Method of ensuring flatness of a vane in a headbox by means of a mounting arrangement, headbox with such a mounting arrangement, a mounting arrangement and vane therefor

摘要

A method of ensuring the flatness of a vane that is mounted in a headbox by means of a mounting arrangement including engagement dowels for cooperation with a downstream support wall of a transverse groove, said vane being affected during operation by shearing forces from the stock and by retaining forces from the mounting arrangement. In accordance with the invention outer engagement dowels are mounted at the side edges of the vane to cooperate during a specific period of time, as the only engagement dowels with the downstream support wall in order to take up said shearing forces, whereby tensile stresses will arise in the downstream end portion of the vane in the cross machine direction. The invention also relates to a headbox having such a mounting arrangement and the mounting arrangement per se in which the vane within and downstream of an inner area of the upstream end portion of the vane is arranged to move freely in the machine direction in relation to said downstream support wall during said period of time.