Abstract: A method and apparatus for temporarily separating a web from one of the two wire belts in a twin wire zone in a paper making machine. In the twin wire zone, the negative pressure from a suction box is applied to the first wire belt for temporarily deflecting and separating the first wire belt and the web from the second wire belt and the wire belts then returning to contact the web following the suction box. The wire belts are then successively separated from the web by an appropriate guide and take up device. The take up device may comprise a press which includes a press nip defined by one of a suction roll over which the second wire in the web is passing or another type of roll or a flexible support device like a rotating press jacket. A smooth surface, such as that of a roll, forms a press nip with the support device for the second wire belt and after that press nip, the web adheres to the smooth surface to be transported further through the machine.

Abstract: The axes of a first press roll (1) and of a second press roll (3) lie in a press plane (E). Each of the press rolls has a journal pin (2) and (4), respectively. The first press roll is supported in a first bearing pedestal (5). The second press roll rests in a second bearing pedestal (6) which is coupled to the first bearing pedestal (5) by utilizing flexurally soft tension bars (7, 8). In the unloaded condition of the roll press, the second bearing pedestal (6) rests on the first bearing pedestal (5). In the loaded condition, play (p) is established between the bearing pedestals (5 and 6) so that the bearing pedestals (5 and 6) are displaceable axially relative to each other.

Abstract: A cantileverable roll for use in a roll press, wherein the cantileverable roll cooperates with a backing roll. The cantileverable roll has a rotating surface and is either a solid rotatable roll body or a stationary roll body with a rotatable shell around it. A journal at each end of the cantileverable roll is supported in a respective bearing bracket. At one end of the roll, preferably the drive end, there is a non-rotating extension piece which extends out axially from the roll body and is fastened to the bearing bracket at that end. A tension bar or the like connects the extension piece to a stationary structural part and introduces force in the roll body which compensates for the weight of the roll when the other end of the roll is temporarily unsupported and the roll is cantilevered. The backing roll may also be cantilevered. The various techniques for supporting the one end of the roll by using the coupling element from the extension piece to the frame of the paper making machine are disclosed.

Abstract: A method and device for the continuous transport of a liquid-gas mixture from an inlet reservoir having a first liquid level to a discharge chamber having a second liquid level includes a suction tube connecting the inlet reservoir and the discharge chamber, a gas separator disposed in the suction tube, and a conduit through which a gas passes to the second liquid level.

Abstract: A wet-press arrangement. The flexible press jacket of a shoe press roll removes the web to be dewatered in a first press nip directly from the wire on which the web has been formed. The web then passes, together with the press jacket, through a second press nip which is developed as a felted, lengthened press nip. The web then passes through a third press nip where it is transferred from the smooth outer surface of the press jacket onto the smooth outer surface of a press roll. The web then travels, together with the latter roll, through a fourth press nip, which again is developed as a felted, lengthened press nip. Following that, the web still follows the press roll up to a place of web removal.

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

Abstract: A method of treating the edges of a fiber web is provided wherein a pressing device device conveys and presses a fiber web through a pressing gap of a pressing station of the device. The station includes a pressing roll and a counter roll. The pressing roll has a roll shell. A pressing shoe is disposed within the roll shell and pressing units are disposed substantially along a width of the pressing shoe transverse to the direction of movement of a fiber web through the pressing station. The pressing units press against the pressing shoe which in turn presses a pressing surface of the shoe against an inner surface of the roll shell in a series of zones. The pressing units including pressing/pressure relief elements. The pressing force of the pressing/pressure relief elements is reduced in a step-wise fashion, zone-by-zone, from a normal operating level to a lower level in a region that includes the fiber web edges and the pressing shoe ends.

Abstract: A wet press for a paper making machine presses out water from a moist paper web. The wet press has a plurality of press rolls, preferably five. The press rolls are paired so that each pair defines a respective press nip. There are preferably at least four press nips defined by the paired press rolls. The press rolls are so placed and the press nips are so defined and the web is so trained on the path through the wet press that the paper web is always supported by the outer surface of one of the press rolls on the web path from the first press nip to the last press nip. At the second press nip in the path of the web, each of the press rolls there forms a felt free second press nip and each of the press rolls at the second nip has a closed outer surface. The same may be true for the fourth press nip. Some of the press rolls may be shoe press rolls.

Abstract: The invention is directed to a press system of a paper machine for making tissue, including a crepe drying cylinder, a press roll with a smooth surface, an extended-shoe press unit, and a press roll fashioned as a suction roll or grooved roll. A first press gap is formed by the press roll with a smooth surface and the press roll designed as a suction roll or grooved roll. A water collection tub is coordinated with the suction roll or grooved roll. A second gap is formed between the press roll with the smooth surface and the extended-shoe press unit after which the felt leaves the periphery of the press roll with the smooth surface. Following thereafter, a third press gap is provided between the press roll with the smooth surface and the crepe drying cylinder. The felt does not pass through the third press gap.

Abstract: A roll for the preparation or treatment of fiber webs includes a fixed central axis, a roll shell adapted to rotate around the fixed axis and a first chamber disposed between the central axis and the rotatable roll shell. The first chamber is filled with liquid which can transfer a hydraulic supporting force from the central axis to the roll shell. The roll includes a second chamber that is partially filled with air and partially filled with a liquid. Several narrow capillary lines connect the first and second chambers. The capillary characteristic (K) of the capillary lines ranges between about 2.5.times.10.sup.7 m.sup.-2 and about 2.5.times.10.sup.8 m.sup.2.

Abstract: An angularly adjustable drainage foil for paper machines. A facultatively two-part support structure extends across the machine width, and comprises a first beam and a backing shape mounted on it. A facultatively two-part cover strip extends across the machine width, and consists of an upper, wear-resistant foil strip and a support shape supporting the foil strip. A moving device effects a relative longitudinal motion of the cover strip and support structure. As the cover strip and support structure are moved relative to each other, the angle of incidence .alpha. between drainage surface 12b and the wire surface running over it is influenced. Provided between the underside of the cover strip and the top side of the support structure are compression means which force the claws of the cover strip on the respective backing surfaces of the support structure.

Abstract: A press jacket is formed of an elastomeric jacket material having two layers of reinforcement threads, namely an inner layer and an outer layer, embedded in it. The inner layer is formed of longitudinal threads which upon operation of the press device extend parallel to the axis of rotation of the press jacket. The outer layer is formed by a fabric layer or by circumferential threads which are wound helically and which, upon operation of the press device, extend approximately in the direction of travel of the press jacket. The reinforcement threads are surrounded by the layer of elastomeric material, which is produced homogeneously. The inner surface of the press jacket has longitudinal grooves which extend parallel to the longitudinal threads and have a depth of 0.1 to 0.2 mm. Various techniques of forming those grooves are described, including enlarging the longitudinal threads, pressing on the jacket which thereby deforms around the threads, forming voids or channels (i.e.

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

Abstract: A wet portion of a paper machine, including a wire section and a pressing section has a plurality of roll presses. Each roll press includes two rolls defining a press nip. A water impervious belt having a smooth, non-porous surface is disposed in a continuous loop about at least two roll press rolls disposed consecutively with respect to a direction of conveyance of a paper web through the machine. Each press roll is associated with at least one counter roll or one shoe roll defining first and second press nips of the pressing section. The belt deflects about 180.degree. about each of the press rolls.

Abstract: A roll press with two press rolls which together form a press gap and whose axes are situated in a press plane. A journal is disposed on the ends of each roll, with pillow blocks for receiving the journals, with a rack for supporting the pillow blocks, and with tie rods which are arranged on both sides of the press plane and at least approximately parallel to it. Cradles are provided which support the pillow blocks. Between the cradles and the pillow blocks is an articulated joint which enables the pillow blocks to pivot about an axis which extends perpendicularly to the press plane and essentially in the axial plane of the respective roll.

Abstract: Two press units have axes which lie in a pressing plane which is inclined to the vertical direction and they form a press nip with each other. The two press units are supported by bearing brackets which are coupled in pairs to each other by detachable tension bars which transmit the pressing force. The bearing brackets of the one press unit are supported rigidly (i.e. directly on a machine frame, foundation, or the like) and bear at least a part of the weight of the other press unit. A support device on the machine frame, foundation, or the like at least temporarily takes up a component of the weight of the other press unit which is directed transverse to the pressing plane.

Abstract: A machine frame for supporting at least one dewatering element (a roll, suction box or the like) over which an endless belt (a wire or felt) may travel upon operation of a paper manufacturing machine, wherein:a) the dewatering element (10) has an operator-side end and a drive-side end;b) a beam (11) which extends substantially parallel to the dewatering element (10) is connected in torsionally rigid manner;b1) to a first frame part (12) for supporting the drive-side end of the dewatering element (10) and which rests in tilt-proof manner on a foundation (9);b2) and to a second frame part (13) for supporting the operator-side end of the dewatering element (10) and which rests on the foundation (9) via removable intermediate pieces (14); andc) an extension (15) of the beam (11) extends beyond the operator-side frame part (13), the outer end of the extension (16) being adapted to rest on the foundation (9),the improvement wherein:d) the beam (11) is a single beam arranged laterally alongside of the dewatering ele

Abstract: A calender for treating a material web, particularly a paper web, with at least two rolls forming with each other a roll gap for passage of the web, with a heating system and with a removable cover system. The cover system comprises a foil which is tightened at least around part of the circumference of at least one of the rolls while forming a machine-wide gap between itself and the shell surface of the respective roll, and extending in planes situated parallel to the roll axes.

Abstract: A multi-roll calender for treating a web material, of the type which develops a linear force, has at least two rolls stacked one above the other in a press plane. A lower roll is constituted as a sag-compensation roll. The other rolls in the calender stack are all equidistant relative to the sag-compensation roll, i.e., they are supported the same distance away from the two supports of the rolls. One of the outermost rolls (either the top or the bottom roll) is fixed in a stand while all the other rolls are movably mounted. The moveable rolls can be acted upon by support forces acting in the plane of the stack. The support forces and the internal pressure of the sag-compensation roll are adjustable via a control device, e.g., a computer, so that even when the rolls sag, the linear force distribution of the rolls is identical over their width.

Abstract: In a paper making machine a porous support belt travels together with the web over a drying cylinder and leaves the cylinder at a point of removal. A suction box provided in the region of the web removal has a suction zone which is defined by means of two yieldable sealing strips which extend transversely to the direction of travel of the web, and each is supported in a sealing strip holder. The distance between each sealing strip holder and the outer surface of the drying cylinder amounts to at least 30 mm, and each of the yieldable sealing strips has, in its normal condition of operation, such an inherent stiffness that the sealing strip remains substantially free of deformation in the event of a difference in pressure of 0.01 to 0.1 bar between the suction zone and its surroundings.