Jessup Engineering Inc., headquartered in Rochester Hills, Mich., has a reputation for designing high-performance automated finishing systems. The company specializes in engineered-to-order, automated dip-processing machines for a range of industries, including aircraft, marine, automotive and plumbing fixtures, appliances and hardware. In many of these applications, the sophisticated electronic controls must perform in harsh, corrosive environments where humidity and airborne contaminants are prevalent, and this requirement presented a distinct challenge. The company had tried using refrigerant-based air-conditioners but found that they weren't up to the task.
"They would usually perform for about a year or so, and then the environment would start getting into the internal components, and it would become a high-maintenance issue at that point," says Chuck Danto, a control systems engineer at Jessup. "With the air-conditioners not working, then we would have the long-term destructive effects of the heat and humidity and what it would do to the electronic components."
Danto says that the heat generated by the electronics inside an enclosure can be a significant problem, especially in southern climates. "For most customers, floor space is critical, so we tend to pack a lot of electronics into as small of an enclosure as possible," he says. "There are a lot of PLCs [programmable logic controllers], variable-speed drives and equipment for motion profiling that generate heat. It was always a battle between keeping the enclosure completely sealed to keep the environment out -- but taking the tradeoff of the heat and the long-term effects of what it would do."
A Sleek SolutionDanto had used stand-alone vortex tubes for other cooling applications, and he thought this technology might provide a solution for the enclosures. He checked ITW Air Management's web site for sizing information and noticed a packaged unit specifically designed for cooling enclosures.
Danto liked that the compressed-air based system, called the Vortex A/C, delivers below-ambient cooling in environments up to 175°F (79°C) -- as opposed to maximum ambient cooling of 131°F (55°C) for refrigerant-based air conditioners. The system also creates a positive pressure of 1 to 2 psi that keeps the enclosure free of any airborne contaminants and humidity.
"The positive air pressure option that essentially keeps the corrosive environment out of the enclosure was a big selling point for us," he says of the optional "purge-air" port on the system, which creates a pressurized enclosure for complete protection. Additional protection is provided by a 5-μm, automatically draining, compressed air filter that allows only clean, dry, refrigerated air to enter the cabinet.
The compact size, aesthetic appeal and ease of installation of the system also were key factors in Jessup's decision to integrate the nonelectric cooling device into its automation systems, Danto says. With the system's mounting footprint at less than one-tenth the size of a comparable air-conditioner used to cool electrical enclosures, the unit provides advantages in overall system design, packaging and shipping.
"With conventional air conditioning units, we had to go with an 18" deep enclosure, so it would require purchasing a bigger enclosure for nothing more than to mount an air-conditioner on the side," says Danto. "With the Vortex A/C, we can use it with a 10 or 12" deep enclosure. Also, we don't have to size the electrical transformer or the control system power to run an air-conditioner, and that's an advantage to us as an OEM," he says.
The system can be mounted on either the top or side of the enclosure and is designed to ease installation. In fact, Jessup sometimes ships the system separately for customers that want to install it themselves in a new unit or retrofit an existing unit with the technology. "Installation is so simple and straightforward that we don't have to redo drawings or provide engineering documents for them," he says.
Ultimately, however, the sleek and compact appearance of the vortex tube cooling system was the deciding factor for Jessup. "It's funny, but even in the industrial world, a little bit of style goes a long way -- because a lot of times, the control panel is the first thing you see when you walk up to the equipment," Danto says. "When we saw Vortec's new product line [the Vortex A/C], where they took the cooling tube and put it in a small NEMA 4X enclosure, we knew we had a stand-alone, cleanly packaged and aesthetically pleasing product that we could put out there. It really was a product improvement, and the bottom line was packaging."
Jessup Engineering began using the vortex tube cooling system on its equipment in late 2007. According to Danto, the system has eliminated the maintenance and reliability issues Jessup previously experienced with air-conditioners. It has also substantially enhanced overall protection of electrical components while offering a compact and aesthetically pleasing product that is simplifies packaging, shipping and installation.
"One of the phrases we use to describe our equipment is simple, rugged and reliable, and the Vortex A/C fits the bill for all three of those," says Danto. "There is really no maintenance or service involved with the Vortex A/C, so it's one less thing that you have to maintain, adjust or even worry about -- and that makes our customers happy."
This article was contributed by Steve Broerman, engineering manager for the Vortec product line of Cincinnati-based ITW Air Management, a manufacturer of industrial air cooling systems. For more information, call (800) 441-7475; e-mail firstname.lastname@example.org; or visit www.itw-air.com.