XLPE, Cross-linked polyethylene, has stable intermolecular bonds between polyethylene particles created by thermochemical action, due to the presence of organic peroxide.
XLPE has the same electricl properties as the conventional polyethylene and as result of stable intermolecular bonds, has much better thermal and mechanical properties. This provides XLPE insulated cables to be used at maximum continuous conductor temperature of 90°C while conventional polyethylene insulated cables to be used at that of 75°C. Maximum overload conductor operating temperature is 130°C ( operating at the emergency overload temperature shall not exceed 100 hours per year). Maximum conductor short-circuit temperature is 250°C. This provides an important advantage in cable ratings and is of special significance in countries or situations where the ambient temperature is high and derating factors have to be applied.
The cross-linking tehnology is based on entirely "dry" cross-linking and cooling process. This eliminates micro inclusions of water from the insulation which, unless prevented, lead to so called "water treeing" effect. A triple crosshead extrudes the screen over the conductor and screen over insulation in a single technological operation. All that gives the cable excellent electrical, thermal and mechanical properties.

APPLICATION
XLPE-insulated cables can be used for nearly all installations : in the ground, in cable ducts, indoors, in power stations, in industrial plants , in switching stations. Thanks to their better thermal characteristics they are particularly recommended where :
- high ambient temperatures exict
- cables are exposed to the sun
- cables are laid in ducts in a concrete block
- cables are grouped
- high emergency loads are important
- high short-circuit currents are required
- high earth leakage currents have to be transmitted by the screens

Cable types:

High voltage cables (69-150 kV)