Insulation compound chemistry has come a long way in todays market. The chemistry for cross-linked polyethylene (XLPE) and ethylene propylene rubber (EPR) changed in the 1960s so modern XLPE and EPR insulations use catalysts that chemically cross-link the molecular chains yet do not corrode the conductor. Similarly, advances in semi-conducting shield compounds deliver far better stripability with bare copper conductors. Corrosion is another reason tinning is considered. Today, there are special electrical contact lubricants such as NO-OX that prevents the formations of oxide films at termination points making tinning less desirable. In conclusion, unless the power cable installation is in an environment that is continuously exposed to corrosive elements (as is the case in certain wastewater treatment facilities), copper conductor tinning is a practice that is no longer required with today’s cable compounds, corrosion lubricants and manufacturing technology. It’s an added cost that also requires longer lead times and minimum run quantities. And since it is an environmentally unfriendly process, any reduction in conductor tinning helps to make our environment better.
Author archives: Sy Shaheen
Southwire® Industrial Power Cable products do not have a defined shelf life. These products are composed of hard goods (metal, polymer, etc., ...) that are designed for many years of service once installed. As long as the products are not damaged during storage/handling and they are stored in a facility that protects against exposure to weather (sunlight and precipitation), there should be no degradation to the electrical and mechanical performance of the products and no reduction in service life. When storing cable the following precautions should be considered
Strand-fll sometimes called moisture-block is a tar like substance that is applied between each lay-er of a concentric stranded copper or aluminum phase conductor. During the stranding process and at slightly elevated temperatures this tar like substance becomes fuid enough to be forced through a pump and applied geometrically in such a manner that the interstitial space between every strand is flled with the tar. The tar is then allowed to cool whereas it becomes stable and remains in place.
A dual rated cable is a cable that lists two different voltage ratings on its jacket. For instance, a cable with 115 mils insulation thickness may have a jacket with a print legend that lists both 5kV and 8kV voltages at 133% and 100% insulation levels respectively on it. Therefore, this cable may be used on both 5kV and 8kV systems.
Southwire is a company with a keen environmental awareness. We seek to leave the lightest footprint possible on the environment in the course of manufacturing and delivering our products to market. To that end Southwire Company has innovated a product that accomplishes one of our environmental objectives – A medium and 600 volt Ethylene Propylene Rubber (EPR) insulation that contains no lead.