Best corrosion protection thanks to zinc-magnesium

• Excellent corrosion protection
• Excellent edge protection
• Improved production conditions
• Product in terms of sustainability
• Shorter supply chain and improved cost effectiveness
• Certified via EN 10346

Wuppermann's WTopCor zinc-magnesium coating is distinguished from conventional protection methods by the fact that the process has improved product properties compared to steel strip with zinc coatings. The advantages become particularly clear in the so-called salt spray test.

Rounding off refers to the machine processing of the longitudinal edges of longitudinally split, galvanised steel strip. The galvanised slit strip is continuously fed through the machine with appropriately positioned steel rollers. In the process, the sometimes sharp cut edges are formed. The zinc or zinc-magnesium coating in the edge zone is also plastically deformed during this process and virtually flows over the edge. This allows the corrosion protection to be extended beyond the edges and the so-called cathodic edge protection to be strengthened or, in the case of thicker slit strips, to be brought about.

The WTopCor coating even ranks ahead of zinc in the electrochemical voltage series. The melt solidified in equilibrium (eutectic) therefore has a higher normal potential than zinc and is therefore even more active and effective in corrosion protection than the zinc coating. Zinc "sacrifices" itself as a less noble metal and protects the steel against red rust formation through an electrochemical active process during natural weathering.

It is almost impossible for the environment to penetrate the WTopCor coating.

The WTopCor alloy convinces with better friction, wear and sliding properties. In press shops and profiling plants, this results in savings in energy and material use, production and maintenance. At the same time, occupational safety is improved.

Advantages in brief:

• Good forming properties due to lower coefficients of friction à The thin metallic WTopCor coating adheres perfectly to the steel strip, which thus also allows complex deformations.
• Lower drive power of the machine motors
• Minimal tool wear
• Longer maintenance intervals of the machines
• Lower noise level during production
• Less contamination of the production tools and machines

Wuppermann understands sustainability as a form of ecological and economic action that ensures comparable or better living conditions for present and future generations. WTopCor-treated steels are 100% recyclable, they do not contain any harmful substances and are compliant with the European "REACH" and "ROHS" directives. In addition, the so-called wash-off rate, i.e. the removal of a WTopCor coating by rainwater into the soil, is considerably lower than with a zinc coating. One of the most significant advantages is the halving of the layer thickness compared to a zinc coating. The halving is feasible due to the improved corrosion resistance.

The simple production process shortens the delivery time. At the same time, WTopCor is cost-effective compared to stainless steel and aluminium. Repainting is not necessary with WTopCor, so maintenance costs are also reduced.

Technologically, a distinction is made between the batch galvanizing process and the continuous strip galvanizing process. To put it simply, in the traditional piece galvanising process, already formed components are dipped into a zinc bath, whereas in the continuous process, the zinc is applied to the still flat strip steel and the shaping into the profile only takes place after the galvanizing process. The continuous process has several advantages.

The zinc layer is applied to the preheated steel strip within a few moments. The zinc layer thickness can be adjusted continuously from 50 g/m² to 1200 g/m² using so-called "air knives" and is independent of the thickness of the steel strip. This means that even very thin steel can be provided with very high zinc coating thicknesses and can be used in particularly harsh environmental conditions.

Coating weights of up to 1,000 g/m2 give WTopCor coated, cold-formed products a theoretical protection period of over 50 years. For WTopCor1000, the German Institute for Building Technology (DIBt) has granted building authority approval for corrosivity category C5-H. Meanwhile, Wuppermann Austria GmbH in Judenburg is already producing WTopCor1200.