When the heat is on production equipment, threatening to shut production down, enclosure cooling systems can get parts out the door, eliminating loss of future production and downtime. That’s exactly what happened to Lasercraft Inc. (Fairfield, OH), a manufacturer of precision laser-cut metal parts. When a summertime heat wave brought its production equipment to a screeching halt, Lasercraft General Manager Jeff Hauck searched the Internet for a permanent solution. What he found were compressed air-powered Cabinet Coolers from EXAIR Corp.(Cincinnati).
The back story reads something like this. Most of the country experienced scorching heat during a recent summer when temperatures soared to record levels. When the heat wave hit in early June, Lasercraft’s manufacturing facility in Cincinnati was uncomfortably warm, but production ran without a hitch.
However, by mid-July, temperatures continued to rise and the 90°F+ days combined with heat put out by the shop’s laser cutting machine raised the temperature of the non-air-conditioned shop over 100°F. Soon, the heat took its toll on the electrical enclosures of the laser-cutting machine. The computer produced many error messages and then stopped operating. Lasercraft tried numerous times to get the program to run without success.
As it turned out, the main CNC circuit board had failed and required shipment to Australia (the laser manufacturer’s principal location) for repair. The situation got worse. It took three days to get a temporary replacement computer cabinet. On top of that, the heat in its free-standing control cabinet was shutting the computer monitor off. This meltdown left Lasercraft no choice but to move the job to its Cleveland location until the repairs could be made. The need to keep the company’s good reputation intact and meet delivery times made finding the proper cooling product Lasercraft’s first priority.
“Of course, I wanted to come up with something that was permanent so that this would never happen again,” Hauck said. “Opening the panel doors wasn’t an option due to safety concerns of having exposed electronics. Mounting panel fans made no sense because the temperature in the shop was too hot to provide cooling.”
Hauck considered various solutions, including heat exchangers and air conditioners. He determined the heat exchangers would be impractical since there would be very little difference between the hot cabinet temperature and the outside surroundings. In addition, air conditioning would be a maintenance project of its own, requiring keeping filters clean and Freon charged.
“After finding EXAIR on the Internet, I recalled seeing their Cabinet Cooler. Honestly, I had my doubts that something so small could deliver the cooling we needed, but I was pleasantly surprised after installing it. The EXAIR staff calculated the cooling capacity and told me there was a 30-day, no-risk guarantee. I figured I had nothing to lose, so I ordered it and it arrived the next day,” said Hauck.
While Lasercraft was waiting on their repaired computer board, they outfitted the cabinet for their laser cutter with the UL-Listed Cabinet Cooler system. Lasercraft also purchased a second NEMA 12 Cabinet Cooler system to mount on top of the control panel monitor.
The EXAIR Cabinet Cooler is powered by compressed air that enters the vortex tube and is converted into two streams, one hot and one cold. Hot air from the vortex tube is muffled and emitted through the vortex tube exhaust. The cool air is discharged into the control cabinet through the cold air distribution kit. The displaced hot air in the cabinet rises and exhausts to the atmosphere through the cabinet air exhaust at a slightly positive pressure. Thus, the control cabinet is both cooled and purged with cool, clean air. Outside air is never allowed to enter the control panel.
Most important to Lasercraft was the fact that there are no moving parts to wear out, making the Cabinet Coolers maintenance free. The only requirement was clean, dry, oil-free compressed air at 80-100 psi (551-689 kPa). EXAIR’s system provided a filter/separator for removing dirt and water from the compressed air to keep the inside of the enclosure contaminant free. Since Lasercraft’s compressor system was a few years old, the shop also purchased an optional oil removal filter to keep oil from the compressed air from passing into the enclosure.
Both units purchased by Lasercraft included thermostat control to maintain 95°F (35°C) inside each of the cabinets. This is accomplished with an electrical thermoswitch that actuates a solenoid valve. It turns the compressed air on only as needed to minimize its use. The 95°F thermostat setting allows the enclosure temperature to stabilize well below the 104oF (40oC) limit of the electronic components inside, without going extremely low, which would waste air. The thermostat accuracy is ±2ºF of that setting, so there isn’t a risk of failure.
“It’s hard to believe that you can get so much cooling out of one of those little tubes,” said Hauck. “In the cool mornings, it never operates but as the day heats up, the thermostat turns the Cabinet Cooler on and off in short bursts to maintain the temperature in the enclosure.”
Lasercraft soon realized an additional benefit. Prior to installing the Cabinet Cooler, it seemed that dust and smoke in the environment always seemed to infiltrate the electrical enclosures on many of its machines. It was typical to open the door of a machine and find a black, sooty mess covering the
insides. The EXAIR Cabinet Cooler kept the enclosures sealed, preventing dirt and dust from getting inside.
“As a matter of fact, we have recently added one of EXAIR’s NEMA 4 Cabinet Cooler Systems to one of our CNC lathes just as a precaution, even though there is a Freon air conditioner already on it. I’ve seen how gummed up those filters get with the coolant and dirt. I don’t want this to happen again,” said Hauck.
Lasercraft now considers these Cabinet Coolers to be a good insurance policy against the summertime heat conditions that had just cost them a significant amount of money. “We learned a very expensive lesson,” said Hauck. “As a result of the electronics failure, it was necessary to move the balance of the job to our Cleveland facility. It slowed our productivity and surprised us with enormous repair costs and freight charges. It cost us nearly $15,000 to get our equipment back up and running,” Hauck concluded. Preventing that from happening again was a wise business decision.
For more information from EXAIR Corp., go to www.exair.com, or phone 800-903-9247.