Coating machine
A primary reel, on which paper deficiencies can be removed, is superposed to the coating machine. To bridge set-up times at the coating machine, this primary reel has to operate at a higher speed than the paper machine. It has an unwinding system, designed for use of a flying splice. Next, the paper is coated. First on one side, followed by drying. Then the other side is coated and dried. For drying purposes, infrared- dryers, airfoils and drying cylinders are used. Rolls with gyratory grooves and wide plug-in reels provide safe reel guidance through the coating machine.
The heart of the coating machine, however, is the coating unit with the integrated coating aggregate. Under each coating unit, a workstation pumps up the coating mass from the preparation tanks, where the colour is mixed. These tanks, made of stainless steel, are cooled to avoid coating sticking to the walls and clot formation. The coating has to be permanently filtered and aerated to avoid deficiencies, such as blade streaks. Automatic control systems conti- nuously monitor and adjust coating quantity and humidity of the coating.