Understand The Performance Characteristics Of Aluminum Magnet W


    Magnet wire is one of the main raw materials for motors. The wire used for windings or coils is called enameled wire. There are many types of electromagnetic wires, which can be divided into round wires, flat wires and strip wires according to their cross-sectional shape. The cross-sections of round wires and flat wires have a uniform standard size. The cross-sectional size of the strip conductor is based on the design requirements and can be ordered by the wire manufacturer. According to the characteristics and uses of the insulating layer, enameled wires can be divided into four categories: enameled wires, covered wires, inorganic insulated wires and special enameled wires


    1.aluminium Magnet wire

    The enameled wire requires the paint film to be uniform, smooth and completely covered (the number of pinholes is small). The wire diameter and paint film thickness should comply with national standards. The performance of the enameled wire is determined by the paint film, and generally includes the following items:

    (1) Mechanical properties. The paint film should be scratch-resistant, elastic, and have appropriate flexibility and elongation to ensure that the paint film can withstand friction, bending, stretching and compression during the winding, embedding, stretching, and shaping process. Will not cause damage.

    (2) Electrical performance. The main reason is that the breakdown voltage of the paint film is higher. The enameled wire used for high-frequency and high-voltage motor windings requires a small loss tangent of the paint film. For enameled wires with a diameter of less than 0.5, the number of pinholes is a very important indicator to evaluate its electrical performance; many motor manufacturers are equipped with paint film continuity testers to check the number of pinholes when inspecting magnet wires in the factory.

    (3) Thermal performance. Including the softening breakdown, thermal aging and thermal shock properties of the paint film. The softening and breakdown performance indicates the ability of the paint film to resist thermal deformation under a certain pressure; the thermal aging performance reflects the ability of the paint film to maintain a certain degree of elasticity after being heated for a short time; the thermal shock performance reflects the baking and impregnation ability of the paint film The ability of the film to withstand thermal shock (rapid cold, heat) without cracking during processing or overload operation.

    (4) Chemical properties. Indicates the ability of the paint film to resist the corrosion of chemicals such as acid, alkali, salt spray, organic solvents or refrigerants.CCA wire

    2. Winding

    At present, the commonly used motor winding covered wires mainly include glass fiber covered wires and film covered wires. Glass fiber covered wire is made by tightly winding alkali-free glass wire on bare wire or enameled wire, impregnating it with insulating varnish, and baking it. The electrical and mechanical properties of glass fiber covered wires are better than enameled wires, and the heat resistance grade depends on the heat resistance of the bonded insulating varnish and enameled wires.

    For glass fiber-coated wires, except for dimensional tolerances that do not exceed regulations, when the flat wire is bent at 180° on the wide side, the insulation layer shall not fall off, crack, expose copper or paint, and shall not break the fiber; insulation resistance and breakdown voltage.

    Film wrapping wire has high mechanical and electrical properties and is a very valuable wrapping wire. At present, there are glass fiber wound polyester film winding wire and polyimide film winding wire. Polyimide film covered wire can withstand high temperature, low temperature, and radiation; it has good air tightness, electrothermal aging performance and drag resistance; the slot space utilization rate is higher than that of glass fiber. Glass fiber covered polyester film covered wire has good electrical and mechanical properties, but the insulation layer is thicker.

    3. Inorganic insulated wires

    Inorganic insulated wires for motor windings mainly include oxide film aluminum wires. It uses anodizing method to generate a dense aluminum oxide film on the surface of the aluminum wire. It has the advantages of thin insulating layer, good heat resistance, and radiation resistance; but the oxide film is porous, so the breakdown voltage is low; at the same time, its bending resistance, scratch resistance, acid resistance and alkali resistance are poor.

    4. Special enameled wire

    Special enameled wire has insulation structure and performance suitable for special environment. For example, PVC insulated enameled wire and polyethylene insulated nylon sheathed enameled wire used for submersible motor windings. The former has better water resistance, but the slot space utilization is low; the insulation layer is easily damaged when the coil is wound, and is used for general submersible motors. The latter has good water resistance, high mechanical strength of the sheath, but low slot space utilization, and is often used in water-filled submersible motors.