Understanding the tech behind power coating
Paint has often been a key element in the design and appeal of manufactured products, regardless of the industry. From car panels to house fences, the finish of the paint can be a crucial factor in the appeal of the product. However, in many cases, the paint not only has to be visually appealing but functional.
For many industries, the paint is a vital part of the finished product and getting the paint applied correctly is a crucial part of the production process. When applying paint, there are several options for how to achieve a high-quality finish.
One of the most effective but less well known is powder coating. This is a technically complex process requiring specialist equipment, but the end results have significant benefits to the finished product.
The first thing to understand about powder coating is that it is primarily used on metals, but new methods are being developed to coat non-metal objects. The reason powder coating is usually done with metal objects relates to the process and technology used, which also lead to the benefits of the process.
Before any coating can take place, the metal object needs to go through some pre-treatment. This process is vital to clean and prepare the metal to receive the paint powder later on. A method such as shot blasting is often used to clean the metal. This removes any dirt or imperfections, which could hamper the adhesion of the paint at a later stage, by using iron grit.
Once the metal is ready to be coated, it is moved into a special clean room. Here the metal is earthed, giving it a negative charge. However, the paint receives a positive charge after it is applied through an electrostatic paint gun. This works by using compressed air to force the paint powder through the gun, inside which an electrode provides a positive charge. Because of the difference in charge between the paint powder and the target object, the paint and metal are magnetically attracted to each other along with the force of the compressed air.
Once the whole target piece is coated in paint powder, the piece is baked in a curing oven. This is a key part of the process as it changes the chemical makeup of the paint. The paint powder melts and forms a smooth layer of paint on the metal. This heat not only helps the paint particles adhere to the metal but also to each other, as the chemical crosslinks in the paint particles are joined together, forming a highly durable coat.
Because of the two processes involved in powder coating, the differences in charge creating an attraction between the paint and the metal along with the curing process, the finished coat is significantly more durable than traditional wet paint options. For this reason, powder coating is highly desirable for objects which may need to function in harsh environments where temperature or debris could affect the paint. Car enthusiasts also turn to powder coating for protection against chips and scratches on parts such as wheels and bumpers.
Powder coating has been popular in the manufacturing sector for a while, but increasingly businesses are working with individuals to powder coat objects for their home or garden. The same benefits of a high quality even finish, and durability are desirable for radiators as much as car wheels!
