Enameled wire is a category of electromagnetic wire, generally refers to the insulated wire used to make coils or windings in electrical products. Also called winding wire.
The electromagnetic wire must meet the requirements of various applications and production processes. The former includes its shape, specifications, ability to operate at high temperatures for short and long periods, as well as acceptance of intense vibration and centrifugal force at high speeds on some occasions, resistance to corona, and breakdown under high voltage, and resistance to special atmospheres. Chemical corrosion, etc.; the latter includes requirements for stretching, bending, and abrasion during winding and embedding, as well as swelling and erosion during dipping and drying.
Magnetic wire can be classified according to its basic composition, conductive core, and electrical insulation layer. Generally, it is divided into enameled wire, winding wire, enameled winding wire, and inorganic insulated wire according to the insulating material and production method used for the electrical insulation layer.
The conductor is coated with a corresponding paint solution, and then the solvent is volatilized and the paint film is solidified and cooled. Enameled wire can be divided into polyester enameled wire, polyester imide enameled wire, polyamide-imide enameled wire, polyimide enameled wire, polyesterimide/polyamide-imide enameled wire, corona resistant enameled wire, and oily enameled wire according to the insulating varnish used. Paint, acetal paint, polyurethane enameled wire, etc. Sometimes it is also classified according to the particularity of its use, such as self-adhesive enameled wire, refrigerant-resistant enameled wire, etc.
The earliest enameled wire is oily enameled wire, made of tung oil. The paint film has poor abrasion resistance and cannot be directly used to make motor coils and windings. It needs to be used with a cotton yarn wrapping layer. Later, the polyvinyl formal enameled wire came out, and its mechanical properties were greatly improved, and it can be directly used in motor windings, which is called high-strength enameled wire.
With the development of weak current technology, it has also presented a self-adhesive enameled wire, which can obtain a coil with better integrity without dipping and baking. But its mechanical strength is poor, and it can only be used in micro motors and small motors. In addition, to prevent the trouble of removing the paint film first during soldering, direct solder enameled wire has been developed, the paint film of which can fall by itself in the high-temperature tin enamel tank, making the copper wire easy to solder.