Anti corrosion coating for steel protection in any environemnt
Anti corrosion coating acts as a barrier between a metal and its environment, increasing its durability and lifespan. The estimated global cost of metal corrosion damage is billions of wons. The good news is, a lot of this loss can be prevented by being proactive, and choosing the right anti corrosion coating from the start.
To determine the right anti corrosion coating for your project, it is important to factor in the environment and type of metal. Whether corrosion is due to moisture, chemicals, salt spray, or oxidation, anti rust coating for steel and metal can help protect the substrate from the elements.
In this article we will guide you through the corrosion categories per environment, outline suitable products per category and introduce the anti corrosion coating companies in Korea.
The corrosivity of the environment defines the needed anti rust paint
To determine the right types of anti corrosive paints for your project, you need to understand the environment and use of the substrate. Particularly its exposure to water, moisture, and other aggressive substances that might be present in the environment. The corrosivity of certain atmospheres has been classified and standardised by the International Organisation for Standardization. The standard divides the degree of corrosivity into 5 categories , C1 to C5, in order of increasing corrosivity. To find the right anti corrosion coating, you need to know how corrosive the environment will be. For example, a coating at C5M level is intended for offshore constructions which are constantly exposed to moisture, but also for small pipes that are equally exposed.
|Corrosion Category||Suitable for||Examples|
|C1 – very low corrosion risk||Heated buildings with clean air, interiors only||Offices, schools, hotels, shops and other heated premises|
|C2 – low corrosion risk||Unheated buildings, rural areas||Storage facilities, sports halls, garages, barns and other unheated buildings|
|C3 – moderate corrosion risk||Buildings with high humidity, urban and industrial areas||Laundries, breweries, kitchens, food processing sites and other buildings with moderate humidity|
|C4 – high corrosion risk||Chemical manufacturers and swimming baths, industrial and coastal areas||Industrial buildings, chemical plants, swimming pools, ports, and ship- and boat yards|
|C5 – very high corrosion risk||Buildings with almost permanent condensation, offshore and industrial areas||Water pipes and other industrial applications (C5I – industrial). Offshore and maritime constructions (C5M – marine)|
Once you have identified your environment, you can identify the right anti rust treatment for your project and the right anti rust coating specification to protect it for years to come. Following these guidelines will allow you to pick appropriate anti-corrosion coatings, allowing you to avoid overspending on unnecessary degrees of protection or simply making the wrong choice.
Choose an anti corrosive coating that matches the category
Anti corrosion coating types can be divided into three categories:
- Galvanic coatings/Cathodic protection (C3 – C5) – metal-rich anti rust coating for steel which provide a sacrificial layer. Prevents corrosion by providing a more easily corroded metal (such as zinc) to be the anode to the protected metal’s cathode. Also called the sacrificial anode, this metal will corrode instead of the protected metal.
- Barrier coatings (C1 – C3) – non-porous anti rust coatings designed to prevent corrosive factors coming into contact with the substrate.
- Inhibitor coatings (C1 – C4) – anti rust treatment which releases a chemical that interferes with the electrolyte and stops the corrosion process.
Spray and dip applications
The two most common methods for applying a industrial grade metal anti corrosion coating are hot dip galvanisation and thermal (metal) spraying:
- Thermal (metal) spraying applies zinc or aluminium to a substrate by taking the metal in the form of a powder or wire and feeding it into a special spray gun. The metal is melted within the gun and can then be sprayed onto the substrate. It does not alloy, but instead works by coating the surface in overlapping metal platelets.
- Hot Dipping is the process of immersing a metal in a bath of metal, often molten zinc, in order to form a coating. The liquid metal bonds to the substrate and forms an alloy, which is then coated in zinc as it is removed from the bath. Hot dip galvanising uses the principle of cathodic protection, as the zinc coating acts as an anode to its substrate.
Excellent protection with duplex system anti corrosion coatings
When hot dip galvanising is used together with a topcoat of anti corrosion paint or powder it is known as a Duplex System. The duplex systems are applied as anti rust coating for steel and occasionally other metals.
This type of anti rust treatment provides multiple types of protection and the longest-lasting results. Each layer needs to be compatible in order for the system to work effectively. Duplex anti rust coating systems are especially suitable for corrosion categories C3 to C5, and it looks like this:
- Surface preparation: derusting, blasting, removing grease, oil, dirt for optimum adherence.
- Hot dip galvanisation OR applying an inhibitor coating primer depending on the coating system of your choice.
- Applying a sealer: To seal the anti corrosion coating. Often epoxy based.
- Intermediate coat: several layers may be necessary for optimum protection, depending on the corrosion category and the chosen anti rust paint.
- Finishing coat: provides appearance and surface resistance, often first line of defence.
Treating small surfaces against corrosion – anti rust spray & paint
For smaller substrates or do it yourself application up to category C2, painting is also an option. There are also small anti corrosion spray paint cans available for this purpose. An anti corrosion coating spray can be described as an ultra thin fluid film compound which you can spray on any steel or metal surface. In spray form it can protect for up to a year. But keep in mind that more exposed areas that are getting constant abuse from rain and salt will need spraying regularly. With anti rust paint, more long lasting results can be accomplished depending on the coating system you choose. For the best result always opt for a two component anti rust coating with corrosion inhibitor additives, for example a zinc rich epoxy coating.
Anti corrosion coating manufacturers in Korea
Anti corrosion coating is a common product which also belongs to the portfolios of most multinational coating manufacturers. Here below you can find a list of those also having business units in Korea.
|Anti corrosion coating manufacturer||Address (South Korea)|
|AkzoNobel Pacific Korea||402Ho, 4th Floor, 987-5, Singa-dong, Gwangsan-gu N/A , 506-307 Gwangju|
|PPG Korea Ltd.||128-7 Yongdang-Dong , Busan, Busan 608-829 , Korea (Republic of)”|
|Hempel(Korea)Co.LTD.||5th floor, SK Global bldg,, Jobang-ro 16 beon-gil 5,, Dong-gu, Busan|
|BASF||39 Sejong-daero, Namdaemunno 4(sa)-ga, Jung-gu, Seoul, South Korea|
|Sika Korea Ltd.||16, Nonhyeon-ro 135-gil, Gangnam-gu, Seoul 06041|
Professional application is the key to a successful anti rust coating
Keep in mind that for categories C4 and C5 it is not recommended to apply the anti corrosions coating yourself. Please search out a specialist in that case.
If you are looking for a professional company to apply the anti corrosion coating for you, it’s important to understand how prices are established before you request a quote. Different coating processes use different methods to calculate the cost of professional application. Hot dip galvanising prices are usually calculated by weight. The galvaniser will quote a price per tonne, and then use the weight of your steelwork after galvanising to calculate the final cost. Unlike galvanising, powder coating prices tend to be calculated by size or surface area.
Regional differences in materials, labour, and equipment can all have an impact on overall costs when contracting an anti rust coating expert. If you want to receive a custom made quote, please contact us.