The Process of a Powder Coating Line

Parts moving though powder coating line

Powder coating eliminates the mess and imprecision of traditional painting processes. The liquid-free finishing process offers increased durability, colorfastness, and efficiency. Powder coating lines build on the efficiency of the process with the addition of a production line. Parts and assembled pieces move through a powder coating line on a conveyor system to maximize turnaround times without sacrificing the high-quality results powder coating offers.

How Powder Coating Lines Work

Professionals use powdered thermosetting polymers, plastics and additives to create a hard, pigmented coat on metal surfaces. The basic process uses ESD (electrostatic spray deposition) technology to apply the powder to the surface of the product. The powder will fall off the product at this stage. Heat changes the chemical nature of the powder and allows it to bond to the surface of the metal and create a strong molecular structure.

Powder coating is a multi-step process. Each step ensures the powder adheres to and transforms the surface of the part. All powder coating processes use roughly the same steps, but automated powder coating lines increase productivity for high volumes projects and can handle more parts at one time. Consider the process:

Preparation

Powders will not properly adhere to dirty, rusty, or lubricated parts. Professionals must thoroughly strip and clean the product before sending it into a powder coating process. Powder coating lines may include a multi-step cleaning process involving sandblasting for rust and debris removal, degreasing, washing, chemical etching for improved adherence, and/or phosphating for corrosion prevention. 

A debris- and chemical-free surface will allow the powder to sit evenly and bond better during the heating process. Automated preparation programs take the guesswork out of preparation and cleaning processes. The parts move into the cleaning system and receive uniform treatment and drying before entering the next stage of the powder coating process.

Powder Coating

Powder coating lines use conveyor systems to pull parts directly from the preparation process into a powder coating unit. The surface area of each product is manually powder coated to ensure complete coverage. Technicians must adjust sprayers and pigmentation levels to create single- and multi-color applications for various metal substrates.

Curing

The last stage of the powder coating process adheres the powder to the metal product. A powder coating conveyor line will move the batch from the coating unit to an appropriately heated bake oven for curing. Heat allows the polymer system to permanently bond to the metal and offer a sleek, uniform, and durable coating without drips or blemishes. The product leaves the oven and cools before leaving the powder coating line for packaging or assembly. 

Powder coating lines feature some form of preparation, coating, and curing stage, but the individual approaches within each stage may vary. The line can conduct all three stages simultaneously to deliver continuous output for high-volume parts orders. Strong line systems feature durable and heat-resistant conveyor systems that carry the product movement through each stage. The size of the system dictates the quantity and size of the metal pieces that qualify for automatic line service. Powder coating lines can enhance any metalworking project with durable, even, and visually appealing finishes.

Swanton Welding Company, Inc. offers a complete powder coating line system in addition to other standard painting options. We use high-quality powder coating sprayers and a Stage 1 heated conveyor oven to coat and recoat metal pieces of all kinds. Reach out to us at (419) 826-4816 today to learn more about our powder coating finishing services.

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