Patent ID: 8382955
Filing Date: 2013-02-26
Classification: D21F

Abstract:
1. A method for operating a sheet forming unit for a machine for producing fibrous webs, in particular paper, cardboard or tissue webs from at least one fibrous stock suspension, the machine including a headbox and a forming unit arranged downstream from the headbox, comprising the steps of: feeding the at least one fibrous stock suspension to the headbox over a machine width of the machine; forming partial flows of the at least one fibrous stock suspension as the at least one fibrous stock suspension is led into a plurality of turbulence generating channels and to a nozzle from which the at least one fibrous stock suspension is applied or respectively delivered in the form of a free jet onto a clothing or between two clothings of the forming unit defining a line of impingement, whereby within at least one of said turbulence generating channels a pressure loss (Δp) is set in the at least one fibrous stock suspension; producing said pressure loss Δp in a final fluidization region of said at least one turbulence generating channel upstream from an inlet into said nozzle of ≧50 mbar; and leading the at least one fibrous stock suspension from said final fluidization region to said line of impingement so that a dwell time (T