A Straight Line to a Quality Finish

By integrating a compact, continuous flow powder coating line, this steel service center prospered from a raw material supplier to a manufacturer delivering a finished product. The company’s investment has preserved floor space, lowered operating costs and improved labor efficiency.

Contributed by Marty Sawyer, CEO, Trimac Industrial Systems

For American Steel & Aluminum (ASA), adding powder coating to its capabilities redefined the business. What began as a steel service center has quickly evolved into a complete steel fabrication job shop operation. Bringing powder coating in-house became the final step in delivering complete, finished parts to customers.

According to Tim O’Sullivan, vice president and general manager, the decision was driven by customer expectations and operational control. “Three years ago, we were outsourcing all our powder coating to Canada,” O’Sullivan said. “They did a good job, but we had a new customer come in that was not thrilled with outsourcing. That’s when we knew we needed to look at doing this ourselves.”

At the time, the company, in Auburn, Massachusetts, was making a major, single-year capital investment across the facility, adding a Trumpf laser, as well as press brakes, welding stations, blasting and forming capabilities. Powder coating was the missing link.

“We were moving from supplying raw material to supplying finished product,” O’Sullivan explained. “We needed to be able to take raw steel or aluminum, fabricate it, coat it and ship a part that our customer could install directly into their equipment.”

This panoramic view of American Steel & Aluminum’s (ASA) shop floor (top) looks past the environmental room to the dry-off, washer and loading station.

From Outsourcing to In-House Powder Coating

When ASA began evaluating powder coating systems, the company explored batch and continuous flow solutions. While batch processing could have met the needs of one customer, it would not support the high-volume, high-variability mix anticipated for future growth.

“We really needed continuous flow,” O’Sullivan said. “We expected a large volume with a huge variety of different parts.”

That requirement narrowed the field quickly. Continuous flow systems offered the throughput and consistency necessary, but they also introduced challenges related to space, energy use and operating costs especially within an existing facility.

Bottom photo: The pretreatment washer and dry-off oven at ASA include an additional module for preheating parts.

Selecting the Right Technology and Partner

An ASA customer recommended finishing systems manufacturer, Trimac Industrial Systems (Bonner Springs [Kansas City], Kansas), to O’Sullivan as an option for its equipment needs.

While visiting the company, both convection and infrared curing technologies were reviewed and considered by O’Sullivan. But the gas catalytic infrared oven quickly became the favored option, largely because of how operating costs and environmental concerns were addressed. 

After contacting different systems manufacturers, O’Sullivan made his choice. “We solidified on Trimac pretty quickly,” he noted. “Their response time was much better than other companies that were in the running, and they did a good job explaining what the system could really do.”

Finding the Optimal Line Layout

Early layout concepts followed more traditional rectangular looped designs, with the washer and dry-off oven on one side and the powder booth and cure on the other.  However, as the design progressed, it became clear that a conventional footprint would consume too much valuable manufacturing space.

“We started with a layout that wrapped around one bay, then two bays,” O’Sullivan said. “That’s when we really started to worry about how much floor space this one operation was going to take.”

Through collaboration between the two companies, the layout was refined into a straight-line configuration installed against a back wall in a 25-foot by 345-foot space. The return loop was then against the wall, so all equipment was compressed into one continuous path.

The system minimized its footprint while preserving open space for fabrication and material handling. Most important, it delivered the production volume needed while still being flexible enough to handle the variety of parts a job shop powder coater might want to coat.

“The straight-line design wasn’t the original goal,” O’Sullivan explained. “The design was the outcome of trying to keep as much floor space as possible for manufacturing.”

The Trimac system delivers a part from load to unload in 60 minutes, supporting a lean operation. The system design consists of the following equipment:

·        5-foot per minute, 4-inch I-beam monorail conveyor system (handling up to a 1,000-lb load)

·        four-stage pretreatment washer designed for zirconium

·        multi-zoned Trimac Gas-Cat dry-off oven

·        environmental (EV) room with 10 automatic guns and booth setup provided by Nordson Corp.

·        multi-zoned Gas-Cat 10-minute cure oven and a heat dissipation tunnel to deliver parts quickly to unload

The system is designed to accommodate parts up to 3-feet wide by 5-feet tall by 20-feet long.  

A Straight-Line System Built for Efficiency

The final system integrates pretreatment, dry off, powder application and infrared curing in a single, continuous flow. Parts load on one end, then move forward through each stage and unload at the other end, all in a straight line. The conveyor then returns empty. The return conveyor was installed much closer to the wall; no space is needed for operation or material handling.

This configuration also supports efficient staffing and automation. Typically, there are one to two operators to load the line, one to two unload, and one operator doing touch up. This was accomplished over the first year of operation as experience grew.

“When we first started, we had three people loading, three unloading and one in the booth,” O’Sullivan said. “Now we’re often running with two on each end and one in the booth and sometimes even fewer, depending on the parts.”

However, the reduction did not happen overnight. “We were brand new to powder coating,” he added. “There was a learning curve, and Trimac was on-site multiple times helping us improve the process.”

Why Gas Catalytic Infrared Made Sense

Infrared curing played the critical role in enabling the compact layout while maintaining process flexibility. By delivering energy directly to the coated surface along with the oven zoning, the gas catalytic infrared system reduced oven length significantly and enabled faster response to changing part requirements. 

The system also enabled adjustments to manage operator comfort and environmental conditions, because infrared (light) energy, not hot air, is the primary heating mechanism.   This meant less hot air had to be controlled from escaping the ovens into the work area. 

ASA’s system also was designed to support the variety of parts a custom coater would be coating, including complex parts. Trimac’s ThermalWrap system was part of the oven design to assist the infrared energy by recirculating air throughout the ovens to help oven balancing as well as drive heat conduction into hidden areas.

Marty Sawyer, Trimac CEO, explains, “Our ThermalWrap air system was developed decades ago and helps customers cure their complex parts. The design balances the oven and keeps thinner metals for overheating while the infrared keeps heating the thicker or hidden portions. Hot air does not turn corners any more than light energy does. Therefore, to get the hidden areas cured, the conduction process must be accelerated to enable the part to help cure itself. The higher temperature of infrared accelerates. With this air system, customers get fully cured parts in minutes.”

This flexibility enabled ASA to adapt without major mechanical changes. “With infrared, you can dial things in,” O’Sullivan noted. “With convection, that’s much harder to do.” 

This gas catalytic infrared cure oven, Gas-Cat from Trimac, uses electromagnetic radiation, or invisible infrared light, generated from a flameless gas reaction with a catalyst to heat materials. Infrared heat waves are long, electromagnetic waves located near the visible part of the electromagnetic spectrum. These waves can give off a large amount of heat that is easily absorbed by surfaces when directed using a reflective shield.

Adaptability of System Design

After less than two years in operation, a major adjustment to the system has already been installed.

“One of our customers came back and asked for much heavier film builds—8 to 12 mils,” O’Sullivan said. “With Trimac’s help, we were able to increase heat on the part to support that.”

To accommodate ASA, additional modules were added to the end of the dry-off oven to support the heavier film build. Although Trimac installed the original system, the modules were so easy to add that shop was able to install them without assistance.

Launching Job Shop Powder Coating

From the outset, ASA intended to offer powder coating as a service, not just for its own fabricated parts, but for external customers as well.

While the continuous system favors volume, the company remains comfortable handling a range of part geometries and applications. The ability to offer fabrication and finishing under one roof has become a competitive advantage.

“It’s not just about being a job shop,” O’Sullivan explained. “We sell our capabilities. We can take raw material, transform it, coat it and deliver a complete product.”

This four-stage pretreatment washer’s overhead conveyor forms a loop that flows through this multi-process line. The washer provides increased throughput, safety, repeatable results and are especially useful for high volumes of similar parts.

Results Beyond the Equipment

Today, the powder coating system operates as part of a broader, integrated manufacturing operation. Floor space has been preserved; lower operating costs are a competitive advantage and labor efficiency has improved as automation and capabilities have increased.

Above all, the system supports the company’s long-term strategy. “This was all part of a bigger investment,” O’Sullivan said. “We knew exactly what equipment we wanted, and powder coating was a critical piece of that plan.”

The straight-line infrared system might look unconventional compared to traditional layouts, but for ASA, it represents a practical solution to real manufacturing constraints and a clear path to delivering a quality finish.

Parts are quickly cooled in the heat dissipation tunnel and ready for unload at the end of the tunnel.