Disruptive technology in manufacturing comes along rarely, but when it does, it can have a huge impact. The use of infrared (IR) in curing powder was pioneered around 25 years ago and prompted a major rethink within the entire finishing industry. Many described that technology as disruptive, and it is fair to say that there has been pushback from various corners of the finishing industry, some would say to the fear of fear itself.
Now, as manufacturing technology continues to improve and after years of practical experience, clever thinking is still being applied, and new applications are still being found for old disruptive technologies. In the case explained here, three companies working together have developed an improved coating process that provides a highly corrosion-resistant finish to ferrous substrates.
It Starts with a Zinc-Rich Primer
The story begins with Miller Electric Manufacturing Co. of Appleton, Wisconsin, the world’s largest manufacturer of arc-welding products. If you ever come across a blue-arc welder, it is probably from Miller. As the equipment is utilized in many industries and applications, its mild steel casings and panels need to be as corrosion-resistant as possible.
Enter TCI Powder Coatings of Ellaville, Georgia, a major manufacturer of powder coatings in North America and long-standing supplier to Miller that offers a widely used zinc-rich primer. A zinc-rich powder primer can provide superior protection to zinc electroplating when correctly cured and topcoated.
Focused on continuous improvement, Miller needed to improve the efficiency of its finishing plant. It was using a two-cycle process that necessitated running the parts twice through to apply and cure both primer and topcoat.
Miller began considering whether gas catalytic IR could shorten cure times, deliver energy savings, and improve quality, processing time and work space. It brought IR specialists from Heraeus to the table for their advice.
Soon, the powder supplier and IR supplier started working together, exchanging ideas and carrying out some testing. One solution involved the removal of a separate final cure process from the priming stage, and the results were dramatic. Removing just this single step enabled the reduction from a two-pass to a single-pass process, and this reduced the overall cycle time by 50 percent.
Read more: Gas Catalytic IR: The Technology Enabler