Today, let's introduce to you what the early Enameled Wire looked like. And its slow evolution.
Early use of cotton yarn and silk, known as yarn and silk wrap, was used in electrical machines and appliances. Due to the large insulation thickness and low heat resistance, most of them have been replaced by enameled wire, and the paper wrapping wire still occupies a considerable position in the wrapping wire, which is mainly used in oil-immersed transformers.
1. The earliest enameled wire was oily enameled wire, made of tung oil, etc. Its paint film has poor abrasion resistance and cannot be directly used for manufacturing motor coils and windings. When in use, a cotton yarn wrapping layer should be added.
2. The polyvinyl formal enameled wire was invented later. Its mechanical properties were greatly improved. It can be directly used in motor windings and is called high-strength enameled wire.
3. With the development of weak current technology, self-adhesive enameled wire has appeared again, and coils with better integrity can be obtained without impregnation and baking.
4. Due to the increasingly wide application of enameled wire and the increasingly strict requirements, composite enameled wire, such as polyamide-imide enameled wire, have also been developed.