Clupak

The Clupak process is used in the paper industry, for the manufacture of stretchable paper, and consists of increasing the elastic capacities and the resistance of paper within the production process. This provides paper suitable for the manufacture of multi-fold bags, which are capable of withstanding large loads without breaking. The system is mounted in the drying section of the paper machine, and consists of a cylindrical rubber mat, which rotates and is pressed against a dryer cylinder through which the paper slides. The effect is achieved by passing the rubber blanket over a space less than its natural thickness, which causes it to stretch and increase its speed due to the venturi effect. In this way, when it passes to the other end, the stretched gum is compressed to recover its usual thickness, which produces microdeformations in the paper and rearrangement of its fibers, which gives the paper its extensible character.

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