ASTM B779-22

ABSTRACT 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. Requirements for (1) wire stranding (2) tensile strength and elongation, (3) joints such as electric-butt welds, electric-butt cold-upset welds, or cold-pressure welds, and (4) lay length, diameter, direction, and factor are detailed. The construction requirements include: nominal aluminum cross sectional area, conductor type, nominal number of aluminum wires, number of layers, number and diameter of the steel core wire, mass per unit length, rated strength, and outside diameter of the shaped wire compact. The methods of determining mass per unit length, cross-section, and electrical resistance of the stranded conductor are given. Mechanical and electrical tests shall be performed before stranding. 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. 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.