Smart Architectural Aluminium is the largest manufacturer of aluminum profiles for windows, doors, facades and conservatory roofs in the UK.
At its production facility in Yatton near Bristol, aluminum profiles are coated in three lines, two vertical and one horizontal. Here the products are first powder coated and then passed through infrared gas catalytic ovens to gel the powder before passing through the convection oven for final curing.
The gas catalytic infrared panels for the horizontal line were installed about ten years ago. Over time, their efficiency had suffered because free powder that had migrated from the vestibule of the furnace had contaminated them. This caused quality problems in the production process and so the company contacted Heraeus Noblelight in order to arrange for the installation of new panels.
However, the infrared experts at Heraeus Noblelight suggested an alternative solution. Instead of simply renewing the gas catalytic panels, an additional electrical infrared booster in front of the furnace could provide the decisive improvement. The booster would quickly bring the applied powder into a gel state and thus avoid any powder carry-over onto the panels in the gas catalytic furnace. Complete gelling could then be achieved in the furnace before the coated parts were transported into the convection furnace for final curing.
This plan convinced Smart Architectural Aluminium, especially as the infrared booster could be easily mounted on the existing steel structure in the vestibule of the gas catalytic furnace. Since the installation of the medium wave infrared emitters, which were fixed in an aluminum frame with stainless steel reflectors, the system has been working extremely successfully.
As Michael Coles, the paint plant manager at Smart, comments, “The IR booster, which was retrofitted easily in existing space in the vestibule, has provided us with a simple but elegant solution to a possible contamination problem, increasing panel working life and improving product quality.”
Efficient curing with optimum energy use
Powder generally absorbs infrared radiation very well, so the powder mass heats up quickly and gels much faster than in a convection oven. Without air movement, dust inclusions are avoided and the powder is not swirled or carried away. Rapid fusing improves the paint quality and increases the throughput speed.