Abstract: A crushing device includes a casing with an inner wall, a rotor having a vertical axis of rotation, mounted in the casing and formed by a disk having a working surface with radially arranged fractionating blades mounted thereon and each including a working lateral face and a lateral face opposite to said working lateral face and each consisting of a main portion rigidly secured relative to the rotor disk and located nearer to the rotor axis and a peripheral portion pivoted to the rotor disk, rotatably mounted about the vertical axis, and having a section radially extending beyond said disk, and stationary grinding elements placed on the inner wall of the casing and arranged coaxially with the rotor disk.

Abstract: An apparatus for producing fibrous sheet material comprises a slot nozzle having side walls normal to converging frontal walls, its inlet opening communicating with means for dispersing fibers in a gas stream, while its outlet opening communicates with a chamber. A flat screen adapted to form a fibrous layer thereon is mounted under the chamber, and a suction box is arranged underneath the flat screen, wherein the side walls of the slot nozzle are parallel with respect to each other, and means for removing part of the gas from the gas-fiber stream are provided in the chamber under the outlet opening of the slot nozzle, the chamber being provided with branch pipes for gas exhaust, mounted substantially in the upper portion of the chamber.

Abstract: A method for producing fibrous sheet material comprising dispersing fibers in a gas stream to obtain a gas-fiber stream, supplying the gas-fiber stream onto a flat screen, removing gas from the gas-fiber stream through said screen to form a fibrous layer thereon, removing part of the gas from the gas-fiber stream prior to supplying it onto the flat screen, simultaneously damping transversal pulsations induced in the gas-fiber stream during the course of its movement. The fiber concentration is increased to 20-500 g/m.sup.3. The fiber concentration is chosen in accordance with the specific fiber and its properties. An apparatus for carrying out this method comprises a slot nozzle having side walls normal to converging frontal walls, its inlet opening communicating with means for dispersing fibers in a gas stream, while its outlet opening communicates with a chamber.