METHOD FOR CALENDERING A PAPER OR CARDBOARD WEB COATED AT BOTH SIDES

To achieve desired treatment results at both sides of a material web to be calendered, the material web is initially guided through a first nip formed between yieldable elastic surfaces confronting the throughpassing material web. In the first nip there is predominantly applied a relatively high pressure to the material web. Then the material web is guided through a successively arranged second nip formed between practically non-yieldable hard surfaces confronting the throughpassing material web. In the second nip there is applied, apart from pressure, in particular heat to the material web. The treatment result achieved in the first nip, namely the smoothness and glaze values of the treated material web, are augmented at both sides of the material web to achieve desired treatment effects.