The (copper) coat must come off

Selective soldering processes allow coated enamelled copper wires to be thermally stripped and soldered in a single step without having to remove the insulation.
Specific process knowledge forms the core know-how of lead-free processing of characteristic solder alloys. High-temperature soldering modules have been developed that can be used at temperatures of up to 480 °C and work reliably with static or flowing solder melt. In order to achieve a high tin-plating quality of the enamelled copper wires, despite copper alloys or leaching, stripping is defined in a process-friendly and product-specific manner via the static or flowing solder melt and the exact temperature time curve. In addition, solders with additional alloys counteract various negative effects. For example, by reducing wire alloying, solder oxide formation and solder contamination and protecting the soldering system.
The high-temperature process for tinning can be carried out with both a static solder bath and a dynamic, freely programmable doctor blade system. In this way, contamination can be reduced and the base alloy of the solder can be maintained in its original composition throughout the entire process. The controlled removal of contaminated solder and the automatic refilling of base solder remains constant throughout the entire production process. The wire ends can be moved kinematically in both the static and the flowing solder wave during the exchange movement and, if necessary, separated with appropriate masking, which enables a clean lacquer demarcation between the tinned wire and the poly-insulation.
The surfaces that come into contact with hot solder are protected by special coatings. This applies to both static and flowing solder melt. Furthermore, an induction solder pump was developed for this application, which is free of moving parts.