Chemical coppering of wires for tires and welding: the solution

In the automotive industry the classic carbon steel wire was replaced around the 80s with copperized wire, exponentially improving the resistance and performance of the tire itself; the copper layer binds to the special rubber of the tire consolidating the overall structure of the finished product. In the welding market the copper wire must have, besides the conductivity characteristics, a shiny aesthetic appearance.

Currently for the preparation of the coppering solution, copper sulfate water and concentrated sulfuric acid are solubilized in water, leading to many inconveniences such as, for instance, superficial roughness increase, micro-crystalline embrittlement phenomena(causing physical properties variations) and iron increase in the solution limiting the duration of the coppering solution.

For this purpose Condoroil has developed CUPROCOND 67 L, a product with addition of corrosion inhibitors which slow down the parasitic acid dissolution process, and eliminate the problems of mixing the two components (thus improving safety for operators in the workplace). In order to optimize the process, and therefore the final result, in the formulation of CUPROCOND 67 L, inert surfactants have also been included, which allow to have an uniform adhesion reaction of copper, and antioxidant agents which limit the oxidation, due to atmospheric agents, towards the obtained copper layer. The solution of CUPROCOND 67 L must be simply added to water and heated to working temperature (40 °C) and then corrected with sulfuric acid, up to the free acidity required by the specific line. The obtained copper layer is relative and proportional to the surface to which the chemical adhesion will occur: smoother and cleaner is the surface to be coppered and better will be the resulting layer in terms of uniformity. Finally, we highlight the possibility, with the use of the technologies to minimize waste proposed by Condoroil Stainless, to recover from the spent solution, by-products having a certain commercial value such as metal copper, sulfuric acid and ferrous sulfate and, moreover, to reduce the costs of waste water treatment and disposal of the sludge generated during the purification itself.

Condoroil awaits you at the international trade show wire & Tube Düsseldorf 2018, from 16 to 20 April, to present you all the latest novelties for the wire industry (stand 10 B48).