Abstract: A method and device for the regulation of a pulp suspension flow in a multi-layer headbox and a multi-layer headbox for a paper machine/board machine. For the formation of different layers in the web, at least two pulp suspensions having different pulp concepts flow through the multi-layer headbox. The flow of a pulp suspension that forms one of the layers in the web is regulated by regulating the component flows that constitute this flow and regulating the concentration of the component flows independently from one another. In this manner, i.e., by regulating only this the particular layer, the total flow of the pulp suspension leaving the headbox is regulated.

Abstract: A paper machine headbox having divided sections for feeding pulp suspensions with different properties therethrough includes a single inlet line and a plurality of feed lines connected thereto. In at least one of the feed lines, there is a separation device which separates certain pulp suspension components from the pulp suspension flowing therethrough. A discharge line connected to the separation device conveys separated pulp suspension components therefrom. A continuing feed line connected to the separation device conveys the remaining pulp suspension to the headbox.

Abstract: The proposed multilayer head box for a paper machine or similar is constructed so that it can produce a wide jet consisting of at least three individual jets (5, 5', 5") The individual jets are fed through separate channels (3, 3", 3") and emitted out of the head box and subsequently combine to form a single wide jet. The individual channels are so constructed that further outer lying jets can be diverted sufficiently after having been emitted out of their respective channel, so that they meet the respective further inner lying partial stream at a very slight angle. The problem of separation when the partial streams are diverted as well as that of undesired lateral mixing when the partial streams are combined are thereby prevented.

Abstract: A method of manufacturing a web of fibers, especially a web of paper. The pulp is uniformly distributed through an outlet over the width of the machine and along a wire or between two wires. Most of the moisture is subsequently extracted from the pulp accommodated on or between the wires at a draining point. Various amounts of retaining agents are added to the pulp at sections across the headbox and the web in order to control the level of retention sectionally.

Abstract: Headbox for paper machines, provided with an output channel in the form of a nozzle, with an output slot for producing a strip of pulp having the width of the machine. The output channel is delimited by two flow guide walls converging toward one another and as a rule by a rear wall. It is divided up into a number of channel sections (32), preferably autonomous, by subdivision of the flow guide walls into wall sections (30, 31) and preferably by subdivision of the rear wall into rear wall sections (37). Each channel section may have at least one input line (40) of its own, as well as (for adjusting the opening of the output slot) a section of part of the mobile wall (35) and an associated regulating system (38, 39).

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: Sieve bend for separating particles of differing size in a liquid slurry. The bend structure defines a passage having an inlet end and a discharge end, with a throat of decreasing cross sectional area at the discharge end of the passage, and a sieve screen for receiving slurry flowing from the discharge end of the passage. The throat is formed in part by a movable member, with means for adjusting the position of the movable member to vary the cross sectional area of the throat and means for temporarily moving the movable member to an open position to clear debris from the throat. The sieve screen is mounted in a housing associated with the bend structure, and the housing is vibrated in a resonant manner to dislodge material from the screen. A repulping box is positioned midway along the screen for supplying additional liquid to the slurry as it passes over the screen.

Abstract: A headbox apparatus is disclosed for ejecting stock onto a forming wire for forming a web. The apparatus includes a housing which is connected to a pressurized source of the stock. The housing defines a tapered inlet for the flow therethrough of the stock. The tube bank has an upstream and a downstream end with the upstream end being connected to the tapered inlet such that the stock flows at a substantially constant flow rate through the inlet and through the upstream end of the tube bank to the downstream end of the tube bank. The tube bank includes a plurality of tubes for the flow therethrough of the stock. A member defines a slice chamber which has an upstream and a downstream extremity. The upstream extremity is connected to the downstream end of the tube bank, and the downstream extremity is disposed adjacent to the forming wire.

Abstract: A headbox tube bank apparatus and method of directing flow through same is disclosed for permitting the flow therethrough of stock in a papermaking machine. The apparatus includes a tube bank frame for rigidly supporting the tube bank, the frame defining a plurality of openings. A plurality of tubes cooperate with the frame such that each tube extends through and is supported by an opening. Each tube has an upstream and a downstream portion, the upstream portion defining an internal cross-machine direction section of substantially circular configuration for maximizing the velocity of the stock through the tube.

Abstract: A headbox is disclosed for ejecting stock onto a forming wire of a papermaking machine. The headbox includes an upper, lower, first and second side wall, with each of the side walls extending between the upper and the lower walls such that the upper, lower and side walls define therebetween a slice chamber for the passage therethrough of a primary flow of the stock. A secondary flow of stock is injected laterally relative to the primary flow such that the secondary flow extends through the side walls for controlling fiber orientation along the lateral side edges of the stock ejected from the headbox onto the forming wire.

Abstract: A headbox apparatus is disclosed for ejecting stock onto a forming wire of a papermaking machine. The apparatus includes a header for the flow therethrough of the stock. The header finds an inlet and an outlet, the outlet having an upstream and a downstream end. The header is tapered in a cross-machine direction from the upstream end towards the downstream end such that the flow of stock through the outlet remains substantially constant from the upstream to the downstream end. A distributor is disposed immediately downstream relative to the outlet and in fluid communication therewith. The distributor includes a plurality of distributor tubes which are disposed parallel relative to each other. Each of the tubes has an upstream extremity such that the stock flows from the outlet through each of the upstream extremities. Each of the extremities defines an upstream edge and a downstream edge such that for each tube, the upstream edge is nearer than the downstream edge to the upstream end of the outlet.

Abstract: The formation of paper webs produced by papermaking headboxes having damaged or imperfectly-formed headbox lips can be improved by providing the headbox with an extended flexible divider sheet which extends beyond the slice opening and is positioned adjacent the defective headbox lip. The extended divider sheet so positioned substantially eliminates the adverse effects of the defective lip on the stock jet characteristics.

Abstract: The uniformity of layered paper sheets produced using a layered headbox can be improved by confining the outer layers between parallel surfaces within the headbox immediately prior to leaving the headbox.

Abstract: A headbox for a paper machine with a stock channel featuring an outlet gap. The stock channel is preceded by a turbulence generator in the form of a machinewide bundle of many turbulence pipes. The turbulence generator is composed of two or three machinewide layers of turbulence pipes. The turbulence pipes of adjacent layers differ primarily by different flow cross sections, preferably also by different axial spacings a, A.

Abstract: A turbulence generator (20) in the headbox of a paper making machine which produces internal microturbulence in the pulp suspension flow (F), whereby the homogeneity of the flow is improved. The turbulence generator (20) comprises a system of turbulence tubes, which consists of a number of turbulence tubes (22) placed one above the other and side by side. These tubes start at the inlet side of the turbulence generator (20) having thereat a substantially circular cross-section, being gradually and smoothly, in the flow direction, converted to a rectangular cell structure with planar sides. The cell structure (30) at the outlet side (23) of the turbulence generator (20) consists of an overlapping cell system, wherein there are at least two inclined middle cell rows (31, 32; 31a, 31b, 32a, 32b) placed one above the other, in which cell rows the cells have rectangular cross-sections. The cells have a shorter planar side (X) and a longer planar side (Y).

Abstract: A head box in a paper machine, has a group of conduction pipes for guiding paper material from a mixing chamber into a slice. The pipes are fixed to a frame at one end of the head box on the side of the slice lip. Long portions of the group of conduction pipes, ending at end portions on the side of the mixing chamber, are not fixed to the frame. A perforated plate disposed at an outlet port side of the mixing chamber is also not fixed to the frame, and is connected to the group of conduction pipes. The group of conduction pipes thus freely expand and contract at their non-fixed ends on the side of the perforated plate. The perforated plate is integrally moved following thermal expansion and contraction of the group of conduction pipes, thereby absorbing the thermal expansion and contraction.

Abstract: The flow ratio of a paper machine headbox is adjusted by arranging such a by-pass out from the slice chamber that the flow conditions, such as the speeds and turbulences in all parts of the headbox remain unchanged regardless of the adjustment. The adjustment is carried out by opening the slice chamber wall or by using a separate discharging device positioned inside the slice chamber.

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: A feed device for paste-like mixtures such as paper pulp is designed to form a flat film of paste through at least one nozzle at the outlet from a distribution chamber. Paste-like mixture feed circuits discharge into the distribution chamber and each circuit comprises a liquid feed channel and a concentrated paste feed channel each incorporating a flowrate adjuster valve and connected downstream of the valves by a mixer. The mixer comprises an outlet connected to an inlet of the distribution chamber. The distribution chamber comprises ejection channels delimited by longitudinal partitions. Each circuit is in corresponding relationship with one ejection channel.

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 headbox comprising an inlet chamber communicating with a source of fiber suspension, an outlet chamber with a discharge opening for the fiber suspension and a diffuser to establish a fluid path between the inlet and the outlet chambers. The diffuser includes a cluster of tubes, each being divided in two successive portions of larger cross-sectional area separated by a step-like transition. Each tube comprises a stem mounted in the initial portion thereof to define a ring shaped fiber suspension passage.

Abstract: A trailing element device is disclosed for use in a headbox of a papermaking machine. The device includes a plurality of laminated sheets, the sheets being disposed within the headbox for dampening turbulence within the headbox. A binder cooperates with the plurality of sheets for binding the sheets together such that the trailing element device defines an upstream bead which extends in a cross-machine direction within the headbox. The bead is anchored within a slot defined by the headbox such that the bead is permitted to pivot within the slot so that a downstream end of the trailing element device is permitted to freely float within the headbox for attenuating the turbulence within the headbox. A wear resistant cladding is applied to the upstream bead for inhibiting wear and fracturing of the sheets caused by frictional engagement between the trailing element device and the slot.

Abstract: A papermaking machine including the combination of an endless moving screen having an upwardly-inclined run, a primary open headbox for supplying a moving stream of a primary liquid slurry into contact with the screen for forming a first sheet-like structure on the screen, the primary headbox including a pond regulator for cooperantly defining a discharge end for enhancing the discharge of the stream of liquid slurry into the upwardly-inclined run of the screen, a secondary closed headbox in a piggyback relation to and integrated with the pond regulator for supplying a moving stream of a secondary liquid slurry into contact with the screen and the advancing first sheet-like structure.

Abstract: A sieve bend has been described incorporating a headbox 40, throat mechanism 46, nip flap 90 and sieve surface area 52 supported by frame 96 which may have portions thereof rotated or positioned behind headbox 40 temporarily until its use is desired. The invention overcomes the problem of requiring frequent end for end reversal of the sieve surface area and of debris jamming the throat mechanism. Further, the invention permits in process variation of the sieve surface area 52 in response to downstream conditions.

Abstract: A stock delivery system is provided having a pair of inlet systems (one for large flow and one for small flow) selectively pivotally swung into operating position for charging a slurry through a perforated plate and into the following flow passage and slice which includes adjustments for optimum flow velocity by strategically-placed pivot points and adjusting mechanisms for controlling the heel and throat areas and the lip defining the slice.

Abstract: A head box has a dispersing section provided with a numerous paper material slurry flowing pores at an inlet side of a paper material slurry passage leading to a slurry slip. A reduced stream section is disposed at an outlet side of the dispersing section. The reduced stream section is adapted to reduce the distance of the paper material slurry passage. An evener chamber is formed between an inlet side of the reduced stream section and an outlet side of the dispersing section. A reduced stream gate is disposed at the reduced stream section. The reduced stream gate is adapted to regulate the distance of the reduced stream section. The reduced stream gate is disposed on a bottom surface of the reduced stream section. The reduced stream gate is provided with a shaft portion pivotable about a fixed supporting point and a circular arcuate gate portion formed in concentric with and projected from the shaft portion along a circular arcuate surface of the shaft portion.

Abstract: In a headbox of a web forming apparatus, a trailing elemnet device is disclosed for dividing a flow of stock flowing through a slice chamber of the headbox towards a slice lip of the headbox. The trailing element device includes a rectangular sheet having an upstream and a downstream end and a first and a second surface. The upstream end of the sheet is pivotally secured within the slice chamber for dividing the flow of stock into a first and a second current. The downstream end of the sheet freely floats adjacent to the slice lip such that the first current of stock flows past the first surface and the second current of stock flows past the second surface so that turbulence within the slice chamber is reduced.

Abstract: The invention relates to a headbox of a paper or board making machine, particularly a hydraulic headbox, which has an inlet header section (1) with a manifold tube section (2) and an equalizing chamber (3) in the stock suspension flow route, a turbulence generator section (4) following the equalizing chamber (3), after which a tapered slice section (8) is located, through which the stock suspension is discharged onto the wire. The headbox also has an attenuation chamber (6) for pressure variations, which defines one or several air spaces (7) under the flow channel of the stock suspension, the spaces being connected with the flow channel by way of a connecting channel (5). The air space or spaces (7) are preferably confined by subjacent frame structures including a bottom wall (16) and vertical walls (18) and walls (19) defining the flow channel from below.

Abstract: A headbox features in the machine-wide suspension channel, following in the flow direction of the suspension, a tubular distributing grid, an equalization channel, a turbulence generator, and a nozzle. Connected to the suspension channel is a device for dispensation of diluting liquid into the suspension. The amount of diluting liquid is adjustable across the machine width in contingence on the position of the basis weight cross profile variation in the produced paper web. The diluting liquid is dispensed directly before a choking point of the turbulence generator, into the suspension channel, in order to thereby prevent hydraulic disturbances, specifically cross flows in the suspension flow in the nozzle.

Abstract: A fiber stock suspension is directed from a guide device through the nozzle chamber of the headbox device and out of the slice opening thereof onto a papermaking machine. This nozzle chamber comprises at least two zones or sections. The first zone subsequent to the guide device possesses a relatively low convergence angle or low angle of wall inclination of the headbox device relative to the direction of flow of the fiber stock suspension. The other or second zone is positioned prior to or immediately upstream of the slice opening and possesses a substantially greater convergence angle or angle of wall inclination. In the first zone subsequent to the guide device, an improved flow stabilization or quieting of the flow of the fiber stock suspension occurs after the deflection of the fiber stock suspension and the creation of turbulence by the guide device. In the second zone prior to the slice opening the fiber stock suspension is strongly accelerated.

Abstract: In a headbox system for a papermaking machine with an adjustable distribution of the fiber stock suspension or pulp over the web width, the flow in the delivery slice is controlled in such a way that, across the web width, also the distribution of the fibers in respect of fiber orientation and quantity has a desired profile. For this purpose, the flow of the fiber stock suspension is controlled such that in the event of a change in the distribution of the fiber stock suspension across the web width, the horizontal component of the flow direction in the delivery slice remains, at all locations, always in the predetermined machine direction and thus transverse flows are avoided and the flow rate in the delivery slice has a predeterminate profile.

Abstract: In a headbox system for a papermaking machine with an adjustable distribution of the fiber stock suspension or pulp over the web width, the flow in the delivery slice is controlled in such a way that, across the web width, also the distribution of the fibers in respect of fiber orientation and quantity has a desired profile. For this purpose, the flow of the fiber stock suspension is controlled such that in the event of a change in the distribution of the fiber stock suspension across the web width, the horizontal component of the flow direction in the delivery slice remains, at all locations, always in the predetermined machine direction and thus transverse flows are avoided and the flow rate in the delivery slice has a predeterminate profile.

Abstract: The head box for a paper making machine joins the main distribution channel with an outlet nozzle that extends over the width of the machine. The head box has a plurality of linear, tubular flow channels extending from the distribution channel to the outlet nozzle. Just before entry into the outlet nozzle, each channel widens continuously, forming a continuous diffuser communicating into the outlet nozzle. In each tubular flow channel, a respective channel piece of reduced inside diameter is provided at or just upstream of the continuous diffuser. The entrance into the channel piece is developed as a step-like reduction in cross-section of the tubular channel, as compared with the cross-section of the tubular channel just upstream.

Abstract: Turbulence generator for the head box of a paper machine, the quality of the surface of the flow ducts of which has been improved and the manufacturing technique of which is simple. The turbulence generator according to the invention is characterized by the feature that the body of the perforated beams (6a, 6b) and the coating material of the face surfaces and the flow ducts are densely and tightly bonded to each other and that the coating materials of the flow ducts (7) is both physically and chemically wear resistant. The body of the beam is plastic, and the surfaces of the flow ducts have a ceramic coating on them.

Abstract: In a multi-ply headbox of a papermaking machine, a flexible partition foil or sheet is connected by an apparatus to a rigid partition element dividing the nozzle chamber. For rapid replacement of the flexible partition foil or sheet, the apparatus comprises an upper retaining strip and a lower retaining strip which are structured for force-locking or form-closed or form-locking clamping of the flexible partition foil or sheet therebetween and secured at the rigid partition element. Between the upper and lower retaining strips there is provided a pressure chamber of a pressure device, which pressure chamber can be impinged by a pressurized fluid medium for spreading or expanding, if necessary, the upper and the lower retaining strips. The pressure chamber possesses the shape of a continuous groove extending across the entire outlet width of the headbox.

Abstract: In a headbox system for a papermaking machine with an adjustable distribution of the fiber stock suspension or pulp over the web width, the flow in the delivery slice is controlled in such a way that, across the web width, also the distribution of the fibers in respect of fiber orientation and quantity has a desired profile. For this purpose, the flow of the fiber stock suspension is controlled such that in the event of a change in the distribution of the fiber stock suspension across the web width, the horizontal component of the flow direction in the delivery slice remains, at all locations, always in the predetermined machine direction and thus transverse flows are avoided and the flow rate in the delivery slice has a predetermined profile.

Abstract: In a multi-ply headbox, the nozzle chamber is subdivided by rigid partition walls into a number of nozzle chambers, and the slice openings or outlet slices are adjustable independently of one another. This is accomplished by providing a pivotable mounting of the partition wall or walls in a guide block, for instance, such pivotable mounting being accomplished by a substantially cylindrical shell or cup bearing structure. The desired pivotable movement or adjustment of the rigid partition wall can be undertaken by an inclined groove-cam guide arrangement effective at a projection of the partition wall or by pressure cushions, such as pressure hoses effective at both sides of the projection.

Abstract: A plurality of stages of parallel twisted plates extend in a slurry passage adjacent to a slice outlet of a head box in the direction of papermaking slurry flow therethrough and are spaced apart from each other by a predetermined distance. The twisted plates directly cause the slurry flowing through the head box to swirl. Adjacent vortex flows of the slurry interfere with each other, resulting in the violent agitation of the slurry.

Abstract: A headbox, preferably for a paper machine, has a nozzle chamber with a slice gap, which is confined by a top and a bottom lip wall and by two side walls. The nozzle chamber is divided for the production of multi-layer fibrous stock webs into two or more machine-wide flow channels. For this purpose at least one wedge-shaped partition wall extends through the nozzle chamber from one side wall to the other, with this partition wall projecting through the slice gap in the direction of flow. Each of the two side walls is subdivided along the partition wall into two side wall sections. The partition wall is clamped between the side wall sections in the area of each side wall.

Abstract: Method and apparatus in the headbox of a paper machine and in its approach pipe system. In the headbox, pulp suspension is fed through the approach pipe system and a pressure screen arrangement, if any, to a distributing header part, from which the pulp suspension flow is conducted through a turbulence generator section and further to a lip section. A pulp suspension jet is discharged from a lip aperture of the lip section onto a forming wire or into a throat defined by a pair of forming wires. At least part of the approach pipe system, the distribution header part, and the turbulence generator section are arranged to have two or several substantially parallel pulp suspension flow passages. The different passages operate substantially simultaneously in parallel, when the headbox has been set to operate in a higher flow rate range.

Abstract: A paper machine head box includes perforated plates being used as a distributor and a turbulence generator and having flow ducts, of which the ones at the edges are of different size than the remaining flow ducts. According to a preferred embodiment, slides, which are movable sideways, are provided at the ends of slice ducts at both edges of the perforated plates in order to regulate the flow. The slides and the perforated plates define the outermost flow ducts of the turbulence generator and the distributor.

Abstract: A head box in a paper machine, characterized in that a flow path having a repeatedly and alternately narrowing and broadening cross-section configuration is formed within a slice chamber delimited by a top plate and a bottom plate converging towards a slip lip.

Abstract: A method and apparatus for thickening a pulp, in particular a pulp containing fibres. The pulp is thickened hydraulically while it flows through a space between two screen surfaces. Thickening on alternate screen surfaces is prevented for cleaning by closing the valves in the outlets. Pulp is removed from the screen surfaces by vanes.

Abstract: Apparatus and method for laying down a fibrous web from a foam-fiber furnish. A headbox includes walls defining an elongate channel extending transversely of the direction of movement of the forming wire. Foam-forming nozzles are positioned to introduce foam-fiber furnish into the channel for turbulence - inducing impact on an oppositely disposed wall defining the channel. The turbulently flowing foam-fiber furnish is then introduced to the headbox slice for discharge onto the forming wire with minimized MD orientation of the fibers.

Abstract: A headbox for delivering stock to a forming surface in a papermaking machine with the headbox having a slice chamber and a slice opening and having trailing elements positioned in the slice chamber extending transversely of the headbox with means anchoring the elements only at their upstream ends with the downstream portion unattached and constructed to be self-positionable so as to be solely responsive to forces exerted thereon by the stock flowing toward the slice with the elements having greater structural stiffness in the cross-machine direction so that the elements offer resistance to deflection in a cross-machine direction by transient pressure variations and offer minimal resistance to deformation of the fluid flow stream for balancing forces on opposite sides of the elements with the elements in one form being laminated with a plurality of anisotropic layers.

Abstract: A headbox for a paper machine comprising a top plate and a bottom plate defining a chamber therebetween and a plurality of flow restraining elements disposed one above another in the chamber to define a plurality of paths spaced one above another therein. The top and bottom plates are connected to one end to a perforated plate defining an inlet for the chamber and approach each other as they approach an outlet for the chamber. Each element is removably connected at one end to the perforated plate, and the paths extend from the inlet to the outlet. Each element has a mildly corrugated upper surface and a mildly corrugated lower surface which approach each other until they terminate in a free end remote from the perforated plate. Those surfaces are substantially symmetrical to each other with respect to a center line of said element. Each element has a free end portion formed from an easily deformable material, such as rubber or plastics. The surfaces of each element define an angle of 1.degree. to 15.degree.

Abstract: A paper machine trailing element for use in a slice in a headbox wherein the trailing element is formed of laminations with a bead at the upper end for anchoring the element in a slice chamber with the bead formed of laminations with fibers on the outer surface in the machine direction and in the cross-machine direction within the bead so that the element has a greater stiffness in the machine direction at the upstream end with the element tapering to a thin tip at the downstream end and the downstream end formed of laminations with fibers extending in the cross-machine direction for a greater stiffness to minimize instability.

Abstract: A method and apparatus for forming a paper web from a fiber suspension are disclosed. These include injecting a fiber suspension stream through a slice opening onto the upper surface of a travelling paper web-forming surface, maintaining that surface free of support for a predetermined distance downstream of the slice opening, maintaining a flexible lip near the upper surface of the web-forming surface for a portion of that predetermined distance, and applying a vacuum to the lower surface of the web-forming surface throughout the predetermined distance. In this manner, both the method and apparatus can produce a paper web and substantially dewater the fiber suspension within the space between the flexible lip and the web-forming suspension and substantially reduce disturbances during formation of the web and throughout the predetermined distance.

Abstract: Apparatus is known for controlling the deposition of a liquid onto a moving surface comprising a reservoir having an outlet, and a curved guide member downwardly extending from above and adjacent to the outlet and having an underside onto which a jet of liquid can be discharged from the outlet, the guide member being oriented so as to be capable of causing liquid to flow down the member on its underside so that its direction of flow approaches the direction of travel of a moving surface.

Abstract: The multi-ply headbox has a number of, for example, three headbox elements comprising block-like infeed members containing mutually parallel distributor passages for the fiber stock suspension which open each into a nozzle chamber. Plate-like intermediate lip members or lips bound the nozzle chambers and are provided between the headbox elements. The plate-like intermediate lips are displaceably arranged between the infeed members. There are also provided outer lips or lip members which either can be structured as displaceable plates or may be constructed to be pivotable. One of the outlet slices can be altered without affecting the size of the other slices.