Abstract: A device for evacuating blow-back steam in a pulp refining apparatus in which lignocellulosic pulp stock is ground in an environment of superatmospheric steam in a grinding space defined between a pair of grinding members which rotate relatively to one another in a closed housing having a feed-in opening into which the pulp stock is advanced by means of a feed screw which rotates within a feed-in passage. A jacket having a perforate wall is arranged about the feed-in passage for receiving the blow-back steam separated from the pulp stock, and which steam is evacuated therefrom through a conduit connected to the jacket. The feed screw rotates in close proximity to the perforate wall to maintain it free of pulp stock particles.

Abstract: Method and apparatus for minimizing steam consumption in the production of pulp used for the manufacture of fiberboard and the like, in which chips of cellulosic material are ground in a defibrator or refiner in an environment of saturated steam above 100.degree. C and corresponding steam pressures. The chips are normally presteamed with atmospheric steam separated from the pulp at the discharge end of the defibrating process to a temperature between 90.degree. C and 100.degree. C and compressed and dewatered to a dryness of at least 50% and then passed into a preheater which forms part of the defibrating or refining apparatus, where the compressed and dewatered chips are heated to the desired defibrating or refining temperature, usually ranging between 130.degree. C and 200.degree.

Abstract: A disk refiner construction to be supported on a base and including first and second frame parts, said first frame part having inside a pressure proof housing attached at its periphery to said first frame part, a shaft extending into said housing and provided with a gasketing sleeve serving as a gasket for said housing, a disk attached to the end of said shaft and provided with refiner plates within the housing, and an end plate of the refiner being attached to the first frame part and provided with stationary counter plates for said refiner plates, the second frame part having inside a bearing unit for the shaft of the refiner and said first and second frame parts constituting together an uninterrupted frame having the shape of a hollow rotational body and serving as a guide and support for the shaft and its bearings, said body being further provided with fixation points positioned symmetrically in relation to the shaft for supporting the disk refiner on its base.

Abstract: A mixing and comminuting machine for the treatment of liquid-solid media and the like by compression and decompression under centrifugal action comprises an assembly including stator and rotor members which may be readily replaced as a single unit in the machine. The machine casing contains the assembly which includes a casing inset which is releasably retained in the casing and to which the stator member is stationarily secured. A wall spaced from the stator member is also secured to the casing inset for retaining the rotor member in position between the wall and the stator member such that the rotor member may freely rotate at the position when secured to rotating drive means.

Abstract: A device for controlling the rotor in a paper stock refiner to locate the rotor in a neutral position in the stator during start-up and shut-down, at which time uneven stock flow and unequal hydraulic pressures may occur tending to move the rotor off floating center so that its refiner surfaces shift toward and possibly into damaging engagement with the stator refiner surfaces. During full operation the rotor shaft is released for normal self-centering or adjustment relative to the stator.

Abstract: A grinding apparatus in which lignocellulosic material is ground between a pair of discs which rotate relatively to one another in a pressurized housing. The stock is advanced by means of a screw feeder, through a central opening in the disc housing and introduced into the grinding space between the discs under maintenance of the pressure within the housing. Excessive high-pressure steam or other gas generated during the grinding process is separated from the ground stock, which is returned to the grinding space by centrifugal force, while the steam or other gas freed of stock particles is discharged without interfering with the stock inflow.

Abstract: A method of shredding a web of material is provided. The web is moved by means of a stream of air provided by rotating impeller blades in a first path toward a shredder outlet. At least a part of the web is shredded in this path by stationary first shredding teeth and the shredded portion is immediately moved out of the outlet by the stream of air. The unshredded portion of the web is pulled from the first path into a second path and shredded as it moves in the second path by means of stationary second shredding teeth positioned at substantially a right angle to the first shredding teeth. Then this shredded part of the web is moved out of the shredder by means of the stream of air.Apparatus is provided for performing the above-described method.

Abstract: Chip-forming apparatus including housing means having a peripheral inner wall surface, a cutter cage mounted within the housing means and spaced from the peripheral inner wall surface, the cutter cage having a plurality of chip-cutting blades, means for feeding coarse material to the cutter cage to be formed into chips by the chip-cutting blades and hurled radially outwardly against the peripheral inner wall surface, and cleaning means mounted in the housing means adjacent the peripheral inner wall surface thereof and revolvable in brushing engagement with the inner wall surface.

Abstract: A centrifugal mill for disintegrating fibrous material is provided with a cylindrical grinding track in front of a conical grinding track. The grinding tracks are corrugated and are adapted to cooperate with rotary grinding blades. The corrugation of the cylindrical track is coarse compared to that of the conical grinding track. The charging port of the mill is arranged at the larger cone diameter and the discharging port for the ground stock is arranged at the smaller cone diameter. Means are provided for conducting a controlled air flow from the larger cone diameter to the smaller one through regular spaces between the rotary grinding blades in the peripheral direction thereof.

Abstract: The invention relates to a device for sealing a casing housing a machine element the rotatable shaft of which passes through the casing within which a pressure differing from that of the outside the casing is maintained. To provide a perfect sealing at the shaft passage, a liquid seal is formed by novel specific means. In a preferred embodiment where the device is combined with an apparatus the shaft of which passing through at least one wall of the casing is axially displaceable, the specific sealing means are displaceable together with the shaft while completely maintaining the sealing effect.