Abstract: A device for dewatering solid/liquid suspensions, especially pulp suspensions, where the suspension is dewatered between two belts, with one dewatering zone being a wedge zone. A pair of rolls downstream of the wedge zone impart both area pressure and line pressure on the pulp web formed by the pulp suspension.

Abstract: Device for the washing and dewatering a fibrous suspension, which device incorporates two hollow, circular cylindrical filter drums (1), which filter drums incorporate evacuation chambers inside the-filter drums for evacuation of fluid. The filter drums rotate in opposite directions to create a pinch (2) where at least one of the said filter drums (1) is installed in a trough (7,8) which partly encloses the outer surface (3) of the filter drum and which, in the direction of rotation of the filter drum, converges towards the outer surface of the filter drum. At least one pulp inflow chamber (4) is installed at the highest point (1) of one or both of the filter drums each equipped with a trough for the introduction of pulp between the outer surfaces (3) of the filter drum and its trough (7,8) for the formation of a fibrous web.

Abstract: An arrangement and method for forming a multilayered paper or paperboard web from stock suspensions containing papermaking fibers and fines, in which first and second webs are formed in first and second twin-wire forming units such that each web has a higher concentration of fines at one side than at the other side of the web. The webs are couched together such that the sides having the higher concentration of fines are in contact with each other.

Abstract: A stock feed system for a multi-layer headbox and a method in the operation of a multi-layer headbox in which into each inlet header of the multi-layer headbox, a stock concept is passed which has been produced out of the same fresh stock by adding the necessary chemicals and fillers to separated portions of the fresh stock.

Abstract: Twin wire former and method for manufacturing a fibrous material web from a fibrous suspension using same. The twin wire former comprises a movable bottom wire belt and a movable top wire belt converging at a twin wire zone. The twin wire zone has a first section, a second section and an end section. A rotating forming roller is disposed at the first section of the twin wire zone, and the to wire and the bottom wire form a wedge-shaped inlet gap at the first section of the twin wire zone. The inlet gap is adapted to receive the fibrous suspension from a headbox. The bottom wire belt and the top wire belt are adapted to form the fibrous web therebetween at the second section of the twin wire zone, and the second section of the twin wire zone has at least one drainage element. A separating device is disposed at the end of the twin wire zone and is adapted to separate one wire belt from another the wire belt.

Abstract: Device and process for applying a liquid or paste-like medium onto a traveling material web of paper or cardboard. In the application of the application medium, the material web is transferred from a first twin wire zone to a second twin wire zone. The second twin wire zone may be more finely meshed than the first twin wire zone to reduce marking and impressions in the web. The application medium may be applied and drained from one side or from both sides of the first twin wire zone or second twin wire zone. Application devices and draining (suction) devices for the application medium may oppose each other across a twin wire zone, or be arranged in alternating fashion along a twin wire zone.

Abstract: An apparatus for obtaining watermarks or patterns in paper or cardboard while being formed on a formation tape or table in a paper or cardboard manufacturing plant, comprising: a primary fibrous mix source for storing a primary fibrous mix; at least one manifold, which can be arranged proximate to the formation table; at least one jet nozzle which can be fed by the at least one manifold and is arranged above the formation table so that it can be angularly adjusted with respect thereto; a feeding duct for a secondary fibrous mix and a return duct from the at least one manifold; and a secondary fibrous mix source arranged to supply the feeding duct and to receive material discharged from the feeding duct for return from the at least one manifold.

Abstract: A wet section (10) of a paper or cardboard machine and a process for the manufacture of a fibrous material web are suggested. The wet section (10) exhibits a double-screen segment (US), in which two screens (16, 18) are guided about parallel to one another and into which a fibrous material suspension (27) is introduced. The double-screen segment (US) is looped around a roll (22). The means (30, 32, 38) for the immobilization of the fibrous material suspension in the double-screen segment (US) are provided on the roll (22), for the formation of the fibrous material web. Moreover, the wet section exhibits means (32, 34, 36; 34, 36, 66) for further draining of the fibrous material web.

Abstract: Twin-wire former for producing a fibrous material web from a fibrous suspension and process for separating upper and lower wires of the twin-wire former. The twin-wire former includes a twin-wire zone composed of a lower wire and an upper wire and a plurality of rolls including an inlet roll and an outlet roll. The upper wire is guidable over the plurality of rolls, the inlet roll guides the upper wire to the twin-wire zone, and the outlet roll guides the upper wire toward the inlet roll. A wedge-shaped inlet zone is formed between the upper wire and the lower wire and has an adjustable inlet wedge angle. An upper wire subassembly includes a drainage box adapted to receive suspension water that flows upwardly through the upper wire, and further includes a pivotable common support device, to which the drainage box and the inlet roll are mounted. A stroke device is coupled to the pivotable common support device to lift the pivotable common support device around a first horizontal axle.

Abstract: The invention refers to a process for dewatering a pulp web, particularly a chemical pulp web, where dewatering takes place between twin wire belts or felts in an initial dewatering zone with a set area pressure and then in a second dewatering zone. It is mainly characterized by the area pressure in the initial dewatering zone being pre-set, and in the second dewatering zone it is adjustable, with the web being dewatered in both directions (upwards and downwards). The invention also refers to a device for implementing the process.

Abstract: Apparatus and method for forming a continuous web on a forming fabric includes providing a pressurized chamber, processing the forming fabric through the pressurized chamber, and distributing a pressurized flow of a slurry having a first composition in the pressurized chamber across the width of the forming fabric to form the continuous web.

Abstract: In order to render a twin wire former for a paper machine more applicable to an appropriate dewatering pressure state with respect to widely used paper formation conditions, there is provided a dewatering device including a plurality of dewatering blades that face a gap for paper formation through the wires constituting closed loops. The dewatering blades comprise a pressure adjustment unit for operating the dewatering blades in a direction close to or away from a wire and an angle adjustment unit for swinging the dewatering blades in a wire running direction, which are operationally associated with each other. The angle formed between an active plane of the dewatering blades and the wires is externally adjustable by the angle adjustment unit.

Abstract: An apparatus for manufacturing a filtering medium in sheet form, comprising at least one first continuous machine, adapted for manufacturing paper and the like and suitable to form at least one first web on a first conveyor, and at least one second continuous machine also adapted for manufacturing paper and the like and suitable to form at least one second web on at least one second conveyor, the at least one second conveyor being arranged so as to make the at least one second web rest by gravity on the at least one first web, and at least one of the first and second continuous machines being suitable to form a web which is not uniformly distributed.

Abstract: In order to meet higher demands for the properties of paperboard products an improved method and machine for the manufacture of paperboard are proposed according to the present invention in which a core of a paperboard web is formed in a second forming unit from a stock with a consistency of 1.5-6.0% being supplied to the fourdrinier wire of a fourdrinier former carrying a back layer formed previously in a first forming unit, from a headbox for high consistency stock and being dewatered upon being enclosed between the fourdrinier wire and a top wire in said second forming unit, and in which an underliner is formed in a third forming unit of stock with a consistency of 0.3-1.4% being supplied to the fourdrinier wire carrying the back layer and core, from a headbox for stock of low consistency.

Abstract: A two-wire former of a papermaking making machine has the following characteristics: (1) two continuous, loop-shaped wires (1, 2) form together an inlet gap for the paper pulp suspension; (2) a sheet forming zone has a section in which both wires are guided parallel to each other; (3) a plurality of guide rollers are arranged inside and outside both wire loops; (4) a roller (3, 4) associated to each wire loop deflects the associated wire at the beginning of the parallel section; (5) at least one of both inlet rollers (3, 4) has a circumferential area that forms no closed surface (forming roller). According to the invention, (6) both wires runs on the paper pulp-bearing section in a substantially horizontal direction; (7) the top wire is separated from the bottom wire by a separating suction box (8) with a curved surface; (8) the dewatering element (7.1) that follows the forming roller on the same side of the wire is provided with elastically suspended dewatering strips (7.3).

Abstract: In order to prevent the lowering of yield of fibers of stock which is pinched by two wires and being transferred, specific dewatering blades are disposed on each of the wires are used. Blade sets are disposed on two wires 1, 2 forming loops to pinch stock 7 and running therealong. The blades of one blade set are dewatering limiting blades 20, each having a plane portion 20a to support the wires 1, 2 and an inclined face 20b disposed on the wire entering side of said plane portion 20a and forming a space of a wedge shape facing the wire face and enlarging toward the upstream side in the wire running direction. The blades of the other blade set are dewatering blades 21, each having a plane portion 21a to support the wires 1, 2 and an edge 21b to scrape water toward the upstream side of said plane portion 21a. The plane portion 21a having the edge 21b is disposed opposite to the space of a wedge shape.

Abstract: A set of ribs in a dewatering device in a paper machine for supporting and/or loading at least one wire in the paper machine and/or doctoring water from the inner face(s) of the at least one wire. The set of ribs includes at least two cross-direction ribs placed at a distance from one another in the machine direction and whose height positions are adjustable. The ribs of the set of ribs are interconnected in pairs by intermediate parts, and by crank mechanisms placed at a distance from one another in the cross direction of the at least one wire so that the ribs are loadable independently from one another.

Abstract: A twin-wire former of a paper machine, for high speed paper machines whose web running speed is of an order of from about 1600 m/min to about 2500 m/min. The former includes a carrying wire guided in a loop and a covering wire guided in a loop to define a twin-wire zone and an inlet or forming gap between the wires. A pulp suspension layer or a pulp suspension jet is fed into the inlet or forming gap through a discharge duct of a headbox. The former also includes, as a combination, a first forming-suction roll arranged proximate the forming gap in a loop of one of the wires and a second forming-suction roll arranged inside the loop of the wire opposite to the wire inside whose loop the first forming roll is arranged. The forming-suction rolls have suction zones over which the twin-wire zone is curved on certain sectors. In the suction zones, the vacuum levels are arranged adjustable independently from one another, and possibly relative to one another, so as to minimize the unequalsidedness of the web.

Abstract: A roll and blade gap former for a paper machine having first and second wires guided in a respective loop and defining a twin-wire forming zone, a forming gap in which the first and second wires converge before the twin-wire zone, a headbox including a slice channel having a slice opening through which a stock suspension jet is fed into the forming gap to form a web between the wires, and drainage and forming elements arranged in the twin-wire zone for removing water from the web. To provide an improvement in the control of the Z-direction properties of the web, the former includes turbulence generating vanes arranged in the slice channel in the headbox to cause turbulence in the stock suspension jet upon its discharge from the slice opening into the forming gap and a first forming roll arranged in the twin-wire zone and which constitutes the first drainage and forming elements in the twin-wire zone after the forming gap.

Abstract: Proposed is a method for the dewatering of a material layer (S) of paper fibers in a double-screen former, where the sheet weight (oven dried sheet weight (otro)) is more than 100 g/m.sup.2 and/or the screen circulates with a speed of at least 100 m/min. In accordance with the invention the two screens are guided at two guide surfaces (5 and 7) which, for example, belong to open forming cylinders. In this arrangement forming cylinders of this kind are so dimensioned and positioned that no dewatering elements which contact one of the screens are present between the run-out line (11) of the screens (2, 3) from the first guide surface and the run-in line (12) at the second guide surface.

Abstract: In a twin wire former a headbox injects stock onto a forming wire with which a second forming wire is brought into gradual engagement. A forming shoe directs the two wires along a path of increasing curvature, above which water is drained by adjustable auto slices. The two wires with the web therebetween then follow an oscillating S-shaped path between seven S-rolls and are directed upwardly through three individually loaded press rolls with increasing pressure to about four hundred and fifty pounds per linear inch at the last wet press. Drainage pans collect water from the upper surface of the twin wires and water thrown off the upper press rolls. The press rolls are individually pneumatically pivotable to increase nip pressure, and collectively pivotable to open all the nips. Next a high pressure dry nip can increase the fiber content of the web to thirty-five percent fiber.

Abstract: A twin-wire gap former in a paper machine in which an outer wire and an inner wire are guided by guide rolls and by web forming members. The wires form a twin-wire zone which starts from a forming gap into which a slice part of a headbox feeds a stock suspension jet. The forming gap is followed by a curved portion of the twin-wire zone which is guided by a first forming roll placed inside the loop of one of the wires. The forming-gap arrangement includes two opposite tip plates which define a slice channel between them. The lip plates extend deep into the forming gap so that the free ends of the lip plates are placed in direct vicinity of the forming wires or in contact with the wires. On the curve sector of the twin-wire zone, which starts after the forming gap and which is guided by the first forming roll, inside the loop of one of the wires, a water drainage box is provided, at which box the edges of the sides that are placed against the inner face to the wire are substantially sealed.

Abstract: A former section provided with a twin-wire zone in a paper machine including a carrying wire and a covering wire which form the twin-wire zone therebetween them, and web-forming and draining members arranged in the twin-wire zone. In an initial part of the twin-wire zone, a stationary unit of forming ribs is arranged inside a loop of one of the wires and includes transverse forming ribs extending across the entire width of the wires and placed at a distance from one another to define gaps therebetween. A loading unit is placed opposite to these forming ribs inside the loop of the opposite wire and includes spring blades which are loaded against that wire. The dragging and loading areas of these spring blades are placed substantially in the middle areas of the gaps between the forming ribs in the stationary unit of forming ribs to prevent crushing of the web between the forming ribs in the stationary unit of forming ribs.

Abstract: A stock feed system for a multi-layer headbox in which a stock concept is passed into each inlet header in the multi-layer headbox. The stock concepts are produced out of the same fresh stock by adding chemicals and fillers to divided portions of that fresh stock. To this end, the system includes a single fresh-stock container, and stock lines into which the fillers, additives and equivalent are added in compliance with the requirements of each concept. The stock feed system also includes at least one fiber distributor for transferring long fibers out of the stock that is destined to form the surface layer of the paper into the stock that is destined to form a layer placed in the interior of the paper, preferably the middle layer.

Abstract: A forming section for a two-fabric paper machine using at least one formation blade having a shallow cavity in its top surface. The cavity is placed and dimensioned to withdraw fluid continuously from the stock, and to propel it back through the fabric and the incipient paper web into the stock so as to cause a controlled level of localized turbulence which serves to improve formation without causing excessive drainage or fines loss. The formation blade shape, in conjunction with the forming fabric tension, is configured to provide a hydraulic seal between the fabric and the stock, so that all of the withdrawn fluid is returned to the stock.

Abstract: In a twin-wire former for the production of a paper web, two wire belts (11 and 12) together form a twin-wire zone which is divided into three sections (I, II and III). In the first section (I) the two wires (11, 12) travel over a curved forming shoe (16), or a forming roll (40). They form there a wedge-shaped inlet slot (15) with which a headbox (10) is directly associated. In the second section (II), several resiliently supported strips (27) rest against the lower wire (11) and between each of said strips (27) a rigidly mounted strip (28) rests against the upper wire (12). In the third section (III) both wire belts (11, 12) pass over another curved forming shoe (23).

Abstract: A set of ribs in a dewatering device in a paper machine which is used to support and/or to load the wire or wires in the paper machine and/or to doctor water from an inner face of a loop of the wire or wires. The set of ribs includes at least two transverse ribs placed one after the other at a distance from one another in the machine direction. The height positions of the ribs are adjustable and the ribs are interconnected in pairs by intermediate parts. The intermediate parts connect to the ribs by mechanisms of four articulated joints placed at a distance from one another in the transverse direction of the wire/wires so that the positions of the ribs in the horizontal direction remaining invariable irrespective of the height positions of the ribs in relation to one another. The intermediate parts and associated articulation mechanism are placed at a distance from one another in the vertical direction.

Abstract: A method and device in the regulation of a headbox. The headbox includes a pulp inlet header, after the pulp inlet header, seen in the pulp flow direction, a distributor manifold whose pipes are opened into an intermediate chamber. The headbox comprises an attenuation chamber placed in connection with the intermediate chamber and, after the intermediate chamber, a turbulence generator having tubes which are opened, at their outlet end, into a discharge duct and, at their inlet end, into the intermediate chamber. In the method, into different positions along the width of the headbox, a pulp suspension flow is introduced, the concentration of this flow is adjustable by combining two component flows. In the method, in the regulation of the concentration of the flow passed into the pulp suspension, two component flows are combined by into the pulp suspension flow introducing an additional flow. The mixing ratio of the combined flow is regulated by adjusting the additional component flow.

Abstract: A hybrid former in a paper machine including a lower-wire loop in which there is an initial single-wire portion of a forming zone. In this initial portion, there are draining elements inside the lower-wire loop and thereafter wire-guide and draining elements. The former includes an upper-wire unit in which an upper wire is guided by guide rolls and by a breast roll onto a pulp layer formed on the single-wire portion of the lower wire. In a subsequent twin-wire portion following the single-wire portion, there is a draining and forming unit which includes at least one pressure-loaded press unit and at least one draining-chamber and support unit, which units are arranged inside opposite wire loops. In the units, there are sets of ribs which are pressure-loaded against each other.

Abstract: A wire part of a machine for the production of continuous fibrous material webs, especially a papermaking machine, includes two continuous wire belts which together form a twin-wire zone. At least one supporting element having a supporting surface is disposed in the region of the twin-wire zone. At least a part of the supporting surface provides a supporting region which supports a first wire belt on its inner surface and a second wire belt on its outer surface. At least one formation box is provided and is disposed in the supporting region. The formation box is designed in such a way that, in the region of the inner surface of the second wire belt in the formation box, pressure values can be adjusted from a reduced pressure to an excess pressure acting on the inner surface of the second wire belt. The formation box extends in the direction of movement of the wire part over at least a part of the supporting region.

Abstract: In a method for forming a sheet from a fiber-water suspension, the fiber-water suspension is supplied on a traveling bottom wire at a first zone thereof to dewater the fiber-water suspension. Subsequently, the suspension is introduced between the bottom wire at a second zone and a top wire, and dewatering is effected. The sheet is further caused to travel around a sheet-forming roll while keeping the sheet in contact therewith by the bottom wire at a third zone thereof, and reformation of the sheet is carried out. Finally, the sheet on the bottom wire is caused to travel up to a fourth zone thereof to effect a further dewatering with a fourth dewatering device disposed adjacent to the bottom wire at the fourth zone thereof, whereby a final stage of sheet formation is carried out. An apparatus for carrying out the above method is also disclosed.

Abstract: In a double wire former of a paper machine, a first continuous wire (1) is fed onto an at least partially curved guiding surface (4) so as to converge with a second wire (2), wherein the guiding surface (4) is movable in a form-locked manner relative to the wires. After the dewatering section described above, a further guiding surface (7) follows which, in advantageous embodiments, has an opposite sense of curvature and is fixedly located.

Abstract: A loading box adjustable in zones thereof for a former of a paper or board machine. The former comprises a twin-wire section including two wires placed one above the other and running in the same transfer direction. In the twin-wire section, a drain box is mounted at one side of the wires to remove water out of a fibrous pulp running between the wires. At the opposite side of the wires, a loading box is mounted and is provided with loading ribs arranged in the transverse direction in relation to the transfer direction and which extend across the web width. The loading ribs are loaded toward the bottom of the drain box in order to produce a desired compression in the fibrous pulp running between the wires. The loading box is provided with loading members arranged to produce a locally raising or lowering force applied to the loading ribs in the direction transverse to the transfer direction.

Abstract: The invention is related to a twin-wire web former in a paper machine having a covering wire and a carrying wire which form a twin-wire forming zone with one another. A discharge opening of a headbox feeds a pulp suspension jet into the forming gap defined between said wires. The forming gap is immediately followed immediately by a forming shoe provided with a curved guide deck. A draining unit or units is/are provided after the forming shoe, before the first forming roll. The draining unit/units comprise(s) a press/support unit which guides the wire placed in contact with it as a straight run. The draining unit or units further comprise(s) a draining equipment provided with suction and foil equipment and placed opposite to the press/support unit, which draining equipment removes a substantial amount of water out of the web.

Abstract: A hybrid former in a paper machine including a lower-wire loop in which there is an initial single-wire portion of a forming zone. In this initial portion, there are draining elements inside the lower-wire loop and thereafter wire-guide and draining elements. The former includes an upper-wire unit in which an upper wire is guided by guide rolls and by a breast roll onto a pulp layer formed on the single-wire portion of the lower wire. In a subsequent twin-wire portion following the single-wire portion, there is a draining and forming unit which includes at least one pressure-loaded press unit and at least one draining-chamber and support unit, which units are arranged inside opposite wire loops. In the units, there are sets of ribs which are pressure-loaded against each other.

Abstract: The invention relates to a twin-wire web former for a paper machine wherein a covering wire and a carrying wire form a twin-wire forming zone between them. A method for dewatering a web is also disclosed. In the invention, water is drained out of a web running through the twin-wire zone through both of the wires. After the twin-wire zone, the web is separated from the covering wire and is transferred on the carrying wire to a pick-up point. In hybrid formers, after an initial single-wire forming zone preceding the twin-wire zone, and in gap formers, after a curved forming zone placed directly after a forming gap, there is a forming shoe provided with a ribbed deck and arranged inside one of the wire loops. This forming shoe is followed by dewatering and web forming units which include forming ribs and are placed inside both of the wire loops. At least one of the dewatering and web forming units is loaded by means of a pressure-hose arrangement.

Abstract: A twin wire former of a paper machine can perform dewatering gently and symmetrically on the front and back sides of the wet paper, thereby producing paper with good yield and excellent front/back similarity. The twin wire former includes the loops of two wires, and first, second and third dewaterers, having large radii of curvature and disposed inside one and the other of the loops of the wires sequentially alternately between a point where a raw material jet alights on the wires and a couch roll, and the wire-run over this section is diagonal. The first and third dewaterers are disposed inside the loop of the wire and the second dewaterer is disposed inside the loop of the wire. This second dewaterer is pivotable about a point in the vicinity of its rear end, and the couch roll is a solid roll. This couch roll, a transfer suction box and the third dewaterer are mounted on a swing arm and can be pivoted for wire installation.

Abstract: A twin-wire web former in a paper machine, having a single-wire initial portion, after which a twin-wire zone starts in the area of a ribbed deck of a first forming shoe placed inside one of the wire loops. After the first forming shoe, a pressure-loaded dewatering unit is arranged and which includes opposite sets of ribs and dewatering chambers. A first dewatering chamber in the dewatering unit is placed above the first forming shoe so as to remove water that drains from the area of the curved ribbed deck of the first forming shoe through its suction-deflector duct. The first dewatering chamber is followed by a second dewatering chamber, whose lower part is connected with a set of dewatering and guide ribs having gap spaces into which a drain duct of the second dewatering chamber opens. Against the set of dewatering and guide ribs, a set of loading ribs operates, which is placed inside the opposite wire loop and which operates by means of the medium pressure of loading hoses.

Abstract: A wire section of a machine for making a fiber web, with two continuous wires forming together a twin-wire zone. A dewatering element is pressable on the inside of the wire with at least one surface. The dewatering element features in the direction of travel of the fiber suspension, in interaction with the wires, two dewatering zones. The first dewatering zone is defined by an essentially flat surface, while a second dewatering zone is defined by a surface curving about an axis of curvature in the direction of travel of the fiber suspension. Coordinated with the dewatering element are at least two support axes on which support elements are arranged. Coordinated with the dewatering element is a pivot axis. The pivot axis is stationary as regards the tilting operation, and extends parallel to the separation plane between the first and second dewatering zones and parallel to the wire. The pivot axis is arranged in the area of the axis of curvature.

Abstract: A method and device in the regulation of a headbox. The headbox includes a pulp inlet header, after the pulp inlet header, seen in the pulp flow direction, a distributor manifold whose pipes are opened into an intermediate chamber. The headbox comprises an attenuation chamber placed in connection with the intermediate chamber and, after the intermediate chamber, a turbulence generator having tubes which are opened, at their outlet end, into a discharge duct and, at their inlet end, into the intermediate chamber. In the method, into different positions along the width of the headbox, a pulp suspension flow is introduced, the concentration of this flow is adjustable by combining two component flows. In the method, in the regulation of the concentration of the flow passed into the pulp suspension, two component flows are combined by into the pulp suspension flow introducing an additional flow. The mixing ratio of the combined flow is regulated by adjusting the additional component flow.

Abstract: The invention relates to a twin-wire web former for a paper machine wherein a covering wire and a carrying wire form a twin-wire forming zone between them. A method for dewatering a web is also disclosed. In the invention, water is drained out of a web running through the twin-wire zone through both of the wires. After the twin-wire zone, the web is separated from the covering wire and is transferred on the carrying wire to a pick-up point. In hybrid formers, after an initial single-wire forming zone preceding the twin-wire zone, and in gap formers, after a curved forming zone placed directly after a forming gap, there is a forming shoe provided with a ribbed deck and arranged inside one of the wire loops. This forming shoe is followed by dewatering and web forming units which include forming ribs and are placed inside both of the wire loops. At least one of the dewatering and web forming units is loaded by means of a pressure-hose arrangement.

Abstract: The twin-wire former serves for the production of a web of paper or board. Two wire belts (endless wire loops 11 and 12) form a twin-wire zone with each other. Within the twin-wire zone, the one wire belt (12) travels over rigid ledges (28', 28) which are arranged spaced apart from each other on a water-removal box (18). Within the twin-wire zone, furthermore, the other wire belt (11) travels over several ledges (27) which lie opposite the rigid ledges (28), are supported by means of resilient elements (springs 24, pneumatic pressure cushions, or the like), and can be pressed with a selectable force against the other wire belt. Within one of the wire loops (for instance 11), bridging at least two of the ledges (27) present there, a closed wire support surface (9) is provided. A secondary headbox (10') can be arranged in front of the closed wire support surface (9).

Abstract: In a twin-wire former for the production of a paper web, two wire belts (11 and 12) together form a twin-wire zone which is divided into three sections (I, II and III). In the first section (I) the two wires (11, 12) travel over a curved forming shoe (16). They form there a wedge-shaped inlet slot (15) with which a headbox (10) is directly associated. In the second section (II), several resiliently supported strips (27) rest against the lower wire (11) and between each of said strips (27) a rigidly mounted strip (28) rests against the upper wire (12). In the third section (III) both wire belts (11, 12) pass over another curved forming shoe (23).

Abstract: A twin-wire former for a paper machine having two endless loop wires, a wire support frame and a head box. The web forming zone leading from the entrance slot, which is at the breast roll in one wire loop and the forming roll in the other wire loop, is inclined at an angle of 30.degree. to 50.degree. to the horizontal. The wire support frame has the shape of an inverted U with a front support arranged upstream of the head box, a rear support arranged downstream of the headbox and an upper beam which connects the upper ends of the front and rear supports to each other. A lower beam is located within the loop of the lower wire and extends to both of the forward and rearward sides of the rear support with one end extending into the U-shaped frame while the other end extends at least approximately up to the remote end of the loop of the lower wire. At least one water removal element of the upper wire is suspended from the upper beam. At least one water removal element of the lower wire rests on the lower beam.

Abstract: The wire end or forming section of a paper making machine is a twin wire section defined by two endless loop wire belts or wires between which fibrous suspension moves through the wire end. A supporting element, either in the form of a rotating cylinder or in the form of a support belt, has the wires passing over it in the twin wire zone. Pressure elements, in the form of strips, rods or even a shoe, are supported to apply pressure on the wire belts and directed toward the moving supporting surface. The pressure elements are placed along the twin wire path so that pressure free regions remain between neighboring pressure elements. The pressure elements are distributed over the entire width of the wire belts.

Abstract: A self-loading controlled deflection roll has movable shoes disposed inside the roll shell, at the opposite ends and at the center of a central shaft, for displacing the external surface of the roll shell toward and away from a mating roll forming a nip with the controlled deflection roll. In order to ensure that both ends of the controlled deflection roll shell move evenly in a radial direction into nipping engagement with the mating roll, and to also ensure that the ends retract evenly away from nip engagement, a control system and method are provided for automatically adjusting the flow of hydraulic fluid, such as oil, which is used to displace the shoes at the opposite end of the central shaft.

Abstract: A wire or felt forming section of a paper-making machine has breast rollers for guiding a respective one of two forming wires. The two rollers are disposed with a pulp gap formed between the two rollers and the wires are disposed just downstream of a pulp suspension ejecting nozzle of a headbox. Each roller is supported against the respective taut forming wire by a hydrostatic bearing. The hydrostatic bearing has two circumferentially separated resiliency chambers provided in a combined region of resiliency disposed over an arc of the circumference of the roller. A sealing strip after the region of resiliency prevents fluid from contacting the wire.

Abstract: A suction roll for a paper machine in which a stationary suction shoe is arranged inside a revolving mantle loop and is connected to a source of negative pressure. The mantle loop is a substantially water-receiving and permeable fabric-sock loop that receives water and is, in a preferred embodiment, supported by means of guide members arranged inside the loop. The suction shoe is provided with a permeable guide deck against which the inner face of the fabric-sock loop glides.

Abstract: In a twin-wire former for the production of a paper web, two wire belts (11 and 12) together form a twin-wire zone which is divided into three sections (I, II and III). In the first section (I) the two wires (11, 12) travel over a curved forming shoe (16). They form there a wedge-shaped inlet slot (15) with which a headbox (10) is directly associated. In the second section (II), several resiliently supported strips (27) rest against the lower wire (11) and between each of said strips (27) a rigidly mounted strip (28) rests against the upper wire (12). In the third section (III) both wire belts (11, 12) pass over another curved forming shoe (23).

Abstract: In a Fourdrinier paper making system where all of the water from the stock slurry is removed in one direction downwardly through the paper web, a sheet forming unit, including two spaced dandy rolls with a pocket roll inbetween, is added to press a secondary fabric downwardly on the top surface of the paper web. The pocket roll cooperates with a suction box below the paper web to remove water while the web passes over a low vacuum section and then over a high vacuum section and then over a low vacuum section of the suction box. This treatment produces a better internal bond between the fibers in the paper web and also produces better surface properties.