Abstract: The apparatus comprises a centrifugal pump (1) fed by a screw feeder (8). The screw feeder comprises a screw (9) with a partially open thread (11). The screw (9) is driven separately in opposed direction to and with a lower speed than the impeller (3) of the pump (1). By this arrangement pulp of high concentration can be pumped.

Abstract: Methods and apparatus for continuously mixing fluid processing media with pulp suspensions are disclosed. The method includes supplying pulp suspensions to the central portion of the substantially planar radial face of a cylindrical rotor, feeding a fluid processing medium to the pulp suspension as it approaches the rotor face, forming an annular gap at the axial outer surface of the rotor, so that the rapid rotation of the rotor causes the pulp suspension and fluid processing medium to flow radially outward along the planar face and to pass axially through the annular gap, and effecting turbulence between the pulp suspension and the fluid processing medium at the entrance to that gap.

Abstract: The invention relates to a defibrator comprising at least one rotary cylindrical drum provided on its inner surface with longitudinal deflectors, driven in rotation and axially supplied with material which is to be defibrated. On the inside, the defibrator comprises a rotor consisting of a shaft coaxial with the cylindrical drum, and longitudinal blades branching off radially from the shaft and having ends which are curved in the direction of rotation, capable of receiving the material which is to be defibrated and of projecting it on to the inner wall of the drum.

Abstract: A rotary grinding disc in an apparatus for refining fibrous pulp material, comprising a plurality of arcuate grinding plate segments disposed annularly about the disc and supported thereon by means of wedge-shaped tongues projecting from the segment plates and dovetailed into grooves of corresponding profile in the disc, the wedge-shaped tongues and dovetail grooves decreasing in width from an outer radial portion toward an inner radial portion, or vice versa, for wedging the plate segment into the disc. The plate segments may be additionally secured against disc placement by the effect of the centrifugal force during rotation of the disc by means of a peripheral ring surrounding the disc and engaging the wedged tongues.

Abstract: A grinding apparatus in which lignocellulose-containing material such as wood chips is ground in a grinding space defined between cooperating disc segments carried by a rotating disc and a stationary disc in close spacing tolerance. In order to counteract the deflective centrifugal force exerted on the rotating disc segments, the peripheral portion at the rear of the rotating disc is formed with an annular bulge having an annular channel therein for receiving mercury in an amount calculated to generate during the rotation of the bulging disc a counter centrifugal force equal to the deflecting centrifugal force exerted on the rotating grinding segments to thereby maintain the close tolerance spacing between the cooperating grinding segments.

Abstract: Methods and apparatus for separating vapor from refined cellulosic material are disclosed. The method includes discharging the refined cellulosic material downwardly through an inlet opening into a discharge chamber maintained at substantially the same pressure as the refiner, deflecting the vapor laterally with respect to that cellulosic material, passing the vapor through the discharge chamber at a flow rate of less than 15 meters/sec. so that the cellulosic material carried by the vapor is separated from the vapor by sedimentation, and discharging the cellulosic material from the discharge chamber.

Abstract: Screening apparatus for fractionating material suspensions has a screen gap which is defined by a rotatable member and a stationary member. One of these members is provided with at least one projection which extends into the screen gap to inhibit clogging of the gap with coarse suspension materials. Any coarse suspension materials stuck in the screen gap can be removed from the screen gap by a wiper element extending from the rotatable member and overlapping the screen gap.

Abstract: Apparatus for refining lignocellulose-containing material is disclosed, including a refiner housing, a pair of counter-rotating refining discs within the housing, one of the discs including a feed passage for refining stock and the other disc including a steam passage therethrough to permit steam to exit from the refining space between the discs, channel means rotatable with that refining disc which includes the steam passage in order to conduct steam therefrom through the refiner housing, and passage means located outside of the refiner housing for conducting away steam exiting from the channel means.

Abstract: Method and apparatus for producing fiber pulp of improved paper-forming characteristics from ligno-cellulose-containing material such as wood chips and the like. The pulp material is subjected to a defibrating process in at least two steps. In the first step, the pulp material is disintegrated in a defibrator to form a flocculent mass of initially separated and freed fibers. This flocculent mass is then passed through a screw compacting device in which it is subjected to compression of a magnitude of 1 to 5 times the volume of the initially separated fibers. The compressed and highly concentrated mass of initially separated fibers is then passed into a refiner wherein the fibers are finally separated and fibrillated to form the final pulp.The refining is performed at a dry content of about 25-30%.

Abstract: A method and apparatus for use in making refiner pulp by refining lignocellulose-containing materials in a disc refiner. In accordance with the method and apparatus, the retention time of the material in a gap between a pair of refining discs is increased by diluting the refined material exiting from the gap so as to form a fiber suspension having an easily pumpable concentration and maintaining a predetermined amount of the fiber suspension adjacent to the outlet of the gap.

Abstract: A rotary grinding disc in an apparatus for refining fibrous pulp material, comprising a plurality of arcuate grinding plate segments disposed annularly about the disc and supported thereon by means of wedge-shaped tongues projecting from the segment plates and dovetailed into grooves of corresponding profile in the disc, the wedge-shaped tongues and dovetail grooves decreasing in width from an outer radial portion toward an inner radial portion, or vice versa, for wedging the plate segment into the disc. The plate segments may be additionally secured against displacement by the effect of the centrifugal force during rotation of the disc by means of a peripheral ring surrounding the disc and engaging the wedged tongues.

Abstract: Grinding apparatus in which lignocellulosic material such as wood chips is ground between a pair of grinding discs which rotate relatively to one another within a housing into which the material is advanced through a feed-in opening by means of a feed screw which rotates in a concentric sleeve extending between the central feed-in opening and an intake opening for the material. The feed screw comprises a series of inner screw flights mounted on a central shaft, which screw flights support and are enveloped by a series of outer ribbon-like screw flights. The inner screw flights are designed primarily to propel the material radially outwards towards the wall of the surrounding sleeve, whereas the outer ribbon-like screw flights are designed primarily to advance the material in an axial direction towards the central feed-in opening.

Abstract: A sealing device is provided for shafts passing through the wall of a housing containing a pressurized medium of a pressure differing from that of the environment external to the housing. The sealing device includes at least one ring of packing or sealing material formed in at least one annular layer around the outer surface of the shaft. A nonrigid sleeve is mounted around the outer surface of the ring of packing material. The sealing device further includes a duct for providing a source of pressurized medium to the outer surface of the nonrigid sleeve. The forces exerted by the pressurized medium on the outer surface of the sleeve are transmitted to the layer of packing material enclosed within the sleeve so that the packing material is maintained pressed in a close sealing relationship with the outer surface of the shaft.

Abstract: Apparatus for relieving blockage of the pulp discharge passage in a cyclone separator included in a pulping system. The pulp stock is treated in an environment of superatmospheric steam and discharged together with the steam into the separator cyclone. The separated processing steam is evacuated from the cyclone while the steam liberated pulp stock is propelled through a throat which tapers towards the discharge valve by a screw conveyor whose flights are contoured to rotate snugly within the tapered throat. The discharge valve is controlled to maintain a predetermined rate of discharge and a predetermined superatmospheric pressure within the cyclone to allow evacuation of steam therefrom. The shaft of the screw conveyor is reciprocally mounted in the cyclone to allow the screw flights to yield in response to a predetermined excessive thrust resulting from compacted pulp stock blocking the throat, to provide a by-pass between the screw flights and the throat wall and thereby relieve the blockage.

Abstract: Method and apparatus for coordinating the rate of feed and the moisture content of the pulp material to the heat quotients of the mechanical energy input in a refiner system in which the moisture-containing pulp material is introduced at an adjustable rate of feed into the central portion of an axially adjustable grinding space defined between a pair of grinding discs which rotate relative to one another within a closed housing and in which grinding space the material is propelled by centrifugal force created by the rotation of the discs in an annular radial path toward the periphery of the discs while being subjected to a grinding operation in an environment of steam generated by the heat produced by friction in the grinding space.

Abstract: Apparatus for producing pressed board and the like in a tiered multi-opening press in which the blank supporting conveyor plates are moved successively between the loading end and the discharge end along a substantially rectangular split-level track pattern in which the longer side portions are located at a level different from that of the two shorter side portions. The loaded plates are introduced into the press at the level of the side portions and at the discharge end are moved to the level of the shorter end portions and conveyed transversely to the opposite corner of the rectangular track where they are again moved to the level of the side portions and conveyed at this level to the opposite corner where in turn they are moved to the level of the shorter end portions and conveyed transversely to the opposite corner and moved to the level of the side portions where they are re-loaded and re-conveyed to the press.

Abstract: A system for measuring and regulating the grinding space between two metallic grinding discs and to prevent direct contact therebetween; one of the discs being rotated while the other one remains stationary to grind therebetween fibrous cellulosic material, such as moisture-containing wood chips, for pulp making. One of the discs is electrically insulated from the other parts of the system and is included in an electric circuit with the positive and negative terminals connected to the disc at points electrically insulated from one another and the moisture in the wood chips collected in the grinding space is used to produce a conductive cell, such as an electrolytic variable resistance, which bridges the two terminals and closes the circuit. The resistance of the cell which varies in response to fluctuations in the grinding space is measured by an ammeter or similar measuring device which thus gives a reading of the width of the grinding space.

Abstract: A pressure plate assembly for hardboard presses in which a thin metal sheet for supporting the material to be compressed into hardboard is inserted between the pressure plates. The thin metal sheet extends beyond the edges of the press plates and is bent downwardly along two opposing sides thereof to impart substantial rigidity to the overhanging portions and to provide a draining surface for the compressed material. The other two opposing edges of the metal sheet form projections having thickened reinforcement edges.

Abstract: Disclosed is a method and apparatus for pressing and binding voluminous material into bales, in which material in the form of several layers is supplied through a closable opening into a pressing chamber where compression takes place of each supplied layer. Final pressing is carried out at high pressure after a desired number of layers have been supplied into the pressing chamber, whereafter the pressing effect is lowered to a substantially lower pressure, so that the material compressed into a bale is permitted to expand, and the bale thereafter is discharged from said pressing chamber through a closable opening and bound while said substantially lower pressure is being maintained.