| 摘要 |
<p>The invention concerns a press section of a paper or board machine, comprising a number of rolls (1,11,22,32,44,70) which form press nips (N1,N2,N3,N4) that dewater the web (in) with each other, the web being arranged to run through said nips. Of the rolls at least one roll (1;70) is a smooth-faced so-called centre roll, which forms a press nip (N2,N3;N4) with at least one other press roll (11,32;44), over which a press felt (10,30;40), which has been formed as an endless loop, is passed to absorb water out of the web (in) into said press felt (10,30;40). The centre roll (1;70) in accordance with the invention is a variable-crown roll, which comprises a metallic roll mantle (2;71) arranged revolving on a stationary roll axle (3;72). The roll includes at least one set of crown-variation means (4,5;73), which are arranged to load the roll mantle (2;71) in the direction of the nip plane (K2,K3;K4) of the centre roll (1;70) and the roll (11,32;44) that forms a press nip (N2,N3;N4) with said centre roll so as to regulate the profile of linear load in said nip (N2,N3;N4).</p> |
