METHOD AND DEVICE IN A DRYER SECTION OF A FIBRE-WEB MACHINE, SUCH AS A PAPER OR BOARD MACHINE

The invention relates to a method in a dryer section of a fibre-web machine, in which at least one drying group employs single-wire draw in which a paper web (W) that is being dried runs on support of a drying wire (F) such that the drying wire (F) presses the web (W) on a drying cylinder (10) against heated cylinder surfaces, and the web (W) remains at the side of the outside curve of reversing cylinders (11) situated between drying cylinders (10). For the purpose of enhancing the runnability of the web (W), a runnability component (20) is placed in a pocket space (T) confined by two adjacent drying cylinders (10) and a reversing cylinder (11) situated between them and by the drying wire (F). In the method, the web (W) is passed from the drying cylinder (10) to the reversing cylinder (11) as a short transfer, the length of which transfer is 80 - 400 mm, and during the transfer a negative pressure effect produced by the runnability component (20) is applied to the web (W) and to the drying wire supporting it, which negative pressure effect is confined to be applied to the transfer of the web (W) by means of seals of the runnability component (20) against the surface of the drying cylinder (10) and against the surface of the reversing cylinder (11). The invention also relates to a device in a dryer section of a fibre-web machine, in which at least one drying group is a drying group which applies single-wire draw, and in which drying group a runnability component (20) is placed in a pocket space (T) confined by two adjacent drying cylinders (10) and a reversing cylinder (11) situated between them and by a drying wire (F). The drying cylinder (10) and the reversing cylinder (11) of the drying group are placed with respect to each other in such a way that the transfer of the web (W) from the drying cylinder (10) to the reversing cylinder (11) is short, that the length of the transfer is 80 - 400 mm, and during said short transfer a negative pressure effect is arranged to be applied by means of the runnability component (20) to the web (W) and to the drying wire (F) supporting it. For the purpose of confining an area of the negative pressure effect, seals of the runnability component (20) are placed so as to be directed against the surface of the drying cylinder (10) and against the surface of the reversing cylinder (11). L'invention concerne un procédé dans une section de séchage de machine à bande fibreuse, dans lequel au moins un groupe de séchage emploie un