Abstract: An arrangement for fastening a grindstone (1) of a pulp grinder to a rotatory shaft (2). In the arrangement, the radial forces acting on the grindstone are transmitted from the fastening flange (3) of the grindstone (1) to the rotatory shaft (2) by means of a support member (12) which transmits the radial forces from the fastening flange (3) through the support member (12) to the rotatory shaft (2) in such way that they do not substantially affect the threads (8), (9) of the nut (7) and the rotatory shaft (2).

Abstract: A method for feeding a wood batch into a pressure grinder, according to which method the wood batch is first fed into a pressurizable feeding device (9) and thereafter from the feeding device into a continuously pressurized grinding chamber (5) to make contact with a grinding means (3) rotating in the grinding chamber. The wood batch is fed from the feeding device into the grinding chamber essentially in a horizontal plane in the direction of the axis (4) of rotation of the grinding means for maintaining proper order of the wood batch during the feeding operation. In a feeding device for carrying out the method the feeding device (9) is positioned on the side of the grinding chamber (5) so that the bottom (10a) of the feeding pocket (10) formed by the feeding device is essentially in level with the bottom (5a) of the grinding chamber. The feeding device is provided with a pushing means (17) displaceable in the feeding pocket towards the grinding chamber in parallel with the level of the bottom.

Abstract: A sealing arrangement for a shutter for a feeding chamber of a continuously operating pressure grinder. The feeding chamber is provided with an inlet opening for feeding wood batches at atmospheric pressure into said feeding chamber and with an outlet opening for feeding said wood batches into the grinding chamber at overpressure. Each opening of said feeding chamber is provided with a shutter movable between an opened position and a closed position for preventing of escape of said overpressure through said feeding chamber.The feeding chamber is provided with a fixed guide supporting the shutter during its movement between opened and closed positions. Said guide comprises two parallel support surfaces between which the shutter is slidably mounted. The distance between said support surfaces is greater than the thickness of the shutter adjacent said support surfaces so that the shutter is displaceable towards and away from said support surfaces in a direction perpendicular to said support surfaces.