In the last fifty years, powder coating has grown in popularity. It has become the best and the most common method used for the finishing of automobile and other parts exposed to extreme weather conditions that requires finishing. Our premium powder coating solution offers benefits such as durability, gives a long-lasting finish with a smooth texture that’s resistant to rust or corrosion, scratch resistance, gloss retention, and resistance to chalking.
When giving a product surface a good finish, we all look forward to that magic finish, i.e., easy to apply, looks beautiful, and last forever, but in reality, there is no magic or forever though there is such a thing as a long time which is what powder coating represents. The solution is used to create a hard finish, and it’s tougher when compared to conventional paints. It is usually used for the coating of automobiles, Metals, household appliances, drum hardware, motorcycle, bicycle parts, and aluminium extrusions. Materials such as Medium density fibre boards, composites, carbon fibre, composites, and plastics can also be coated using methods that require less heat and time. All this is achieved with more advanced technology.
Kindly read on as we explore more solutions.
What is Powdercoating?
This is a type of surface paint that is usually applied as a free-flowing or dry powder, and unlike conventional paints, comprising of evaporating solvents, it is applied electrostatically, then cured under heat or ultraviolet light. This protects and also enhances the surfaces of sheet metal parts.
The powder coating produces not sturdy finishes but is flexible and can be used on different surfaces such as plastic, steel, concrete, and metal; it is also suitable for indoor and outdoor applications.
Types of powder coating
When deciding the type of coating, most manufacturers take time to examine the costs and potential coating complexity of the most appropriate coating for their application.
There are different powder coatings types, including ultraviolet curable powder coating, thermoplastics, and thermosets.
1. UV-curable powder coatings:
This is a new technology of coating, and they are photopolymerized materials with a chemical photoinitiator that instantly responds to UV-light energy, starting the reaction leading to cure. It is important to note that powder coatings that are cured with Ultraviolet light offer a faster curing process with a lower temperature requirement.
The UV curable coating for the first time allows material surfaces of some alloys, parts that contain both metallic plastics and wood with other heat-sensitive substrates to be coated.
One advantage of the UV Curable coating is the ability to facilitate higher line speeds and productivity, energy, time, and space savings.
2. Thermosets PowderCoating:
In this type of coating system, more brittle thermoset resins are broken into a very fine powder, which can then be fabricated into an exceptional thin paint-like film that exhibits both the physical and chemical properties similar or comparable to those of liquid-based coatings.
Also, the advancements in thermoset technology have drastically led to the increase in the versatility of the material group, which allows for more customization options.
This type of coating yields better results when the thermoset formula is matched with the corrosion resistance, texture, aesthetic properties, and curing cycle of the products used.
Characteristics
This type of coating employs the capacity to engineer resin types with variable properties designed to suit metal finishing treatments.
The range of characteristics of the thermoset powder coating has led to an increase in specialized roles for thermoset powders, with polyesters and acrylics finding greater use in the automotive and appliance industries despite the traditional reliance on epoxy-based coatings.
Thermoset powders provide a high corrosion level, temperature, and impact resistance. Below are some industrially consistent thermoset powder coatings.
3. Thermoplastic Powder Coating: A thermoplastic coating is a coating that does not react chemically during drying. These coatings are thick and resilient, found on the refrigerator shelves or clothes drying racks, and are effective in providing corrosion protection and weathering resistance.
Thermoplastic powder coating is a type of coating in which particles coat metals by melting as soon as it gets to the desired temperature, and it shows mechanical and chemical strength with cooling.
Properties;
The first powder coatings produced were based on thermoplastic polymers, which melt at the application temperature and solidify on cooling.
Especially in industrial applications, all-metal materials are coated with coating materials before usage because of esthetic, endurance, and safety reasons.
The most important purpose of this coating method is to provide protection against corrosion.
Acrylic Powder coating: Acrylics require curing temperatures close to those of hydroxyl polyesters, and they combine high-quality surface aesthetics with flexibility and impact resistance. They also exhibit excellent alkali resistance, making them well-suited for use on appliances, such as ovens and washing machines. Some of the advantages of using acrylic powder coating are excellent, Outstanding smoothness, good chemical resistance, optical clarity, and water-white colour. Acrylic powder coatings can be effectively applied through electrostatic spraying and have adjustable thin-film characteristics. However, acrylics are more responsive to substrate attributes than most powder coatings, making them incompatible with certain chemical compounds.
Benefits of Powder Coating
Powder coating is safer to use because it does not contain any flammable solvent as we do have in the regular wet paint. VOC, which is Volatile Organic Compounds found in some wet paint and hot plating, are not present in powder coating; it doesn’t contain caustic, which could be harmful when it comes in contact with the skin. This makes powder coating very safe to use.
Efficiency
Because of the electromagnetic energy used to apply the powder to parts, there is almost no waste in the powder coating process. Additionally, an expert can apply as much (or as little) powder as necessary in one application. Rather than allowing the parts to dry between coats, everything is done at once, which saves money and time.
Low Cost
Along with the money you’ll save by eliminating extra steps, powder coating is cost-efficient in a few other ways. The materials used are bought according to the job’s specifications. The powder is less costly than paint, and it takes up less space when stored.
Durability
As far as the finish is concerned, powder coating is more durable than most other options. When it cures, the powder will form chemical bonds in the process and create a flexible, durable finish. The parts that are coated with powder are usually resistant to flaking, scratching, and corrosion.
Environmental Safety
Because the powder is free of toxic chemicals and solvents, it is regarded as safe for usage and disposal. The processes release no harmful chemicals into the air, and they produce less waste. However, expert painters know that inhaling the powder is harmful, so they wear safety gear that minimizes skin contact.
Quality
The powder coating application and drying processes create a finish not found in any other paint product. Because the powder melts and reforms as a solid, it creates a smooth surface without drips or runs. Therefore, there is no need to sand or refinish if mistakes are made.
Maintenance
- Powder coating is easy to maintain; no special solvents or cleaners are required. Because these coatings are so resistant to corrosion and damage, there is no concern over rust and other cleaning-related damage. In most applications, an occasional wipe with soapy water is enough to keep parts clean and useful for years into the future.
Uniformity
Getting a uniform conventional painting is nearly impossible unless it has been applied by a professional painter working in a sterile environment. Every surface of a powder-coated product comes out smooth and perfect to the eye. With powder coating, there are no runs, streaks, or weak spots. There are no imperfections like bubbles, dust bumps, or caught insects.
Processing time is reduced using powder.
Powder coating process times are normally faster than when applying wet 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 extensive savings in space and time.
Appearance
Applying powder coating is much cleaner than applying wet paint. A spray booth can be cleaned down quickly and easily using a rubber squeegee while the normal air extraction in the booth is operating. Brushes or an air hose should not be used for this purpose. Any powder spillages outside the booth can be removed with an industrial vacuum cleaner fitted with an air-driven or dust-tight motor.
Colour Variety
Colours used in powder coating come in a rainbow of selection. These colours can be premixed in powder pigments by the supplier. That’s done in factory settings with computer-controlled mixing ratios. Carefully premixed powders allow for the perfect color distribution, which is very difficult to achieve with wet paint products. Black and white are the two most popular powder coating color choices. However, every color in the spectrum is available in various color blends. While mil-spec powder coating has a few common finishes and colors, one of the biggest benefits of the method is the potential for customization. Powder manufacturers will create unique blends to match any color, texture, and finish. There are few competitive options in terms of versatility and range.
Ease to Paint Angles
Different objects can be powder coated, irrespective of their shape, size, and complexity; if the product can take an electric charge, it can be powder coated. Comparing powder coating to paint or plating, there is no challenge in coloring every surface on complicated shapes with powder coating. Irregularly shaped pieces with tight bends and hollow cavities make it difficult to use wet paint. This gives metal fabricators freedom to design and manufacture one-piece products and not have to paint parts separately for later assembly.
Consumer Recognition
Consumers recognize powder coating as a quality mark. Powder-coated surfaces stand right out to the discerning eye compared to conventional wet painting. Powdered surfaces have a distinguished dry and even look that is unique to the powder coating process. That makes the statement of care and quality that equals value and satisfaction.
Corrosion Resistance
Rusting has always been a problem for metal fabricated products. Outdoor pieces get pounded by rain, snow, sleet and hail. Indoor products also suffer corrosion through high humidity and water exposure. Because powder-coated equipment is so thoroughly and evenly covered, there is no opportunity for moisture to seep through to metal pores. Without question, corrosion resistance is a chief benefit gained by powder coating.
How to Apply Powdercoating
The part’s surface must have proper preparation to achieve the best possible. Preparing each section will depend on the base material, metals, and other materials like fiberglass. In general, the part must be clean and remove any oil or grease on the surface and rinse. Next, the region is etched. Etching helps remove any surface oxides and provides more surface area for the powder coating to stick on. After etching, another rinsing takes place.
The part is dipped in a chemical solution to neutralize the surface. Things will vary as each chemical solution formula design works with a specific base material. On aluminum, it is either a chromate or phosphate solution. Other options include zinc and iron phosphates. These chemicals adhere to the part’s surface and provide the film needed for the powder to stick. Last, the region is demineralized to remove any chemical salts on the surface and prevent any corrosion beneath the powder coating.
The process used to apply the powder is different from other coating systems, thanks to its use of electromagnetic properties. The powder coating application requires some specialized tools, and the powder is placed inside a paint gun that charges the particles using either friction or an electrical source. Next, the part that will take the coat is grounded to provide an opposite charge. The opposite of the particles and the piece for coating will attract the particles when spraying takes place. The thickness of the application will vary depending on whether the coating is external or internal. Or the type of environment that the part is in use. The powder will continue to stick to the part’s surface as long as it is grounded, which allows for multiple passes to cover the piece.
How is Powder Coating Applied?
Most powder coating is applied electrostatically. Generally, we take the following steps when using powder coats to the metal via electrostatic spray:
- The surface to be painted is prepared via sandblasting or some other cleaning/etching process to remove contamination that may inhibit adhesion.
- The powder is sprayed through an electrostatic or cornea gun onto a grounded metal surface. The electrical charge given to the powder by the gun is attracted to the metal’s grounded surface.
- The coating cures at a specified temperature; cure temperatures vary depending on the coating being applied.
- Further coats are added if required.
Other methods of applying powder coatings include “hot flocking” (electrostatic spray onto preheated surfaces) and fluidized bed dipping.
What are the stages in manufacturing powder coating
Producing powder coating is a multi-step process. It can be described as semi-continuous because it begins as a batch process (weighing and premixing) but evolves into a continuous process (extrusion and milling).
This section describes the manufacturing and quality control process for powder coating materials. The state of the art technology used for producing industrial powder coatings consists of several distinct stages, namely:
1. Weighing, premixing, and size reduction of raw materials
2. Extrusion of premix, cooling, and crushing of the extrudate into chips
3. Micronising the chips into the final powder
4. Post mixing, packaging, and storage.
At each stage of the production process, the quality must be checked because once the powder coating material has been produced, it cannot be changed or adjusted in any significant way.
The formulation and the manufacturing conditions are therefore critical. Reworking an ‘out of specification’ product is difficult and costly.
How Does Powder Coating Work?
Powdercoating occurs when the powder has been thoroughly applied on the surface of the object to be coated, and the newly-coated part is placed into a curing oven. After which, the powder melts and adheres to the part, creating a smooth, hard coating.
The granular formed promotes the powder to be evenly applied to a surface more evenly.
Powder coatings are cost-efficient, as they do not contain solvents and volatile organic compounds. Furthermore, over-sprayed powder coating can be retrieved and recycled for use, thereby reducing cost.
Frequently Asked Questions on Powder Coating
Q1-What is the purpose of powder coating?
The main purpose of powder coating is to protect the roughest, toughest machinery and the household items you depend on daily because it guarantees a more durable finish compared to liquid paints by offering an attractive finish.
Q2-Is powder coating better than paint?
Powder coating provides better performance than conventional paints, thus creating a more resistant part to scratching, chipping, and other wear that may occur because of the thermal bonding it undergoes during the curing process and because it can be applied in much thicker layers. In addition to its physical toughness, powder coating provides superior colour retention.
Q3-Why is powder coating so expensive?
Powder coating is generally more expensive than painting because professional tools and labour are required. It also includes surface preparation and the cost of sandblasting, which is sometimes necessary to remove the previous finish before applying the powder.
Q4-Will Powder Coating fill in scratches?
Powder coating is a painting technique that is used on aluminum handrails and many other factory-made metal items. Businesses and customers often prefer this coating because it provides a visually appealing finish. Moreover, the coating adds a scratch-resistant layer to the aluminium, further protecting handrails from the wear and tear of general use and outdoor elements. Powder coating makes your product look more professional and commands a higher price. Many customers specify or demand powder coating for its superior performance.
Q5-What is the maximum temperature it will need to withstand?
You will find that each type of powder coating will have a specific temperature range. High-temperature powder coatings will perform well, but only within the temperature range designed to tolerate.
Q6– WILL POWDER COATING PREVENT GALVANIC CORROSION
Rust is the orange-brown coloring that forms when iron combines with oxygen in the air, leading to corrosion. Therefore, this can be avoided by applying powder coating to the metals to avoid rust because powder coatings are designed to prevent oxidation by keeping the part from exposure to oxygen and water.
The main catalyst for rust to occur is water. Although iron and steel structures seem solid to the eye, water molecules can penetrate microscopic gaps in the metal, which starts the corrosion process. If salt is present, for example, in seawater, the corrosion will be more rapid. Exposure to sulfur dioxide and carbon dioxide will also hasten the corrosion process.
This type of coating usually contributes to the steel’s durability, helping the frame to withstand damages better and last longer. Corrosion-resistant. The humidity and moisture cause metal frames to rust, and thus when used on steel material, it provides an optimum barrier against corrosion.
A safe place to get powder coating materials
In Nigeria, there are places to get powder coating, of which one is Epoxy Oilserv Nigeria Limited. Epoxy Oilserv is a reliable company operating in Nigeria, West Africa, with an office in the United States of America. We have office locations in all major Nigerian cities, covering the remaining part of Nigeria with our capable distributors. We know the importance of creating value for our stakeholders, we are implementing processes and procedures directly in compliance with ISO 9001:2008, we strive to be the best in all we do, with best intentions to limit emphasis on profit only, but more on value creation, we want to serve you as much as you want us to serve you. This powder coating is available at the Epoxy Oilserv.
Conclusion
Powder coating is one of its kind. The powder coating finishes are not only strong but flexible as well. It can be used on different surface areas, including metal, aluminium, and plastic. It is an attractive choice due to environmental advantages.
Contact us for further details on powder coating within the storefront in your location.