Abstract: The invention relates to a sag-compensation roll having a roll shell (1), a stationary yoke (2), and an oblong hydrostatic pressure shoe (8) which can be tilted about a longitudinal axis and contains hydrostatic pressure pockets (11, 12). The pressure shoe is fitted to the inside diameter of the roll shell (1) and is attached to a radially movable oblong piston (4) which is sealed off from the yoke (2). The longitudinal ridges (9, 10) which define the individual hydrostatic pockets (11, 12) have a width (a, b) equal to at most 1/20 of the width (K) of the piston. The pressure shoe (8) is hydraulically supported over the main part of its width on its lower side, i.e. the side which faces the yoke (2).

Abstract: A press roll in cooperation with a mating roll defines a roll nip for the treatment of a moving web of material with the press roll and mating roll being oriented to provide a non-vertical pressing plane. The press roll includes a rotatable roll casing and a yoke located within the roll casing. The roll casing and the yoke defining an intermediate space therebetween. Certain press roll parameters such as the dimensions and material of the roll casing and the yoke and/or the degree of filling of the intermediate space with a liquid are selected such that gravity induced flexures of the roll casing and the yoke occurring in a median plane perpendicular to the pressing plane are approximately equal.

Abstract: A hydraulic support device in a paper making machine for supporting a first beam (52) on a second beam (53), having a pressure cushion (54) between the two beams. The pressure prevailing in the pressure cushion is variable but it is uniform over the entire length of the pressure cushion. The pressure cushion (54) rests on a contact surface of the first beam (52). The width (b) of the contact surface as seen in cross section is less than the total width (B) of the pressure cushion (54). A free space (55) into which a loop of the pressure cushion (54) can penetrate is provided on each side of the contact surface.

Abstract: A press blanket for a press device in a paper making machine, or the like, is formed of an elastomeric blanket material and fully embedded layers of reinforcement threads. The radially inner layer is formed of longitudinal threads which extend parallel to the axis of the press blanket. The radially outer layer is formed of circumferential threads which are wound in the direction of blanket motion and are wound generally helically. The threads are fully surrounded by the layer of homogeneous elastomeric material, that is formed from a single pouring. The circumferential threads have a diameter of at most 1/500 of the outside diameter of the fully rounded press blanket. In a unit area of the press blanket, the tensile strength of the circumferential threads is at least 40% greater than the tensile strength of the longitudinal threads.

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 respective journal (2, 4). The first press roll is supported in a first bearing bracket (5). The second press roll rests in a second bearing bracket (6) which is coupled, by means of flexurally soft tie-bar groups (7a, 7b . . . , 8a, 8b . . . ), to the first bearing bracket (5). In the unloaded condition of the roll press, the second bearing bracket (6) rests on the first bearing bracket (5). In the loaded condition, however, a clearance (p) is established between the bearing brackets (5, 6), which permits the bearing brackets (5, 6) to be displaceable relative to each other in the axial direction of the press rolls.

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.

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: Apparatus for manufacturing a press jacket from pourable elastomeric material with reinforcement threads. A cylindrical pouring body. A longitudinal thread tensioning device at the pouring body. A feed device for feeding circumferential threads to the pouring body. A pouring nozzle for pouring the elastomeric material to the pouring body. A spacing device maintains a constant distance between the longitudinal threads and the jacket surface of the pouring body as well as a constant circumferential distance between adjacent longitudinal threads. The spacing device includes a plurality of segments. Each segment has an L-shaped cross section. The radial arm has slots for the passage of longitudinal threads and furthermore teeth present between the slots. A slide is rigidly fastened to the support and includes rollers which engage the segments and move the spacing device along the pouring body.

Abstract: A flexure compensated roll comprising a rotatable roll shell around a longitudinally extending support therethrough. A longitudinally extending press shoe supported on the support. A piston movably supported on the support above a sealed pressure space. The piston has a saddle toward the interior of the roll casing. The shoe has a middle pressure chamber fluid connected with the pressure space of the piston. The shoe also has rows of hydrostatic pockets on both circumferential sides of the middle chamber. These are supplied by narrowed choke passages with hydraulic fluid. The supply of hydraulic fluid to the hydrostatic pockets bypasses the piston pressure space and/or the middle chamber and is from a pressure source to the hydrostatic pockets without pressure regulation. A regulating valve controls the force between the longitudinal support and the casing of the roll by setting the pressure in the middle chamber and by setting the pressure in the piston pressure space.

Abstract: A roll, specifically a paper machine press roll, with a hollow rotatable roll body features a roll shell and on at least one of its two ends a hollow roll journal. A guide body which is stationary or fastened to the roll body extends through the interior of the roll body and forms with the roll shell a channel system through which a tempering medium flows. For purposes of using air as tempering medium, a pressure blower and/or a suction blower are connected to the channel system. The channel system and the blower(s) are so dimensioned that an air flow velocity above 10 m/sec will materialize in the channel system.

Abstract: A stationary support device for a paper making machine wire has a movable cover strip, which is formed of a movable support strip and a head strip formed of a hard material on the support strip. The head strip has a leading upstream edge over which the wire slides and has a dewatering surface after the leading edge and which forms a variable angle of inclination with the wire. In the region of its front edge the moveable support strip is connected by a web-groove joint to a rigid support. A bar which is displaceable cross machine is inserted in the rigid support on the rear of the support device. A plurality of obliquely extending grooves are provided in the bar. In each groove there is a slide block which receives the spherical head of a pin. The pin is engaged by its external thread in the internal thread of a square bushing which is fastened in the support strip of the cover strip. The position of the pin can be adjusted parallel to the direction of travel of the wire in the bushing.

Abstract: In the press section of a paper making machine, there is a central roll, a first press roll beneath and a second press roll above the central roll defining respective first and second press nips. The first press nip or both nips may be extended nip presses. A water impervious press belt travels through the first press nip around the central roll and through the second press nip, meeting the central roll before the first nip and leaving the central roll after the second nip. A felt belt conducts the web to be dewatered into the first nip along with the press belt. The felt belt separates from the web after the first nip. Following the second press nip, the press belt carries the web to a place of removal where a dryer wire picks up the web. The distance from the second press nip to the place of removal is at least equal to the circumference of and is preferably greater than the circumference of the central roll.

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 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: An extended nip press for the dewatering of a fiber web has an endless flexible press element, like a press jacket or press belt. A press shoe has a concave slide surface for the flexible press element, and the slide surface is adapted to the curve of a backing roll. The shoe is displaceable toward the backing roll in order to press the pressing element against it. A stationary shoe bed, which is detachably connected to a stationary support, has a depression which is provided with a packing and receives the press shoe to form a pressure chamber so that the shoe bed and the press shoe form a cylinder-piston unit. The press shoe is coupled to the shoe bed by means of at least one connecting element. The connecting element is spring biased with respect to the shoe bed and may itself be flexible or be flexibly moved to permit the radial displacement as well as the tilting of the press shoe relative to the shoe bed.

Abstract: A bearing case for a multiple-row self-aligning antifriction bearing, preferably a self-aligning roller bearing, supports a roll journal and has a circulating oil lubrication system with oil feed line and outlet channel. The discharge point of the feed line is located on the one side of the antifriction bearing while the entrance to the outlet channel is arranged on the other side of the antifriction bearing. Provided between the discharge point of the feed line and the adjacent end wall of the bearing case is a baffle that interacts with a stop ring surrounding the roll journal as a sealing element. The stop ring is movable in radial direction relative to the baffle.

Abstract: A roll, specifically a paper machine press roll, with a hollow rotatable roll body features a roll shell and on at least one of its two ends a hollow roll journal. A guide body which is stationary or fastened to the roll body extends through the interior of the roll body and forms with the roll shell a channel system through which a tempering medium flows. For purposes of using air as tempering medium, a pressure blower and/or a suction blower are connected to the channel system. The channel system and the blower(s) are so dimensioned that an air flow velocity above 10 m/sec will materialize in the channel system.

Abstract: The suction roll of a dryer group is in the path of the web and of the web support belt from an upstream dryer cylinder to a downstream dryer cylinder. The suction roll has an annular roll shell having a plurality of radial holes and being free of stationary inserts at least over the predominant part of the length of the roll shell. A hollow roll journal at at least one end of the suction roll connects vacuum into the suction roll and to the radial holes. In at least some of the holes there are respective deflector pieces. Each extends a short radial distance into the inside of the roll shell over a short radial portion. The deflector piece has a continuous channel which extends radially inward through the hole toward the inside of the roll in a direction substantially parallel to the direction of extension of the hole and the radially inward portion of the channel is curved in the direction contrary to the direction of rotation of the roll shell.

Abstract: An endless flexible press jacket for a press roll, a process for its fabrication and an apparatus upon which it is fabricated. The press jacket comprises a radially inner layer of elastomeric material which is provided with embedded layers of reinforcing yarns, an inner longitudinal layer of yarns extending under tension between the lateral ends of the endless tubular press jacket and a helical winding of peripheral yarns pretensioned and wrapped around the longitudinal yarns. The longitudinal yarns are held pretensioned radially above a casting mandrel and the casting nozzle moves along the axis of the casting mandrel delivering a helix of castable jacket material around the casting mandrel. At the same time, the later peripheral yarns are applied into the longitudinal yarns in the applied jacket material.

Abstract: A stationary support device for the drainage wire screen of a fiber web forming section. The cover ledge over which the drainage screen passes has a front edge which the screen passes and then the drainage surface beneath the wire screen diverges from the wire screen in the wire screen advancing direction. The cover ledge is of hard material. The front part of the cover ledge is supported by a support at a rigid pivot joint. The rearward part of the cover ledge is supported by wedge surface connections for permitting adjustment of the tilt orientation of the cover ledge with respect to the drainage wire. Leaf type clamping springs disposed between the cover ledge and the support, disposed rearwardly of the front joint and disposed forwardly of the wedge surface connections. The clamping leaf springs being connected to the cover ledge by tie rods at the center of the spring and to the support by tie rods at the ends of the springs.