Corrosion resistant paint for steel for optimal protection from rust
Corrosion resistant paint forms a barrier between a metal and its environment, and increases the metal’s durability and lifespan. The roughly estimated global cost of metal corrosion damage is trillions of dirhams. The good news is, that a lot of this loss can be prevented by being proactive, and making the right choice of corrosion resistant paint at the start. To determine the best 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, corrosion resistant coating for steel and metal can help protect the substrate from the elements.
In this article we provide an overview of the conditions that cause rust and the anti corrosion measures needed to combat it, as well as the best anti corrosion coating systems. We also take a look at anti rust coating supplier and anti rust coating manufacturer landscape in the UAE.
Use anti corrosion paint to meet the requirements of the corrosion category
To determine the best anti rust coating 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 standardized by the International Organization for Standardization. The standard divides the degree of corrosivity into 5 categories , C1 to C5, in order of increasing corrosivity. To find the right corrosion resistant coating or paint, 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.
- C1 – very low corrosion risk: Heated buildings with clean air, interiors only.
Suitable for: offices, schools, hotels, shops and other heated premises.
- C2 – low corrosion risk: Unheated buildings, rural areas.
Suitable for: storage facilities, sports halls, garages, barns and other unheated buildings.
- C3 – moderate corrosion risk: Buildings with high humidity, urban and industrial areas.
Suitable for: 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.
Suitable for: industrial buildings, chemical plants, swimming pools, ports, and ship- and boatyards.
- C5 – very high corrosion risk: Buildings with almost permanent condensation, offshore and industrial areas.
Suitable for: Water pipes and other industrial applications (C5I – industrial). Offshore and maritime constructions (C5M – marine).
Once you have determined the corrosivity of your environment, you can identify the right anti corrosion coating systems for your project and the right corrosion resistant coating specification to protect it for years to come. Following these guidelines will allow you to pick appropriate corrosion protection paint, allowing you to avoid overspending on unnecessary degrees of protection or simply making the wrong choice.
Corrosion resistant paint is not a single type of coating
Corrosion protection coatings is essentially a collective name for various types of coatings that protect a substrate from corrosion. Corrosion resistant paint can do more than just protect from corrosion, and its multi-functional nature means that it is possible to find the exact coating you require. Corrosion is caused by a chemical reaction between a metal and its environment (water or other fluids), typically producing an oxide or a salt of the original metal. The long and the short of it is the metal is weakened, as is the structure it creates. An anti corrosion coating prevents direct contact between water/fluids and the steel substrate and therefore prevents the corrosion process.
In general corrosion protection coatings are suitable for almost any type of steel and metal, and have the following 5 benefits:
- Weather protection against acid rain, salt water, ice and so on
- Chemical resistance
- Repels water & other fluids (in case of barrier coatings)
- Fends off fungi, algae, and moss
- Plus, depending on the type of anti-corrosion coating you opt for: anti fouling, non slip or self cleaning properties
3 types of corrosion protection paint for industrial use
Corrosion resistant paint can be divided into three categories:
- Barrier coatings (C1 – C3) – non-porous steel corrosion protection coatings designed to prevent corrosive factors coming into contact with the substrate.
For example: powder coating, polyurethane paint, chloro-rubber paints, Teflon coatings, nano coatings, CUI coatings.
- Inhibitor coatings (C1 – C4) – anti corrosion paint for metal that releases a chemical which interferes with the electrolyte and stops the corrosion process.
For example: all oil based coatings with corrosion inhibitor additives such as zinc, aluminum, zinc oxide and so on.
- Galvanic coatings/Cathodic protection (C3 – C5) – metal-rich coatings 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.
For example: hot dip galvanizing which provides steel (cathode) with a layer of zinc (anode).
Apply corrosion resistant coating by dipping or spraying
The two most common methods for applying an industrial grade corrosion resistant paint are hot dip galvanizing and thermal (metal) spraying. Barrier coatings and corrosion inhibitor coatings can also be applied by spraying or dipping.
- Hot Dipping is the process of immersing a metal in a bath of metal, often molten zinc (or a polymer), 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 galvanizing uses the principle of cathodic protection, as the zinc coating acts as an anode to its substrate.This method is most common in applying a corrosion resistant coating for steel.
- Thermal (metal) spraying applies zinc or aluminum 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 melts 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.
The best corrosion resistant coating for steel is a Duplex System
When hot dip galvanizing is used together with a top coat of anti corrosion paint or powder it is known as a Duplex System. This is one of the most-used steel coating systems that effectively protects from corrosion.
It provides multiple types of protection and the longest-lasting results. Each coating layer needs to be compatible in order for the system to work effectively. It is especially suitable for corrosion categories C3 to C5 and looks like this:
- Preparing the surface: derusting, blasting, removing grease, oil, dirt for optimum adherence.
- Applying a primer: hot dip galvanization OR applying an inhibitor coating primer depending on the coating system of your choice.
- Applying a sealer: to seal the corrosion resistant paint. Often epoxy based.
- Applying an intermediate coat: there may be several layers necessary for optimum protection, depending on the corrosion category.
- Finishing the job with a topcoat: provides appearance and surface resistance, often first line of defense.
Corrosion resistant paint & spray for smaller projects
For smaller substrates or do-it-yourself application up to category C2, painting at home 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 other metal surface. In spray form it can protect for up to a year. Keep in mind that more exposed areas which are getting constant abuse from rain and salt will need spraying regularly. In paint form, longer lasting results can be accomplished depending on the anti corrosion coating system you choose. For the best result always opt for a two component coating with corrosion inhibitor additives, for example a zinc rich epoxy coating.
Find a professional anti corrosion coating specialist in the UAE
Keep in mind that for categories C4 and C5 it is not recommended to apply metal protection paint yourself. Please search out a specialist.
If you are looking for a professional company to apply corrosion resistant paint for you, it’s important to understand how an anti corrosion paint price is established before you request a quote. Different coating processes use different methods to calculate the cost of professional application. Hot dip galvanizing prices are usually calculated by weight. The galvanizer will quote a price per ton, and then use the weight of your steelwork after galvanizing to calculate the final cost. Unlike galvanizing, powder coating prices tend to be calculated by size or surface area. Whether you need a barrier coating or a zinc coat, corrosion resistant coating suppliers are available for your needs.
Regional differences in materials, labour, and equipment can all have an impact on overall costs when contracting a coating expert. If you want to receive a custom made quote for anti corrosive paints, please contact us.
Here are a few examples of local anti corrosive paint suppliers and specialists in the UAE:
|Anti rust paint suppliers||Address|
|Anticorrosion Protective Systems||P.O.Box: 8091, Dubai|
|Bin Sari Specialized Technologies – BSS TECH||P.O.Box: 33464, Abu Dhabi|
|Mutawa Corrosioneering||P.O.Box: 72642, Abu Dhabi|
|Gulf Sail Engineering Corrosion Services||P.O.Box: 8856, Abu Dhabi|
Globally the leading anti corrosion paint manufacturers include companies like Jotun, AkzoNobel, PPG, Sika and Sherwin Williams. The products of these manufacturers are often trusted by the professional anti corrosion paint applicators.