Winding problems with rotogravure jumbo-rolls

Abstract

The production and conversion of jumbo rolls presents a challenge to all involved in the production process. This presentation shows that as reel dimensions continue to increase, limits are being reached with regard to engineering and production. This applies to the paper, the core and particularly to winders and printing machine unwinds. The two problems areas, on the one hand crepe wrinkles and bursts in the reel centre when rewinding and unwinding and on the other hand the danger of the core disintegrating in the winder machine unwind, which can have serious consequences, can only be solved jointly by those involved in the whole process. One effective measure will be to use 150 mm cores instead of the 76 mm core for extremely heavy jumbo reels. This will represent an initial decisive breakthrough to improve the situation. Further optimisation in paper making and converting, in core geometry, strength and stiffness as well as in the design of winders and printing machine unwinds will ensure that the manufacture and conversion of jumbo reels meet the requirements posed.