500kV XLPE Insulated Power Cable

Rated voltage 500kV cross-linked polyethylene insulated power cables are featured
with high allowable working temperature of conductors, huge transmission capacity,
excellent electric properties, simple cable accessories and convenient installment
and laying, so they are widely used in the power system today.

The cable can be applied to the neutral-point solid grounded power transmission line
system with A.C. rated voltage (U0/U) = 290/500kV and the maximal system voltage
Um=550kV.

Features:
1) Conductor: conductor is made up of copper or aluminum. Cables below
    800mm2 stranded by drawing and pressing, are characterized with
    smooth, round and high pressing coefficient; cables 800mm2 and above applied
    with conductor separation to reduce the skin effect and to increase the
    transmission capacity
2) Semi-conducting screen: unstripable and super-smooth cross-linked semi-
    conducting materials are used in both the conductor screen and the insulation
    screen. The three layers of conductor screen, insulation layer and insulation
    screen are co extruded to keep the close link between the insulation layer and 
    the semi-conducting layer and keep the interface smooth
3) Insulation: super-purified insulation materials are used and the purification
    degree of feeding room reaches 1000. Moreover, in the production process,    
    complete-sealing MOTAN feeding system is used to ensure the purity of materials.  
    And SIKORA on-line eccentricity control system is adopted to monitor the insulation
    eccentricity. Eccentricity degree of insulation layer shall not exceed 8%, i.e.
    (tmax- tmin)/ tmax X100% ≤8%
4) Buffer layer and longitudinal water-resistant layer: buffer layer adopts semi-
    conducting flexible materials or flexible water-resistant expansion materials
    with longitudinal water-resistant performance to wrap between the insulation 
    screen and the corrugated aluminum sheath to satisfy and compensate for the 
    thermal-expansion during the operation of cables
5) Corrugated aluminum sheath: corrugated aluminum sheath is made of aluminum
    with purity of no less than 99.6%, extension rate of soft aluminum pipe no less
    than 16% to meet the needs of mechanical properties and short-circuit capacity
    and has radial water-resistant performance. Welding corrugated aluminum sheath
    should pass the air-tight test. Screen thread of the aluminum sheath is either
    spiral or circular and that of the water-resistant cables is circular
6) Separation layer: outer of the aluminum sheath is applied with asphalt
    anticorrosive coating and wrapped water-resistant belt
7) Outer sheath: the outer sheath of cables is made of polyvinyl chloride or
    polyethylene, and the double-layer co extrusion technology is used to extrude
    the semi-conducting layer to the surface of the outer layer of cables. Anti-flaming
    or termite-proof corrosive type is for your choice