accepted dimension for the Puffin ACSR TW steel wire is 0.1108 in. Technically this renders the construction as a Type 11 conductor. The conductor mass, rated strength and diameter values correspond to the 0.1108 in. diameter steel core.
(A) Code words shown in this column are obtained from Specification B1006. They are provided for information only.
(B) To convert from kcmil to mm2 area, multiply the kcmil value x 5.067 x 10-4.
(C) Mass per unit length is based on Class A zinc-coated steel. To convert to kg/km, multiply the lb/1000 ft value x 1.4887.
(D) Rated strength was calculated in accordance with 9.1 using steel stresses at 1 % for Class A coating in accordance with Specification B498/B498M (1 kip = 1000 lbf = 4.445 kN).
(E) To convert the diameter (inches) to mm, multiply the inch value x 25.4.

1.3 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.

 
2. Referenced Documents

B230/B230M-22

Standard Specification for Aluminum 1350–H19 Wire for Electrical Purposes

B803-08

Standard Specification for High-Strength Zinc-5% Aluminum-Mischmetal Alloy-Coated Steel Core Wire for Use in Overhead Electrical Conductors

B606-08

Standard Specification for High-Strength Zinc-Coated (Galvanized) Steel Core Wire for Aluminum and Aluminum-Alloy Conductors, Steel Reinforced

B549-22

Standard Specification for Concentric-Lay-Stranded Aluminum Conductors, Aluminum-Clad Steel Reinforced for Use in Overhead Electrical Conductors

ANSI H35.1

American National Standard Alloy and Temper Designation Systems for Aluminum Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.

E29-22

Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications

E527-23

Standard Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)

B232/B232M-24

Standard Specification for Concentric-Lay-Stranded Aluminum Conductors, Coated-Steel Reinforced (ACSR)

B502-10

Standard Specification for Aluminum-Clad Steel Core Wire for Use in Overhead Electrical Aluminum Conductors

NBS Handbook 100

-- Copper Wire Tables of the National Bureau of Standards Available from National Technical Information Service (NTIS), 5285 Port Royal Rd., Springfield, VA 22161, http://www.ntis.gov.

B263-04

Standard Test Method for Determination of Cross-Sectional Area of Stranded Conductors

B354-23

Standard Terminology Relating to Uninsulated Metallic Electrical Conductors

B498/B498M-22

Standard Specification for Zinc-Coated (Galvanized) Steel Core Wire for Use in Overhead Electrical Conductors

B500/B500M-24

Standard Specification for Metallic Coated or Aluminum Clad Stranded Steel Core for Use in Overhead Electrical Conductors

B802/B802M-23

Standard Specification for Zinc–5 % Aluminum-Mischmetal Alloy-Coated Steel Core Wire for Use in Overhead Electrical Conductors