Method and device for dewatering of a paper web by pressing.

摘要

Method and device in the manufacture of paper or board for dewatering of the paper web (W) that is being manufactured. The paper web (W) is transferred from the forming wire (10) onto the wire (80) in the drying section while constantly on support of a fabric that receives water, a transfer fabric, or of any other, corresponding transfer surface (105 min ) as a closed draw, at a particularly high speed, which is, as a rule, higher than about 25...30 m/s. Dewatering of the paper web (W) is carried out by means of at least two subsequent press nips (N,NP), of which nips at least one press nip is a so-called extended-nip zone, whose length (z) in the machine direction is larger than z > about 100 mm. The extended-nip zone (NP) is formed in connection with a mobile flexible press-band loop (201; 301). The distribution of the compression pressure employed within said extended-nip press zone (NP) is regulated and/or selected both in the transverse direction of the web (W) and in the machine direction so as to set or to control the different profiles of properties of the web. <IMAGE>