In a sense, the enameled wire manufacturing industry is a material finishing and assembly industry. First, the amount of materials is huge, the cost of materials in cable products accounts for 80-90% of the total cost of manufacturing; second, the types and varieties of materials used are very high, and the performance requirements are particularly high. For example, copper for conductors requires copper purity. Above 99.95%, some products use oxygen-free high-purity copper; third, the choice of materials will have a decisive impact on the manufacturing process, product performance and service life. Among them, the selection of copper enameled wire is especially important, and if it is slightly inadvertent, it may cause a safety accident. Below, I will sort out the reasons and treatment methods for the yellowing of copper enameled wire.
There are several reasons why Varnish Wire is yellowed:
1. The temperature of the tin furnace is too high, and the fluidity is large, which leads to excessive pinhole penetration and fast penetration of copper and tin.
2 the tin layer is too thin, copper and tin penetrate quickly
3 too much flux halogen residue, copper surface pickling is not thorough enough
4, the packaging time is too fast, the heat is not scattered, the tin furnace impurities
5. The quality of copper is not enough, too much impurities
6. The temperature level has an effect on the activity of copper atoms, and the hot days are faster than the cold days.
These problems can be solved by the following treatments:
1. Mold hole diameter > line pass +0.02mm (the purpose is very simple, the plating layer is too thin);
2. After the production, put it for about 2 hours and then repack it (purpose: internal heat dissipation);
3. Purchase a good flux, with a good flux concentration, mainly the flux affects the tin plating quality;
4. Pick a better oxygen-free copper wire.