What is powder coating and its advantages?
What is Powder coating?
Powder coating is a dry finishing process that has become extremely popular since its introduction in North America over in the 1960s. Representing over 15% of the total industrial finishing market, powder is used on a wide array of products. More and more companies specify powder coatings for a high-quality, durable finish, allowing for maximized production, improved efficiencies, and simplified environmental compliance. With powder, processing time is reduced Powder processing times are generally shorter than those used for wet stoving paints since, as there is no solvent, no flash off period is required. Instead, the powder coated articles can pass directly into the oven. This gives substantial saving in space and time.
The Advantages of Power Coating!
- Applying powder is much cleaner than applying wet paint. A spray booth can be cleaned down quickly and easily using a rubber squeegee whilst the normal air extraction in the booth is operating. Brushes or an air hose should not be used for this purpose. Any spillages of powder outside the booth can be removed with an industrial vacuum cleaner which is fitted with an air-driven or dust-tight motor.
- There is no costly wastage of solvents which, at application viscosity, constitutes up to 70% of conventional liquid paints. These solvents, which volatilise during application and stoving are usually not recoverable. Legislation introduced in various parts of the world has prohibited their discharge into the atmosphere which means in some cases after-burners have to be installed to eliminate the solvents with an attendant increase in costs.
- Water wash spray booth are often used with liquid paint systems. The over-spray is often emulsified in the water, which in some cases is put directly to drain or in other cases, allowed to settle out in sludge tanks. Powders do not give rise to these problems and the associated extra costs.
- As powders do not contain solvent there is a marked reduction in nose, mouth and throat irritation. With liquid coating, any liquid paint which comes into contact with an operator’s skin needs to be washed off with solvent, and then removed by emulsifying with soap in hot water. Sometimes special industrial hand cleaners even have to be used. In general powder does not cause skin irritation though in rare cases individuals may react to certain types of powder. The powder can be removed from the skin easily by washing with warm water.
- Is not just metal that benefits form powder coatings. Surfaces such as glass and certain thermo-setting moldings which can withstand the stoving temperatures involved can be powder coated. The scope of materials which can be used is ever-increasing as advancements in lower bake technologies are made.
Conclusion
For the majority of high production work, powder coating reveals itself as a viable alternative to other types of coating in terms of cost savings, environmental impact and durability. While certain items will continue to be liquid painted for reasons of feasibility and practicality, powder coating provides an alternative which, for its cost and other factors, is difficult to ignore.