The overhead conductor industry needs an Standard covering the Carbon Fiber Thermoset Polymer Matrix Composite Core (CFC), which is widely-used in a product designated Aluminum Conductor Fiber Reinforced (AFCR) overhead conductor. AFCR has a proven record in both utility installations and laboratory testing. AFCR was first installed in an operating overhead line by a utility in 1997. After a two-year demonstration, the CFC core was evaluated and found to have negligible aging. A second demonstration line ran from December 2002 until January 2019 (15 years), again with negligible aging of the core.
In addition to the demonstration lines and subsequent successful commercial installations, AFCR has passed all of the industry-standard tests for conductors with composite cores.
AFCR is marketed by a major US overhead conductor supplier. AFCR is also manufactured internationally by stranding partners of the core manufacturer. There are numerous installations and additional commercial sales pending. To date there are no technical issues or line failures associated with the AFCR conductor. A consensus Standard for AFCR core is needed as a first step in a Standard for AFCR overhead conductor.
AFCR core complies with most ASTM B987/B987M requirements, but differs in three areas:
1) B978 describes a monofilament (single-strand) core. AFCR is available only in 7-strand, and potentially higher strand counts. This confers benefits in terms of bending limits, flexibility, and damage tolerance.
2) The materials and methods for galvanic protection of the aluminum conductor component are different, but are demonstrably equivalent to the materials and methods stipulated in ASTM B987.
It is proposed to add the AFCR core design to ASTM B987 as an additional grade of CFC core for overhead conductors. A previous effort for a stand-alone AFCR core Standard failed due to industry confusion with the similar existing Standard (B997). B987 is, by intent and title, for Carbon Fiber Thermoset Polymer Matrix Composite Core (CFC). This is the exact description for the AFCR core proposed for addition to the existing Standard.
Developed by Subcommittee: B01.07
Staff Manager: Nora Nimmerichter
Date Initiated: 03-04-2022
Technical Contact: Paul Springer
Ballot: B01 (22-04)
Status: In Balloting