Understanding Fluidized Bed Powder Coating and Its Benefits For Your Product

Whether you’re a product designer, engineer, or original equipment manufacturer (OEM), creating a product out of metal has many benefits. However, it has several downfalls. Most metals are prone to corrosion, wear from oils in the human skin, damage from diverse types of weather, and poorly maintained grip. That’s why many workers across dozens of industries turn to fluidized bed powder coating to provide a thick, substantial layer that offers excellent durability, resistance to wear and rust, and a more comfortable grip.

But how does fluid bed powder coating work, and will it provide the right coating you need for your item? When you work with experts in the powder coating field, like Precision Coating Technology & Manufacturing (PCTM), we’ll ensure that you understand the process and benefits of this type of powder coating and get the best fluidized bed coating for your product.

For over 30 years, we’ve helped industries like yours get the coating they need to extend the longevity of their unique product. We understand what it’s like to be excited about new product development, only to be disappointed by other coating materials like paint that don’t provide the same advantages as powder coatings. That’s why we specialize in coating parts using a wide variety of coating techniques that provide the resistance, durability, and color options you want.

What Is Fluidized Bed Powder Coating?

You may already be familiar with powder coatings – finely ground powders that cling to metal or other substrates and are then baked on. Fluidized bed powder coating is a coating process where finely ground powder particles are put in a tub, and air is forced through the bottom, creating an effect like quicksand.

This ‘fluidizes’ the powder, allowing your preheated equipment to be quickly and completely covered in a protective coating. The particles melt on contact to fuse with the object, providing a consistent, even finish on metal parts.

This type of powder coating is ideal for low-complexity and detailed parts that need a thick, even layer. Due to the thickness of the coating, if the metal part is stamped with something like a serial number or other small detail, the fluidized powder will cover it up and make it unreadable. However, the positive to this coating is that if there are minor imperfections on the metal object, the fluidized powder will also conceal it.

What Is Fluidized Powder?

The fluidized powder is the material used in a powder coating fluidizer. These powders have a larger particle size. A thermoplastic powder is typically used because it melts when introduced to heat and hardens as it cools. It can also be remelted, unlike thermoset materials. The powder paint is either made from polyvinyl chloride (PVC), nylon, or polyethylene.

A bed of one of these powders sits at the bottom of an open box. Beneath the box is a porous membrane, and under the membrane is a plenum chamber. This chamber is a pressurized housing containing positive pressure. The air flows through the housing and porous membrane.

This air causes the powder to act like a liquid, and the heated object is dipped into the liquidized powder coating. The air causes the volume of powder to expand for easier dipping. For example, 24 inches of powder increases to 28 to 30 inches deep. The fluidized powder then coats the metal object and bonds to the surface due to the heat.

How Does a Fluid Bed for Powder Paint Work?

When you give us your equipment to coat, it is treated with utmost care and concern. All metal parts are cleaned to remove soil. They can either be sandblasted and/or primed to increase the adhesion of the coating. The part being powder coated with fluidized bed coating then goes through a four-stage process:

1. Part is Preheated

The metal part must be preheated in an oven to at least 350 degrees Fahrenheit, but ideally, 400 to 450 degrees, as it will cool slightly during transfer. The piece needs to be at a higher temperature than the melting point of the fluid bed powder so that the powder quenches or cools the part right away during the submerging step. A conventional gas-fire convection oven is the most common way to heat the item.

2. Part is Dip-Coated

The air pump causes air to flow through the powder coating fluidizer, suspending the powder particles into a fluid-like state. We dip the hot part into the fluidized bed of powder coating and move it around for a complete and continuous coating.

3. Part Remains Submerged

We keep the part submerged in the fluid bed for powder paint to allow thick, wear-resistant coating to set completely. The coating’s final thickness depends on the object’s heat before being dipped in the bed and how long it is left in the fluid bed of powder coating.

4. Part is Post-Fused

The final stage of fluidized bed powder coating is the post-fusing process. After excess powder drips off the product, it moves to an oven at a lower temperature to cure. The post-heat in the range must be at a lower temperature than the preheated oven. This step aims to ensure that all the powder has adhered to the part during the dip and melts into a smooth, uniform coating. If the oven is too hot, the bed-dipped object could cause the coating to melt off, sag, or drip.

What Are Some of the Benefits of Fluidized Bed Coating?

PCTM’s fluidized bed powder coating options are specifically designed to give your metal object the smooth, even finish you want. This method of powder coating application can instill dozens of benefits and traits in your products, including:

• Environmentally Friendly: Some of the most ecologically harmful compounds, such as volatile organic compounds (VOCs), come from solvent-based liquid coatings. Our powder coatings are far safer than other coating methods for the environment and users.
• Uniform Coating Thickness: A fluidized bed completely immerses your equipment, ensuring an even coating. Other treatments, such as liquid coatings, can result in dripping and sagging that creates weak areas where the layer is thin.
• Efficient Application: This powder coating process has high transfer efficiency, meaning there is little waste compared to other methods. The lower material use can result in cost savings for you and your business.
• Wide Range of Compatibility: Fluidized bed powder coating is a versatile application method that can be used with metals, some plastics, ceramics, and glass. This versatility is an attractive benefit if you are a business that works with diverse equipment.
• Adhesion and Durability: Because these coatings are baked on after coating, a powerful adhesion ensures that your equipment will have maximum protection – protection that will last far longer than other coating methods.

Want Fluid Bed Powder Coating For Your Parts? Call PCTM!

Are you excited at the idea of having equipment that is resistant to corrosion, wear, and weather? If you want improved tools and equipment, fluidized bed coating is the way to go! It’s ideal for large objects without delicate details or areas where the fluidized powder could build up.

And when you need a partner to give you a consistent fluidized bed powder coating, choosing PCTM is smart! We are in the heart of Central Pennsylvania and have the machinery and expert operators who perform our coating technologies.

We understand the challenges you face when using metal to craft your objects, which is why we make it easy to get the powder coating your product deserves for longevity and durability. Simply request a quote from our team, send us your product, and we’ll take it from there! You’ll receive your product back with a beautiful, high-quality powder-coated finish.

Editor’s Note: This blog has been updated since its original publishing for accuracy and comprehensiveness.