Such was the case for an extensive ventilation/exhaust system installed during the fall of 2005 at Altec Industries' welding and fabricating facility in St. Joseph, MO. Altec, in business more than 75 years, is an equipment and service provider for the electric utility, telecommunications, and contractor markets. Despite Missouri's sometimes cooler and windy climate, the building only requires limited supplemental heating and no air conditioning.
Improved IAQ a must"Our biggest issue has always been improving the building's air quality," said Pat Francis, an Altec production supervisor. He said an unexpected advantage caused by the overall installation has been how plant air is more evenly distributed for enhanced circulation, which allows thermostats to be turned down and reduces cold spots.
Seaman & Schuske Metal Works coordinated efforts for the two-phase project to help eliminate welding smoke from Altec's 75,000-sq-ft manufacturing site with 20-ft and 30-ft ceilings.
Darrell Moppin, project supervisor for Seaman & Shuske, said ventilation equipment had to first be put in place before a rooftop exhaust system could be installed during the second half of the project.
Great Lakes Air Systems installed cartridge collectors in September. Each unit, known as a RoboVent, has 48 filters to remove unwanted fumes and return clean air back into Altec's fabrication plant.
"The ventilation system moves 226,000 cfm and provides about eight ach," Francis said. That means the six collectors each handle approximately 12,500 sq ft of the total facility footage.
Six weeks instead of eightMoppin said it took a four-man crew about six weeks to mount the exhaust system's 2,500 ft of ductwork during November and December. For faster installation, he said the crew utilized Ductmate's Bullet Band self-sealing duct connectors in 24-in., 30-in., 34-in., and 42-in. sizes.
Only one Bullet Band is required for each spiral connection, allowing the job to be completed with only 400 connectors. "That's one for each joint," Moppin said. "In comparison, had we used a different clamp such as angle rings, we would have needed 800 rings and the entire job would have required 8,000 bolts for system connections."
He explained the device is actually an expanding connection that eliminates the need to apply sealants or tapes, achieving SMACNA Class 3 leakage requirements. As added security, however, Moppin said the crew installed from three to six additional screws per duct section depending on pipe size.
"Because there were limited screws necessary, we were able to place 20-ft sections of the 24-in. pipe in about 5 minutes and 10-ft sections of the 42-in. pipe in about the same timeframe" Moppin added. "That saved about 40% to 50% in labor costs and eliminated two weeks off the job."
Beating the weatherNot even the weather could slow down the installation with average temperatures between 15° and 35°F. Since it took place during the cold winter months, conditions on the roof often proved challenging with the crew experiencing anything from rain, sleet, snow, and harsh winds.
Mike Crane, territory manager for American Metals Supply, which is a distributor of Ductmate products, originally suggested the Bullet Band to Moppin due to the project's slated installation timeframe. "With winter fast approaching, I knew the device would make for an easier install and help save on union labor costs," Crane said.
Before the installation could begin, however, Moppin said the crew had to seal storm collars to prevent weather from entering the manufacturing facility and they spent several days creating a staging area on the roof so necessary materials were readily available.
Though the duct could have been installed inside, he said Altec selected the roof location to maintain aesthetics within the building. Duct rested on split angle rings to keep it off the roof, providing easy and safe access for maintenance while also offering structural integrity for the entire roof installation.
In addition, Moppin said the Bullet Band helped straighten out ducting and easily covered minor imperfections in pipe cuts. "The whole process worked out better than we anticipated."
Francis couldn't agree more. "We are very impressed with the overall system, especially how fans are able to clear the air in just 15 minutes. Ironically, we've discovered that venting air from the outside has virtually eliminated former cold spots since warmer air is being circulated."