METHOD AND APPARATUS FOR CONTROLLING DISTORTION OF FIBRE ORIENTATION IN A PAPER WEB

摘要

Method and apparatus in the head box of a paper machine for controlling the distortion of fibre orientation in the paper web comprise an arrangement wherein by-pass flows of pulp suspension are passed through opposite passages lateral of the turbulence generator preceding the slice portion or discharge channel of the head box. The magnitude and/or the mutual relationship of the by-pass flows is adjusted to control the distortion of the fibre orientation in that the by-pass flows produce a transverse flow in the discharge flow of the pulp suspension from the head box, the speed of which compensates for the distortion of the fibre orientation.