The state-of-the-art manufacturing process for enameled wire involves the application of liquid enamel (varnish) to the drawn conductive material. First, the wire is drawn to the desired conductor size. After drawing, the wire is annealed to restore mechanical properties for further processing. The enameling process consists of enameling, curing and cooling.

First, the bare annealed conductor is passed through a bath with liquid enamel. Due to its high viscosity, a thick film is formed on the wire. Afterwards, the wire passes through an enameled mold with a specified cross-section.

The gap between the conductor and the mold increases the enamel with each passage. Subsequently, the wire passes through a curing oven which, at a temperature of approx. 600 °C, evaporates the organic solvent from the liquid enamel and forms a dense solid insulating layer. After the wire has cooled, the process is repeated until the desired insulation thickness is achieved. Before the coated wire is wound onto a spool, the wire is tested for surface defects and insulation discontinuities on a per-inch production basis using in-line measuring equipment.


Depending on the type of material, diameter, and thickness of the enamel cross-section, vertical (built-in tower approximately 30m high) and horizontal wires are used. Although the fundamentals of the recycling application and subsequent curing of liquid enamel have remained unchanged for decades, modern machines are more efficient, more productive and significantly more environmentally friendly, and they are fully integrated into the industrial infrastructure. 21st Century.

The first industrially available alternative to enameled copper wire appears to be extruded PEEK enameled wire. Here the conductor is covered with a layer of high-performance polymer (in this case PEEK - polyether ether ketone). 

Although these wires have not yet been standardized and they have only been on the market for a few years, they are already being used in some rare high-performance applications. Their popularity due to their excellent chemical and mechanical resistance, combined with the high applicable thicknesses and virtually defect-free surfaces, are good prerequisites for high-performance applications. On the other hand, optimized enameled wires are already comparable to extruded wires. Last but not least, in order to realize relatively small performance advances, a significantly higher price has to be paid (the price factor is about 3 - 5 times higher than for enameled wires).