Fast Color Change Powder Coating for Home Appliances

After multiple customer lab trials between competitive powder system suppliers, Nordson was chosen for advanced color change systems and precision control with robotics for porcelain enamel and organic powder on consumer home appliances.

In the customer’s words, “The lab at Nordson was one of the main decision points in choosing Nordson to help us launch our green field plant install.

Not only did we have multiple platforms of new enamel ovens to determine the process, we also had hundreds of prototype units to build for product development.

First and foremost, they wanted Nordson to come to the table with new and innovative solutions. Another requirement was to not have piles of powder on the floor while in operation.

The customer said that they did not want to spend a lot of time cleaning the booth, even if the booth was in an off-line position.

They also wanted a low profile design that would allow them to decrease the distance between the conveyor and the floor, thus avoiding steep conveyor elevation changes. Finally, the customer requested a good looking and “dressed out” system that would hide all of the hose, tubing and cable runs typically associated with a powder system installation.

Nordson was able to provide all of these system elements that the customer requested – and more.

In all, Nordson provided a total of eleven systems housed within three separate rooms. Nine of the booths have the ability to roll on and off line allowing for both fast color change in less than two minutes, and the ability to clean off-line. In the first room, six systems were sold to coat oven cavities with PE ground coat and PE top coat.

The top coat can be applied with either blue PE or gray PE depending on the end product requirements. The top coat booths in the cavity coating room are equipped with robots carrying multiple guns.

The robots provide precision control of the PE allowing the customer greater repeatability and uniformity, and fast cycle times. These efficiency improvements result in higher production capacity, less rework, and fewer rejects.

The second room contains three PE booths to coat oven tops. Similar to the cavity coating room, each system has the ability to roll on and off line. The first booth in line applies a ground coat. The second booth applies a white bisque top coat. The third, booth is dedicated to black top coat. Each system contains four gun movers with multiple guns for faster coating as well as three manual guns for reinforcement of specific areas of the part.

The third and final room in the facility contains two systems that apply organic powder to trim parts for the ovens. These parts do not require PE coating because they are not exposed to the higher temperatures that the oven cavities and oven tops are exposed to. Both systems roll on and off line. The first booth in line is a ColorMax®cyclone based system capable of changing colors in seven min[1]utes or less. The customer runs a number of colors through this system. The second system is also a ColorMax quick color change system.

Not only did we have multiple platforms of new enamel ovens to determine the process, we also had hundreds of prototype units to build for product development. We were able to robotically apply porcelain, determine the process parameters in the Colormax quick color change booths, fire the cavities, and measure the quality of the coating we applied. Having access to these systems allowed us to start up and launch the finishing system on schedule”.