Abstract: An extended-nip press device comprises a press shoe extending in a cross-machine direction and a support for supporting the press shoe. Between the shoe and the support are arranged a plurality of loading cylinders for moving the shoe toward a backing member such as a counter roll to apply pressure to a fibrous web passing through the nip between the shoe and counter roll. Each loading cylinder comprises a first cylinder member fixed on the shoe and a second cylinder member fixed on the support, and a connecting member that slidably engages both cylinder members. The connecting member can slide relative to the first cylinder member with a first stroke length L1 that is smaller than the stroke length L2 between the connecting member and the second cylinder member. Accordingly, the connecting member can remain essentially aligned along the lengthening direction of the loading cylinder.
Abstract: A method to simultaneously de-water and form a sheet of pulp is disclosed. The method employs a pair of wire meshes, the meshes being adapted to move continuously under tension and to receive pulp continuously from a stock inflow tank. A layer of pulp is subjected simultaneously to progressive mechanical compression and to aspiration of the water at a constant value owing to a siphon effect. Also disclosed is an apparatus to carry out this method.
Abstract: The present invention is an air guide box. The box has a guide wall intended to lay adjacent to a running web. The guide wall has an air suction channel and a discharge opening. A drive jet blows air into the air suction channel to create suction, with the air being expelled through the discharge opening.
Abstract: A method of and arrangement for resisting formation of undulations in a fiber/water mixture supplied onto a forming wire at an open planar wire section of a paper-making machine include establishing over the wire an air curtain extending over the full breadth thereof, in the region of which the air mass upon the wire is set in motion. The direction of movement of the air mass is the same as the traveling direction of the wire, and the velocity of the air substantially equals the speed of the wire. The air curtain commences on the planar wire section, in the machine direction, only at a given distance from a lip slice of a headbox of the machine, and the air curtain extends along the traveling direction of the web over the planar wire section over a given distance.
August 20, 1987
Date of Patent:
January 9, 1990
Valmet Oy, Kymmene Oy
Raimo Malkki, Paavo Jaatinen, Timo Haverinen, Pekka Eskelinen, Juhani Jokinen, Vesa Vuorinen, Raimo Virta, Martti Salmivaara
Abstract: Method and device in a press section of a paper machine for detaching a web from a smooth face of a press roll. Momentary and local heating effect is directed at the web from outside the roll within the area or vicinity of a detaching point thereof. Material is used as the mantle or outer coating of the smooth-face roll which is at least somewhat magnetically conductive. An inductive heating effect is applied to the roll mantle free of contact therewith, and of such a high frequency, that depth of penetration of the heating effect remains sufficiently low in view of the local and momentary nature. Due to this heating effect, water present between the web and roll face is heated, even vaporized locally within the area of the detaching point, thereby detaching the web from the roll face. The electrical frequency of the induction heating is generally within the range of about 0.5 to 2 mHz, preferably within the range of about 0.8 to 1.5 mHz.
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.
June 13, 1988
Date of Patent:
December 19, 1989
Sulzer-Escher WYSS GmbH
Elmer Weisshuhn, Alfred Bubik, Hans Dahl, Herbert Holik, Rudiger Kurtz, Anton Zembrot, Wolf-Gunter Stotz, Werner Seider, Robert Trondle
Abstract: A paper machine includes a press section in which the paper web is carried along between a pair of paper machine felts. A dewatering apparatus is included in the press section which consists of a pair of opposed press rollers, one on either side of the felts, with the rollers forming a nip. The rolls are pressed toward each other to compress the felts and the paper web to the maximum mechanical compression. Compressed air is passed through one roller at the nip to the other roller which includes an exhaust device for draining the water blown through by the compressed air. The air is passed under pressure at the nip to evacuate water from the pores of the compressed felts and web. When the paper advances from the nip into an environment at atmospheric pressure, the paper web is substantially free of water.
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: The present invention concerns a device for generating negative pressure inside a cylindrical roll mantle of a revolving roll. The roll has a roll mantle provided with through-holes, grooves or equivalent apertures and confining a suction chamber in the interior thereof, in which a negative pressure can be generated by suctioning air out of the suction chamber. A suction flow directed towards the suction chamber thereby prevails in the holes, grooves or equivalent apertures of the roll mantle. At least one rotor blower or equivalent is attached to the roll to revolve along with the roll, with an intake side of the rotor being connected to the suction chamber of the roll. The movement of rotation of the roll thereby produces rotary movement of the rotor or equivalent, which in turn generates negative pressure in the suction chamber. Thus, in the arrangement in accordance with the present invention, external equipment of negative pressure or a separate piping system is not needed.
October 27, 1988
Date of Patent:
November 21, 1989
Valmet Paper Machinery Inc.
Pekka Eskelinen, Vesa Vuorinen, Seppo Rantanen
Abstract: A papermaking machine is modified by replacing a conventional rotatable couch roll by a stationary couch device that still serves the essential functions of the roll, namely dewatering of the furnish carried by the web and modification of the direction of travel of the web to turn it down towards the main drive roll. This stationary device is made of an abrasion resistant ceramic material and has a member with a convexly curved upper surface on which the web slides. Water is sucked from the furnish by a vacuum applied through perforations in the member. The majority of these perforations preferably take the form of slots that extend obliquely to both the transverse extent of the machine and the direction of web travel. The arrangement permits easier and more effective maintenance of the vacuum than with a couch roll and more efficient dewatering, with no rewetting of the web or furnish when leaving the couch device.
Abstract: An apparatus is disclosed for making a paper web from stock. The apparatus includes a first and a second forming wire which cooperate together to define therebetween a web-forming section having a first and a second end. A headbox is disposed adjacent to the first end of the forming section for ejecting the stock between the wires such that the web is formed from the stock during passage of the stock from the first towards the second end of the forming section. A first felt is disposed downstream relative to the forming section with the first felt running contiguously relative to the second wire such that the second wire is disposed between the first felt and the web. A second felt is disposed downstream relative to the forming section and on the opposite side of the web relative to the first felt.
Abstract: A paper machine headbox slice lip rotector system which permits limited incremental movement up or down by means of a pivoting lever arm 32 with lock bolt end portions 36 and 38 moving in adjacent protectors' adjustable keeper recesses 40. The recesses 40 are defined by stop nuts 42 on a threaded body fixed to the adjustable spindles 20. The lever arm 32 is pivotally mounted on the body for permitting up and down movement a distance which is the average of the distance defined by the keeper recesses 40 of the adjacent protectors. This prevents the prior art problem of a protector being "locked" between adjacent protectors.
Abstract: The frame construction in the press section of a paper machine in which the press section includes a combination of rolls which form at least one nip, members for guiding the paper web through the press section and members for guiding at least one felt into contact with the press section. The frame construction comprises a front frame, a rear frame and an intermediate frame connecting these two from above the press section. The connections of the intermediate frame both to the front frame and to the rear frame are releasable in order to remove the intermediate frame in a substantially horizontal and longitudinal direction from above the roll combination into a supporting member.
Abstract: A nozzle-like, machine-wide stock channel forms a stock discharge opening to which is allocated a device for adjusting the basis weight cross direction (CD) profile of the paper web produced in the paper machine. The device has a profile bar extending across the machine width. This is connected to an expanding member supported at the headbox in which are arranged pressure chambers disposed in succession across the machine width. By pressurization of the chambers of the expanding member consisting of an elastic material, this can be deformed. The deformation is transferred to the profile bar and in this way the effective width of the stock discharge opening changed.
Abstract: A belt on drum-type press which provides for utilization of a maximum amount of the drum circumference and provides a wide latitude of choice in the relationship between belt tension and press roll nip forces on the drum. In the preferred embodiments the press has a central drum free of axial bending moments and stresses.
Abstract: A device for drawing in an endless belt into a machine which manufactures paper, cardboard, or the like, includes a frame having a draw-in side over which the belt is drawn in and having an opposite side. An auxiliary support for the belt and off which the belt is transferred is moved up to the draw-in side of the frame. The frame has at least one cantilever piece extending beyond the draw-in side toward the auxiliary support. The auxiliary support has a corresponding cantilever arm. A lift device joins the cantilever arm with a respective cantilever piece to provide lift of the cantilever piece. The frame on the draw-in side has a removable intermediate piece, removable to permit the belt to be drawn in while the cantilever arm supports the cantilever piece and thereby supports the draw-in side of the frame. With the intermediate piece reinstalled in the draw-in side of the frame, the auxiliary support may be removed. In a one-belt height arrangement, the auxiliary support is generally C-shaped.
Abstract: A transfer apparatus is disclosed for transferring a web from a press section to a first dryer of a dryer section. The apparatus includes a lead-in roll which is disposed closely adjacent to the press section. A felt extends around the lead-in roll and from the lead-in roll to the first dryer such that the web extends in an "open draw" from the press section to the lead-in roll and is thereafter supported by and beneath the felt towards a dryer nip defined between the felt and the first dryer. A vacuum generating device is disposed adjacent to the dryer nip such that the web and the felt are disposed between the vacuum generating device and the first dryer. The web is disposed between the felt and the first dryer, and the vacuum generating device induces a partial vacuum in the vicinity of the nip so that wrinkling and breakage of the web as the web approaches the nip is inhibited.
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: An apparatus and method is disclosed for removing fluid from a fibrous web. The apparatus includes a press member and a blanket which cooperates with the press member for defining therebetween an elongate pressing section such that the web is pressed between the press member and the blanket during passage through the pressing section. An elongate shoe urges the blanket towards the press member such that when the web passes through the pressing section, fluid is removed from the web. A heater is disposed adjacent to the press member for transferring heat to the web such that when the web passes through the press section, the web is subjected for an extended period to increased pressure and temperature so that water vapor generated within the pressing section during passage through the pressing section forces the fluid in the liquid phase away from the web. The press member defines a pressing surface which is porous so that delamination of the web is inhibited.
August 27, 1987
Date of Patent:
October 17, 1989
Jeffrey H. Pulkowski, Elizabeth A. Macklem, L. H. Busker