Steel painting system should be chosen according to the corrosion level of the environment and type of the application.
1. What is Painting?
Ferrous metals, including steel, are susceptible to rusting because of their iron content.
Steel is painted for a variety of purposes; aesthetics, corrosion protection and longevity. The selection of paint system to be used dependent on a number of factors, such as site conditions where the finished steel is going, expected lifespan of the steel and aesthetic appearance.
A proper surface preparation is essential for the quality of the steel painting system. This may include processes such as shot blasting and grinding to remove any imperfections or burrs on the surface which may affect the quality of the outcome.
Paint is generally applied to steel through airless spray, air spray, dip coating, or a roller;
- With airless spraying, the paint is hydraulically compressed and released through a small nozzle in an airless spray gun to be projected onto the surface work piece.
- With air spray, the paint takes the form of a fine mist and is applied to a surface with the use of compressed air;
- Dip coating is used when the entirety of a work piece is lowered into the paint tank for a full coverage.
- A roller can be used to paint surfaces by hand; this works best for small surfaces such as touch up paints.
2. Types of paints
- Primers
The primer is first layer of paint to be applied onto the cleaned steel surface. Its purpose is to wet the surface and to provide good adhesion for subsequently applied coats.
- Intermediate Coats
Intermediate coats are applied to increase the total film thickness of the system. The main principle is the thicker the coating the longer the life.
- Finish Coat
The finish coat provides the required visual appearance and surface resistance of the system. It is also the first line of defence against the environmental corrosion such as weather and sunlight, open exposure, and condensation.
- Intumescent Paints
Intumescent coatings are passive fire protection measures which swell up when heated (in a fire for example) and cover the material. As the intumescent layer swells up, it increases its surface volume, which then prevents the heat reach to the material. Intumescent coatings are generally available as water-based or solvent based variations.
3. Other Coating Types
- Powder Coating
Powder Coating is the process of applying a dry free flowing powder to a surface which is electrostatically charged and then cured under heat so the coating forms a skin on the item.
The major difference between powder coating and painting is that powder coating does not require a solvent to stick to the surface.
Powder Coating is environmentally more responsible than other solvent based coatings as there are zero volatile organic compounds.
Powder Coating offers a broad range of colourful and visual finishing compared to the other means of coatings which makes them the favourite coating system for appliances, street furniture and similar frequently used products made of metal. Also powder coating offers very good corrosion protection for external environmental conditions.
- Hot Dip Galvanization
Galvanizing offers a metallic long lasting anti corrosive cover to protect carbon steel from the elements. Hot Dip Galvanization has a very long lifespan without any maintenance requirement. The exact life span heavily depends on the corrosive level of the environment.
Being one of the most costly coating application, hot dip galvanization is performed in specialized facilities by dipping the work piece into several tanks in a sequence assuring proper cleaning and coating. Hot dip Galvanization is one of the toughest and reliable coating and used across the board within the fabrication and construction industry.
4. What is Novelty Steel offering?
Novelty Steel is an experienced steel fabrication with extensive painting capabilities. Novelty also serves its clients with 3rd party galvanization partners.
With vast CNC Machinery Park and experienced engineering team, Novelty Steel performs high quality paint and coating works according to the EN 1090-2 European Norms.
Recommended Blog Articles
Selecting right paint for steel provides protection against corrosion assures that the most economical and [...]
Steel is a robust, resilient and durable material which can main its structural integrity [...]
Steel structure paint types are selected primarily based on the application of the product and [...]
Gallery