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Professional surface pretreatment
for long-lasting component quality

The quality of the bonding between rubber and metal or plastic is crucial for the performance and lifetime of the final product. For optimum results and a long-lasting bond, it is necessary to fully clean, activate and individually pretreat the surface before applying the bonding agent, because residues or impurities reduce the adhesion of the following coating and have a negative impact on the overall quality. Based on our decades of experience and our high quality standards, we know that it is essential to match the type of pre-treatment to the base material, the condition and degree of pollution on delivery and to the requirements of the end product. Because this creates the essential preconditions for the following coating process.

Surface cleaning

The first step is usually a deep cleaning of the raw parts in order to completely remove, for example, grease and oil residues that have arisen during production. Which process is most suitable depends, among other things, on the material and the extent of the contamination. Common methods include degreasing with perchloric steam and alkaline cleaning.

Degreasing with perchloric steam

In this process, a special type of solvent is heated until it reaches the boiling point and vaporises. The hot solvent steam condenses on the substrate surface, dissolves the grease and rinses them off almost without leaving any residue. This process is particularly suitable for sensitive raw parts and enables the highest degree of purity in our degreasing processes. In addition, the process of degreasing with perchlorine steam is considered safe and low-emission because it is a closed system and thus no solvents are released into the atmosphere.

Alkaline cleaning

In this process, the parts are cleaned in a hot water solution and partly under very high pressure. The high temperatures cause the grease to "saponify" and the water can dissolve the grease from the surface in this way.

Blasting

Pretreatment by blasting is used to clean, enlarge and roughen the surface of metals and plastics. Impurities are removed and the surface roughened by the solid abrasive hitting at high speed (approx. 80 m/s). While the parts are in the blast machine, they are constantly circulated so that all surfaces are treated evenly. The surface roughness created by blasting is a prerequisite for further coating processes. The blasting media are matched to the application; for example, corundum, steel gravel or stainless steel gravel are used.

Phosphating

Phosphating is a pretreatment process in which a conversion layer is created on metallic surfaces through chemical reactions. The process often takes place in rotating drums with bulk material and is used for corrosion - but also for infiltration protection and adhesion. There are different methods of phosphating: ZnCa-Phos, ZN-Phos anda FE-Phos.

Zinc-nickel coating

The galvanic zinc-nickel (Zn-Ni) process is characterised by very good corrosion protection and is preferably used in the automotive industry for components with high corrosion requirements in the engine compartment, chassis or on brakes. The basis for a high-quality zinc-nickel coating is chemical cleaning by degreasing, pickling and activation of the surface. This is followed by the electrolytic zinc-nickel coating process in rack or barrel systems, before post-treatment, passivation or sealing including drying form the final step.

Special processes

The Bonderite process enables complete coating of cavities, edges and the smallest gaps, as it works on a chemical basis and thus no "Faraday effect" occurs. In addition, the low coating temperature ensures complete form stability.
Satin finishing creates an even, matt surface. The multi-stage sanding process creates a so-called "line pattern" without changing the geometric shape of the workpiece.

Surface activation

The next step in pretreatment is the activation of the surface in preparation for further coating processes. A distinction is made between layer-forming (phosphating, zinc-nickel, bonderite) and non-layer-forming processes (blasting, calendering). Both processes structure the surface and roughen it.

GOTEC - Experienced specialist for pretreatment
according to highest quality standards

The requirements for surfaces are diverse. Depending on the area of application and the base material, various pretreatments may be necessary. Based on decades of experience, we can draw on in-depth know-how and understand the requirements of many applications and industries. Standardized processes, state-of-the-art technologies and the high degree of automation allow us to offer the highest quality at the best price-performance ratio.

Perfomance

Deep cleaning and activation of the surface is essential for the performance of the final product.

Quality

Only professional pretreatment guarantees a long-lasting bond between rubber and metal/plastic.

Sustainability

We use the most environmentally friendly products and processes with low energy consumption.