Introduction to de-enameled and tinned coils

The de-enameled and tin-coated coil is a type of coil that undergoes special treatment on the ends of enameled wire coils. The core is to achieve fast and reliable circuit connection by removing the insulating varnish layer at the coil lead-out end and covering it with a tin layer. It is widely used in electronic components that require soldering and assembly.

I. Basic Structure and Key Processing Points

The main body of the coil is wound with enameled copper wire (or silver wire). The insulating varnish layer on the surface of the wire ensures insulation between the windings. The winding shape can be designed as circular, square, etc. according to requirements, and some are equipped with an insulating skeleton fixed structure.

The core of the end treatment: The lead-out wires at both ends of the coil need to go through two key processing steps - first, the local insulating varnish layer is removed by mechanical scraping, chemical paint remover dissolution or laser vaporization, etc., to expose the clean metal conductor; Then, immerse the de-painted end into the molten tin bath or solder it with a laser to ensure that the tin layer adheres evenly to the surface of the conductor.

Key points of processing control: The length of paint removal needs to be precisely controlled. If it is too short, it may lead to poor tin application; if it is too long, it may cause short circuits in adjacent pins. When applying tin, it is necessary to ensure that the tin layer is full and free of pores to avoid the risk of false soldering.

Ii. Core Features

High connection efficiency: The pre-made tinned ends can be directly soldered to the PCB board and terminal blocks without on-site paint layer treatment, greatly simplifying the assembly process and especially suitable for mass production scenarios.

Strong electrical stability: The tin layer can reduce contact resistance and prevent oxidation at the ends of the wire, avoiding poor contact during long-term use and enhancing the reliability of circuit conduction.

Compatible with multiple processing methods: It can be used not only with traditional soldering iron welding and tin bath immersion processes, but also with precision processing technologies such as laser soldering, meeting scenarios with different precision requirements.

Iii. Main Uses

In the field of electronic components: As winding coils for inductors, small transformers, and relays, they are easily soldered to circuit boards after being tinned at the ends. They are commonly used components in power filters and control boards of household appliances.

Motors and precision equipment: Micro motors and small coils in automotive electronics achieve reliable connection with controllers through end paint stripping and tin coating, meeting the requirements of high-frequency operation.

Communication and consumer electronics: The micro-coils inside optical modules and the windings of electro-acoustic devices such as headphones ensure stable signal transmission and enhance equipment performance through precise paint stripping and tin coating processes.

Iv. Differences from Ordinary Coils

The end treatment is different: For ordinary enameled wire coils, the insulating varnish layer is retained at the lead-out end, and additional varnish removal is required before welding. The de-enameled and tinned coils have completed end treatment before leaving the factory and can be directly assembled.

Connection reliability difference: The on-site paint removal of ordinary coils is prone to poor soldering due to incomplete treatment. The paint removal and tinning coils, through standardized processes, ensure the quality of the ends and have better connection stability.

The applicable scenarios are different: Ordinary coils are suitable for manual assembly or scenarios that do not require soldering, while de-painted and tinned coils are specifically designed for mass production scenarios involving automated soldering and precise connections.