Introduction to XLPE insulated cables
XLPE or Cross-linked polyethylene is a thermoset insulation material. Crosslinking polymers is a process which changes the molecular structure of the polymer chains so that they are more tightly bound together and this crosslinking is done either by chemical means or physical means. Chemical crosslinking involves the addition of chemicals or initiators such as silane or peroxide to generate free radicals which form the crosslinking. Physical crosslinking involves subjecting the polymer to a high energy source such as high-energy electron or microwave radiation.
Polyethylene (PE) material itself has excellent dielectric strength, high insulation resistance, and a low dissipation factor at all frequencies making it an ideal insulator, however it is limited in its temperature range. Cross-linking the PE to become XLPE increases the temperature range of the insulation whilst maintaining the electrical properties.
XLPE VS PVC CABLE INSULATION
XLPE is suitable for voltage ranges from low to extra high voltage, surpassing other insulation materials such as PVC, Ethylene Propylene Rubber (EPR) and silicone rubbers. Cross-linking the polyethylene also enhances the chemical and oil resistance at elevated temperatures and makes it suitable for use as a Low Smoke Zero Halogen material.
The mechanical properties of the XLPE are superior to many other insulations, offering greater tensile strength, elongation and impact resistances. The addition of carbon black can be used to further enhance hot deformation and cut through resistance. The XLPE insulation will not melt or drip, even at the temperatures of soldering irons, and it has increased flow resistance and improved ageing characteristics.
Improved water-tree resistance is another benefit of XLPE insulation for LV cables and MV cables over PE insulations. Water treeing is a defect which is the result of imperfections in the insulation where fracture lines occur and grow in the direction of the electric field, increasing with electrical stress. It should be noted that this effect is not limited to PE materials.
XLPE insulated cables manufacturer recommendation
There is an excellent XLPE insulated cables manufacturer - Shenghua Cable Co., Ltd., which sells high-quality cables. If you want to know more about XLPE insulated cables, or are interested in our products, you can visit the website of Shenghua Cable Co., Ltd.
