New technology boosts productivity of aluminum-sheet annealing

Sheet aluminum for auto and truck bodies remains the top growth area as the industry shifts to lighter-weight vehicles. Now a new technology from Linde for continuously annealing cold-rolled strip aluminum may soon speed production. Details about the new technology will be presented at TMS 2015, March 15-19, at Walt Disney World in Orlando, Florida.

In a paper titled, "Direct Flame Impingement (DFI) – a new oxy-fuel based technology for continuous annealing of aluminum strip," Linde senior nonferrous expert Henrik Gripenberg will discuss DFI technology, applications, and pilot test results. The presentation, part of the Aluminum Processing Symposium, session 1, is scheduled for March 16th at 2:50 p.m., at the Dolphin - Southern Hemisphere I.

With Linde's Direct Flame Impingement technology, oxyfuel flames directly heat the metal strip as it passes through the annealing furnace. The process can achieve heat transfer rates up to 10 times higher than those in conventional fuel-fired furnaces. The Linde DFI technology has been boosting productivity of continuous steel hot-dip galvanizing lines for nearly 10 years, with capacity increases in excess of 25 percent.

As automakers race to satisfy new 54.5 mile-per-gallon corporate average fuel-efficiency (CAFE) targets for 2025, they are planning to use more aluminum in doors, hoods and other parts beginning in the next few years. Aluminum is about one-third lighter than steel, and a 10 percent reduction in weight means about a 7 percent improvement in fuel economy for the life of the average vehicle.