Introduction of Different Bonding Method to Self Bonding Enameled Wires
1, Introduction to Self Bonding Enameled Wires
Self bonding enameled copper round wires, self bonding enameled copper clad aluminum round wires and self bonding enameled aluminum round wires are enameled wires formed by evenly coating the insulating film and self bonding film on the metal conductor and baking.
The insulation film mainly includes polyurethane, polyester, polyester-imide, polyamide-imide, polyimide, etc., with temperature resistance of 130-240 class. According to the market demand, various enameled wire products with double insulating films compounded by two kinds of insulating primers have also been developed.
There are two types of self bonding paint films: thermoplastic and thermosetting.
2, Bonding Method
● Solvent Self-adhesive
Solvent self-adhesive is to achieve the effect of self bonding by coating appropriate solvent (ethanol) on the wire through the device in the process of winding. The solvent concentration of 80% - 90% is preferred, and the solvent can be diluted with water. If the concentration is too low, the self bonding process will become difficult.
● Oven Self-adhesive
Oven self-adhesive is to put the self bonding coils into the oven for heating to achieve the curing effect of the self bonding film and further improve the re-softening temperature. In order to achieve uniform heating of the coils, the temperature of the oven usually needs to be between 170 - 230 centigrade according to the shape and size of the coils, and the time required is 20 to 40 minutes.
● Hot Air Self-adhesive
Hot air self-adhesive is to achieve the purpose of self bonding by blowing hot air to the wires in the process of winding. The temperature of hot air at the winding is usually between 170 to 230 centigrade, which depends on the wires’ diameter, winding speed and the shape and size of the winding. This method is suitable for most applications.
● Energized Self-adhesive
Electrified self-adhesive is that the coils are heated by current and the self bonding film melts to realize self-adhesive. The required current intensity depends on the shape and size of the coils. Energized self-adhesive is recommended for wires above 0.10 mm (AWG 38), but special attention should be paid not to overheat the center of the winding, because too high temperature may damage the insulation and cause short circuit.