Abstract: To automate alarm management in modular production installations, provided is, with respect to a modular production installation, for which, for its modular, manufacturer-independent construction and operation, “process equipment assembly” modules, controlled by a programmable PEA controller and simulated by means of a configurable PEA simulation, are integrated into the production installation, by means of a “module type package <MTP>” mechanism for the PEA module description, in the course of a process orchestration which is standardized the following is carried out in the alarm management: —all states of the modular production installation with respect to triggered faults of possible fault cases of the production installation are virtually run through and simulated; —simulation faults that occur are logged concomitantly by means of alarms, which provide identification and an alarm message log is created and/or alarm chains are identified and alarm relationships in the alarm chains are determined.

Abstract: A transporting device includes a first driving roller which transports the base material; a second driving roller which is disposed to be closer to a downstream side of the transporting direction than the first driving roller, and transports the base material; a driven roller which nips the base material between the second driving roller and the driven roller, and rotates together with the second driving roller; and an inter-roller transporting path which is provided between the first driving roller and the second driving roller, and through which the base material is transported in a state where the base material is suspended in a direction of gravity and bent. The second driving roller starts winding the base material at a position which is closer to an upstream side of the transporting direction than a position where the driven roller is in contact with the base material.

Abstract: A system and a method for ventilating an offset pocket space located in a drying section of a papermaking machine, the offset pocket space being situated between three axially parallel drying cylinders over which a paper web consecutively runs, a first and a third of the drying cylinders being vertically spaced from a second of the drying cylinders, the method comprising creating a positive pressure zone between the body and the felt between the third cleft and the second cleft.

Abstract: A machine for the production of a fibrous web. The fibrous web being a paper web, a cardboard web or a tissue web. The machine including a hot air hood, an upstream drying zone, a downstream dryer cylinder and a dryer hood. The upstream drying zone has an area in which the moving fibrous web is treated with hot air from the hot air hood, the hot air hood being allocated to the upstream drying zone. The downstream dryer cylinder is a Yankee-Cylinder. The dryer hood is associated with the downstream dryer cylinder for further drying of the fibrous web. The hot air for the hot air hood is at least partially recovered from the dryer hood which is associated to the downstream drying cylinder.

Abstract: A flat surface dryer (1) includes a sealed targeting box (2) with its replacement and exhaust air ports (12, 31; 20), and an air fan (3), the flat surface dryer (1) being an air circulating flat surface dryer, including an element (19, 21, 28, 30) for regulating the amounts of replacement air and exhaust air with respect to the total amount of air circulated by the air fan (3). Also described is a method for drying a flat surface (6) with the flat surface dryer (1).

Abstract: A paper or board machine having a machine dryer section with a drying group with single-wire draw. A drying wire (F) presses the web (W) on a drying cylinder (10) against heated cylinder surfaces, and the web (W) remains at the side of the outside curve of reversing cylinders (11) situated between drying cylinders (10). For enhancing runnability of the web (W), a runnability component (20) is in a pocket space (T) confined by two adjacent drying cylinders (10) and a reversing cylinder (11) situated between them and by the drying wire (F). The web (W) passes from the drying cylinder (10) to the reversing cylinder (11) as a short transfer of 80-400 mm, where a negative pressure effect produced by the runnability component (20) is applied and confined by seals of the runnability component (20) against the surfaces of the drying cylinder (10) and reversing cylinder (11).

Abstract: The steel-made Yankee cylinder includes a cylindrical shell (11) joined to two ends (13, 15), to which are fixed respective-support journals (3). The cylindrical shell (11) is joined to the ends through a circumferential weld formed between opposing surfaces of each end and of the cylindrical shell.

Abstract: The object of the invention is an apparatus and a method for improving the detachment of paper (1) from the cylinder of a paper machine in a drying section implemented with a single wire transfer, which drying section comprises means for heating the paper on the drying cylinder (3) and for transporting it onwards on the wire (2) via a hitch roll (8) to the next drying cylinder such that the paper together with the wire in the section between the cylinders is sucked against the wire by means of low pressure. What is essential to the invention is that in order to improve the detachment of the paper (1) an apparatus is installed on the opposite side of the drying wire (2) at the detachment point (7), which apparatus comprises a nozzle (14), with which an air jet (11) is blown against the direction of travel (15) of the drying wire, and a carrying surface (9) such that the air jet (11) ejects secondary air (17) along with it causing an air flow (18) between the planar carrying surface (9) and the drying wire (2).

Abstract: Described are an apparatus and a method for cooling a web. The apparatus includes an inner cylinder having a void therein and configured for coupling to a gas source. The apparatus also includes an outer cylinder having an inner surface, an outer surface to support a web and apertures between the inner and outer surfaces. The outer cylinder rotates about the inner cylinder so that gas provided to the void of the inner cylinder flows through the apertures that are adjacent to the void and passes to the outer surface of the outer cylinder to increase the heat transfer between the web and the outer cylinder. The volume of gas introduced into the vacuum deposition chamber during a process run is thereby limited. Advantageously, the apparatus enables higher deposition rates and increased productivity.

Abstract: In a method for detaching a web threading tail from a moving surface in a fiber web machine, the web threading tail (12) is detached from a moving surface (23) by means of air that flows from a blow-off blow channel (19) included in a blade holder (14). A trailing blow (26) is directed to the web threading tail (12) using air that flows from a trailing blow channel (17) included in the blade holder (14). The blade holder (14) includes a flow surface (32), and the trailing blow (26) is blown to the same direction with or in a small angle relative to the flow surface (32). The invention also relates to a corresponding blade holder and a doctor apparatus for detaching a web threading tail from a moving surface in a fiber web machine.

Abstract: A through-air dryer system that diverts the airflow within the through-air dryer during warm up and cool down from the normal airflow during the drying of paper in the papermaking process. During warm up and cool down, a majority of the airflow is supplied to one of the dryer's heads and extracted through the opposite head to reduce thermal stresses. If needed to further reduce thermal stresses, a minority of the airflow is supplied through the dryer's shell.

Abstract: A dryer uses conduits to carry a heating medium, such as steam, to heat the outer surface of the dryer. The volume of steam is successfully reduced to non-explosive levels and the shell need not be designed to prevent an explosion. Conduits may be formed through the shell itself or grooves may be formed on the inner surface of the shell, with the conduits retained within the grooves. Also, the conduits can be placed against the inside surface of the dryer and a material, such as zinc, can be filled in about the conduits. The material serves to both retain the conduits in place and thermally couple the conduits to the dryer to assure efficient heat transfer between the conduits and dryer. These modifications relieve the dryer from the Unfired Pressure Vessel classification to the classification of a piping assembly under ASA code regulations. This results in savings in operation safety, installation cost and operating costs due to the absence of costly inspections.

Abstract: The invention relates to an arrangement and a method for sealing of a pocket space between drying cylinders (2, 3) in a paper machine or similar. In the method for sealing of the pocket space: a wire (5) is moved supported by the first and the second cylinder (2, 3, 4), a gap between the pocket space (15) and the space outside (24) it is sealed by a runnability component (6), which comprises at least a sealing surface (19, 22) and a blow nozzle (21) provided with a nozzle slot (26) of a size of 0.5-3.5 mm and elongated in the cross direction, the sealing surface (19, 22) is kept at a distance of 5-15 mm from the moving wire (5), air is blown with the blow nozzle (21) from a blow point (27) and along the sealing surface (22) towards a sealing point (16) and further via the sealing point (16) away (24) from the pocket space. The invention comprises also a runnability component (6) and a method for manufacturing the same.

Abstract: An apparatus for handling a moving material web includes: a treatment unit including a rotating conveyor belt which forms a closed loop and carries the material web; a second treatment unit with a second conveyor belt which also forms a closed loop, both treatment units being connected parallel relative to each other; a first switch-over for the transfer of the web from the first to the second conveyor belt; and a second switch-over unit for the transfer of the web from the second to the first conveyor belt.

Abstract: A shoe device secured to a syphon is disclosed for removing condensate from an internal surface of a rotating cylinder. The shoe device includes a shoe portion which is disposed adjacent to the internal surface of the rotating cylinder. The shoe portion defines a passageway having an upstream and a downstream end. The passageway permits a flow there through of the condensate from the internal surface of the rotating cylinder, through the upstream end of the passageway to the downstream end of the passageway. The shoe portion has a first and a second side, a surface extending between the first and second sides of the shoe portion. The surface is disposed adjacent to the internal surface of the cylinder. The shoe portion also has a leading and a trailing end and a face extending between the leading and trailing ends of the shoe portion. A clamp is secured to a distal end of the syphon and is connected to the shoe portion for clamping the shoe portion to the syphon.

Abstract: Web stabilizer particularly for one-sided flotation of a running web. The device includes two discharge slots which allow for increased draw down force, which flattens machine direction wrinkles in a floating web. There is a primary discharge slot and a second discharge slot spaced from and stepped down from the primary discharge slot, a first web support surface between the primary discharge slot and the secondary discharge slot, and a second web support surface downstream of the secondary discharge slot in the direction of web travel. An integral blower provides a supply of air that is uniformly distributed to the primary and secondary slots. Air discharged from the primary slot is gathered into the air stream of the secondary slot and creates an increased air cushion to provide greater support to the web and thereby remove machine direction web wrinkles caused by higher tension in light weight webs.

Abstract: A fiber-web machine dryer section has a drying group with single-wire draw so the drying wire (F) presses the web (W) against heated cylinder surfaces with the web (W) at the side of the outside curve of reversing cylinders (11) situated between drying cylinders (10, 12). A pocket space (T) is formed between two adjacent drying cylinders (10) and a reversing cylinder (11) situated between them, and the drying wire (F). A negative pressure component (20) placed in the pocket space (T) creates a pressure difference over the drying wire (F) and the web (W) for attaching the web (W) to the drying wire (F) so the cross-direction shrinkage of the web (W) is controllable. The wire tension (F) is maintained at a level help control cross-direction shrinkage of the web. The pocket space (T) is sealed by sealing members (25, 26) to maintain negative pressure in the pocket space.

Abstract: In a method for detaching a web threading tail from a moving surface in a fiber web machine, the web threading tail (12) is detached from a moving surface (23) by means of air that flows from a blow-off blow channel (19) included in a blade holder (14). A trailing blow (26) is directed to the web threading tail (12) using air that flows from a trailing blow channel (17) included in the blade holder (14). The blade holder (14) includes a flow surface (32), and the trailing blow (26) is blown to the same direction with or in a small angle relative to the flow surface (32). The invention also relates to a corresponding blade holder and a doctor apparatus for detaching a web threading tail from a moving surface in a fiber web machine.

Abstract: A hood (10) is located above a web forming section (12), a press section (14) and/or a dryer section and includes a ceiling (30), a back side wall, and a front side wall (44), which includes staggered wall segments (42). The wall segments (42) are adapted to move along rails or similar. The front side wall segments (42) are adapted to form two or more groups (46). A cleaning station (40) is arranged to automatically clean the side wall segments (42) as they move past the cleaning station.

Abstract: A system and method for transferring a continuously advancing paper web from a dryer to a reel section is provided. The system includes a first fabric defining a first moving conveyor. The first fabric may be a permeable fabric, which is positioned downstream from the dryer. A second fabric, which may also be permeable and defines a second moving conveyor, is also included. The first moving conveyor overlaps the second moving conveyor for a predetermined distance, and the first and second moving conveyors are configured to receive the paper web between the conveyors. A vacuum device is rotatably disposed against the first moving conveyor, and the dryer and the vacuum device are disposed relative to each other to form an open draw. The vacuum device is configured to produce a vacuum to attract the web to the first fabric for transferring the advancing web into the predetermined distance where the first and second conveyors overlap.

Abstract: The invention relates to a drying cylinder which is used to dry a paper, cardboard, tissue or other web of fibrous material in a machine for the production and/or for the transformation thereof. The drying cylinder includes a support body and an external cover layer which is heated by a hot fluid. The thermal flow passing through the external cover layer is increased such that at least one cavity is provided between the support body and the external cover layer through which the fluid flows. The external cover layer is predominately so thin that the ratio formed by the thermal conductivity of the material and the thickness of the external cover layer is greater than a threshold value of 3.2 kW/m2K for steel, 30 kW/m2K for aluminum, 18 kW/m2K for bronze alloys, 3.4 kW/m2K for copper and 6.1 kW/m2K for magnesium.

Abstract: A wet end of a paper or board machine has at least one vertical, self-supporting installation module (10a, 10b) to be positioned into connection with the machine which module is supported from its lower end by foundation structures of the machine construction and which extends at least to the height of a second maintenance platform (50b) of the machine, which installation module (10) includes at least valves (40) and pipes (30) related to the hydraulic and/or pneumatic actuators of the machine.

Abstract: A paper machine configured as a swing machine capable of producing both light and heavy grades providing a Yankee hood split into a wet end half and a dry end half, at least one hood half being a flex-hood half wherein the supply for that half is capable of being run with either combustion heat or recycled heat and is capable of either recirculating the exhaust from the hood or discharging it to the atmosphere. The heater for the flex-hood half comprises both a primary combustion heat source and an indirect heat source capable of extracting by-product heat from another operation. The exhaust system for the flex hood half is capable of being run in either a straight through mode or in a recirculating mode.

Abstract: A vacuum belt conveyor of a web forming machine for transferring a threading tail has at least two turning rolls (16, 17) and an air-permeable belt loop (20), arranged around the turning rolls (16, 17). The vacuum belt conveyor also has vacuum means (22) for creating a vacuum effect on both the section of the belt loop (20) conveying the threading tail (23) and in connection with the first turning roll (16) of the turning rolls (16, 17). Arranged in connection with the first turning roll (16) in the travel direction of the threading tail (23) there is at least one cross-directional dividing structure (24) for creating at least two axial vacuum zones (25).

Abstract: A steam box for applying steam to a moving web comprising a housing having a leading end and a trailing end positionable above and proximate to a moving web; a supply header within the housing, said supply header in communication with a steam source; at least first and second steam chambers aligned with said leading edge in the direction of movement of said web, said first and second steam chambers able to receive steam from the said supply header to apply steam through respective first and second steam discharge points to the moving web, and a screen plate securable to said housing, said screen plate including a horizontal plate; and a first descending barrier positioned between said first and second steam discharge points, said descending barrier having a first trailing side adjacent to said-second steam discharge point to protect said second steam discharge point from stock flung from the web.

Abstract: A dryer uses conduits to carry a heating medium, such as steam, to heat the outer surface of the dryer. The volume of steam is successfully reduced to non-explosive levels and the shell need not be designed to prevent an explosion. Conduits may be formed through the shell itself or grooves may be formed on the inner surface of the shell, with the conduits retained within the grooves. Also, the conduits can be placed against the inside surface of the dryer and a material, such as zinc, can be filled in about the conduits. The material serves to both retain the conduits in place and thermally couple the conduits to the dryer to assure efficient heat transfer between the conduits and dryer. These modifications relieve the dryer from the Unfired Pressure Vessel classification to the classification of a piping assembly under ASA code regulations. This results in savings in operation safety, installation cost and operating costs due to the absence of costly inspections.

Abstract: The invention relates to a method and an apparatus for drying a moving web of material at a paper or board machine. The drying is performed by a heated drying cylinder (1) transverse to the direction of travel of the web, past which the web is being led. According to the invention, the drying cylinder (1) has been constructed so that its temperature can be adjusted independently at different locations in the longitudinal direction of the cylinder, i.e. the transverse direction of the web. With the adjustability of the drying cylinder it is possible to eliminate moisture differences occurring in the transverse direction of the web in connection with the drying. Especially, it is possible to eliminate moisture lines in the longitudinal direction of the web, which are generated when forming the web on the wire.

Abstract: A fiber-web machine dryer section has a drying group with single-wire draw so the drying wire (F) presses the web (W) against heated cylinder surfaces with the web (W) at the side of the outside curve of reversing cylinders (11) situated between drying cylinders (10, 12). A pocket space (T) is formed between two adjacent drying cylinders (10) and a reversing cylinder (11) situated between them, and the drying wire (F). A negative pressure component (20) placed in the pocket space (T) creates a pressure difference over the drying wire (F) and the web (W) for attaching the web (W) to the drying wire (F) so the cross-direction shrinkage of the web (W) is controllable. The wire tension (F) is maintained at a level help control cross-direction shrinkage of the web. The pocket space (T) is sealed by sealing members (25, 26) to maintain negative pressure in the pocket space.

Abstract: The object of the invention is an arrangement for stabilizing a paper web (3) in a paper machine, which arrangement comprises at least three cylinders (4, 5, 6) which have been arranged so that a pocket space is formed between them, a blow box (7) arranged in the pocket space, which blow box has a blow nozzle (12), in which a nozzle slot (19) has been arranged, a separate wall (10), substantially in the direction of the blow box (7), which wall has a first edge and a second edge that are substantially parallel, which has been attached from its first edge to the blow box (7), whose height in the travelling direction of the paper web (3) is 25-300% of the height of the blow box (7) in the travelling direction of the paper web (3), in the second edge of which wall there has been arranged a boundary layer air doctor (15), which extends substantially unto the surface of the cylinder (4, 5, 6), and which wall (10) has been attached to the blow box (7) so that the blow box (7) and the wall (10) form a space in the a

Abstract: Equipment for leading a web threading tail in a paper machine has at least two sequential surfaces (11) in the direction of travel of the web threading tail (10), between which a nozzle (12) is arranged to form a directed air blast and thus to transport the web threading tail (10). The equipment has an element (13) in which an exhaust zone (20) is arranged in the surface (11) before the nozzle (12) in the direction of travel of the web threading tail (10), for leading air away from the element (13) between the web threading tail (10) and the surface (11).

Abstract: The invention relates to a guiding device for a continuous paper sheet comprising at least one guiding element which is disposed downstream with respect to an application group and used in the form of an air circulating channel in order to ensure a contactless guiding in a machine producing and/or processing a continuous material sheet, in particular a paper or paperboard sheet. Said guiding element consists of a guiding surface made at least partially of an air-permeable porous material which is exposed to a compressed air pressure in such a way that air can circulate therethrough, thereby forming an air cushion between said guiding surface and a moving material sheet.

Abstract: A system and method for transferring a continuously advancing paper web from a dryer to a reel section is provided. The system includes a first fabric defining a first moving conveyor. The first fabric may be a permeable fabric, which is positioned downstream from the dryer. A second fabric, which may also be permeable and defines a second moving conveyor, is also included. The first moving conveyor overlaps the second moving conveyor for a predetermined distance, and the first and second moving conveyors are configured to receive the paper web between the conveyors. A vacuum device is rotatably disposed against the first moving conveyor, and the dryer and the vacuum device are disposed relative to each other to form an open draw. The vacuum device is configured to produce a vacuum to attract the web to the first fabric for transferring the advancing web into the predetermined distance where the first and second conveyors overlap.

Abstract: An apparatus for dewatering a fiber web in a paper machine includes a heated drying surface, a permeable fabric carrying the fiber web, and a condensing region adjacent a portion of the permeable fabric on a side opposite the fiber web. The fiber web is interposed between and contacts each of the heated drying surface and the permeable fabric. The condensation region has: a) a temperature which is less than a temperature of the permeable fabric; and/or b) a pressure which is greater than an ambient pressure.

Abstract: A transport belt, in particular for machines for the production of web material such as paper or paperboard, the transport belt including a web material contact side having surface depressions, such that the surface depressions are filled with filler material to provide a substantially flat web material contact surface.

Abstract: Machine for producing a fibrous material web and process for guiding the web through the machine. The machine includes a wire section, a drying section, arranged downstream of the wire section with regard to a web travel direction, having at least one free web draw, a first and second shoe press separated in the web travel direction, and an upper felt and a lower transfer belt arranged to guide the fibrous material web through the second shoe press. The lower transfer belt is structured and arranged to transfer the fibrous material web to the drying section, and the material web is guided in a closed draw from the wire section to a first free web draw, with regard to the web travel direction, in the drying section. At least one high-performance drying device is positioned before the first free web draw.

Abstract: A paper or board mill includes a drying section, which includes at least one drying cylinder group and at least one impingement drying unit (PK). The method uses a turbine engine (10), the combustion gases (1) of which are conducted at least into the impingement drying unit (PK) as impingement air.

Abstract: A system for maintaining calender rolls of a paper machine clean when producing high-gloss paper or coated paper, such as LWC or MWC. To prevent a coating agent, such as coating dye, from adhering onto and soiling a smooth surface of a calender roll, with an overheating phenomenon, the system has a second measurement station (10) provided with measuring and indicator means for producing an output indicating soiledness of the web (W) or a humidity profile. When the output of the second measurement station (10) indicates excessive soiledness or an uneven humidity profile, the system performs at least one of: cleaning the surface of the smooth-surfaced calender roll; changing the nip load in the calender (5); making a correction adjustment of the CD-directional humidity profile of the web (W); cutting the web (W) and conducting it into the pulper; and/or changing the running speed of the web (W).

Abstract: The invention relates to an arrangement for threading a pulp web (W) from the press section (1) of a pulp machine to the dryer (2) of the pulp machine. The arrangement comprises a closing tail threading belt (3) or the like, which is arranged to convey the narrow tail end (Wh) formed on the pulp web (W) inside the dryer (2), where the tail threading cord travels outside the edge of the normal web line of the pulp web. The tail end (Wh) can subsequently be broadened into a normal-width pulp web (W). The arrangement further comprises means (7) for gripping the tail end (Wh) in order to bring the tail end inside/between a closing tail threading cord (3) or the like, whereby the gripping means (7) are arranged to function at the normal running speed of the pulp machine.

Abstract: A drying section of a machine for the manufacture of a material web, in particular of a paper or of a board web, comprises a smoothing nip which is extended in the web running direction and is formed between two pressing areas lying opposite one another of which at least one is formed by a shoe roll, with at least 70%, and preferably at least 90%, of the outer shoe roll diameter lying above the machine base.

Abstract: The invention relates to an air impingement system arranged outside the jacket of an air impingement roll in the drying section of a paper machine or the like for heating and drying a web travelling around the said air impingement roll. The air impingement system comprises a mainly closed hood, which has control means for directing air onto the paper web. From the hood, air is directed by blowing with at least one fan to the blower nozzles and back again into the said hood as a circulation air process, and the system incorporates at least one heating device for heating the air. The air impingement system's hood and its said equipment are used in conjunction with an air impingement roll, which is of the size of approximately 1.5–2 m in diameter. The hood of the air impingement roll is at maximum 5 m high, preferably only 1.5–2.5 m high.

Abstract: A method and an apparatus for the production and processing of a material web, specifically a paper or cardboard web are described, whereby the material web is first wound and subsequently unwound for a subsequent finishing process and whereby the material web after being wound and prior to the finishing process is remoistened so that its moisture immediately prior to the finishing process is higher than that immediately prior to winding.

Abstract: An apparatus for a dryer section of a paper or board machine has a drying group (R) and an impingement drying unit (10) which is placed above and/or below a row (DSR) of drying cylinders (3). A drying fabric (1) supported paper or board web (2) is conducted past the impingement drying unit (10) having at least one impingement surface (IP1, IP2) the side profile of which is straight, changeably curved in its radius of curvature, in the shape of a broken line or a selectable combination of these, and that the impingement surface or a tangent line to the impingement surface or a line passing via the beginning and the end of the impingement surface or an extension of the line forms on the impingement side an angle with a horizontal plane parallel to the machine level, which angle is ?120°, advantageously 120°–60°, most advantageously about 90°.

Abstract: A system and method for transferring a continuously advancing paper web from a dryer to a reel section is provided. The system includes a first fabric defining a first moving conveyor. The first fabric may be a permeable fabric, which is positioned downstream from the dryer. A second fabric, which may also be permeable and defines a second moving conveyor, is also included. The first moving conveyor overlaps the second moving conveyor for a predetermined distance, and the first and second moving conveyors are configured to receive the paper web between the conveyors. A vacuum device is rotatably disposed against the first moving conveyor, and the dryer and the vacuum device are disposed relative to each other to form an open draw. The vacuum device is configured to produce a vacuum to attract the web to the first fabric for transferring the advancing web into the predetermined distance where the first and second conveyors overlap.

Abstract: The invention relates to a method for conveying and guiding a lead-in strip in a paper machine, in which method a lead-in strip is directed over a run of a conveyor in the paper machine and a longitudinal vacuum effect is produced across the run of the conveyor in the direction of moment of the run of the conveyor.

Abstract: A method and equipment for tail threading in a paper machine in which tail threading is carried out in stages: the web is guided to the broke treatment at a selected dryer, a cut is formed in the web to separate a narrow tail from the rest of the web, i.e. the broke web, prior to the dryer, the edge opposite to the cut of the broke web is turned away from the cutting point to form an open draw between the tail and the broke web, the tail is guided from the selected dryer to the following section while the broke web is transferred further to the broke treatment, while travelling in a controlled manner, the tail is widened to the full width and the broke web is simultaneously reduced away.

Abstract: A method and an apparatus for web threading in a drying section of a paper machine or the like. A leader (24) and a so called run-down strip are formed by cutting in the web coming to the drying cylinder in the drying section. An underpressure box (18) is arranged at the opening gap between the drying cylinder (14) and the drying wire, on that side of the wire which is away from the web, whereby this box can direct against the web an underpressure which is controllable in the machine's cross direction. The underpressure box creates an underpressure region (34?) between the leader and the underpressure box, the region having an underpressure p1 at the detachment point, i.e. in the area where the wire is detached from said drying cylinder (14), which underpressure is sufficient to detach the leader from said drying cylinder.

Abstract: Process and apparatus for drying a material web. The process includes guiding the material web to at least one heated area having a jacket surface of a cylinder having a diameter of between about 4-10 meters, setting the material web, having a dry content of between about 45-55%, onto the at least one heated area, maintaining the material web in uninterrupted contact with the at least one heated area at least until the material web achieves a firmness sufficient for detaching the material web from the heated area, and detaching the material web from the at least one heated area with a dry content of between about 55%-65%.

Abstract: A web (16) running from an opening nip (K1) between a cylinder (10) and a supporting fabric (18) toward a roll (14), is supported by a negative pressure created by a blow box (30). In an intensified negative pressure region (34?), i.e. close to the disengaging point (40) between the supporting fabric and the cylinder, the pressure is greater than at a distance from this disengaging point. The negative pressure is controlled according to parameters which act on the runability of the web and which can be varied, such as web velocity, web solid contents, pulp composition, paper or paper board quality, web grammage, a characteristic of the web, such as porosity, traction acting in the web, or web tension, cylinder temperature, and/or the running situation, such as a web break, a threading situation, or a normal run, so the desired runability is maintained between the cylinder and the roll.

Abstract: A through-air drying apparatus is disclosed. The through-air drying apparatus includes a rotating drying cylinder over which a tissue web is carried and dried. A hood surrounds the drying cylinder leaving an open free end. In accordance with the present invention, an external baffle is positioned adjacent to the open free end of the drying cylinder to prevent external air from leaking in or infiltrating the drying cylinder.

Abstract: A Yankee cylinder or the like at the dry end of a paper machine has at least a drying cylinder, a hood covering the drying cylinder, a web guiding means, and a roller. After the drying cylinder at the dry end of the machine, seen in the machine direction, a covered area which above and on the sides is at least mainly covered extends at least to the area of the roller.