Abstract: An apparatus and process for depositing slurry upon a moving forming web. The apparatus includes a pivotally mounted headbox for depositing slurry from the inner bottom surface of the headbox down an inclined spillway as a continuous curtain onto a moving web. The headbox is mounted transverse to the direction of travel of the moving web. The headbox also has vertical edge boards, including a headbox back edge board and two opposed headbox side edgeboards, on three respective sides of the headbox to prevent slurry from spilling over the sides and back of the headbox. The headbox is supplied with slurry from a slurry mixer by a feed line mounted on a reciprocating trolley which moves, transverse to the direction of travel of the moving web, back and forth along the length of the headbox.

Abstract: A headbox is provided that comprises at least one first inlet channel adapted to receive furnish comprising fibres, at least one turbulence generator connected to the first inlet channel, a second inlet channel adapted to receive a non-fibrous high consistency composition, and a sliced cone connected to the turbulence generator and the second inlet channel. The first inlet channel and the turbulence generator are arranged so that the furnish is passed through the first inlet channel and further to the turbulence generator and thereafter to the sliced cone. The second inlet channel is arranged so that the non-fibrous high consistency composition is passed through the second inlet channel and directly to the sliced cone bypassing the turbulence generator.

Abstract: A sheet forming unit including a headbox with at least one feed device, a turbulence generating device having a plurality of turbulence generating channels and a nozzle. The nozzle includes an outlet gap located downstream from the headbox forming a line of impingement in a flow direction. Immediately upstream from the nozzle is the turbulence generating device in which during operation of the headbox a fibrous stock suspension passes through the plurality of turbulence generating channels in partial flows. Inside a turbulence generating channel there is a final fluidization region in which a pressure loss is produced in the partial flow of fibrous stock suspension in the turbulence generating channel. The headbox and the forming unit are arranged so that a dwell time of the fibrous stock suspension from the final fluidization region to the line of impingement on the clothing is ?30 ms to ?300 ms.

Abstract: A headbox for a machine for producing a fibrous material web, in particular a paper or cardboard web, includes: a central assembly preferably forming the carrier elements of a turbulence generator, said assembly having a table leaf on the bottom side; and a headbox nozzle adjoining directly downstream in the machine running direction and extending in the machine transverse direction, said nozzle comprising at least one lower and one upper continuous nozzle wall extending over the machine width. The lower nozzle wall of the headbox nozzle of the headbox includes a lower lip plate, in particular a lower lip carrier plate, which is connected, in particular welded, to the table leaf of the central assembly by means of ribs extending in the machine running direction and spaced apart in the machine transverse direction. The ribs are designed in an elastic or pliable manner in the machine transverse direction.

Abstract: A method for operating a sheet-forming unit of a papermaking machine. At least one fibrous material suspension is fed to a headbox and is conducted in a plurality of turbulence-generating channels to form sub-flows, and fed to a nozzle. From the nozzle, the at least one fibrous material suspension is in the form of a free jet into the forming unit to define an impingement line. In a final fluidization region of an individual turbulence-generating channel a pressure loss (?p) of ?50 mbar is generated within the fibrous material suspension before inlet thereof into the nozzle, and the fibrous material suspension is guided from the final fluidization region as far as the impingement line in such a way that the dwell time of the suspension in the region defined by the final fluidization region as far as the impingement line ranges from >30 ms to ?300 ms.

Abstract: A sheet-forming system includes a separating wedge with a separating wedge protrusion in a range of 0.05 to 3.0 of the largest single gap width of at least two nozzle chambers. The separating wedge includes two separating wedge areas, each having one separating wedge angle, an upstream separating wedge starting area and a downstream separating wedge ending area. The two separating wedge angles assume different angles. The separating wedge starting angle of the upstream separating wedge initial area assumes a greater angle than the separating wedge ending angle of the downstream separating wedge end area. At least one separating wedge surface is a nonplanar transitional area between the two separating wedge areas. The fibrous material suspension free jet formed from at least two fibrous material suspension streams has a free jet length of 100 to 500 mm. The forming roll has a diameter of 1,200 to 2,500 mm.

Abstract: A headbox includes a feed device for feeding at least one fiber suspension, a perforated distribution pipe plate arranged immediately downstream thereof and having a plurality of channels arranged in lines and columns and an intermediate channel arranged downstream thereof extending over the width of the headbox and having a plurality of apparatuses for dosing a fluid in partial fluid streams to the at least one fiber suspension in an adjustable/controlled manner. The apparatuses are spaced apart from each other in the width direction of the headbox and the individual apparatuses include a plurality of dosing channels having respective dosing channel openings on the outlet side and a dosing channel length, arriving at different levels and being connected to a common supply channel.

Abstract: The invention relates to a headbox for a machine for producing a fibrous web, in particular a paper or cardboard web, from at least one fibrous stock suspension, having a feed apparatus which feeds the at least one fibrous stock suspension, having a distributor-pipe perforated plate which is adjacent downstream and has a multiplicity of channels which are arranged in rows and in columns, having an intermediate channel which lies downstream of the latter, extends over the width of the headbox and has a plurality of means which are spaced apart from one another in the width direction of the headbox for the preferably regulatable/controllable metering of a fluid in fluid part streams into the at least one fibrous stock suspension.

Abstract: The invention relates to a headbox which comprises a feed device feeding the at least one fiber suspension, a perforated distribution pipe plate arranged immediately downstream thereof and having a plurality of channels arranged in lines and columns, an intermediate channel arranged downstream thereof, extending over the width of the headbox and having a plurality of means for dosing a fluid in partial fluid streams to the at least one fiber suspension in a preferably adjustable/controlled manner, the means being spaced apart from each other in the width direction of the headbox and the individual means comprising a plurality of dosing channels having respective dosing channel openings and an opening center line, arriving at different levels and being connected to a common supply channel.

Abstract: A method for operating a sheet-forming unit of a papermaking machine. At least one fibrous material suspension is fed to a headbox and is conducted in a plurality of turbulence-generating channels to form sub-flows, and fed to a nozzle. From the nozzle, the at least one fibrous material suspension is in the form of a free jet into the forming unit to define an impingement line. In a final fluidization region of an individual turbulence-generating channel a pressure loss (?p) of ?50 mbar is generated within the fibrous material suspension before inlet thereof into the nozzle, and the fibrous material suspension is guided from the final fluidization region as far as the impingement line in such a way that the dwell time of the suspension in the region defined by the final fluidization region as far as the impingement line ranges from >30 ms to ?300 ms.

Abstract: A headbox includes a feed device feeding the fibrous material suspension, a nozzle, and a turbulence-generating device. The fibrous material suspension is guided in the turbulence-generating device in sub-flows through turbulence-generating channels. Within the individual turbulence-generating channel of the turbulence-generating device, at least one region forming a fluidization region is provided, in which a pressure loss can be generated in the sub-flow of the fibrous material suspension guided through said region. The nozzle and the turbulence-generating device are designed and dimensioned such that they are suitable for setting a dwell time of ?200 ms of the fibrous material suspension flowing through the same from a final fluidization region of an individual turbulence-generating channel before inlet into the nozzle as far as the outlet gap of the nozzle, and a pressure loss of ?50 mbar in the final fluidization region upstream of the inlet into the nozzle.

Abstract: The invention relates to a headbox for a machine for producing a fibrous web, especially a paper or cardboard web, from at least one fiber suspension, comprising a feed device feeding the at least one fiber suspension, a perforated distribution pipe plate arranged immediately downstream thereof and having a plurality of channels arranged in lines and columns, an intermediate channel arranged downstream thereof, extending over the width of the headbox and having a plurality of means for dosing a fluid in partial fluid streams to the at least one fiber suspension in a preferably adjustable/controlled manner, the means being spaced apart from each other in the width direction of the headbox and the individual means comprising a plurality of dosing channels having respective dosing channel openings on the outlet side and a dosing channel length, arriving at different levels and being connected to a common supply channel.

Abstract: A headbox for a machine for producing a fibrous web, in particular a paper, cardboard or tissue web from at least one fibrous stock suspension, includes a feeding device for feeding the at least one fibrous stock suspension; a perforated distribution pipe plate which is arranged immediately downstream from the feeding device in the flow direction of the at least one fibrous stock suspension and which includes a plurality of flow channels arranged in rows and columns; an intermediate channel which is arranged immediately downstream from the perforated distribution pipe plate in the flow direction of the at least one fibrous stock suspension and which extends in a width direction of the headbox and includes two walls, for example having the width of the machine; a turbulence generator which is arranged immediately downstream of the intermediate channel in the flow direction of the at least one fibrous stock suspension and which has a plurality of flow channels arranged in rows and columns; and a headbox nozzle

Abstract: A headbox includes a feed device for feeding at least one fiber suspension, a perforated distribution pipe plate arranged immediately downstream thereof and having a plurality of channels arranged in lines and columns and an intermediate channel arranged downstream thereof extending over the width of the headbox and having a plurality of apparatuses for dosing a fluid in partial fluid streams to the at least one fiber suspension in an adjustable/controlled manner. The apparatuses are spaced apart from each other in the width direction of the headbox and the individual apparatuses include a plurality of dosing channels having respective dosing channel openings on the outlet side and a dosing channel length, arriving at different levels and being connected to a common supply channel.

Abstract: The present invention relates to a process for producing a paper or paperboard product which process comprises the steps of providing a first headbox with a furnish comprising fibres, which furnish forms at least one layer of the paper or paperboard product, providing the headbox with a non-fibrous high consistency composition, which composition forms at least one additional layer of the paper or paperboard product and conducting the layers onto a wire forming a multilayer web which is further dewatered and dried forming the paper or paperboard product. The invention further relates to a paper or paperboard produced according to the process and a headbox used in the process.

Abstract: The invention relates to a headbox for a machine for producing a fibrous web, especially a paper or cardboard web, from at least one fiber suspension, comprising a feed device feeding the at least one fiber suspension, a perforated distribution pipe plate arranged immediately downstream thereof and having a plurality of channels arranged in lines and columns, an intermediate channel arranged downstream thereof, extending over the width of the headbox and having a plurality of means for dosing a fluid in partial fluid streams to the at least one fiber suspension in a preferably adjustable/controlled manner, the means being spaced apart from each other in the width direction of the headbox and the individual means comprising a plurality of dosing channels having respective dosing channel openings on the outlet side and a dosing channel length, arriving at different levels and being connected to a common supply channel.

Abstract: The invention relates to a headbox for a machine for producing a fibrous web, in particular a paper or cardboard web, from at least one fibrous stock suspension, having a feed apparatus which feeds the at least one fibrous stock suspension, having a distributor-pipe perforated plate which is adjacent downstream and has a multiplicity of channels which are arranged in rows and in columns, having an intermediate channel which lies downstream of the latter, extends over the width of the headbox and has a plurality of means which are spaced apart from one another in the width direction of the headbox for the preferably regulatable/controllable metering of a fluid in fluid part streams into the at least one fibrous stock suspension.

Abstract: The invention relates to a headbox which comprises a feed device feeding the at least one fiber suspension, a perforated distribution pipe plate arranged immediately downstream thereof and having a plurality of channels arranged in lines and columns, an intermediate channel arranged downstream thereof, extending over the width of the headbox and having a plurality of means for dosing a fluid in partial fluid streams to the at least one fiber suspension in a preferably adjustable/controlled manner, the means being spaced apart from each other in the width direction of the headbox and the individual means comprising a plurality of dosing channels having respective dosing channel openings and an opening center line, arriving at different levels and being connected to a common supply channel.

Abstract: A head-box for depositing slurry upon a moving web including a main metering roll, a companion roll disposed in closely spaced relation to the metering roll and a vibrating gate which forms a nip between the metering roller and the gate. The nip is arranged to retain a supply of the slurry, and the rolls are driven so slurry retained in the nip progresses over an upper outer peripheral surface of the metering roll to be deposited upon the web. Also, preferably included is a doctor blade disposed in operational relationship to the metering roll for directing the slurry downwardly from the outer metering roll surface to a point above the surface of a carrier for a fiberglass layer upon which the slurry layer is deposited. The vibrating gate and doctor blade may be pivotally mounted to either side of the surfaces of the head-box.

Abstract: Machine for the production/processing of a material web, in particular a fibrous web, for example of paper or board, which comprises at least one treatment section in which the material web can have a treatment fluid applied to it, the treatment section being connected or able to be connected to a treatment fluid source via at least one line connection, an elastically deformable compensating material arranged in a fluid holding chamber of the treatment fluid source or of the treatment section. Alternatively, a damping device may be connected to the line connection or arranged in the latter and/or delimits such a fluid holding chamber, and/or elastically deformable compensating material which, in at least one section of the line connection, defines or co-defines an effective line cross section.

Abstract: A headbox, for example, in a pulp or board machine, is suitable for high basis weights which are over 400 g/m2 and for high fiber suspension consistencies which are in a range of 2–5%. The headbox has a turbulence part (1), into which a fiber suspension flows from a tube bank (2), and a slice part (3) which is situated after the turbulence part and from which the fiber suspension flows to a forming section of a fibrous web. The turbulence part (1) of the headbox has at least two passages (5, 6), which converge in the flow direction of the fiber suspension towards the slice part (3). In that connection, the fiber suspension flow is first fluidized in a tortuous turbulence passage part (11) and, after that, it decelerates in another widening deceleration passage (12).

Abstract: A headbox for use in a water felting process includes a housing and two rotating horizontal distribution rolls. The housing has curved sections shaped to conform to the outer cylindrical surface of the distribution rolls, wherein the curved section is closely spaced to a portion of the outer cylindrical surface of both distribution rolls.

Abstract: This invention relates to an improvement in coatings particularly suited for the preparation of paper products having an ink jet coating applied thereto and to the resulting paper products. The improvement in ink jet coatings resides in the incorporation of a primary amine functional polyvinyl alcohol (PVOH/PVNH2) as a polymeric binder. One form of an amine functional polyvinyl alcohol is produced by the hydrolysis of a copolymer of vinyl acetate and N-vinylformamide or vinyl acetate and allyl amine. Another is the polyvinyl butyral derivative of polyvinyl alcohol which typically is formed by the reaction of a 4-amino alkyl aldehyde dialkyl acetal, such as 4-aminobutyraldehyde dimethyl acetal with polyvinyl alcohol.

Abstract: A headbox for use in a water felting process includes a housing and two rotating horizontal distribution rolls. The housing has curved sections shaped to conform to the outer cylindrical surface of the distribution rolls, wherein the curved section is closely spaced to a portion of the outer cylindrical surface of both distribution rolls.

Abstract: Headbox that includes a turbulence generator including a plurality of essentially parallel rows of pipes and a jet including of an upper lip and a lower lip arranged to form a jet space and a jet outlet slit. A plurality of lamellae are arranged to subdivide the jet space, and the plurality of lamellae include end sections and lamella sections. The end sections are mounted between the plurality of essentially parallel rows of pipes, and at least some of the lamella sections are arranged to converge over a bend point in a direction of the jet outlet slit and, thereby, are angled toward a longitudinal axis of the turbulence generator.

Abstract: A paper-making machine for making a paper web from a fiber suspension includes a headbox having a plurality of walls defining a chamber, and an inlet connected to at least one of the walls and disposed in fluid communication with the chamber. The inlet is configured to receive the fiber suspension. The headbox also has a discharge nozzle disposed in fluid communication with the chamber. The discharge nozzle defines an outlet from which the fiber suspension is discharged. The headbox also includes a sonic transducer, associated with the discharge nozzle, for transmitting sonic energy into the fiber suspension within the discharge nozzle and thereby substantially deflocculating the fiber suspension within the discharge nozzle.

Abstract: Device for the formation of a fan jet (J) of liquid, of the type comprising:means (3) for supplying a liquid;means for distributing the delivery and for controlling the turbulence of the liquid supplied;outlet means (4) for the fan jet (J) formed, characterized in that the means for distributing the delivery and for controlling the turbulence of the liquid supplied are formed:from a first fixed curved conduit (15) for the flow of the liquid;from a second curved conduit (25) having an axis parallel to that of the first conduit (15);from means (26) for forming calibrated vortices having an axis parallel to the curved flow, so as to bring about a harmonic transverse distribution of the speeds and pressures and to control the scale and level of the vortices.Planned uses: headbox of a paper machine or installation for the couching of paper.

Abstract: A papermaking machine is constructed as a barrier former in which a fiber slurry is received and placed in turbulence on one side of the screen plate for fluidizing the slurry and distributed through the screen plate onto a collecting wire, under tension, for immediately starting dewatering of a web formed in a wedge-shaped forming zone between the screen plate and the wire.

Abstract: A single- or a multi-layer headbox of a paper or a board machine intended for consistencies of 0.7-2.2% and provided with a flow ratio adjustment device. The adjustment device operates by removing a part of the stock flow from the slice chamber out of the headbox in a manner that does not change the speed or turbulence of the flow going to the slice at any point of the headbox.

Abstract: Method and device in a head box of a paper machine for controlling distribution of fiber orientation in a paper web in a transverse direction of the machine. In the method, the transverse speed component of a discharge jet is controlled by regulating alignment of turbulence pipes in a pipe battery of a turbulence generator in the head box. In the device of the invention, a perforated plate in the turbulence generator is provided with a heating arrangement, by which the temperature level of the perforated plate and thereby the length thereof and angle of alignment of the turbulence pipes attached to the perforated plate, in relation to the machine direction, can be controlled. The perforated plate is supported, at both opposite ends thereof, on vertical side walls of the head box, by fittings which permit thermal expansion and contraction of the perforated plate.

Abstract: A roller device attachable to the frame of a Fourdrinier paper-making machine near the lateral edges of the forming fabric in the sheet forming zone to press against each of the lateral edges of the forming fabric and cause them to curl upwardly so as to contain the fibrous slurry on the forming fabric.

Abstract: Apparatus for a paper making machine to form multi-ply web including a headbox having an upper and lower chamber for low consistency fibrous stock to form the outer surface plies of a finished web and an intermediate chamber for receiving a high consistency stock for an intermediate ply with the headbox chambers delivering to portions of a slice chamber, with the outer portions of the slice chamber discharging through a slice opening onto a travelling forming surface and such slice chamber portions having flexible fine scale turbulence trailing elements unsupported at their downstream ends, and the slice chamber having an intermediate passageway receiving stock from the intermediate chamber of the headbox and being defined between solid walls which have inwardly facing surfaces forming a high efficiency tortuous undulating path for the high consistency stock flowing therethrough.

Abstract: A paper machine screening apparatus generally includes a centrifugal pump member mounted for rotation about the axis of a tubular screen plate. A delivery passageway extends concentrically about the pump impeller for receiving pumped stock flow and includes an annular axially extending passage formed between a ribbed hub surface of the pump and the screen. Flow through the screen is passed from the screening apparatus to headboxes. Downstream of the annular passage is an end cavity for receiving particles unable to pass through the screen holes which are washed into the end cavity by the axial flow through the annular passage. The ribbings on the hub surface serve to agitate the stock flow to raise pressure forces tending to force flow out through the screen holes.

Abstract: Holders for floating slice chamber dividers are provided with flexible bodies whereby the dividers are relieved from bending strains in their upstream attached end portions. Advantageously these holder facilitate orientation of the slice chambers of headboxes in a manner to provide for unusual compactness in headbox construction and space requirements. Purging of air from the stock flow is facilitated.

Abstract: A microturbulence generator for a papermachine headbox flow channel complying with newly developed parametric criteria for optimizing its effectiveness and methods of adjusting the position of said microturbulence generator while said papermachine is in-use to accommodate changes in operating conditions and/or machine speed are disclosed. A microturbulence generator complying with the optimization criteria of the present invention serves to generate a sufficient degree of microturbulence near the headbox throat to effectively disperse pulp floc in a macroturbulent stream of papermaking fibers to improve formation characteristics, randomize fiber orientation and reduce tensile ratio in the resulting paper web. The disclosed criteria are generally applicable to headbox flow channels having an angle of convergence between about 4.degree. and about 20.degree. and are particularly effective at papermachine speeds in excess of about 800 feet per minute.

Abstract: Thin plastic flexible trailing element sheets which divide the slice chamber of a papermaking machine headbox into substantially uniform turbulence channels between the slice opening and the flow divider plate between the slice chamber and the preslice chamber of the headbox, are anchored to the plate by means of rods having greater coefficient of thermal expansion and maintain the sheets substantially free from wrinkling in the presence of heated paper stock.

Abstract: A method and mechanism for compensating for pressure fluctuations in a paper machine stock flow system for conducting stock from a supply pump to a slice opening including providing a flexible diaphragm as one wall of the stock conduit with the diaphragm dampening pressure variations and being supported on its opposite side by air in an air chamber divided into compartments with a support compartment immediately opposite the diaphragm and a supply compartment behind the support compartment and the compartments divided by an attenuator wall. Air is supplied continuously at a reference pressure to the supply compartment, and a relief valve is positioned in the support compartment with the port opened or closed by movement of the diaphragm so that air is bled from the support compartment as the diaphragm moves toward the stock conduit with a drop of pressure therein.

Abstract: A headbox construction for a papermaking machine which comprises a slice chamber connected to a preslice flow chamber by means of a perforate member. The slice chamber contains a plurality of plates and/or filaments attached to said perforate member and extend in the direction of stock flow through said slice chamber and define therein a multiplicity of relatively narrow channels of decreasing cross-sectional area in the direction of flow.