Abstract: A plant (10) for the production of corrugated cardboard comprising: a corrugating unit (36) adapted to produce containerboard, and a double baker (60) adapted to receive the containerboard. The corrugating unit (36) is positioned in proximity to an output end (66) of the double baker (60). The plant (10) further comprises a transfer unit (72) adapted to receive the containerboard and move it. The transfer unit (72) comprising: an input end (722) for the containerboard positioned in proximity to the corrugating unit (36), and an output end (724) for the containerboard positioned in proximity to an input end (64) of the double baker (60).

Abstract: An apparatus (1) for processing sheets of paper material, comprising: a calender (2) adapted to treat at least one sheet of paper material and including a first cylinder (3) and a second cylinder (4), the first cylinder (3) comprising a work wall (3a) of composite material, forming the outer work surface (3c) of the first cylinder (3) and a support body (3b) having an outer surface coaxial to and in contact with the work surface (3a), the first cylinder (3) being obtained by fitting of the work surface (3a) on the support body (3b).