Brief introduction of copper clad aluminum wire and cable products (Technology)

    At present, the price of non-ferrous metals is soaring, and the cost of copper conductor accounts for more than 90% of the total cost of cable raw materials. In order to not only meet the technical index of copper conductor of cable, but also greatly reduce the cost of cable, our company has developed copper-clad aluminum power cable and wires and cables for electrical equipment based on the original production of copper-clad aluminum conductor according to the market demand.
Advantages of the product:

    1. DC resistivity: the resistivity of copper-clad aluminum wire is larger than that of pure copper wire, about 1.5 times of that of pure copper wire. When the resistance value is the same (the cross-sectional area is larger than that of copper), the weight of copper-clad aluminum wire is about 1 / 2 of that of pure copper wire. According to the calculation of skin effect, the resistivity of copper conductor is equal to that of copper conductor with the same cross section at high frequency above 50MHz. In the use of power cable with 50 Hz frequency, the skin effect and proximity effect of copper conductor are more and more prominent when it is over 150 mm ~ 2. At the same time, due to the start-up and operation faults of equipment power (such as high-frequency furnace, high-power motor, etc.) in industrial and mining enterprises, the energy generating high-order harmonic current will be injected into the power supply system, and the corresponding high-order harmonic current will be generated in the impedance of the system In addition, the cable amplifies the harmonic wave and produces overvoltage at the joint, which damages the cable head. The use of copper-clad aluminum conductor can reduce the AC impedance (resistance) caused by high-order harmonics. In other applications, by improving the volume of copper in copper-clad aluminum monofilament and the corresponding process measures, the copper-clad aluminum conductor can meet the requirements of conductor DC resistance within the upper limit of the outer diameter of the existing conductors of the same specification.
    2. The adoption of copper-clad aluminum conductor can meet the habit of product selection, design, use and installation of wires and cables for many years. It is also beneficial to the tight pressing and tin welding of cable terminals.
    3. Reduce AC resistance:
        3.1、 AC resistance is the main basis of current carrying capacity. According to the principle of skin effect, the current per unit area on the surface of a single wire is larger than that on the center of the wire. That is to say, the center of a large cross-section conductor is in the circle area composed of the same conductor, and the center of the circle is smaller than that of the circle. Therefore, the center conductor is different from the circle conductor The composition of the metal is the most reasonable and economical.
        3.2、 Besides DC resistance, skin effect and proximity effect, the AC resistance index should be affected. Compared with copper conductor with the same DC resistance, copper-clad aluminum conductor with enlarged cross section should be adopted. In a single conductor, aluminum is in the center of the circle and copper is in the outer circle. The enlarged copper-clad aluminum conductor increases the surface area of the conductor and improves the heat dissipation strip of the cable due to the increase of the total cross section of the conductor The thermal conductivity of aluminum is similar to that of copper. Under the same material cost, the index of AC resistance is much more economical.
    4. It has good corrosion resistance: aluminum is easier to corrode than copper, but because the copper-clad aluminum material has been fully metallurgic, aluminum is difficult to be used
It is completely covered by copper, and will not be contacted by water and air, so it has the same performance as copper. For aluminum conductors, especially in coastal areas, chloride ions contained in atmospheric salt spray will condense on the surface of aluminum, which is easy to cause local corrosion around impurities and defects on the surface, forming holes, cracks and micro cells, and aggravating the corrosion of aluminum conductors.
    5. Low cost and light weight: compared with copper wire with the same technical index, copper clad aluminum conductor cable can save more than 40% of the cost. The proportion of copper clad aluminum wire is only 37% - 40% of that of pure copper wire, and its length is 2.5 times of that of pure copper wire when the wire diameter and weight are equal.
    6. Good solderability: copper clad aluminum wire has the same solderability as pure copper wire because its surface is concentric coated with a layer of pure copper, which is convenient for production.

Application scope and product features of copper clad aluminum conductor wires and cables

    Scope of application
    PVC insulated wires and cables with rated voltage of 450 / 750V (below 1KV) and below are suitable for lighting with rated AC voltage of 450 / 750V and below, fixed laying of electrical power devices and power transmission and distribution system with rated AC voltage of 1kV and below for power transmission and distribution. Widely used in electric power, construction, mining, metallurgy, petrochemical, transportation and other departments. In good use environment, it can be used continuously in the range of rated voltage and current grade, and its service life is consistent with that of copper cable.
    Product features
    1) It has good corrosion resistance and low contact resistance. Under normal conditions, aluminum is easier to corrode than copper, but because the aluminum of copper-clad aluminum is completely covered by copper, the weakness of aluminum conductor such as easy oxidation and high contact resistance is improved.
    2) it has good solderability. Copper clad aluminum wire has the same solderability as pure copper wire because its surface is covered with a layer of pure copper. It can avoid the hidden danger that the aluminum core cable will be burnt due to corrosion, bumping, poor compression and Wuxi welding.
    3) light weight, soft thread, easy processing, easy installation and transportation.
    4) the copper-clad aluminum material has the advantages of relatively low cost and relatively stable price, which overcomes the disadvantages of high cost and high price of copper.
    5) Compared with pure copper conductor, copper-clad aluminum conductor has the advantages of pure copper conductor. Under the condition that the DC resistance of conductor is the same as that of pure copper conductor (the cross-sectional area is larger than that of pure copper), its AC resistance is smaller than that of copper conductor, and its current carrying capacity is 2% - 5% larger than that of copper conductor (the larger the cross-sectional area is, the more obvious the effect is). The technical indexes such as line loss, temperature rise and high-order harmonics of the cable are better than those of copper conductor cable. When connected with the same copper terminal, the temperature rise at the joint is lower than that of copper.