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: A suction device for a machine to produce a fibrous pulp web is provided that includes a suction unit extending transverse to a web run direction over a width of the web, a vacuum source coupled to the end of the suction unit, and a plurality of suction openings distributed over the web width, where the plurality of suction openings form an entire suction zone extending over the width of the web, and where the entire suction zone includes a plurality of partial suction zones successively arranged transverse to the web run direction.

Abstract: Apparatus for drying a web and modifying the moisture profile of the web includes a housing within which is disposed a through air dryer roll supporting a web. A fan located at an end of the roll causes flow of air through the web while the web is on the roll and through openings in the roll into the interior of the roll. The air then flows through a roll end and into the interior of the housing externally of the roll for recirculation back into the roll interior through the web and through the openings in the roll. Heaters heat the flowing air and are used to modify the moisture profile of the web. The apparatus is very compact.

Abstract: A wet and/or dry finishing machine for fabrics in rope or open-width form comprising a treatment tank in which a transporting means is installed for the fabric, for example in endless-loop form, the transporting means drawing the fabric from the base of the tank and feeding it against a counteracting fuller element, in proximity to at least one base wall portion of the tank there being positioned a duct provided with apertures and through which an air stream is circulated, a portion of the fabric bearing on the top of the duct. This improves drying and shortens the drying time.

Abstract: Apparatus and method for drying a wet web and modifying the moisture profile of the web. A plurality of gas burners are located within the interior of a through air dryer hood to variably heat air passing through the hood interior before it contacts a wet web on a through air dryer web support. The flowing air within the hood interior is divided into air flow portions directed toward different incremental width portions of the wet web. The burners are separately controlled to vary the heat of the individual flowing air portions to provide a uniform web moisture profile.

Abstract: A steam heated web processing roll includes a fully enclosed steam and condensate flow-through system which maintains the roll end walls at approximately the same operating temperature as the functional cylindrical outer roll shell at normal rotational speeds. The closed loop system also assists in purging non-condensible gases from the steam path. At low roll speeds or when the roll is stopped, a valving system closes all of the condensate return paths except one or more of the lowermost paths from which condensate pooling in a sump at the bottom of the roll is withdrawn. This prevents undesirable cooling of the lower portion of the roll as compared to the remaining portion, thereby reducing the possibility of bowing of the roll by thermal distortion.

Abstract: A dryer section in a papermaking machine has two reversing rolls to form a pocket between each pair of dryers in a dryer tier. The first reversing roll is a vacuum roll and the second reversing roll is a grooved roll. A blow box is disposed between the two rolls, the blow box provides suction for the grooved roll and provides vacuum which restrains a web on the dryer fabric as it travels between the first and the second rolls. The blow box also provides a supply of make-up air which extends in a cross machine direction along the pocket formed by the two reversing rolls. The blow box also supports a pivoting foil which is positioned against the dryer fabric as it moves from a first dryer, towards the first reversing roll. The foil defines a region of low pressure which restrains the web as it travels between the first dryer and the first reversing roll.

Abstract: A machine for producing a material web, e.g., a paper or cardboard web, with a dryer section including at least one dryer group having a plurality of dryer cylinders and a plurality of web guide rolls, e.g., suction web guide rolls. At least one web guide roll, and preferably all, may be associated with an external suction box. Further, a jacket of the at least one web guide roll may include a plurality of through openings and at least one groove formed in an outer surface of the jacket. A predetermined number, and preferably all, of the through openings may be coupled with a bottom portion of the at least one groove to enable the external suction box to suction the at least one web guide roll.

Abstract: The present invention is directed to a coaxial waveguide applicator for an electromagnetic wave-activated sorption system which comprises at least one sorber having a metallic tubular housing defining an outer conductor and first and second ends which are sealed to define an enclosure within the outer conductor; a sorbate/sorbent compound located within the enclosure; the sorber including a port through which a sorbate may be communicated into or out of the enclosure; a metallic inner conductor extending into the outer conductor and parallel to the longitudinal axis of the sorber; an electromagnetic wave generator; and a waveguide for coupling electromagnetic waves generated by the electromagnetic wave generator to the inner and outer conductors; wherein electromagnetic waves transmitted by the electromagnetic wave generator are propagated through the enclosure by the inner and outer conductors to desorb the sorbate from the sorbate/sorbent compound.

Abstract: A paper drying apparatus including a first rotatable drum, wherein the first rotatable drum has an inner perimeter and an outer perimeter and a second rotatable drum having an inner perimeter and an outer perimeter. A fabric sheet for carrying a paper web is provided, wherein the fabric sheet passes around the outer perimeter of the first rotatable drum and proceeds to next pass around the outer perimeter of the second rotatable drum. As the fabric sheet conveys the paper web around the first rotatable drum, a drying air is applied to the paper web in a direction from the inner perimeter of the first rotatable drum toward the outer perimeter of the first rotatable drum, further passing through the paper web. As the fabric sheet and paper web proceed around the second rotatable drum, a drying air is applied to the paper web in a direction from the outer perimeter of the second rotatable drum toward the inner perimeter of the second rotatable drum, further passing through the paper web in a similar direction.

Abstract: The invention is directed to a drying section of a paper machine for drying a fiber web. The drying section includes a plurality of drying groups, with each drying group having a plurality of heatable drying cylinders and a continuous hold-down belt. The hold-down belt has a longitudinal tension which biases the fiber web against the drying cylinders. The plurality of drying groups include at least one high-pressure group comprising a single-row drying group having one row of drying cylinders and one row of corresponding deflection rolls. The high-pressure group has a corresponding hold-down belt with a longitudinal tension which is at least 10 kN/m.

Abstract: A device for washing and removing liquid on a gauze conveyor for conveying products, the gauze conveyor having an upper side for carrying products and being provided with link portions and having a gauze pattern. The device having means for removing liquid on the upper side of the gauze conveyor and being formed by a hollow, rotatable roll which is provided with rows of separate projecting teeth, said rows extending axially on the roll, the teeth fitting into the gauze pattern and the link portions being enclosable by the teeth. The roll has holes between the teeth which holes extend into the cavity of the roll.

Abstract: A drying section for drying a traveling web of paper, which has successive drying groups each having drying cylinders, a felt or wire belt supporting the traveling web and resting against the drying cylinders, and guide rolls serving for the guiding of the web to be dried and of the felt or wire belt. The guide rolls are so arranged that the traveling web is guided in meandering form in the transfer region between two successive drying cylinders associated with different felt or wire belts. The transfer region is between the felts of two successive drying groups or the transfer region is between two felts in the two rows of a two tier drying group.

Abstract: Apparatus for drying a wet web, such as a wet paper web, includes a through air dryer roll. A rotatable fan member having fan blades is located within the through air dryer roll interior at one end of the through air dryer roll. Rotation of the fan member causes air flow through a web on the through air dryer roll, through openings of the through air dryer roll into the through air dryer roll interior, through the end of the through air dryer roll accommodating the fan member, and through an air flow passageway to the exterior of the through air dryer roll.

Abstract: Apparatus for distributing a heating medium, such as steam or hot air, to a paper web or calendar roll in sheet making machinery includes a removable profile screen to permit easy cleaning and maintenance. The apparatus comprises an elongated chamber to receive steam or hot air from a supply source with a front wall adapted to receive a removable screen. The removable screen is flexible and defines at least a portion of the front wall conforming generally to the shape of the adjacent surface to be heated. The screen member has a plurality of apertures through which the heating medium is forced to heat the surface. The screen is removably mounted to the apparatus by clip members.

Abstract: Disclosed is a method for reducing the moisture content of a paper web in a papermaking process from in the range of 10% to 32% dry to the range of 33% to 50% dry wherein the embryonic web is supported on a knuckled through drier fabric and lightly pressed between the knuckled through drier fabric and a capillary membrane of a capillary dewatering roll. The capillary membrane has capillary pores therethrough which have a substantially straight through, non-tortuous path with a pore aspect ratio of from about 2 to about 20. A vacuum is drawn within the capillary dewatering roll which is not greater than the negative capillary suction pressure of the capillary pores.

Abstract: A new dryer section or an existing dryer section of the two tier double-felted type has air caps disposed over the upper dryer rolls to simultaneously dry both sides of the web to increase drying rates. The heated pressurized air is blown through multiple air impingement holes in the air cap nozzle plates to impinge the web at a temperature of 500-900 degrees Fahrenheit and air speeds of 20,000-40,000 feet per minute. The dryer fabric employed is foraminous with a permeability of between 400-1,200 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. The design of the air caps utilizes recirculation of the blowing air to control drying rates.

Abstract: A suction drum dryer, for knitted fabrics and the like, is provided with an adjustable width bellows mechanism for masking side margins of the drums not occupied by the fabric web. Ambient air draw into the suction drums is thus caused to flow substantially exclusively through the material to be processed. Significantly improved operating efficiencies are realized, as well as significantly higher production output from a given piece of equipment.

Abstract: A device for removing liquid on a gauze conveyor for conveying products, the gauze conveyor having an upper side for carrying products and being provided with link portions and having a gauze pattern. The device having means for removing liquid on the upper side of the gauze conveyor by extraction said means being placed directly under the gauze conveyor and being formed by a hollow, rotatable roll which is provided with rows of separate projecting teeth, said rows extending axially on the roll, the teeth fitting into the gauze pattern and the link portions being enclosable by the teeth. The roll has holes between the teeth which holes extend into the cavity of the roll.

Abstract: A method and device for drying a paper web wherein the paper web is supported on a drying wire without long open draws of the web. The paper web is contact-dried by pressing it with the drying wire onto a face of a contact-drying cylinder whose diameter is greater than about 1.5 m on a sector b whose magnitude is greater than about 180.degree.. The web is evaporation-dried as blowing-on drying and/or as through-drying by means of high-velocity drying-gas jets applied to the web on the drying wire on the face of the following large-diameter cylinder whose diameter is greater than about 2 m on a sector a having a magnitude greater than about 180.degree. while the web is on the side of the outside curve. The web to be dried is passed over a sector c of the suction roll which is subjected to negative pressure while the web is supported on the drying wire at the side of the outside curve. The magnitude of the sector of the suction roll has a magnitude greater than about 160.degree.

Abstract: An apparatus for drying a wet sheet material such as a paper web is presented. The apparatus is provided with a suitable number of dryer cylinders operating in conjunction with a plurality of steam blast ports disposed adjacent to the dryer cylinders. A vertically movable canopy hood and a middle hood having sheet entry/exit opening and a door opening device are provided. The wet sheet material is held between two endless fabric belts, and passed through the dryer cylinders alternatively via suction fabric rolls, fabric rolls and fabric tension rolls. The drying process is carried out in an atmosphere of superheated steam of over 100.degree. C. inside the canopy hood and the middle hood, and the steam generated from the wet sheets is recirculated through an exhaust screen, a super heated steam circulating fan, an adiabatic compressor and a supply duct. Another atmosphere of heated moist air having a dew point of at least 80.degree. C. is also employed.

Abstract: A vacuum roll apparatus is disclosed for transferring a web supported on a dryer felt from a first to a second drying cylinder of a dryer section. The apparatus includes a rotatable perforate shell having a first and a second end, the shell defining a cavity which extends from the first to the second end of the shell. The arrangement is such that the dryer felt extends from the first dryer around the perforate shell to the second dryer with the web extending contiguously with the dryer felt, and the dryer felt being disposed between the shell and the web. At least one fin is rigidly secured to the shell and is disposed within the cavity such that when the shell is rotated, the fin generates a flow of air through the perforate shell towards the cavity for drawing the web into close conformity with the dryer felt during movement thereof around the vacuum roll apparatus so that the web is restrained against cross-machine directional shrinkage.

Abstract: A device for diverting sheet, web or mat material treated continuously uses an air cushion (6) formed about a cylindrical surface (4). Infrared transmitters (7), whose radiation is directed to a portion of the material (1) being diverted, are provided in or under the cylindrical surface (4), in addition to the air-blowing means (5) generating the air cushion (6). The same volume therefore houses means for diverting the material (1) and means for heating it, especially in order to dry it. At the same time that the blown air flow generates the air cushion (6), it also cools the infrared transmitters (7). Application, in particular, in the manufacture, transformation and treatment of materials such paper, fabric and synthetic film.

Abstract: In a roll for a paper-making machine, a torque which is needed for rotating the roll is reduced and the drive power and a running cost are reduced. A hollow perforated roll in the paper-making machine is rotatably mounted on a bearing housing via a bearing. A cylindrical stationary center shaft extends in an axial direction through a center of the roll and has a perforated circumferential surface. At least two fins extending in an axial direction are mounted on an outer circumferential surface of the center shaft within the hollow interior of the roll, their outer edges being spaced from the inner circumferential surface of the perforated roll. Radially extending disc-like fins are also mounted on the outer circumferential surface of the center shaft perpendicular to an axis of the center shaft with their outer circumferential edges being spaced with a slight gap from the inner circumferential surface of the perforated roll.

Abstract: A limiting orifice through-air-drying apparatus for papermaking or other absorbent embryonic webs. The apparatus has a first zone and a second zone. The first zone is maintained at a differential pressure less than the breakthrough pressure, while the second zone is maintained at a differential pressure greater than the breakthrough pressure. The residence time of the embryonic web to be dried with the apparatus is maintained at preferably less than 35 milliseconds on the first zone. Using the dual zone system described above, the overall energy required to run the apparatus can be reduced.

Abstract: In the initial region of the dryer section at least one of the dryer groups (23) is developed as a single-felt dryer group in which a single endless felt (F) and the web (9) travel alternately over cylinders (73) and guide suction rolls (73'). In the final region of the dryer section there is present at least one double-felt dryer group (24) in which a web (9) travels alternately over lower (74) and upper (74') cylinders. The single-felt group (23) has an automatic ropeless tail guide device (76, 79) for the threading of the so-called tail. In the double-felt dryer group (24) an automatic ropeless tail guide device (77, 78) is also present.

Abstract: limiting orifice through-air-drying apparatus for papermaking or other absorbent embryonic webs. The apparatus has a first zone and a second zone. The first zone is maintained at a differential pressure less than the breakthrough pressure, while the second zone is maintained at a differential pressure greater than the breakthrough pressure. The residence time of the embryonic web to be dried with the apparatus is maintained at preferably less than 35 milliseconds on the first zone. Using the dual zone system described above, the overall energy required to run the apparatus can be reduced.

Abstract: Apparatus and method for drying a fibrous web. The apparatus comprises a plurality of drying cylinders arranged in groups from a first group to a last group, the web passing sequentially from the first group to the last group, each group having a single felt, the drying cylinders having vacuum transfer rolls arranged therebetween for guiding the fibrous web from one drying cylinder to the next drying cylinder, the vacuum transfer rolls being coupled to a vacuum source by a vacuum duct system, the duct system providing vacuum to the vacuum transfer rolls such that the vacuum level decreases from the first group to the last group. The vacuum level is preferably below about 1500 Pa, and in particular, in the range of about 100 to 1000 Pa.

Abstract: An apparatus and method for drying a wet sheet material such as a paper web is presented. The apparatus is provided with a suitable number of dryer cylinders operating in conjunction with a plurality of steam blast ports disposed adjacent to the dryer cylinders. A vertically movable canopy hood and a middle hood having sheet entry/exit opening and a door opening device are provided. The wet sheet material is held between two endless fabric belts, and passed through the dryer cylinders alternatively via suction fabric rolls, fabric rolls and fabric tension rolls. The drying process is carried out in an atmosphere of superheated steam of over 100.degree. C. inside the canopy hood and the middle hood, and the steam generated from the wet sheets is recirculated through an exhaust screen, a super heated steam circulating fan, an adiabatic compressor and a supply duct. Another atmosphere of heated moist air having a dew point of at least 80.degree. C. is also employed.

Abstract: A single tier drying section apparatus is disclosed for drying a web of paper. The drying section includes a first and a second dryer which are disposed in a single tier for drying the web. A vacuum roll is disposed closely adjacent to and between the first and second dryers for guiding the web from the first to the second dryer. The vacuum roll includes a rotatable roll shell having a first and a second end. The shell defines an outer surface and an internal chamber which extends between the first and the second end of the shell. The shell defines a plurality of channels with each channel extending from the chamber to the outer surface such that the chamber is disposed in fluid communication with the outer surface. A vane mechanism is disposed within the chamber for evacuating the chamber. The arrangement is such that a flow of air flows towards the chamber through the plurality of channels for drawing the web into close conformity with the dryer felt when the web extends around the vacuum roll.

Abstract: A vacuum roll apparatus is disclosed for transferring a web supported on a dryer felt from a first to a second drying cylinder of a dryer section. The apparatus includes a rotatable perforate shell having a first and a second end, the shell defining a cavity which extends from the first to the second end of the shell. The arrangement is such that the dryer felt extends from the first dryer around the perforate shell to the second dryer with the web extending contiguously with the dryer felt, and the dryer felt being disposed between the shell and the web. At least one fin is rigidly secured to the shell and is disposed within the cavity such that when the shell is rotated, the fin generates a flow of air through the perforate shell towards the cavity for drawing the web into close conformity with the dryer felt during movement thereof around the vacuum roll apparatus so that the web is restrained against cross-machine directional shrinkage.

Abstract: A limiting orifice through-air-drying apparatus for papermaking or other absorbent embryonic webs. The apparatus has a first zone and a second zone. The first zone is maintained at a differential pressure less than the breakthrough pressure, while the second zone is maintained at a differential pressure greater than the breakthrough pressure. The residence time of the embryonic web to be dried with the apparatus is maintained at preferably less than 35 milliseconds on the first zone. Using the dual zone system described above, the overall energy required to run the apparatus can be reduced.

Abstract: A method and apparatus for ventilating pocket spaces in a multi-cylinder dryer of a paper machine, in particular a high-speed paper machine whose running speed is higher than about 800 meters per minute, in the area of a so-called twin-wire draw. In the twin-wire draw, the drying cylinders in the drying group are arranged in two rows placed one above the other, in which rows the successive cylinders are placed in the upper row and in the lower row as interlocked. In each cylinder group, there are two drying wires, an upper wire and a lower wire for pressing the paper web against heated faces of the drying cylinder while being guided by guide rolls placed in gaps between the cylinders. The paper web runs as free draws between the rows of cylinders.

Abstract: A paper drying section utilizes two reversing rolls between each dryer roll to extend the available time for vapor to flash from the web. A vacuum box is disposed between the two reversing rolls to support and dry the felt and paper web as it passes from one reversing roll to another. An air cap is used to blow high velocity air onto the exposed surface of the paper web which is held by the vacuum box. The spacing of the two reversing rolls increases the wrap of the single tier dryer by approximately twenty percent over that of a conventional single tier dryer with a single reversing roll. Another configuration dryer section positions the first of the two reversing rolls downwardly beneath its adjacent dryer roll creating a long draw between the dryer roll and the first reversing roll. This long draw is supported by a vacuum box adjacent the felt.

Abstract: A method and device for drying a paper web wherein the paper web is supported on a drying wire without long open draws of the web. The paper web is contact-dried by pressing it with the drying wire onto a face of a contact-drying cylinder whose diameter is greater than about 1.5 m on a sector b whose magnitude is greater than about 180.degree.. The web is evaporation-dried as blowing-on drying and/or as through-drying by means of high-velocity drying-gas jets applied to the web on the drying wire on the face of the following large-diameter cylinder whose diameter is greater than about 2 m on a sector a having a magnitude greater than about 180.degree. while the web is on the side of the outside curve. The web to be dried is passed over a sector c of the suction roll which is subjected to negative pressure while the web is supported on the drying wire at the side of the outside curve. The magnitude of the sector of the suction roll has a magnitude greater than about 160.degree.

Abstract: A suction roll (1), in particular for a paper web dryer, comprising a perforated roll jacket (2), with at least one non-rotatable hollow shaft (3) which communicates with the interior of the suction roll via openings (7, 7') and at least one closing member (9) displaceable in the axial direction for separating off at least one peripheral region of the suction roll. The at least one, in particular disc-shaped dividing wall (5) is located in the suction roll interior and has at least one, preferably central opening (22). It can be of benefit when the dividing wall (5) corotates with the roll and/or when the at least one closing member (9) has the form of a hollow cylinder. Further, if the non-rotatable hollow shaft (3) is designed to be axially displaceable, it can be used to control the size of the opening (22) in the dividing wall (5).

Abstract: The present invention is a method and apparatus for eliminating the flutter of a paper web in the dryer section of a papermaking machine between two single felt configurations in which the web is transferred from a dryer fabric of a first configuration onto a dryer fabric of a second configuration along a common run of the fabrics, the transfer being effected from one fabric to the other by means of a vacuum transfer roll, with the second configuration dryer fabric being brought into contact with the web and around which the fabric is winding, whereby on the side of the first configuration dryer fabric upstream of a contact point between the web carried thereon and the second configuration dryer fabric winding around the vacuum transfer roll there is provided a vacuum zone defined by the first configuration dryer fabric for retaining the web in contact with the first configuration dryer fabric.

Abstract: A process for the guiding of fibre web or the like, in particular for paper production, especially in paper driers, wherein the suction applied can be varied both in real time operation and along the axes of the one or more suction rolls that is/are present and which may be used in conjunction with at least one travelling screen or the like. The object is to make the start-up process for the treatment of fibre webs on suction rolls more convenient without too much equipmental and operational overhead, and to prevent shrinkage of the web by providing good location at the web in the edge regions. This is achieved by restricting the suction which acts on the inside of the roll jacket to a region of the roll jacket which comes into contact with a lead-in strip for the fibre web during start-up operation. This process is continued until a sufficient length of fibre web has passed over the suction roll for the web to have reached its full or final width on this suction roll.

Abstract: The suction roll, especially for a paper web drier, comprises a perforated roll shell containing therein an internal chamber partitioned by a wall member transversely arranged with respect to the lengthwise axis of the suction roll. A connection flow communicates the interior of the suction roll with a suction device, preferably a vacuum pump. At least one blade or vane within the suction roll at least reduces or prevents a possibly arising rotational or cyclone-like flow. Thus, the pressure differential brought about by the suction device can be completely used for creating the suction action and for fixing the paper web at the suction roll. This rotational or cyclone-like flow particularly occurs when the suction action is applied through a hollow shaft or duct.

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.

Abstract: A dual air threading nozzle apparatus is disclosed for threading a paper web through a single tier drying section of a paper making machine. The single tier drying section includes a dryer roll, a dryer felt and a vacuum transfer roll. The dual air threading nozzle apparatus emits two angular planes of airflow for urging the paper web in a first direction to prevent engagement with the doctor blade for the dryer roll and in a second direction to closely conform to the dryer felt as it traverses between each dryer roll and vacuum transfer roll.

Abstract: A dryer section of a machine for manufacturing fiber webs, which includes a plurality of heatable drying cylinders arranged to form at least a first dryer group and a second dryer group, and arranged in horizontal cylinder rows, and including a plurality of suction rolls each being disposed between two adjacent cylinders. The cylinders of the first group have axes disposed in a first plane I, the suction rolls of the first group have axes disposed in a second plane II, the cylinders of the second group have axes disposed in a third plane III, and the suction rolls of the second group have axes disposed in a fourth plane IV. In accordance with different embodiments planes I and II may be coplanar, planes II and III may be coplanar; planes I and III may be disposed between planes II and IV; and the axes of the first drying cylinders and its associated suction roll of the second group may be disposed below the axes of the other drying cylinders and suction rolls of the second group.

Abstract: A dryer section of a machine for manufacturing fiber webs, which includes a plurality of heatable drying cylinders arranged to form at least a first dryer group and a second dryer group, and arranged in horizontal cylinder rows, and including a plurality of suction rolls each being disposed between two adjacent cylinders. The cylinders of the first group have axes disposed in a first plane I, the suction rolls of the first group have axes disposed in a second plane II, the cylinders of the second group have axes disposed in a third plane III, and the suction rolls of the second group have axes disposed in a fourth plane IV. In accordance with different embodiments planes I and II may be coplanar, planes II and III may be coplanar; planes I and III may be disposed between planes II and IV; and the axes of the first drying cylinders and its associated suction roll of the second group may be disposed below the axes of the other drying cylinders and suction rolls of the second group.

Abstract: A process is disclosed for the restrained drying of a paper web in a dryer section of a paper machine. The process includes the steps of wrapping the web with a felt during passage of the web with the felt around a dryer of the dryer section and thereafter wrapping the web around a portion of a guiding device disposed immediately downstream relative to the dryer so that edge curl of the web is minimized.

Abstract: A dryer apparatus is disclosed for drying a pressed web. The apparatus includes a plurality of single tier dryer sections in which successive sections dry alternate sides of the web, the web being transferred between successive sections without any open draw of the web such that the web is uniformly dried on both sides thereof while the web is restrained against cross-machine directional shrinkage. Each of the sections includes a single tier of dryers with an intermediate roll disposed between each adjacent dryer. A dryer felt extends in serpentine configuration around each dryer and roll such that the web is disposed between the felt and each dryer for drying one side of the web. The felt is also disposed between the roll and the web with the felt in direct contact with an alternate side of the web. The intermediate roll defines a plurality of circumferential grooves for diffusing boundary air following the felt that would otherwise tend to lift the web from the felt extending around the roll.

Abstract: In a screen drum device with a fan mounted endwise for generating suction through the screen drum surface, in front of a screen drum jacket, a baffle cover is usually provided. This baffle cover generates in a baffle chamber in front of the baffle cover, the accumulated pressure which is required for uniform processing of a web of material. In order to be able to handle optimally webs of different widths on the screen drum, the baffle cover in the vicinity of the narrow width of the goods is made so that it can be either removed completely or is given an opening mechanism, or the baffle cover has an additional screen cover located parallel thereto and displaceable with respect to the baffle cover.

Abstract: A dryer section with two dryer groups and a transfer for the paper web between the dryer groups. The receiving dryer group has a vacuum roll on which the felt of the proceeding dryer group is partially wrapped. An adjusting mechanism enables the wrap angle to be adjusted between an arc angle of 0 and 20 degrees.

Abstract: A dryer section of a paper making machine is divided into several dryer groups, each comprising a plurality of dryer cylinders, a plurality of reversing rolls between neighboring cylinders and a respective web supporting belt wrapping around the cylinders of a dryer group. Within each dryer group, the web travels, in continuous contact with the supporting belt, alternately over the dryer cylinders and the reversing rolls so that the web comes into direct contact with the cylinders and the supporting belt comes into direct contact with the reversing rolls. The cylinders are arranged in several rows which are inclined to the vertical, alternately rearwardly and forwardly defining V-shaped double rows. The end of each row and the starting point of the following row are formed by two cylinders arranged horizontally alongside of each other. The rows of dryer cylinders succeed each other in the manner of a zig-zag line. Each inclined row comprises about three cylinders.

Abstract: An on-line drying and heat treating process with drying from internally heated fiber carrying rolls and heat treating from turbulent hot gas jets directed onto the fiber carrying rolls.

Abstract: A method in a drying group or groups provided with a single-wire draw in a multi-cylinder dryer of a paper machine in the draw of a web. The multi-cylinder dryer comprises drying cylinders heated by means of steam or equivalent, with the web being pressed by a drying wire against the cylinder faces of these drying cylinders. The multi-cylinder dryer has leading or lower cylinders on which the web runs outside the drying wire which is, for example, a felt. The leading cylinders or rolls are provided with holes passing through a mantle of the leading cylinders or rolls, these holes being fitted to open into an inner space of negative pressure within the leading cylinder or roll and to open, at an opposite end, into grooves provided on a mantle face of the rolls. The negative pressure inside the roll is arranged to be transmitted to the grooves provided on the outer face of the roll mantle, so that an adhesion force is applied to the web through the grooves.