Classification of corrosion protection methods (Part 2) - Protective Coating Method

 Protective coating method


The protective coating method is a passive corrosion protection method. The protective coating isolates the metallic surfaces from the aggressive media, such as moisture, salts, acids etc..

The following corrosion protection agents are used:

	Solvent-based anticorrosion agents Very high quality protective films are obtained. Once the anticorrosion agent has been applied, the solvent must vaporize so that the necessary protective film is formed. Depending upon the nature of the solvent and film thickness, this drying process may take as long as several hours. The thicker the film, the longer the drying time. If the drying process is artificially accelerated, there may be problems with adhesion between the protective film and the metal surface. Since protective films are very thin and soft, attention must always be paid to the dropping point as there is a risk at elevated temperatures that the protective film will run off, especially from vertical surfaces. Since solvent-based corrosion protection agents are often highly flammable, they may only be used in closed systems for reasons of occupational safety.
	Water-based anticorrosion agents Water-based anticorrosion agents contain no solvents and thus do not require closed systems. Drying times are shorter than for solvent-based anticorrosion agents. Due to their elevated water content, water-based anticorrosion agents are highly temperature-dependent (risk of freezing or increased viscosity). The advantage of this method is that the protective film is readily removed, but the elevated water content, which may increase relative humidity in packaging areas, is disadvantageous.
	Corrosion-protective oils without solvent Corrosion-protective oils without solvent produce only poor quality protective films. Good quality protection is achieved by adding inhibitors. Since these corrosion-protective oils are frequently high quality lubricating oils, they are primarily used for providing corrosion protection in closed systems (engines etc.).
	Dipping waxes The protective layer is applied by dipping the item to be packaged into hot wax. Depending upon the type of wax, the temperature may have to be in excess of 100°C. Removal of the protective film is relatively simple as no solid bond is formed between the wax and metal surface. Since application of dipping waxes is relatively complex, its use is limited to a few isolated applications. http://www.tis-gdv.de/tis_e/verpack/korrosio/schutz/schutz.htm Leopad Group a leading provider of corrosion protection services ranges from the scope of blasting and painting, insulation, thermal spray application, passive fire protection, refractory and other services such as scaffolding, cable tray systems and cathode protection. We are a Malaysian company with close to 3000 staff and over 10 offices and fabrication yards throughout the country. Leopad Group is dedicated to being the market leader for corrosion protection and provide the highest standards in the industry with the convenience of providing multi-disciplinary services through a single point of contact. For further enquiries on our services, please contact our Business Development Department at +603-22600200 , website www.leopad.com or email at hq@leopad.com