/images/buttons/swirl_60.jpg/images/southwire_100x70.jpgNew steel turns Southwire ACSS into high-temperature, low-sag conductornew-steel-turns-sw-acss-into-high-temp-low-sag-conductor.htm
Inscrivez-vous Maintenant Mot de Passe Oublié?

New steel turns Southwire ACSS into high-temperature, low-sag conductor

The venerable aluminum conductor,steel supported (ACSS) transmission line has been updated by Southwire with a new ultra-high-strength steel core that enables it to perform on par with more exotic high-temperature, low-sag conductors.

The new steel core for this product, called HS285® by Southwire, “lets us get more strength … without having to add a lot of weight,” Nick Ware, vice president-technical in Southwire’s energy division, told SNL Energy in late November. “In turn, that lets us pull the cable up tighter, because the strength is higher, and that helps sag performance.”

Carrollton, Ga.-based Southwire claims that the improved sag performance results in a 60% to 95% increase in available capacity over a standard utility aluminum conductor, steel reinforced (ACSR) transmission line of the same diameter.

Another advantage of HS285®, Ware said, is that it uses the same installation techniques as standard ACSS. HS285® carries a price premium, however. Ware said it costs about twice as much as ACSR and a little bit more than standard ACSS, “but quite a bit below any of the exotic composite core conductors.”

The product has been available commercially for a little over a year. Several sales have been made in the United States and Europe. Ware said he expects additional sales as utility engineers become familiar with the product and design it into future projects.

CenterPoint Energy Inc. in Texas is one of the first utilities to commit to install the HS285® conductor. Center-Point has been a big user of Southwire’s ACSS conductors, and since 2000 has been installing the latest generation of ACSS utilizing trapezoidal wires known as ACSS/TW.

CenterPoint will install HS285® conductor rated at 345 kV on a 40-mile segment of the 60-mile Hillje project. The Hillje project is an $80 million effort to increase transmission capacity between the South Texas Project nuclear plant near Bay City, Texas, and the W.A. Parish generating plant in Rosenberg, Texas. CenterPoint Manager of Transmission Engineering Chuck Bennett told SNL Energy in December that about half of the conductor had been delivered and foundations for the first 10 of 100 transmission structures had been prepared.

He said he expected contractor Infra-Source to begin pulling the wire by March in order to meet a May 15, 2007, deadline for putting the transmission line in service.

Before deciding to go ahead with this new product, CenterPoint contracted with the Electric Power Research Institute to test the conductor. Testing covered mechanical strength of the conductor and mechanical and thermal performance of the conductor and associated line support accessories.

“[CenterPoint] sees [HS285®] conductors as a continuing economical technology solution for meeting increasing transmission capacity needs,” the utility said in a background paper. “[We] will evaluate … HS285® on a project basis for future applications because even though it sags less than the original ACSS/TW, it presently carries a higher price