foerfarande foer avlaegsnande av vatten fraon i fiberbana, speciellt fraon i pappers - eller kartongbana och i vaotpress i i pappersmaskin foer tillaempning av foerfarandet.

摘要

In the process for the press treatment of a fibre material web, in particular a paper web or cardboard web (W), a press nip (NL) is used which is formed between two press rollers (10, 11) and through which the web (W) to be dried by pressing is carried by a cloth or a water-absorbing belt or passed between cloths (17, 24) and/or a water-absorbing belt. In addition, one or more elastic press belts (30) are passed through the press nip. The maximum pressure force (pmax) to be exerted in the process is selected between an upper limit (p2) and a lower limit (p1), the upper limit (p2) being less than 130 bar and less than the function p2max (L) which, with increasing length (L) of the press nip, is a decreasing function whose curve is determined mainly by the maximum available pressure momentum (Imax), and the lower limit (p1) being greater than 50 bar. The diameters of the said press rollers (10, 20) are selected in such a way and, as the said press belt, an elastic belt (30) is used whose thickness, construction and viscoelastic material properties are selected in such a way that, in the abovedefined range (p2-p1) of the maximum pressure force, the following length range (L) for the extended press nip (NL) confined between the rollers (10, 20) is designed with the following upper limit L2 and lower limit L1: L2 200 mm, ... Original abstract incomplete. IMAGE