Infrared drying of aircraft components on a large scale
By Elodie Lutz
By using infrared drying, an aircraft manufacturer shortens the drying time for the coating of aircraft landing flaps to one sixth of the previous burn-in time. “The system was developed for drying three jobs, which are run in a circle one after the other to apply the base coat, the top coat and the antifriction lacquer,” says Stefan Wollenweber from IWT Infrarot-Wärmetechnik GmbH. “Previously, there was always a bottleneck at this point of production, as the drying step took about 60 minutes. The drying time should be drastically shortened with the IR dryer. That’s what we did.” Today, the average drying time is only ten minutes. Not only the drying time, but also the heating and cooling phases are enormously reduced.
In the current application, different landing flap geometries of up to 12 x 3 x 0.25 m are fully automatically retracted into the approximately 1.5 m wide radiator cabin. The parallel radiator walls contain 112 individually controlled zones with 420 kW installed power. The temperature can be regulated individually in each zone. After two minutes, the target temperature of 80 °C is reached on the painted surface. The system automatically reduces the initial output by 88-90% in order to maintain the temperature for the required eight minutes drying time.
The system is program-controlled and is operated via a visualization system. If a new component geometry is included in the production, the settings can be entered directly here. This process, including test measurements, usually takes no more than one day. Neither for new settings nor for the normal operation of the plant there is no need for any special settings.
However, not only the geometry, but also the coating colour plays an important role in infrared drying. Their different reflection behaviour is taken into account in the program via offset factors. Light coatings require about 5 – 10% more power than dark coatings because they absorb the radiation less well.
IWT infrared heat engineering GmbH, Limeshain, Stefan Wollenweber,Tel. +49 6047 9508-50, email@example.com, www.iwt-infrarot.de
Source: IWT infrared heat engineering GmbH