Abstract: A doctor system (20) and an associated method for cleaning the moving surface (30) of a papermachine component (22) which is begrimed or wetted by a paper web (28) moved around the surface utilizes an air nozzle (54) supportable in a stationary condition adjacent the surface of the papermachine component for directing a stream of air in the form of a knife from a source generally toward the surface to dislodge grime and water from the surface. The system also includes a collection receptacle (68) positionable adjacent the nozzle for collecting grime and water which are dislodged from the surface by the air knife for disposal.

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: Procedure for the drainage of the wire and/or press section of a paper machine, in which procedure at least one suction pipe (1) is provided with at least one gap (2) and the suction pipe (1) is connected to a vacuum device (4) to develop a vacuum at least in this vacuum pipe, and in which procedure a felt, wire or equivalent (3) is moved over the gap of the suction pipe, water being thus drained from the felt, wire or equivalent. In the procedure, the vacuum capacity is adjusted by measuring and/or adjusting at least the amount of water drained from the suction pipe (1) and, on the basis of the measured data, adjusting the vacuum capacity by means of regulating devices (11, 12). The invention also relates to an apparatus for adjusting the vacuum capacity.

Abstract: The invention is directed to a paper making machine having a wet end associated with a wet fiber web. A forming fabric has a plurality of voids therein and carries liquid from the fiber web. A roll disposed at the wet end of the paper making machine carries the forming fabric. The roll and the forming fabric define a diverging area therebetween which causes liquid in the forming fabric to exit the voids. A doctor back includes a doctor element associated with the roll. A shower provides a liquid output which is directed relative to and lubricates the doctor element. A suction chamber has an at least partially open top and an outlet. The open top is positioned relative to each of the doctor blade and the diverging area to collect liquid from the shower and liquid exiting the voids in the forming fabric in the diverging area. A cyclone separator connected to the suction chamber receives liquid from the suction chamber outlet.

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: 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: A twin screen paper forming apparatus is provided having upper and lower screens moving in a first direction and wrapping around a portion of a leading forming roller positioned at the beginning of a forming zone where the upper and lower screens converge to form a twin screen. At least one stationary forming element is positioned downstream of the leading forming roller to contact with the lower screen. A water guide element is also located in the region of the forming zone approximately at the start of the forming zone. At least one forming rail contacts the upper screen and a pulp suspension discharge nozzle is positioned, to prevent preliminary draining, upstream of the location where the upper and lower screens converge.

Abstract: A saveall apparatus is disclosed for collecting water ejected from stock through a forming wire of a papermaking machine. The apparatus includes a box which is disposed closely adjacent to the forming wire. The box defines an enclosure which is connected to a source of partial vacuum so that water ejected from the stock is collected within the enclosure. A throat wall is rigidly secured to the box and has an upstream and a downstream end. The upstream end of the throat wall slidingly engages the forming wire. A moveable throat wall cooperates with the throat wall for defining therebetween a vacuum slot which is connected to the enclosure such that the water ejected from the stock is drawn by the partial vacuum through the vacuum slot into the enclosure. The throat wall is disposed in a first plane, and the moveable throat wall is disposed in a second plane such that when the moveable throat wall is moved relative to the throat wall, an angle defined between the planes remains constant.

Abstract: This device, preferably formed as a dual paper machine, has according to a preferred embodiment two endless screens, mainly a lower screen (21) and an upper screen (22). The lower screen (21), on which is formed a paper web, and the upper screen (22) are moved together in the lower part of a dehydration cylinder (25) arranged in the upper screen. Both screens (21,22) are unrolled from the rising lower quadrant of said cylinder (25) and are laid on the upper part of the support cylinder (26) arranged in the lower screen (21). The bandage of the dehydration cylinder (25) has hollows which absorb water from the screens along their arcs of contact with the cylinder and which project the water towards the inside of the loop formed by the screens of the cylinder. In the feed direction of the screens and downstream of the support cylinder (26), there is arranged a receiving container (36) for the projected water.

Abstract: All of the essential operating parts for adding a top former assembly to a new Fourdrinier paper machine or for converting an existing Fourdrinier paper machine into a top former are carried by a supplemental frame assembly which can be mounted on the main Fourdrinier frame with minimal modification of the latter except the addition of simple parts for securing the supplemental frame assembly on top of the main frame. The primary operating parts of the top wire assembly are a hollow foraminous roll and a top wire deflector which cooperate to collect and deliver liquid expressed through the top wire into a receptacle that is carried by the supplemental frame assembly, and special provision is made for utilizing the top wire deflector to correct for irregularities in the cross machine profile of the paper sheet as it is being formed. Provision is also made for operating the resulting top former in roll former mode, blade former mode, or a combination roll and blade former modes.

Abstract: All of the essential operating parts for converting an existing Fourdrinier paper machine into a top former are carried by a supplemental frame assembly which can be mounted on the main Fourdrinier frame with no modification of the latter except the addition of a pair of pivotal mountings and a pair of adjusting jacks for the supplemental frame assembly. The primary operating parts of the top wire assembly are a hollow foraminous roll and a top deflector which cooperate to collect and deliver liquid extruded through the top wire into a receptacle which is carried by the supplemental frame assembly. Provision is also made for operating the resulting top former in roll formation mode, blade formation mode, or a combination roll and blade formation mode.

Abstract: White water at a high speed of current occurs in the region of a forming roll in a paper machine running at a high speed. The white water is caught in a white water trough which is provided with deflection vanes and is carried substantially at the initial speed by means of a duct (1) out of the ground plan of the paper machine to a stilling tower (2) standing adjacent to the paper machine, to feed the inner wall of a screen wall (3) of a screen cage, which wall is arranged in the stilling tower. The wall (3) is curved and has openings (4) for the white water to pass through. They are designed to peel off in layers the film of white water which is sent along the wall (3) and to deflect the jets of white water passing through the openings (4) radially outwards to the wall (3) against an outer wall (5) of the stilling tower (2), where the actual deceleration of the current takes place in several individual jets.

Abstract: Apparatus for supplying deaerated stock to a processing machine incorporates an enclosed receiver and an open receiver open to the atmosphere. Stock deaerated by vacuum in the enclosed receiver flows to the processing machine, preferably via the open receiver. Some of such stock spills over a weir associated with the open receiver to maintain a constant-level pond in such receiver. Such constant-level pond minimizes stock pressure fluctuations at the machine. The apparatus may be provided with devices for controlling the level of stock in the conduit leading from the enclosed receiver and for passing stock from the enclosed receiver to the conduit in a predictable flow pattern to minimize generation of pulsations at the entry to the conduit. The stock spilling over the weir in the open receiver is recycled. During a temporary shutdown of the processing machine, the system may be maintained in operation with continuous recirculation of stock through the receivers to facilitate rapid restarting of the machine.

Abstract: Apparatus for supplying deaerated stock to a processing machine incorporates an enclosed first receiver and a second receiver open to the atmosphere. Stock deaerated by vacuum in the first receiver flows to the second receiver. Some of such stock spills over a weir associated with the second receiver to maintain a constant-level pond in such receiver. Stock is supplied to the machine from such constant-level pond, so that the pond minimizes stock pressure fluctuations at the machine. The stock spilling over the weir is recycled to the first receiver. During a temporary shutdown of the processing machine, the system may be maintained in operation with continuous recirculation of stock through the receivers to facilitate rapid restarting of the machine. Because there is no need for a pond of stock in the enclosed receiver, such receiver may be compact. The system may be installed in a preexisting mill and space within a preexisting vessel may be used for the second receiver.

Abstract: A method and apparatus for forming a fibrous web between a pair of forming wires. The apparatus includes an imperforate rotatable roll and a pair of liquid permeable forming wires which meet about a portion of the surface of the rotatable roll. Means are provided for delivering a liquid suspension of fibers between the forming wires as the wires are being received about a portion of the rotatable roll. The specific improvement of the present invention is centered around an arcuate imperforate roof conforming to the periphery of the rotatable roll along a limited part of the portion in which the twin wires are forming the sheet, with injection means for injecting pressurized air along the surface of the roof to form an air film therealong. Collector means are provided at the end of the forming portion for collecting liquid expelled from the forming wires during their travel along the portion of the roll.

Abstract: A twin-wire web forming section in a paper machine includes a lower endless carrying wire which laps a forming roll and an upper endless covering wire which laps at least a part of the portion of the lower carrying wire which laps the forming roll. First and second substantially straight runs of the carrying wire are defined prior and subsequent to the forming roll, respectively, in the direction of travel of the lower endless carrying wire, the first straight run comprising the initial single-wire portion of a web-forming zone. An open-surfaced forming board is operatively associated with the initial single-wire portion. A headbox is disposed at the forward end of the initial single-wire portion, the longitudinal axis of which is substantially aligned with the direction of movement of the initial single-wire portion.

Abstract: Methods and apparatus for producing a web by injecting a jet of stock between two tensioned wires and running the wires over a circumferentially grooved forming cylinder. The cylinder grooves and a zone immediately on the other side of the wires extending from the forming throat where the web is injected to the web run-off point are in direct, open communication with the ambient atmosphere so that water is drained inwardly and outwardly of the forming cylinder as the web is being formed. The jet stock size, wire speed and wire tension are adjusted in relation to the radius of the forming cylinder so that the inward and outward drainage of liquid from the web occurs in relative amounts sufficient to avoid substantial two-sidedness of the web thus produced.

Abstract: A fibrous web is continuously formed between inner and outer endless foraminous forming belts between which stock slurry is fed from a headbox, the belts being held in tension as they wrap a first convexly curved forming run surface from which the outer belt is separated immediately following the forming run, the inner belt carrying the wet web then running over a second convexly curved surface from the offrunning side of which the inner belt is then separated and a porous pickoff belt is pressed by a substantial convex area of an imperforate pickup roll against the wet web on the inner belt, the inner belt being guided to diverge from the pickoff belt commencing at the off-running end of the convex area of contact of the pickup roll and the wet web being forced to adhere to the pickoff belt by the vacuum action of the imperforate surface of the pickup roll. By multiplication of the apparatus a multiply web can be formed.

Abstract: A shear roll is situated above an upper surface of a top run of a Fourdrinier fabric such that a lower portion of the shear roll is adapted to penetrate a pulp stock web situated on the Fourdrinier fabric. The shear roll is operated by an external source of power, the source of power adapted to drive the shear roll at a surface speed exceeding a linear speed of the fabric by greater than 3% and less than 8% of the speed of the fabric. The shear roll is situated at a location where a consistency of the pulp stock web considered on a fibre basis situated on the fabric is between 2% and 5 1/2%; and the shear roll adapted to provide a shearing action to fibre bundles and flocs situated in the pulp stock web as the pulp stock web passes between the shear roll and the fabric, there re-working the pulp stock web and re-forming the fibre network and smearing the flocs thereof.

Abstract: The web forming, guiding and/or transferring cylinder in the wire section of a papermaking machine has a deformable foraminous shell which is made of filamentary material and the end portions of which are clamped to rigid rotary ring-shaped end walls. The cylinder surrounds a rigid stationary back support which engages the internal surface of the shell opposite that portion of the external surface of the shell which contacts the web. The back support has grooves and/or ports which convey expelled liquid from the web into a suction chamber for admission into the saveall of the papermaking machine. One of the end walls is movable axially to change the axial tensional stress upon the shell. The back support has a convex external surface whose center of curvature may but need not be located on the axis of the cylinder.

Abstract: A curved deflector for intercepting high velocity sprays of liquids thrown from a moving member has holes formed in the portion of the deflector remote from the member for permitting substantially all liquid collected by the deflector to pass through the holes and in so doing be substantially slowed in velocity, thereby substantially eliminating aeration from splashing and considerably reducing noise.

Abstract: A wire is passed over the suction breast roll between the formed paper web and the doffer belt or the previously formed paper webs and doffer belt. The doffer felt is disposed in an unencumbered fashion over each of a plurality of consecutive suction breast rolls. The wire is removed from the web at a downstream point outside the dewatering influence of each breast roll. Stripping of the wire from the paper web is aided by various suction devices or couch rolls at this latter point.

Abstract: A whitewater system is provided for handling at high velocity the large quantities of water that are circulated in the high speed forming of pulp using a wire and forming wheel. Use of a centrifugal collector to transfer water from within a forming loop at velocities approaching that of wire speed permits the water to be partially deaerated automatically, so that return as white water to the pulping system is facilitated.

Abstract: A paper making apparatus for producing sheets of paper at speeds in excess of 200 m/minute. A breast roll and a wire cage turning cylinder are disposed above and below a forming roll. The forming roll is a hollow roll having a smooth surface. A belt passes in an S-shape over the forming roll and turning cylinder and a wire belt passes over the breast roll, forming roll and turning cylinder. The head box discharges raw material between the wire belt and the S-shaped belt, and a web is formed along the circumference of the forming roll over an angle of about 100.degree.. A web pick-up device is provided under the turning cylinder to separate the formed web from the wire belt.