Powder coating is an extremely popular coating method, for items ranging right through from heavy equipment to paperclips. This is because it provides coatings that are thick, smooth and durable – for superior resilience and finishes that are reliably flawless.

However, powder coating is a specialised service. It requires significant upfront investment in the right setup, including a suitable space and powder coating equipment. Below we outline why this type of coating process may be worth considering and what you need to start a powder coating line.

Why consider powder coating?

Investing in a powder coating line can be a way to:

• Start a successful business venture
  Powder coating is the method of choice for coating a vast and diverse range of items. Many manufacturers outsource powder coating to specialist businesses, rather than setting up in-house facilities. This means a good powder coating service is always in high demand.
  
  
• Improve your company’s existing coating process
  Powder coating isn’t the best solution for every coating need – but for a lot of applications, it has advantages over traditional spray painting. Once a facility is set up, it offers very fast coating for improved productivity. It can also transform the quality of products, providing finishes that are exceptionally durable and aesthetically pleasing.
  
  
• Move your coating process in-house

If your business currently outsources a high volume of finishing work, having an in-house powder coating facility may save time and money over the long term. It may also improve control over quality and turnaround times.

What it takes to set up a powder coating facility

A powder coating line requires an appropriate environment and the right materials and equipment, depending on what you need to coat.

Suitable premises

You need enough space to house items to be coated and the coating line itself. An ideal powder coating environment will need:

• good ventilation, with air circulation and extraction of dust and airborne powder overspray from the spray booth
• surfaces/ racks that are dry, stable and clean, to prevent coating issues
• temperature and humidity control: 20°C to 25°C (68°F to 77°F), with humidity below 50%, is optimal for application and curing
• static control, to prevent uneven powder application
• compliance with local regulations for safety, handling and waste disposal.

These conditions help ensure durable finishes, process efficiency and safety.

Pre-treatment space and materials

Items may require treatment before powder coating to ensure optimal adhesion. This may involve cleaning, abrasion through surface etching or sanding, phosphate or chromate coating (to improve the corrosion resistance of metal surfaces), rinsing and drying.

Powder application system

Dip coating is possible. However, most powder coating is achieved using powder coating guns. A gun gives the powder an electrical charge, which is attracted to and bonds with the prepared surface.

A good quality powder coating unit ensures even distribution of the powder while minimising overspray.

At SCT, we recommend the Airstatic Powder Coating Unit with an Automatic Powder Coating Gun, which can be used in conjunction with a reciprocator or oscillator for automated powder coating.

Spray booth

You’ll need a spray booth of an appropriate size to contain the paint and keep contaminants out of the coating. For high volumes of coating work, multiple booths might be needed.

Curing oven (with hooks and racks)

A convection, infrared or hybrid curing oven is required to cure the powder coating. This must be done at a precise temperature and for a specific amount of time.

The choice of curing oven will depend on factors such as the type of powder coating used, your production volume and specific operational needs. You may also require racks and hooks to hang products so that the coating isn’t marked during the curing process.

An appropriate powder coating product

Powder coatings fall into two main categories – thermoplastics and thermosets.

Common thermoplastic powders include polyester (the most common), polyvinyl chloride (PVC), polyolefin and nylon. Thermoplastics can be reformed multiple times with heat and are resistant to wear, impact and chemicals. Polyester, for instance, is highly weather-proof and durable, making it suitable for outdoor equipment or exposed parts.

By contrast, thermosets harden permanently when baked. This makes them resistant to very high temperatures but also more brittle. Types of thermoset powders include epoxy, an epoxy-polyester hybrid (which is softer and less prone to cracking), acrylic and silicon-based powders.

Thermoset coatings are extremely durable and heat-resistant. However, epoxy coatings can degrade under UV light, limiting their use to indoor applications.

Powder recovery system

A powder management system is optional but recommended. This automates the capture and reuse of over-sprayed powder. This reduces waste and eliminates the need for labour-intensive reintegration of powder.

Protective gear

Operators should wear personal protective equipment (PPE) when working with powder coating materials. This includes respirators, gloves, goggles and overalls.

At SCT, we specialise in surface coating technologies, including powder coating equipment and systems. We offer expert advice based on your needs, budget and facility. Contact us for more information or advice on what you need to start a powder coating line in South Africa.