Abstract: An apparatus is provided for mechanical thermal dewatering of a web of fibrous material (1). The object is to provide a dewatering apparatus which delivers better drying results while precluding delamination of the web (1) of fibrous material. This is achieved in an apparatus in which the web of fibrous material is passed through at least two press surfaces (2, 3) which form a press gap and which exert the dewatering pressure on the web of fibrous material by forming one press surface (2) as an impermeable band (4) which can be pressed towards the other press surface (3) via a hydraulic pressing element means (15). A support pocket (5) is located in the pressing element essentially in the region between the web inlet end and the center of the pressing element means (15) and is effective to generate a hydrodynamic pressure field at the pressing element means (15) by setting a lubricant into circulation.

Abstract: In a headbox for a paper machine a hydraulic headbox is combined with an apertured roller headbox, with at least one movable insert part (15) through which the material suspension (5) can flow being provided in the region of the flow channel (4) and/or of the nozzle channel (18) and with the flow channel (4) having a cross section through which flow takes place which broadens over at least a substantial part of its length in the direction of flow up to the moveable insert part (15).

Abstract: A measuring bridge, fixed in place above a moving paper web and disposed crosswise to it, is provided, having a measuring head, movable back and forth--crosswise to the paper web--, for determining the measuring values for judging the thickness of the paper web at the measuring spots or point on top of which the measuring head happens to be. The measuring device, has a process management system, in which a traversing flow program has been installed, in accordance with which the traversing time and/or the reversing time of the measuring head are changed after each traverse of the measuring bridge. Because of this, the frequency of the measurements along the web becomes irregular. This prevents false evaluations of the cross section and, as a consequence, inappropriate control instructions of a control computer.

Abstract: In a deflection controlled roll (1) having a non-rotatable carrier (4), a rotatable roll jacket (7) is supported against the carrier (4) by a number of hydrostatic supporting elements (8) with adjustable pressing force. The supporting elements (8) run in corotating bearing races (9) mounted loosely in the roll jacket (7) and corotating with the roll jacket (7) but independently therefrom. These bearing races (9) are provided on both sides with flanks (15) for axial positioning, which cooperate with side bearing pockets on the supporting element (8) and form an axial guideway for the bearing race (9). Automatic positioning with maintenance of a defined bearing gap is achieved by a toroidal cross-sectional or a tapered ring-shaped construction of the running surfaces of the supporting element (8) and the bearing race (9).

Abstract: Heating or cooling roll having a roll jacket with axially running peripheral borings at the roll ends, where the borings are connected via a fixed ring shaped part which is sealed against the roll jacket, to each other and/or with the feed-in or feed-out lines of the heat carrying fluid which are mounted outside of the roll. With this simply constructed device, the feeding in and out of the heat carrying fluid is made possible, even for rolls which have a roll jacket which is shiftable in the pressure plane.

Abstract: The wet section of a twin wire papermaking machine is provided with an open forming roll at the lower wire and with the combination of a suction box at the lower wire and a vacuum suction box at the upper wire. Furthermore, by selecting the elevational position or level of the individual wire sections there can be obtained particularly advantageous conditions for the operation of the papermaking machine throughout a wide field of application, especially heavy types of paper at relatively low operating velocities of the papermaking machine. Gap-former and hybrid-former constructions of the papermaking machine are possible.

Abstract: The flotation apparatus removes ink- and contaminant particles from a fiber stock suspension which is produced during the preparation of waste paper. Admixing of air to the fiber stock suspension is accomplished in stepped diffusors. The fiber stock suspension admixed with air, prior to infeed into a flotation container, is guided through a deflection element effective as an impact mixer and followed by a mixing diffusor having a preferred flow direction. This flotation apparatus is especially suited for eliminating disturbing or spurious substances which are present throughout a relatively wide grain size spectrum. A particularly preferred construction uses one or more closed flotation containers, wherein the air effluxing from the flotation foam can be advantageously re-used for aeration of further infed fiber stock suspension.

Abstract: The apparatus for interconnecting two groups of driers of a papermaking machine serves to interconnect two successive drying sections through which successively travels a paper web which is dried by such successive drying sections. When needed or desired, such interconnection must be interrupted. For this purpose there are used additional elements which are capable of bringing about a separation of the endless drying wires associated with the respective web drying sections and, at the same time, during normal operation, that is, during the transfer of the paper web from the one to the other drying section, affording a regulatable operation capable of retaining the quality of the paper web. Thus, for this purpose there are proposed the use of adjustable rollers and also suction boxes operated under vacuum conditions.

Abstract: The invention relates to a method for roll cooling in paper machines with soft smoothing mechanisms. The object of the invention is to protect the soft roll from damage without having to increase the extent of edge trimming of the paper web. This is achieved in that the parts of the soft roll which respectively project beyond the width of the paper web are cooled by the application of a thin and sharply bounded water film. The corresponding devices for generating the water films are mounted in carriages which are displaceable along a transverse beam parallel to the roll.

Abstract: A calender for surface treatment of material webs, wherein in the event of one sided seizure of an intermediate roller the fixed roller not subject to pressure is adjusted in position at one end such that the asymmetrical linear force profile resulting from the seizure is symmetrically adjusted according to the desired condition in order to optimise processing of the material web.

Abstract: A dewatering device for the web-forming or wet section of a papermaking machine comprises foils arranged transverse to a forming wire, that is to say, extend in the cross-machine direction. Force or powering elements act upon the foils so as to exert a force or pressure upon the forming wire, and thus, bring about dewatering and sheet formation of a layer of fiber stock suspension reposing upon the forming wire. The force elements are constructed and positioned such that additional moments are generated which counteract tilting moments produced by the frictional force present between the foils and the forming wire. In certain arrangements, the force elements also can be interconnected with one another.

Abstract: A twin wire former wherein the forming turbulence of a first forming section is quieted by a main forming roller. Behind the main forming roller, as viewed with respect to a predetermined direction of travel of the forming wires, there is accomplished a further forming of the paper web or sheet from the fiber stock suspension in a second forming section. Due to this arrangement there is possible optimum formation of the paper web or sheet with the use of very little dilution water for the fiber stock suspension. Additionally, due to intensive shear forces present in the second forming section flocks formed in the fiber stock suspension and the paper web or sheet at the region of the main forming roller, can be eliminated so that the structure of the paper web or sheet is made more uniform.

Abstract: Pump-like inlet blading has operatively connected therewith a multi-stage stepped diffusor axially opening into a separation chamber. For the removal of light particles, openings or recesses are provided at the outlet side of an inner cylinder and such merge with withdrawal channels at the inner cylinder. If necessary, there are provided for the heavy particles a collecting groove at least in front of turbine-like outlet blading and from which lead openings, so-called saveall openings towards the outside. These saveall openings are briefly alternatingly opened and closed during operation of the stock suspension cleaner. The fluid stream of the cleaned stock suspension is removed by the turbine-like outlet blading. At least one part of the inner cylinder which delimits the separation chamber is separately rotatable relative to the outer cylinder, so that such inner cylinder part can be rotated at a different rotational speed than the outer cylinder.

Abstract: Heat protection hood for heated rolls (1) in particular for rapidly running rolls (1) in paper machines which are partly surrounded by the heat protection hood. In this arrangement an outer screen (7) is arranged partly around the roll (1) and is concentric to it. The outer screen (7) and a likewise concentrically extending partition screen (4) present between it and the roll (1) form an inner gap (5) and an outer gap (6). Respective deflection zones (9) for the air flow drawn along by the roll (1) in the inner gap (5) adjoin each of the ends of the partition screen (4). Deflecting units (10, 11) are provided there so as to deflect the recirculating air flow around the ends of the partition screen (4). The invention is intended to substantially reduce heat losses through radiation and convection and offers the possibility of influencing the axial temperature profile of the roll (1).

Abstract: The apparatus for the continuous winding of a web, in particular a paper web, onto a motor-driven roll core can also continue to be operated during the change of the roll core. A guiding drum serves as a support for the empty roll core during the change and is used for guiding the web. The guiding drum is continuously maintained at a distance remote from the winding. A pressing roll serves to press the web against the winding, a setting signal for a drive of a roll support carriage being derived from the position of the pressing roll, with the position changing based upon an increase in size of the winding.

Abstract: The calendering occurs in a press nip of a calender with application of pressure, moisture and heat. To achieve a desired surface quality, the surface of the paper or cardboard web which is to be calendered is brought in the press nip to a condition above the glass transition curve of the materials. Prior to expiration of 20 to 60 milliseconds, the surface of the paper web departing from the press nip is subjected to a transition step by virtue of a cooling device first in combination with a change in moisture content to a condition beneath the glass transition point of the material. The cooling can occur during contact of the surface to be cooled with a cooled surface or by direct contact with a cooling, preferably inert gas. After calendering there thus arises a diminished increase in the roughness of the paper web, so that the surface quality obtained in the press nip is predominantly retained. There have been illustrated suitable apparatuses for carrying out the method.

Abstract: In the plastic foil-producing apparatus where a fluent plastic mass is cooled in a roll nip between a roller member and a counter roller to a defined predetermined solidification temperature, the roller member includes a non-rotatable support member and a rotatable roller shell supported at the non-rotatable support member by one or more support elements. The roller shell includes a plurality of coaxial zones, namely, an inner soft rubber zone and a thin outer metallic zone possessing good thermal conductivity, for example, formed of copper or silver or alloys thereof, the outer surface of which is mirror smooth, for instance, chromium plated. The roller surface is cooled by cooling gas nozzles regulated by a temperature sensor, so that the temperature of the roller member in the roll nip assumes an exactly defined temperature.

Abstract: The invention relates to a flotation-deinking-device comprising a flotation vessel and at least one inlet for introducing the suspension into the flotation vessel, the inlet being a staged diffusor (12) in which in a region of the stage transition (26) an air inlet opening (20) is arranged. A turbulence generator (28) without an air supply is arranged upstream of the stage transition (26) as seen in the direction of flow.

Abstract: A process for manufacturing a slotted hole screen made by mechanically joining a plurality of longitudinal members to a plurality of cross bars reduces joint roughness, burrs and recesses by including a step of covering the joints with a covering material which has a smooth exterior surface. The covering material is liquefied and has sufficient surface tension to form the smooth surface. In an alternative embodiment, the joints in a slotted screen formed by welding a plurality of longitudinal members to a plurality of cross bars are smoothed by selectively remelting the joints to form the smooth exterior.

Abstract: In a calender or roll frame, apparatus is provided for the vertical adjustment of the rolls which are journalled in bearing housings (2) and also vertically displaceably connected with the roll frame (5) via sliding supports (3) and guides (4). The connection between each sliding support and the roll frame (5) takes place via a threaded spindle (7) with a nut (8) without self-locking and also via a housing (9). The nut (8) has at its inner surface (10) a toothed arrangement (11) and the housing (5) has a further toothed arrangement (13) at its inner surface confronting the toothed end face of the nut. The nut (8) and the housing (9) can be moved relative to one another by a switching piece (14) which determines whether the toothed arrangements are meshed or disengaged. In the disengaged state the rolls can move downwards under their own weight.