METHOD FOR INFLUENCING AT LEAST ONE OPERATIONAL AND/OR QUALITY PARAMETER IN THE PRODUCTION OF A FIBROUS MATERIAL WEB AND SHEET FORMATION SYSTEM FOR CARRYING OUT THE METHOD

摘要

The invention relates to a method and to a sheet formation system for influencing at least one operational and/or quality parameter in the production of an at least single-layered fibrous material web (2). It is characterized in that a pressure impulse (D.7, D.8; D.7, D.7', D.8), which is produced by a free jet (14) and in particular which changes depending on the free jet length (L.14), on the angle of incidence (α) and/or on the resistance (R.7, R.8) of the screen (7, 8; 7), is measured on the side of the screen (7, 8, 7) opposite to the at least one fibrous material suspension (3) applied to the screen (7, 8; 7) by way of a sensor (17.1 through 17.3, 18.1 through 18.3, 20.1 through 20.3, 21.1 through 21.5, 22.1, 22.2, 23.1 and 23.2), preferably by way of two or more sensors disposed in the transverse direction of the machine (CD), and that the at least one measured value (M.7, M.8; M.7, M.7', M.8) obtained from the pressure impulse measurement is on the one hand used to reproduce an operational parameter that can be described through the free jet length (L.14) and the angle of incidence (α), for example the intake geometry, and/or is used on the other hand to adjust a quality parameter, in particular to optimize a quality parameter, of the fibrous material web (2) to be produced by changing the position of the material take-up s (4) and/or the position of the at least one de-watering element (9.1; 16) of the screening part (6), in particular the entire screening part (6).