Abstract: A machine for manufacturing a material web, in particular a paper or cardboard web, comprises a drying section that exhibits at least one drying group comprising two rows, including an upper and a bottom row of heatable drying cylinders, which are each assigned a transport belt, which is guided around the drying cylinder and the guide rollers assigned to the drying cylinders in a meandering fashion, whereby the material web is guided in an alternating manner around a drying cylinder of the top row and a drying cylinder of the bottom row and between the drying cylinders in a free stretch, and with at least one first nozzle, serving to transfer the threading strip, projecting a flow of gas essentially against the run direction of the material web. The machine includes a guide device positioned on the material web side opposite the first nozzle, which includes at least a second nozzle projecting a flow of gas essentially in the run direction of the material web.

Abstract: The present invention relates to the dryer section of a paper machine consisting of a number dryer groups having dryer cylinders and one reversal role between each two dryers within a dryer group. The dryer section may have top felted or bottom felted dryer groups. A differential pressure box may be placed between the dryer cylinders and above the reversal roles in a top-felted dryer group and between the dryer cylinders and below reversal roles in a bottom felted dryer group. Between dryer groups the transfer between top felted dryer groups can occur with either an open or closed draw. The transfer between a top felted dryer group and a bottom felted dryer group occurs with an open draw. The size of the draw can be adjustable by making one or both of the guide rolls at the transfer moveable.

Abstract: Dryer section of a machine for producing a material web. The dryer section may include at least one dryer group including a plurality of heatable dryer cylinders so that the material web to be guided around at least a portion of the plurality of heatable dryer cylinders may be guided in a meandering path in a web travel direction. At least one pressing device may be located within the dryer section.

Abstract: A machine for producing a material web, including a paper or cardboard web, having a plurality of cylinders around which the material web is guided in a meandering path together with a conveyor (transport) belt. The machine further includes at least one air conveying device disposed in the transfer region between two cylinders. The air conveying device associates with the free circumference region of a cylinder and aspirates the material web as the material web travels in a path free from contact with the cylinders as the material web travels between two succeeding cylinders. The material web and the conveyor belt are partially wound around the circumference region of the cylinders. According to the invention, the air conveying device only covers certain areas of the free circumference region of the cylinder on which the material web (paper web) winds.

Abstract: Apparatus for controlling widthwise contraction of a conveyed web has opposing first web carrier belts and opposing second web carrier belts forming a generally serpentine transport path for supporting opposite lateral edges of the conveyed web.

Abstract: A dryer section of a paper machine including groups with single-wire draw that include a drying wire guided in a loop and reversing cylinders arranged in the drying-wire loop. Contact drying cylinders are arranged in gaps between the reversing cylinder and the drying wire is guided to press a web against heated faces of the contact drying cylinders. In addition to normal, small-diameter contact drying cylinders, one or more large-diameter contact drying cylinders (the diameter being greater than about 2200 mm and usually in a range from 2200 mm to 3600 mm), is/are used in one or more single-wire draw groups. An impingement-drying/ventilation hood is arranged above the large-diameter contact drying cylinders and extends on a large sector above the contact drying cylinder and above the drying wire and the web running over the cylinder. An impingement-drying/ventilation effect is applied to the drying wire through the impingement-drying/ventilation hoods on the large sector.

Abstract: An air heating and control system, which in one application controls the diameter of a calender roll in the paper making process, includes a row of heater packs proximate to the various zones of the calender roll. Each heater pack has a plurality of electrical heating coils which are at least partially connected in parallel so that failure of one coil does not interrupt power to the remaining coils. Air flowing through the heating coils is heated to a desired temperature and impinges upon the calender roll to expand it as desired. A control system senses a defective coil, which effectively reduces current in a heater pack, and increases the voltage imposed upon that heater pack to again produce the desired power level or heating effect. Thus failure of a heating coil is immediately compensated for.

Abstract: A method and apparatus for correcting the curl in drying and dried paper is presented wherein high velocity hoods are used in combination with drying cylinders. In addition, the use of impingement drying hoods provide a means to correct for variations in the moisture profile of the paper. High velocity hoods can be located in the drying section of a paper machine to compensate for uneven drying by paper cylinders.

Abstract: Dryer section of a machine for manufacturing a material sheet. The dryer section may include at least one dryer cylinder, a plurality of sheet guide rolls, a transport belt for guiding the material sheet in a meandering manner around the at least one dryer cylinder and the plurality of sheet guide rolls, and threads surrounding at least one of the at least one dryer cylinder and the plurality of sheet guide rolls. The threads may be positioned between the material sheet and a surface of the at least one of the at least one dryer cylinder and the plurality of sheet guide rolls.

Abstract: A web finishing section in a paper machine including a dryer section having one or more dryer groups, a calender and a reel-up. The calender is placed at least partly underneath the reel spool storage space of the reel-up so that the reel-up is placed substantially directly after the calender, in which case, the web is passed directly from a calendering nip in the calender onto the reel cylinder or to a substantially short distance from the calender, the web being passed over one guide member that supports and/or spreads the web onto the reel cylinder. The calender includes one or more calendering belts for carrying the web through the calendering nip(s). A method for finishing a web is also described.

Abstract: The present invention is directed to a technique on a continuous drying apparatus for porous web, which comprises a heating cylinder, an impermeable drying band impermeable to air and water, coming into contact with and supporting the surface on the side having no contact with the heating cylinder of the porous web, and a plurality of water lubricating shoe members arranged around the heating cylinder apart a desired distance from the external side of the impermeable drying band, for forming a water screen flow between them and the external surface of the impermeable drying band, whereby an effective drying of the porous web is achieved.

Abstract: A dryer group with single-wire draw in the dryer section of a paper machine including heated drying cylinders having a smooth face against which a paper web to be dried is brought into direct contact, reversing cylinders and a drying-wire guided by guide rolls, the drying cylinders and the reversing cylinders in a loop whereby the drying cylinders are situated outside the wire loop and the reversing cylinders are situated in gaps between the drying cylinders and inside the wire loop of the drying wire. The drying cylinders consist of large cylinders and small cylinders, the diameter D of the large cylinders being larger than the diameter d of the small cylinders. The small cylinders are situated in gaps between adjacent pairs of large cylinders so that their centers of rotation are on a level substantially different from the level of the centers of rotation of the large cylinders.

Abstract: A dust and fiber control device for paper making apparatus is described. The device includes a wall in conjunction with a feed spout for providing a water curtain. The water curtain serves to capture and remove air suspended dust and fiber particles from ambient air. The device is positioned transversely to the motion of a paper web underneath the web between a drying cylinder and a rewinder. The water curtain device is utilized in conjunction with air flow devices for assisting in controlling the collection of air suspended dust and fiber particles from the ambient air.

Abstract: A dryer section of a paper machine which is provided with at least one intermediate calendering nip and includes several successively arranged wire groups. The dryer section primarily or exclusively has groups with single-wire draw in which heated drying cylinders are arranged in an upper row and reversing suction cylinders or reversing suction rolls are arranged in a lower row below the upper row. The groups with single-wire draw also have a drying wire which runs along a meandering path over the drying cylinders and reversing suction cylinders or rolls so that the reversing suction cylinders remain inside the loop of the drying wire. A calender roll is arranged in opposed relationship to a drying cylinder in one or more of the single-wire draw groups in a sector which the first face of the web is exposed to thereby define a calendering nip therewith.

Abstract: A papermaking machine including a forming section for forming a paper web, a press section for pressing water from the paper web, and a dryer for drying the paper web is disclosed. The dryer includes a wet end for drying the paper web to at least about 60 percent solids and a dry end for further drying the paper web. The dry end includes at least one series of alternating dryer cylinders and vacuum rolls. A dryer felt transports the paper web as the dryer felt travels about each dryer cylinder and each vacuum roll of the series. In one disclosed embodiment, at least one of the vacuum rolls receives a vacuum of at least about one inch water column (1.5 kilo-pascals, "kPa") to restrain the web as it dries. A method for manufacturing a paper web while restraining it by using the dryer apparatus described above is also disclosed.

Abstract: A method for controlling the curl of paper in which steam treatment and/or moistening of the paper web is/are carried out after the calendering process being performed in the calender. In processes in which calendering is not employed, the curl is controlled in connection with a machine reel-up or in process steps carried out after the machine reel-up. A paper or board machine applying the method includes a headbox, a former, a press, a dryer section and steam boxes, moistening devices, an IR dryer and/or equivalent curl control devices. The steam boxes, moistening devices, IR dryers and/or equivalent curl control devices for the control of the curl are arranged after the calender or, if no calender is employed, in connection with a machine reel-up or a finishing process carried out after the machine reel-up.

Abstract: An apparatus for stabilizing a low-strength sheet having a width and a top surface and moving in a first direction at a rate sufficient to entrain air. The apparatus includes an airfoil adapted to extend along the top surface of the sheet. The airfoil, in turn, includes:a bottom surface adapted to extend along a portion of the top surface of the sheet;a first surface extending a first distance from the bottom surface at a first juncture;a second surface extending a second distance from the bottom surface at a second juncture; anda top surface extending from the first surface at a third juncture to the second surface at a fourth juncture. The first distance in general is less than the second distance.

Abstract: A process and device for producing a pulp web utilizes several independently driven aggregates (i.e., discrete groups) to attain a median web dry content of, e.g., 60%. The number of driven aggregates may depend upon an initial wet strength of the wet pulp web. The relationship is such that when the initial wet strength is relatively high, the number of drier groups is small and when the initial wet strength is relatively low, the number of drier groups is large. However, each drier group includes only a few drier cylinders. The first drier group may include either one or two cylinders, and each subsequent drier group may include at least one drier cylinder more than the adjacent upstream drier group.

Abstract: A dryer roll of a paper machine is provided with a doctor assembly, including a doctor blade. A contaminant removal assembly includes a hood mounted in a cantilevered manner to a support extending parallel to the axis of rotation of the dryer roll, and the hood extends downstream from the support and is in sealing contact with the upper surface of the doctor blade to form a channel between the doctor blade, the hood, and the surface of the dryer roll. Air amplifiers are provided at both ends of the hood for creating an airstream extending longitudinally of the hood and exhausting at one end thereof to remove fuzz picked up by the doctor blade on the surface of the dryer roll.

Abstract: A method and arrangement for evaporation drying of a paper web in which the web is dried in three successive stages I, II and III that are carried out in the direction of progress of the web as follows: in the first stage (I), the web is heated in a short section in the machine direction quickly to a temperature of 55.degree. C. to 85.degree. C.

Abstract: A drying unit in a dryer section of a paper or board machine including a drying wire guided in a loop, a large-diameter impingement-drying and/or through-drying cylinder arranged inside the drying-wire loop and smaller diameter smooth-faced heated contact-drying cylinders arranged on top of the large cylinder and/or in the vicinity thereof and at both sides thereof. The impingement-drying and/or through-drying cylinder is placed in a space below the floor level of the paper machine hall and provided with an openable and closable blow hood so that the removal of broke out of connection with the hood takes place substantially by the force of gravity. The central axes of the contact-drying cylinders placed in the vicinity of the large cylinder are placed in the vicinity of, or above, the floor level of the paper machine hall. A curve sector of the paper web on the outer face of the drying wire over the large cylinder greater than about 180.degree..

Abstract: A machine is proposed for the production of a material sheet, in particular a paper or cardboard sheet, with a dryer section which exhibits at least one double-row dryer group consisting of two rows of heated dryer cylinders, each of which has been assigned a transport belt circulating in a meandering fashion around the dryer cylinders of one row and the deflection rolls assigned to the dryer cylinders, thereby pressing the material sheet against the surface of the dryer cylinders, and having a drive mechanism consisting of at least one motor assigned to each row of dryer cylinders of a double-row dryer group, which causes a rotation of the dryer cylinders and deflection rolls as well as a circulation of the transport belts of the dryer section, in which the drive mechanism is designed such that the rotational speed of the two rows of dryer cylinders within the double-row dryer group can be regulated independently of one another.

Abstract: A dry end of a paper machine and a method for drying paper in which a paper web to be dried is passed from a press section of the paper machine into a forward dryer section including only single-wire groups with normal single-wire draw. The web is dried from the side of its bottom face in the dryer groups in the forward dryer section. From the forward dryer section, the web is passed into a finishing section in which the web is coated/surface-sized by a coating/surface-sizing device and then dried in an after-dryer by passing through at least one dryer group that applies a normal single-wire draw. Thereafter, the web is calendered and passed to a reeling station. Curling of the web is controlled by the operation or construction of components and/or by assemblies and combinations formed out of these components provided in connection with the forward dryer section and/or the finishing section.

Abstract: A roll for a paper machine, in particular for a paper drying device, including an axle on whose support the roll revolves, and a surface construction connected to the axle by support members. The openness of the surface construction of the roll is higher than about 10%, preferably higher than about 20%, so that when the roll an effect is produced that sucks air inward into the roll whereby a flow of air through the roll arises. Also, a single-wire draw dryer group for a paper machine having two contact-drying cylinders and one reversing roll wherein a web to be dried is guided on support of a drying wire meandering from one drying cylinder onto the reversing roll and then onto the other drying cylinder so that on the drying cylinders, the web remains between the cylinder face and the drying wire and on the reversing cylinder, the web is situated at the side of the outside curve.

Abstract: A drying section apparatus is disclosed for drying a web of paper. The apparatus includes a size press for applying size to at least one side of the web. A single tier dryer is disposed downstream relative to the size press for drying the web. The single tier dryer includes a plurality of dryer cylinders and a plurality of vacuum rolls. Each of the vacuum rolls is disposed between adjacent dryer cylinders of the plurality of dryer cylinders. A dryer felt extends around at least one of the dryer cylinders. The arrangement is such that at least one of the dryer cylinders is top felted for permitting downward removal of broke. An air cap is disposed above at least one of the dryer cylinders for blowing air through the felt for drying the web disposed between the dryer cylinder and the felt. The arrangement is such that both sides of the web are dried during passage of the web through the single tier dryer.

Abstract: The invention relates to a dry end for drying a material web, in particular a paper or cardboard web, having at least one drying group with a plurality of drying cylinders and web guiding rollers and at least one nozzle device for transporting the threading part of the material web along a winding path by means of at least one conveyor band. The dry end is characterised in that groups of at least two nozzle devices (17, 19, 21) located at the same side of the material web (11) follow each other in the direction of transport of the material web (11).

Abstract: A device for transferring a web of paper in the drying section of a paper making machine from one dryer to the next without any open draw. The device is a stationary vacuum bridge that is defined by a pair of walls, and includes rollers on one of the walls for the felt of the drying section to roll thereon.

Abstract: A method in a dryer section of a paper or board machine for controlling curl of paper, in which steam treatment and/or moistening of the paper web is/are employed. The operations carried out in order to control the curl of the paper web are carried out in a number of stages when the web temperature is, during at least one stage, lower than 85.degree. C., preferably lower than 75.degree. C., and when the dry solids content of the web is in the range of K1-K2, wherein K1 is the ultimate dry solids content of the web -7% and K2 is the ultimate dry solids content +3%. The paper or board machine includes at least a headbox, a former, a press, and a dryer section in steam boxes or moistening devices are employed for control of the curl. There are at least two curl regulation devices to enable regulation of the curl in a number of stages, and/or the curl regulation devices are arranged to operate in an area in which the web temperature is, during at least one stage lower than 85.degree. C., preferably lower than 75.

Abstract: An after-dryer and method for drying a surface-treated paper web in an after-dryer of a paper machine in which the web is first finished in a finishing section, i.e., surface-sized or coated, by a finishing device and then dried. In the after-dryer, the paper web is dried in at least one dryer group that makes use of single-wire draw and at the same time, the paper web is dried by an impingement-drying equipment arranged in connection with at least one cylinder or roll in the single-wire dryer group.

Abstract: A dryer section is proposed, which is part of a machine for producing a material web, in particular a paper or cardboard web, with at least one dryer group that has a number of heatable dryer cylinders around which the material web is guided in a meandering path. The dryer section is distinguished by virtue of the fact that at least one pressing device (31) is provided inside the dryer section (1).

Abstract: A web finishing section in a paper machine including a dryer section having one or more dryer groups, a calender and a reel-up. The calender is placed at least partly underneath the reel spool storage space of the reel-up so that the reel-up is placed substantially directly after the calender, in which case, the web is passed directly from the calendering nip onto the reel cylinder or to a substantially short distance from the calender, the web being passed over one guide member that supports and/or spreads the web onto the reel cylinder. A method for finishing a web is also described.

Abstract: Machine for manufacturing a material sheet and method of guiding the material sheet through the machine. The machine may include a dryer section including at least one dryer group having a plurality of dryer cylinders. Centers of a first plurality of the plurality of dryer cylinders may be arranged on an upper level and centers of a second plurality of the plurality of dryer cylinders may be arranged on a lower level spaced a distance from the upper level. A top felt may be associated with at least one of the first plurality of dryer cylinders and a bottom felt associated with at least one of the second plurality of dryer cylinders. The machine may also include a meandering run path for the material sheet through the at least one dryer group, the material sheet being guided in the meandering run path by the top and bottom felts, and at least one transition area between the plurality of dryer cylinders.

Abstract: The dryer section in a papermaking machine has a single tier of all top felted dryer rolls six to nine feet in diameter. Air caps are employed over the dryer rolls to simultaneously dry both sides of the web to prevent curl and to increase drying rates. The air caps employ blown air at a temperature of 250-900 degrees Fahrenheit and air speeds of 8,000-40,000 feet per minute. The dryer fabric employed is foraminous with a permeability of between 300-1,200 cubic feet per minute per square foot and is designed to withstand peak temperatures of up to 900 degrees Fahrenheit and average temperatures of between 500-600 degrees Fahrenheit. A single transfer roll, or more advantageously, two grooved vacuum rolls in a vacuum box are disposed between the dryer rolls to maximize the circumferential wrap of the web and, at the same time, support and transport the web between dryer rolls.

Abstract: A drying section in a papermaking machine has a first section with a series of single-tiered drying cylinders having vacuum transfer rolls with external vacuum chambers therebetween for improving web runnability, and a second dryer section with a series of single-tiered drying cylinders having movable vacuum transfer rolls disposed therebetween for providing improved cross-directional web shrinkage restraint.

Abstract: Machine for producing a material web, e.g., paper or cardboard, that may include a dryer section with at least one dryer group and the at least one dryer group may have at least one dryer cylinder, a dryer screen, and a metal belt. The machine may also include a cooling device associated with the metal belt. The material web, the dryer screen and the metal belt may be guided in a meandering path around an outside of the at least one dryer cylinder, and the dryer screen may be positioned between the material web and the metal belt. Further, at least one of the metal belt and the dryer screen may be intensely prestressed.

Abstract: A method for drying a surface-treated paper web or equivalent in an after-dryer of a paper machine in which the paper web is first finished in a finishing section, e.g., surface-sized or coated, by a finishing device and then dried. In the after-dryer, the paper web is dried in at least one dryer group employing a normal single-wire draw and, in connection with or after the drying, the paper web is treated by at least one device in order to compensate for a tendency of curling of the paper web. The after-dryer is arranged after the finishing device and includes at least one dryer group that applies a normal single-wire draw so as to dry the paper web and one or more devices for compensating for a tendency of curling of the paper web.

Abstract: A dryer section employs top-felted and bottom-felted dryer sections each comprised of a single steam-heated drying cylinder with a diameter of about 12 feet. The web is transferred between drying cylinders by a two vacuum roll transfer without an open draw. The dryer fabric wrap on the large dryer cylinders is over 270 degrees resulting in large drying capability per dryer roll. Because each large dryer is followed by another large dryer roll which dries the opposite side of the web, uniformity of drying is maintained. Each dryer cylinder may have its own dryer fabric stretcher and guides. Alternatively, individual dryer fabrics service multiple top-felted dryers and bottom-felted dryers respectively. The web is constrained approximately 96 percent of the time as it passes through the is dryer section. The dryer section can achieve 2.9 inches of dryer surface in the machine direction for every inch of dryer section.

Abstract: A dryer section of a paper machine which is provided with at least one intermediate calendering nip and includes several successively arranged wire groups. The dryer section primarily or exclusively has groups with single-wire draw in which heated drying cylinders are arranged in an upper row and reversing suction cylinders or reversing suction rolls are arranged in a lower row below the upper row. The groups with single-wire draw also have a drying wire which runs along a meandering path over the drying cylinders and reversing suction cylinders or rolls so that the reversing suction cylinders remain inside the loop of the drying wire. Two calender rolls are arranged to form the calendering nip through which a paper web to be dried is passed, and thus calendered inside the dryer section, immediately preceding or following or within one or more of the dryer groups of the dryer section.

Abstract: A dryer section of a paper machine which is provided with at least one intermediate calendering nip and includes several successively arranged wire groups. The dryer section primarily or exclusively has groups with single-wire draw in which heated drying cylinders are arranged in an upper row and reversing suction cylinders or reversing suction rolls are arranged in a lower row below the upper row. The groups with single-wire draw also have a drying wire which runs along a meandering path over the drying cylinders and reversing suction cylinders or rolls so that the reversing suction cylinders remain inside the loop of the drying wire.

Abstract: The invention is a paper making machine and a method of making paper. The machine includes a section for forming a wet paper web having first and second sides and a dryer for drying the wet paper web. At least a first portion of the dryer is capable of preferentially drying the first side of the wet paper web to a dryness level of at least about 70% solids. In a variation of the paper making machine, the first portion of the dryer is capable of preferentially drying the first side of the wet paper web to a dryness level of at least about M, as represented by the formula:M=101-0.246 (WRV)in which WRV is the water retention value of the web. The method for drying a web of paper includes a forming step and a drying step. The forming step is carried out by forming a wet paper web having first and second sides.

Abstract: A machine for the production of a continuous web, particularly of paper or cardboard, may include a plurality of rolls around which a continuous web may be guided. The machine may also include a blocking device, arranged in a vicinity of an edge of the continuous web, to prevent turbulences and arranged at a predetermined distance from a free stretch formed by the continuous web traveling between two adjacent rolls. The blocking device may extend along a longitudinal portion of the free stretch, i.e, in a transport direction of the continuous web, and/or may extend across a portion of the free stretch transverse to the transport direction of the continuous web.

Abstract: A single tier dryer system has dryer rolls with a reversing roll positioned between each pair to transfer and wrap the dryer felt and paper web against the next dryer roll. A vacuum box is positioned between the dryer rolls and over the reversing roll to hold the web on the dryer felt by vacuum. Threading of a tail from the web is accomplished by blowing the web tail off a first dryer roll's surface with a jet of air positioned adjacent to the position on the dryer roll where the dryer felt leaves the dryer roll's surface. The vacuum box is divided by a baffle to isolate a portion of the vacuum box near the front of the dryer rolls, and a damper is positioned within the reversing roll to increase the vacuum in the isolated portion of the vacuum box to facilitate threading of the tail.

Abstract: When drying a paper web (4) in a dryer section (1) of a paper machine provided with drying cylinders (2, 3) and drying wires (5, 6), shrinkage of the paper web in cross direction is counteracted by applying forces at its edge portions (11). According to the invention partial vacuum is maintained along the edge portions of the web within substantially the entire free draw (10) and is applied from the side of the drying wire (5, 6) facing away from the web (4) so that the web is sucked firmly against the drying wire by forces greater than the contracting forces acting in cross direction, thereby counteracting shrinking, said partial vacuum being set within the interval 0.1-0.8 bar, preferably 0.2-0.5 bar.

Abstract: A drying section for a paper making machine includes a larger number of dryer sections, fewer dryers in each dryer section, and provisions for driving many of the dryers individually. The average number of dryers per dryer section is less than five and preferably less than four. By providing a small number of dryers per dryer section and driving many of the dryers individually, it is possible to more precisely compensate for stretching of the paper web in the initial stages of the drying process and to more precisely compensate for shrinkage of the paper web during the latter stages of the drying process.

Abstract: A method and device for washing a drying wire in a dryer group in a dryer section of a paper or board machine in which the drying wire is guided by drying cylinders, reversing rolls and guide rolls. A liquid jet is directed at the drying wire at a location after a first one of the drying cylinders in the dryer group and before a last one of the drying cylinders in the dryer group and/or a location on a downward run of the drying wire from one of the drying cylinders. The washing device includes a spray device for providing the liquid jet and possibly an air blow device for blowing air at the drying wire after the liquid jet in order to dry the drying wire.

Abstract: A method and device for drying a paper web in a dryer section having a number of successive dryer groups with a single-wire draw, and being situated after a press section of the paper machine. Each dryer group includes contact-drying cylinders arranged in a first row and reversing suction cylinders or equivalent suction rolls arranged in a second row, the rows being horizontal, diagonal or vertical rows. The paper web is dried by contact-drying cylinders from the side of its lower face across the entire length of the dryer section. The paper web is passed as a closed draw from one dryer group to the next group, and the paper web is guided, while it runs on the drying wire at the side of the outside curve, by the reversing suction cylinders having a curve radius selected in a range from about 250 mm to about 1000 mm.

Abstract: Machine for manufacturing a web that may include a dryer section having a plurality of dryer cylinders and a plurality of guide rolls, a transport belt that guides the web through the dryer section in a meandering path, a moistening apparatus, and a controlling device. The controlling device may include a device for detecting a web break and a device that activates the moistening apparatus to cool the dryer cylinders in response to the detected web break.

Abstract: Device for drying a web in a two-screen dryer section. The device may include a plurality of heatable dryer cylinders arranged in vertically spaced upper and lower cylinder rows, an upper endless screen associated with the upper cylinder row and a bottom endless screen associated with the bottom cylinder row, and a screen guide roll associated with one of the upper and lower endless screens. A shaft may be formed between adjacent cylinders in a cylinder row and bounded by one of the upper and lower endless screens guided around the adjacent cylinders and the screen guide roll. An air box and a blowing device may be positioned within the shaft, and the blowing device may be arranged in a region of separation between the screen and the screen guide roll to direct an air flow through the screen. The device may also include a longitudinal sealing strip coupled to a surface of the screen guide roll in a vicinity of the region of separation.

Abstract: A method for cutting the leader of the web in a paper or board machine in the dryer section of the machine by a jet of pressurized water. The web is placed against the drying wire when it is being cut, and the jet is directed at the web from the free side of the web. The water jet pressure used is from about 40 bar to about 400 bar, preferably from about 100 bar to about 350 bar, which is produced by an ordinary pressure washer.

Abstract: The top and bottom felts at the web transfer between two dryer sections in a single tier papermaking dryer are spaced by pivoting the vacuum roll over which the felt and web move. The vacuum roll is mounted to two pivot arms which are driven by inflatable air rides to alternately incline the roll toward the downstream felt, forming a sandwich of the two felts and the web, and to a spaced position. The short motion of the vacuum roll allows standard felt stretchers to be used, and permits rapid adjustment of the felt spacing.