Steel Core Wire
Two new ASTM International standards for steel core wire will be useful in providing transmission cable that will make the most of the existing infrastructure in gaining electrical transmission efficiency.
“The products in these standards allow electrical utilities and transmission cable designers more flexibility to increase electrical transmission capacity with minimal investments,” says Dale King, customer technical relations manager, Bekaert Corp. “This ultimately results in lower costs to the general public.”
The standards — B957, Specification for Extra-High-Strength and Ultra-High-Strength Zinc-Coated (Galvanized) Steel Core Wire for Overhead Electrical Conductors, and B958, Specification for Extra-High-Strength and Ultra-High-Strength Class A Zinc-5% Aluminum-Mischmetal Alloy-Coated Steel Core Wire for Use in Overhead Electrical Conductors — were developed by Subcommittee B01.05 on Conductors of Ferrous Metals, part of ASTM International Committee B01 on Electrical Conductors.
According to King, increasing demands for electricity, combined with a decreasing availability of system expansion resources, has created the need for electrical utilities to find ways to maximize existing infrastructure to gain electrical transmission efficiency. “One way to achieve this is to make an electrical transmission cable that can be installed in such a way to allow higher operating temperatures without sacrificing safety or limiting the cable life,” says King, who is chair of Subcommittee B01.05. “The limiting factor has always been the steel strength and temperature resistance.”
However, the development of new steels and coatings, as covered in B957 and B958, allows utilities and transmission cable designers more flexibility to increase electrical transmission capacity with minimal investments. Electrical transmission cable manufacturers will be the primary users of the standards.
Technical Information: Dale King, Bekaert Corp., Van Buren, Ark.
Phone: 479-474-5211, ext. 174
ASTM Staff: Jennifer Rodgers