Abstract: In order to enable a satisfactory degree of barking when removing the limbs and bark from wood in a barking drum having internally a plurality of log lifters and a plurality of slots arranged around and along the drum for the discharging of waste material freed, said drum comprising two axially aligned drum halves each comprising a main treatment section with a transition section located between them, said transition section is provided with a separating section comprising an arresting surface for the waste material and an annular outlet opening cooperating with the arresting surface and arranged in the dividing plane between the two drum halves, for discharging limbs and bark caught by the arresting surface.

Abstract: Multilayer paper of superior layer purity and formation is produced by discharging a plurality of superimposed jets of papermaking stock from a headbox into the throat of a roll former, preventing the discharged jets from coming together for a short distance by introducing air between adjacent jets as they leave the headbox, and maintaining the velocity of the jet closest to a plain forming roll in the roll former slightly higher than the velocity of an adjacent discharged jet.

Abstract: A method for forming a multilayer jet by delivering a plurality of superposed, spaced apart jets of stock through a slice opening towards a web forming zone, keeping the jets separated for part of the distance between the slice opening and the forming zone, and thereafter, but not later than the arrival of the jets at the forming zone, allowing the jets to come into direct contact to produce a stratified jet. Separation of the jets in this fashion is effected by forming and maintaining gaseous wedges in the spaces between them after delivery through the slice opening.

Abstract: A headbox for paper and pulp machines is pivotally mounted at the ends of a plurality of control links secured to the machine frame and pointing from the machine frame towards a center of rotation in the vicinity of the headbox slice opening. The angular relation and the vertical position of the headbox with respect to a web forming zone are accurately set by controlling the rotation and translation of the respective control links and the headbox thereafter is maintained rigidly fixed in the set position.

Abstract: Methods and apparatus for producing a web by injecting a jet of stock between two tensioned wires and running the wires over a circumferentially grooved forming cylinder. The cylinder grooves and a zone immediately on the other side of the wires extending from the forming throat where the web is injected to the web run-off point are in direct, open communication with the ambient atmosphere so that water is drained inwardly and outwardly of the forming cylinder as the web is being formed. The jet stock size, wire speed and wire tension are adjusted in relation to the radius of the forming cylinder so that the inward and outward drainage of liquid from the web occurs in relative amounts sufficient to avoid substantial two-sidedness of the web thus produced.

Abstract: The present invention relates to propeller blades which are mounted in a rotatable propeller hub and pivotable in the same by means of inner shafts with axes substantially radial to the axis of rotation of the hub and countersunk in said hub and located inside an outer peripheral edge of the same. The propeller hub is positioned in an shroud means, a tunnel or similar with a surrounding wall, which is substantially circular and concentric to the axis of rotation of the hub. The propeller blade has a blade vane with an outer edge with portions shaped as peripheral arcs concentric to the hub axis and having a play to the surrounding wall which is smaller than the necessary radial movement which is required for the lifting of said shaft over the peripheral edge of the hub when the propeller blade has to be demounted from the hub.