EP2783039B1 - Method for transferring a material web from a drying arrangement to a downstream functional unit, and drying device - Google Patents

Description

The invention relates to a method for transferring a material web, in particular a fibrous web in the form of a paper, board or tissue web of a dry assembly of a machine for producing such a material web, in which the material web supported on an endlessly circulating dry belt alternating over a plurality of heated drying cylinders under direct contact with their surface and arranged therebetween deflecting rollers, to a downstream of the drying assembly functional unit at startup or after a disturbance by transferring a Aufführstreifens, in which in a process stage, at least a partial strip of the web from the dry assembly or the web web width in a arranged below the drying arrangement collecting device is performed.

The invention further relates to a drying device of a machine for producing a material web.

To reduce curl, in dry devices, series connections of single-row dry arrangements are used for drying respectively different web sides. In this case, the material web comes within a drying arrangement with only one side with the surface of the heated drying cylinder in direct contact. An embodiment of a drying apparatus in which in the last drying arrangement the upper material web and in all preceding dry arrangements the underside of the material web comes into contact with the heated drying cylinders and the drying cylinder row of the last drying arrangement runs downwards in the web running direction is known from the document DE 10 2008 000 133 A1 previously known. At the end of the last drying arrangement, a transfer device for transferring the fibrous web into the next machine section or the next functional unit is provided, so that in a demolition of the fibrous web can be listed quickly and thus with minimal loss of production at unchanged operating speed again. The transfer takes place by removing the material web or a Aufführstreifens on the dry belt. The residual web is guided into a collecting device in the form of a pulper. Furthermore, it is known, in case of malfunctions of the operation, to drive the web web-width into a collecting device in the form of a pulper.

DE 10 2008 000133 A1 such as DE 10 2009 027608 A1 describe a method and a drying device comprising the features of the preamble of independent claims 1 and 8.

The invention had the object of further improving a method for guiding a material web or a partial strip of these in a collecting device, in particular to ensure even safer and more stable. The solution according to the invention should be suitable for embodiments of dry arrangements in which due to the arrangement of the drying cylinder, a decrease of the drying cylinder itself is not possible or only against the direction of gravity.

The solution according to the invention is characterized by the features of claims 1 and 8. Advantageous embodiments are described in the dependent claims, which can be used individually or in combination with each other with the features of the independent claims in an advantageous manner.

The invention relates to a method for transferring a material web, in particular a fibrous web in the form of a paper, board or tissue web of a dry assembly of a machine for producing a such material web, in which the material web supported on an endlessly circulating dry belt alternating over a plurality of heatable

Drying cylinders under direct contact with their surface and in between arranged deflection rollers is guided to a downstream of the drying assembly functional unit at startup or after a disturbance by transferring a Aufführstreifens, in which in a process stage, at least a partial strip of the material web from the drying assembly or the web web width is guided in a arranged below the drying arrangement catcher, wherein the material web or the partial strip of the material web is guided on the dry belt in the, in particular in the vertical direction offset catcher supported on the in the direction of passage of the web through the drying arrangement last drying cylinder of the drying arrangement.

A partial strip is understood to be a strip of a material web whose extent in the width direction is characterized by a width in the longitudinal direction and whose extent in the width direction is smaller than the width of a completely wide-traveled material web. The partial strip can be present as a leader strip or residual web.

A leader strip serves to transfer the material web between successively arranged functional units. The extension in the width direction is characterized by a substantially smaller width than in the longitudinal direction. The width of the Aufführstreifens can vary in the longitudinal direction, in particular be characterized by a steady change or kept constant over a predefined length range. Such Aufführstreifen are usually formed by so-called edge strips, which are generated in the lateral end portions of the web by cutting them with further formation of a residual web.

A residual web is understood to mean that part of the material web which, after being severed, in particular separation of the leader strip from the material web, remains.

Widening the web to the desired width means changing the width of the leader in the cross-machine direction while reducing the width of the remainder web by changing the position of a separator for separating the web into the leader and a remnant strip.

The term dry belt comprises at least one endless, i. As a loop present band in a variety of designs, which is guided over guide rollers and driven by at least one drivable roller. By the drive this runs around. The dry belt is preferably a dryer fabric. The direction of rotation of the drying belt coincides in the support region for the material web with the direction of passage of the material web through the drying arrangement.

Subordinate functional units are assemblies, assemblies, devices and / or facilities that serve the further guidance and / or treatment of the material web or web components. Depending on the arrangement of the drying arrangement, it may, for example, be one of the following functional units: a further drying arrangement, a reeling device for the material web, a smoothing device or a downstream application device.

A collecting device is understood to mean a device which serves for receiving and / or storing and / or at least partially processing at least parts of the material web.

The solution of the invention allows the support on the dry belt, the safe transfer of a partial strip of a web or the web with full width in a vertical direction to the dry assembly, especially a portion of this offset catcher in transfer situations, in which the web on the drying cylinder or not in the direction of gravity to lose weight. The inventive Solution is thus particularly suitable for guiding partial strips or the entire material web of single-row drying arrangements whose drying cylinders are arranged one above the other in a vertical position with respect to their longitudinal axes in an aligned position or offset from one another such that a theoretical connecting line through their longitudinal axes in the vertical direction or inclined with respect to a vertical plane. The angle of inclination may be in the range of 70 ° to 110 °.

Furthermore, the solution according to the invention is also suitable for guiding partial strips or the entire material web from inverted single-row drying arrangements, i. arranged in series drying cylinders arranged therebetween deflecting rollers whose longitudinal axes are arranged in the vertical direction above the longitudinal axes of the drying cylinders.

According to the invention, the material web or the partial strip of the material web after the passage in the last drying cylinder on the drying belt via a, formed by a portion of the circulation path of the drying belt holding area to a characterized by the detachment of the web or the partial strip from the dry belt release area with this guided, over at least a portion of the holding area the web or the sub-strip is held by vacuum on the drying belt. As a result, the partial strip or the entire material web can be transferred after a demolition in a firmly defined position relative to the drying belt in the collecting device.

According to the invention, the guidance of the material web or of the partial strip takes place within the holding region with the drying belt via a suctionable downstream of the last drying cylinder. After the foamable roller, the material web or the partial strip is released from the drying belt and drawn into the collecting device. The suctionable roll is used to optimize by their position relative to the drying cylinder descriptive course of the holding area and for guiding the material web in the direction of collecting device arranged such that it is wrapped in installation position at least over a portion of the outer periphery above a characterized by the longitudinal axis of the besaugbaren roller and a perpendicular to this in a horizontal plane level of the dry belt. The main advantages of the suctionable roller are the possibility of a controlled web run in the pulper, the guarantee of a defined picking position during transfer and a considerably improved reject discharge during a demolition.

According to a particularly advantageous development, the material web or the partial strip of the material web is held on the drying belt by applying negative pressure to the drying belt in the region of the holding region between a discharge line of the drying belt from the last drying cylinder and the suctionable roller. This measure allows safe guidance in a fixed position relative to the drying belt to the release area.

For targeted recording of the material web or the partial strip of the material web in the collecting device, this is fed after release from the drying belt in the collecting device, for example by means of both sides of the web or strip arranged Pulperspritzrohren or sucked. This solution is particularly suitable when using collecting devices with small inlet openings, collecting devices, for which only a small amount of space is available in order nevertheless to ensure fast and safe transfer into them.

The guide according to the invention of the material web or a partial strip of the material web into a collecting device forms an essential part of a transfer process. For this purpose, within or before the drying arrangement or in the direction of flow after the discharge line of the drying belt from the last drying cylinder of the drying arrangement, a leader strip by separation of the Material web generated from this. The discharge line of the drying belt and when guiding web material components, in particular the Aufführstreifens or the entire web at this last drying cylinder describes the local course of detachment of the dry belt or web components from the outer circumference of the drying cylinder in the cross-machine direction and is in idealized form by a parallel to the longitudinal axis of Drying cylinder characterizable.

The Aufführstreifen is performed in a first embodiment as a partial strip of the material web in the collecting device and subsequently driven to full width in the collecting device. In a second embodiment, the leader strip, after the last drying cylinder of the drying assembly, is guided by the drying belt into the looping area of the drying belt with the sweeping roll downstream of the last drying cylinder, removed from the drying belt in a take-off area within the wrap area and transferred to the downstream functional unit. The acceptance region describes an area at which the material web, in particular the leader strip, is removed from the drying belt. In an idealized form, this can be described by a take-off line. As a result of the arrangement of the suctionable roll, the removal region is located in the first or fourth quadrant with respect to a coordinate system laid in the first or fourth quadrant through the longitudinal axis of the suctionable roll and is thus easily accessible. The arrangement of the removal area in the upper half of the suctionable roller allows the targeted removal of a Aufführstreifens and from this position safe transfer of this in a downstream functional unit also for arrangements of the drying cylinder, in which no decrease of these is possible. The suction is carried out at least in the region of the removal region, preferably in the entire wrap around the dry belt with the besaugbaren roller. Through the suction, the removal position of the Aufführstreifens and its orientation is fixed and thus enables a secure positioning relative to the removal device. The Besaugbarkeit serves In this case in function concentration different tasks, once the leadership of abzunehmenden leader strip and further the leadership of the web or the sub-strip of this in a catcher.

The provision of the provided for the transfer guide strip can be done in various ways. To this end, the material web can be subdivided in a first basic design into the last drying cylinder of the drying arrangement in the direction of passage of the drying belt or according to a second basic embodiment into the last drying cylinder, in particular between the discharge line of the drying belt from the last drying cylinder and the suctionable roll, and a residual web.

The first basic version includes a multitude of sub-variants, which are individually considered to be particularly suitable for certain applications. According to a first sub-variant, the subdivision of the material web is preceded by a first drying cylinder of the drying arrangement. The separation may be on the dry belt or supported on another movable surface. The separation can be done, for example, in a vertical arrangement of the drying cylinder on the top in the installed position deflection roller. The advantage of this design consists in the installation space available for the arrangement of the separator and the possibility of shifting into areas with correspondingly freely accessible space.

In a second sub-variant, the material web is subdivided between a deflection roller arranged upstream of the last drying cylinder in the direction of passage of the material web or circulation direction of the drying belt and the last drying cylinder. The separation preferably takes place in the looping area of the drying belt with the deflection roller. This sub-variant is characterized in that the possibility of Schnittgutaustragung with the dry belt with provision of an air knife in Cutting area and / or the arrangement of facilities for collecting the clippings is given.

In a further sub-variant, the separating position between the first and last drying cylinder of the drying arrangement is arranged.

The second basic embodiment of the separation of the Aufführstreifens only after the last in the direction of travel of the web or the direction of rotation of the drying belt drying cylinder offers the advantage of a short transfer path for the Aufführstreifen to the removal area on the besaugbaren roller. Measures on the drying belt to fix the Aufführstreifens on this before the acceptance area can be minimized or avoided altogether.

In all versions of a separation on the drying belt this is associated with a device for the cleaning of clippings and conditioning.

• zu - und/oder abschaltbar
• in Maschinenquerrichtung variabel einstellbar
• in Maschinenquerrichtung stufenlos oder in Zonen und Teilzonen einzeln und/oder in Gruppen oder gemeinsam
• in Umlaufrichtung des Trockenbandes stufenlos oder in Zonen und Teilzonen einzeln und/oder in Gruppen oder gemeinsam.

For optimum adaptation to the possible modes of operation in the transfer of the Aufführstreifens and / or management of the components of the web, the negative pressure in the removal area on the besaugbaren roller and / or on the dry belt in the area between drainage from the drying cylinder and besaugbarer roller and / or the expiration of the dry belt arranged downstream of the suctionable roller according to at least one of the following options:

• can be switched on and / or off
• variably adjustable in the cross machine direction
• in the cross-machine direction stepless or in zones and sub-zones individually and / or in groups or together
• in the direction of rotation of the dry belt continuously or in zones and sub-zones individually and / or in groups or together.

The adjustability is firstly an optimization of the required in the individual operations guides of web components, also the negative pressures are applied only when they are actually needed, so that the dry assembly is energy efficient operable.

• Führung eines Aufführstreifens von einer der Trockenanordnung vorgeordneten Funktionseinheit zur Trockenanordnung und durch diese;
• Führung des Aufführstreifens nach dem Ablauf des Trockenbandes vom in Umlaufrichtung des Trockenbandes letzten Trockenzylinder der Trockenanordnung mit dem Trockenband in Richtung einer Auffangeinrichtung;
• Ablösen des Aufführstreifens vom Trockenband und Übergang in die Auffangeinrichtung;
• Breitfahren der Materialbahn auf die gewünschte Breite unter Führung dieser in die Auffangeinrichtung;
• Unterteilung der Materialbahn in einen neuen Aufführstreifen und eine Restbahn
• Führung des neuen Aufführstreifens nach dem letzten Trockenzylinder mit dem Trockenband in einen Abnahmebereich;
• Überführung des neuen Aufführstreifens vom Abnahmebereich an eine der Trockenanordnung nachgeordnete Funktionseinheit unter Führung der Restbahn in die Auffangeinrichtung;
• Breitfahren der Materialbahn auf die gewünschte Breite.

An advantageous transfer of a material web to a functional unit arranged downstream of the drying arrangement is characterized in its entirety by subsequent method steps during commissioning or after a fault for the transfer of the material web:

• Guiding a Aufführstreifens of a dry arrangement upstream of the functional unit to the dry arrangement and by this;
• Guide the Aufführstreifens after the expiry of the dry belt from the last in the direction of rotation of the drying belt drying cylinder of the drying assembly with the drying belt in the direction of a catcher;
• Detaching the leader strip from the dry belt and transferring it to the catcher;
• Spreading the material web to the desired width while guiding it into the collecting device;
• Subdivision of the material web into a new leader strip and a residual web
• Guiding the new strip after the last drying cylinder with the drying belt into a removal area;
• Transferring the new Aufführstreifens from the pick-up area to a downstream of the drying assembly functional unit under the leadership of the residual web in the collecting device;
• Spreading the material web to the desired width.

In terms of apparatus, the drying device of a machine for producing a material web, in particular fibrous web in the form of a paper, board or tissue web with at least one drying arrangement and a Guide device for guiding the material web or a partial strip of the material web in a arranged below a portion of the drying arrangement catcher, wherein in the direction of passage of the drying device last drying arrangement comprises a plurality of drying cylinders and deflection rollers arranged therebetween and a drying belt for alternately guiding the web over the drying cylinder and guide rollers , And the guide device comprises a downstream in the direction of rotation of the drying belt last cylinder roller as a guide roll for the drying belt and at least one of these downstream further guide roller, which is arranged opposite to the last drying cylinder downstream roller, between the roller and the further guide roller perpendicular or opposite a vertical plane inclined to realize extending portion of the circulation path of the dry belt, wherein the collecting means below this portion of the Uml Aufweges is arranged, characterized in that the last drying cylinder downstream roller is looped above a characterized by its longitudinal axis and a perpendicular to this in a horizontal plane level of the dry belt, the guide means for holding the web or a partial strip of this on the dry belt to form a extending to the vertical or relative to a vertical plane inclined extending portion of the circulation path of the drying belt extending holding portion, comprising the last drying cylinder downstream roller in the form of a besaugbaren roller with at least one over at least a portion of the Umschlingungsbereiches of the dry belt with this circumferentially extending suction region ,

The embodiment of the invention offers the advantage of a secure guidance of the material web or a partial strip of these in a collecting device of dry arrangements, in which a decrease of these on the drying cylinder is not useful, for example, when taking against the direction of gravity. By the largely supported guidance in the direction of the catching device, this can be carried out with a small input cross-section.

The means for holding the material web or a partial strip advantageously additionally comprise a device for generating a negative pressure associated with the drying belt between the discharge line on the drying cylinder and the suctionable roller. The device stabilizes the material web or the partial strip on the drying belt in a simple manner.

In order to be able to guide the material web or the partial strip easily and safely into a collecting device, the transfer device comprises a device arranged downstream of the drying belt of the continuous line of the drying belt at the suctionable roller for applying a negative pressure. This stabilizes the material web or the partial strip in the form of a residual web with simultaneous transfer of a Aufführstreifens of the besaugbaren roller to the downstream functional unit or when discharging the Aufführstreifens in the catch this on the dry belt.

To ensure a transfer operation, a transfer device for a slit strip is provided, which utilizes components of the guide device in functional concentration. The decrease of the Aufführstreifens takes place on the suctionable roller from the dryer, whereby a firm acceptance position can be ensured. To release a Aufführstreifens in the removal area on the dry belt, the transfer device comprises a blowing device. The transfer takes place without ropes and precisely.

In a further development, the transfer device has one of the blowing device for releasing a transfer strip in the removal area on the drying belt downstream transfer device, in particular one or more parts executed and acted upon with vacuum tape to get the leader quickly under control and various web guides To take account of. The advantage of a multi-part belt, especially in the case of long transfer distances, is that the vacuum and thus the path deflection in the machine direction can be adapted.

In functional concentration while supporting the Aufführstreifens when guided on the dry belt after the discharge line of the drying belt from the drying cylinder on the drying belt between the discharge line on the drying cylinder and besaugbarer roller associated means for generating a negative pressure of the guide takes place.

In a particularly advantageous development, the dry belt between the discharge line on the drying cylinder and besaugbarer roller associated means for generating a negative pressure and the besaugbare roller at least one over the theoretical width of the Aufführstreifens extending zone and another parallel over the extension of the besaugbaren roller to the longitudinal axis extending zone, which are separated from each other and / or can be switched off.
As a result, in addition to guiding the performance strip, said device can also serve to stabilize the residual web as a partial strip of the material web.

Due to the separate connectivity and disconnection of the zones of the suction area and arranged between the drain line on the drying cylinder and besaugbarer roller means an energy-favorable mode of operation adapted to the specific mode of operation is possible because not always vacuum must be provided over the entire machine width.

• der Saugbereich der besaugbaren Walze beziehungsweise die diesen bildenden Zonen und/oder
• die Einrichtung zum Aufbringen eines Unterdruckes zwischen Ablauflinie am Trockenzylinder und besaugbarer Walze beziehungsweise die von dieser gebildeten Zonen und/oder
• die Einrichtung zum Aufbringen eines Unterdruckes zwischen besaugbarer Walze und nachgeordneter Leitwalze

in Umlaufrichtung des Trockenbandes und/oder quer zur Umlaufrichtung des Trockenbandes in zumindest eine, vorzugsweise mehrere Teilzonen unterteilbar, die einzeln und/oder in Gruppen oder gemeinsam ansteuerbar.
Durch die Unterteilbarkeit kann in Abhängigkeit der gewählten Teilung die Einstellung der Unterdrücke sehr feinfühlig über größere Bereiche in Maschinenquerrichtung erfolgen.To fulfill the different functions in the various modes of operation during a transfer operation are considered in its entirety

• the suction region of the suctionable roller or the zones forming it and / or
• the device for applying a negative pressure between the discharge line on the drying cylinder and the suctionable roller or the zones formed by this and / or
• the device for applying a negative pressure between besaugbarer roller and downstream guide roller

in the direction of rotation of the dry belt and / or transversely to the direction of rotation of the dry belt in at least one, preferably a plurality of subzones subdivided, the individually and / or in groups or jointly controllable.
Due to the divisibility can be done very sensitively over larger areas in the cross-machine direction depending on the selected division, the setting of the negative pressures.

In order to reduce the centrifugal forces acting on the material web in the event of demolition when guided on the suctionable roller, the suctionable roller has a diameter of> 700 mm, preferably in the range between 1200 mm and 1500 mm inclusive.

To ensure a short Überführweges while providing space for the removal of broke the besaugbare roller at a distance to the downstream functional unit, in particular next guide roll in the machine direction in the range between 3000 mm and 1500 mm, preferably 3000 mm and 2500 mm.

To provide the Aufführstreifens a separator for dividing the material web is provided in a Aufführstreifen and a residual web as a partial strip. This can be designed in various ways and be associated with the dry belt or a, the material web supporting the movable surface. The separation device can be characterized by the use of different separation media. For example, cutting devices in the form of air or water jet cutting devices are conceivable. The arrangement can be carried out upstream of the last drying cylinder of the drying arrangement, depending on the design and construction of the drying arrangement in a first basic design. In the immediate Vorordnung, preferably in Umschlingungsbereich this upstream diverting an air knife on the dry belt is arranged for Schnittgutabführung on the dry belt.

The separating device is arranged upstream of the first drying cylinder of the drying arrangement in a further sub-variant of the first basic version. The arrangement then takes place either at the beginning of the drying arrangement or a functional unit upstream of the drying arrangement.

In a second basic embodiment, the separator is downstream of the sequence of the drying belt from the last drying cylinder of the drying arrangement, preferably assigned in the wrap of the dry belt with the besaugbaren roller the dry belt, resulting in very short transfer paths to the removal area.

The drying apparatus is preferably designed and constructed in such a way that at least a portion of the drying cylinders in the end region of the last drying arrangement are arranged offset from one another in the vertical direction, wherein the longitudinal axes are free of offset in the machine direction to each other or offset in the machine direction to form a tilted relative to a vertical plane Dry arrangement are arranged. This design allows easy and quick removal of waste.

In an alternative embodiment, at least a part of the last drying arrangement is designed as an inverted single-row drying arrangement. The drying cylinders in the end region of the drying arrangement are arranged in the machine direction in a spaced row and the longitudinal axes of the intermediate idler rollers and the suctionable roller in the vertical direction above the longitudinal axes of the drying cylinder.

Figur 1

verdeutlicht eine Ausführung einer Trockenanordnung mit Führvorrichtung zur Überführung von Materialbahnbestandteilen in eine Auffangeinrichtung;

Figur 2

verdeutlicht anhand eines Signalflussbildes die eine Überführung der Materialbahn charakterisierenden Verfahrensschritte;

Figur 3

zeigt in schematisiert vereinfachter Darstellung eine Ausbildung einer Trenneinrichtung;

Figur 4

verdeutlicht unterschiedliche Anordnungsmöglichkeiten einer Trenneinrichtung;

Figuren 5a und 5b

zeigen eine mögliche Unterteilung des Saugbereiches der besaugbaren Walze in Umfangsrichtung und quer zu dieser;

Figur 6

verdeutlicht die Möglichkeit der Steuerbarkeit der einzelnen Einrichtungen zur Erzeugung eines Unterdruckes;

Figur 7

verdeutlicht eine unterteilte Ausführung eines Transferbandes;

Figur 8 und 9

zeigen mögliche Anordnungen der besaugbaren Walze gegenüber dem in Durchlaufrichtung der Materialbahn letzten Trockenzylinder;

Figur 10

zeigt eine mögliche Anordnung der Überführvorrichtung in einer invertierten einreihigen Trockenanordnung;

Figur 11

verdeutlicht beispielhaft mögliche Anordnungen der Trockenanordnung in einer Maschine zur Herstellung einer Materialbahn.

The solution according to the invention is explained below with reference to figures. The following is shown in detail:

FIG. 1

illustrates an embodiment of a drying arrangement with guide device for transferring material web components into a collecting device;

FIG. 2

illustrates the process steps characterizing a transfer of the material web on the basis of a signal flow diagram;

FIG. 3

shows a schematic simplified representation of an embodiment of a separating device;

FIG. 4

illustrates different possible arrangements of a separator;

FIGS. 5a and 5b

show a possible subdivision of the suction region of the suctionable roller in the circumferential direction and transversely thereto;

FIG. 6

clarifies the possibility of controllability of the individual devices for generating a negative pressure;

FIG. 7

illustrates a subdivided version of a transfer belt;

FIGS. 8 and 9

show possible arrangements of the besaugbaren roller against the last in the direction of travel of the web drying cylinder;

FIG. 10

shows a possible arrangement of the transfer device in an inverted single-row drying arrangement;

FIG. 11

exemplifies possible arrangements of the dry arrangement in a machine for producing a material web.

The FIG. 1 illustrates in schematic highly simplified representation of a section of a drying assembly 1 for use in machines for producing a fibrous web F in the form of a paper, board or tissue web the arrangement and operation of a guide device 34 according to the invention for guiding at least a partial strip of the fibrous web F, in particular a Aufführstreifens AS 'or a residual web RS or the entire fibrous web F' in a vertically offset catcher, in particular arranged below a portion of the drying arrangement pulper 18th FIG. 1 further clarifies the arrangement and operation of a transfer device 2 for a Aufführstreifen AS taking off a dry belt 3 and transfer to a downstream, the fibrous web F further processing or processing functional unit 4. In functional concentration components of the guide 34 and the transfer device 2 are formed of the same components , To illustrate the individual directions, a coordinate system is applied to the dry arrangement 1 by way of example. The X-axis describes the longitudinal direction of the extension of the machine and is therefore also referred to as the machine direction MD. This corresponds to the direction of passage of the material web through the machine for producing these. The Y direction describes the direction transverse to the machine direction and is therefore also referred to as the cross-machine direction CD. The Z direction corresponds to the height direction.

The drying arrangement 1 comprises at least one, preferably a plurality of drying cylinders TZ1 to TZn. The last drying cylinder TZn and TZn-1 shown in the feedthrough direction of the fibrous web F are shown by way of example. The fibrous web F is guided meandering alternately over the drying cylinders TZ1 to TZn and deflection rollers 5 arranged therebetween during normal operation of the drying arrangement 1 by an endlessly circulating drying belt 3 in the form of an air-permeable drying wire in the illustrated area of the drying arrangement 1. The guide is always supported on the dry belt 3. When re-commissioning the machine or after an interruption of the operation due to a fault, a new listing of the fibrous web F is required. For this purpose, a Aufführstreifen AS is transferred to the downstream functional unit 4 and driven after the transfer, the fibrous web to its desired width. Before the production of the performance strip AS For example, the fibrous web F is moved by the width of a pathway, in particular a pulper 18, downstream of the last drying cylinder TZn of the drying arrangement 1 in the direction of passage, which is arranged below the drying arrangement 1. Notwithstanding the web-width guidance, it is also possible to guide a partial strip in the form of a threading strip AS 'or a residual web RS into the catching device in accordance with the mode of operation of the drying arrangement. The guide of the fibrous web F or the partial strip is carried out according to the invention supported on the dry belt 3. To keep them in the direction of the catcher, means 36 are provided which define a holding portion 37 for the fibrous web or the partial strip on the dry belt 3 in the entirety of their mode of action. The means 36 and the holding portion 37 are part of the guide 34. The detachment of the fibrous web or the partial strip from the dry belt 3 takes place in a release area 35. The holding portion 37 extends over a portion of the circulation path of the dry belt 3, starting from a discharge line AL on the drying cylinder TZn to the release area 35.

The drying arrangement 1 is designed in such a way that, in the region upstream of the functional unit 4, it is suitable to dry only one side of the fibrous web F by contact drying. That is to say that this area is single-row, wherein the arrangement of the drying cylinders TZ1 to TZn can vary. FIG. 1 shows a section of a substantially vertical arrangement of the individual drying cylinders TZn-1 to TZn based on the installation position. The longitudinal axes L _TZn-1 to L _{TZn of} the individual drying cylinders TZn-1 to TZn extending in the installation position in the cross-machine direction CD are arranged parallel to one another and offset from one another in the vertical direction. The theoretical connecting line through the longitudinal axes of the drying cylinders TZn, TZn-1 is characterized by a straight line, which in FIG. 1 perpendicular to a horizontal plane. Arrangements are also conceivable which can be described by an inclination of the theoretical connecting line through the longitudinal axes of the drying cylinders TZn, TZn-1. In this case, the Arrangement of the drying cylinders considered with additional offset in the machine direction MD.

The fibrous web F is guided under direct contact with the lateral surface 10.1 to 10.n of the individual drying cylinders TZn-1 to TZn, each over a partial area of the outer circumference thereof. The deflection between two arranged in the direction of passage of the fibrous web F adjacent drying cylinders TZn-1 and TZn via the intermediate guide rollers 5. The individual guide rollers 5 are arranged between two adjacent in the direction of rotation of the drying belt 3 drying cylinders TZn, TZn-1, i. whose longitudinal axes are arranged offset to those of the drying cylinder in the vertical and horizontal directions. The guide rollers 5 are preferably designed as besaugbare guide rollers. The suction can be done either directly over the interior 11 of the guide rollers 5 or indirectly via the outer periphery 12 of the guide rollers 5 arranged suction boxes. The deflection rollers 5 are arranged inside the drying belt 3, i. The drying cylinders TZn-1 and TZn are arranged outside of the loop formed by the drying belt 3 and contact in non-operation with a portion of their lateral surfaces 10.n-1, 10.n the Outside of the dry belt 3 3. In operation of the dryer assembly 1, the drying belt 3 presses the fibrous web F against the surface formed by the lateral surface 10.n-1, 10.n of the respective drying cylinder TZn-1, TZn from, and thus improves the heat transfer to Fibrous web F.

In normal operation, the fibrous web F is guided on the outer side 15 of the drying belt 3. During the wrapping of the guide rollers 5, the fibrous web F is then at this outside, ie the surface of the guide rollers 5 contacted directly the dry belt 3. The jacket of the individual guide roller 5 is preferably designed in the illustrated embodiment with a perforation and the interior 11 with a not in detail connected vacuum source connected. To stabilize the web run are located in the pockets between the drying cylinders TZn-1 and TZn and the guide rollers 5 suction boxes 13, on the negative pressure of the fibrous web F between drying cylinder TZn-1 and guide roller 5 is sucked to the drying belt 3. It is also conceivable to use the suction boxes 13 additionally or alternatively to the suction of the inner space 11 of the respective guide roller 5.

The last in the guide direction of the fibrous web F drying cylinder TZ a guide roller for the dry belt 3 in the form of a besaugbaren roller 6 is arranged, which is arranged such that these viewed in the installation position at least over a portion of its outer periphery 7 above a plane E, through the longitudinal or rotation axis R of the suctionable roller 6 and a vertical in the horizontal plane or machine direction MD is characterized, is wrapped by the dry belt 3. In other words, the suctionable roller 6 must be wrapped in the region of its upper half in the installed position over at least a portion of its outer periphery 7 of the dry belt 3.

The transfer of a Aufführstreifens AS of the fibrous web F on the following functional unit 4 is not carried out here by the direct decrease in the drying cylinder, especially on the drying cylinder TZn but by acceptance on the dry belt 3 and transfer to a downstream functional unit 4. For this, the Aufführstreifen AS after the last drying cylinder TZn supported on the dry belt 3 out, ie after the discharge line AL of the drying belt 3 from the drying cylinder TZn supported on this. The decrease of the Aufführstreifens AS is then the discharge line AL of the dry belt 3 downstream of the drying cylinder TZn and before or in the region of a theoretical line, which by the intersection of the plane E and the dry belt. 3 is characterizable on the suctionable roller 6. To remove the Aufführstreifens AS from the dry belt 3, the transfer device 2 comprises a removal device 8, which may be designed in various ways. This is the dry belt 3 im Assigned to the acceptance area AB. As a take-off device 8 suction and / or blowing devices are used, which transfer the Aufführstreifen AS directly or indirectly via further transfer devices, for example in the form of a conveyor belt 9 to the next functional unit 4. The conveyor belt 9 is preferably designed as a vacuum belt. The design can be one or more parts.

If now a Aufführstreifen AS are transferred from the drying assembly 1 to the downstream functional unit 4, the Aufführstreifen AS is either already generated in a drying assembly 1 upstream functional unit and transferred to this or generated only in the dry assembly 1. Regardless of the type of production illustrated FIG. 1 an embodiment in which the Aufführstreifen AS after the end AL of the drying cylinder TZn further on the drying belt 3 to the besaugbaren roller 6, which is arranged spaced in the MD and z direction to the last drying cylinder TZn out. The guide can be safely ensured by applying the dry belt 3 on the side leading away from the leader strip AS side with a negative pressure, for example via a device 16. The decrease of the dry belt 3 takes place in a particularly advantageous manner on the besaugbaren roller 6 in the wrapping region of the dry belt 3 with this, in particular a region of the outer periphery 7 of the suctionable roller 6 above the plane formed by the axis of rotation R and perpendicular to this in the MD direction E. The acceptance range AB can ideally be described by a line running in the cross-machine direction CD. The acceptance area AB is in the in FIG. 1 in the view of this in the MD / Z plane of the machine or with respect to the plane E in an angular range between each including 0 ° and 180 °, preferably 0 ° and 90 ° arranged.

• in Maschinenrichtung im Bereich zwischen jeweils einschließlich 3000 mm und 1500 mm, vorzugsweise 3000 mm und 2500 mm

The besaugbare roller 6 is preferably designed with a diameter> 700mm, preferably in the range between 1200 mm to 1500 mm. The arrangement of the suctionable roller 6 with respect to the following functional unit 4 is preferably characterized by the following dimensional ranges:

• in the machine direction in the range between in each case including 3000 mm and 1500 mm, preferably 3000 mm and 2500 mm

FIG. 1 illustrates the necessary for the transfer operation of a Aufführstreifens AS facilities, in particular a the dry belt 3 after the flow line AL on the drying cylinder TZn associated with take-off device 8 and optionally further facilities, such as a conveyor belt 9. The transfer process only the Aufführstreifens AS designed as in the flowchart according to FIG. 2 as process steps VA to VC. The threading strip AS is removed from the drying belt 3 behind the discharge line AL at the last drying cylinder TZn, which also corresponds to the discharge line of the drying belt 3 from the drying cylinder TZn, and transported to the downstream functional unit 4 in method step VB. After the transfer, the fibrous web F can be driven to full width according to VC.

The mode of operation of the drying arrangement 1 as a whole during a transfer operation after an interruption in operation is designed as in the flowchart according to FIG FIG. 2 played. Upon detecting a variable which characterizes a malfunction in the mode of operation of the machine or an event impairing the mode of operation in accordance with a method step V0, the fibrous web F is discharged in a region upstream of the source of interference into a collecting device, in particular a pulper 18 and a new track of the fibrous web. Since the fibrous web F is usually not transferred in full width between the individual functional units of the machine, a Aufführstreifen AS ', preferably generated in the form of a marginal strip, which is guided by the individual successively arranged functional units of the machine until the fibrous web on again their full width can be driven. If such a threading strip AS 'is guided in a drying arrangement 1 with a suctionable roll 6 downstream of the last drying cylinder TZn in the manner described, this is not necessarily transferred immediately to the following functional unit 4, but into a drying unit 1 below arranged catcher, in particular a pulper 18 performed according to step V01. The guide is preferably ropeless. For this purpose, the area between the last drying cylinder TZn and the suctionable roll 6 and preferably also a drying roll 3 after the besaugbaren roller 6 leading guide roll 19 with a negative pressure, preferably a vacuum can be acted upon. The application can be realized by means arranged on the inside 14 of the drying belt 3 and the suctionable roller 6 downstream device 21 for applying a negative pressure. The guide roller 19 is disposed below the besaugbaren roller 6, preferably their spaced apart in the vertical direction longitudinal axes in the vertical direction in alignment, that is arranged free of offset in the MD direction. The guide roller 19 preferably has a smaller diameter than the suctionable roller 6, so that the drying belt 3 is guided at an angle with respect to the vertical direction between the suctionable roller 6 and guide roller 19, to allow easy removal of the Aufführstreifens AS 'in the pulper 18 , In order to keep the opening of the pulper 18 for effective pulper extraction as small as possible, the distance between the besaugbaren roller 6 to the next guide roller in the machine direction is selected such that it is in the range between each including 3000 mm and 1500 mm, preferably 3000 mm and 2500 mm ,

The opening of the pulper 18 is preferably closed by choice. This is closed during operation and opens automatically when demolished or by the weight of the reject. For feeding into the pulper 18 are also not here represented Pulperspritzrohre, which are arranged on both sides of the introduced into the pulper 18 partial strip or the fibrous web.

To prevent entrainment of the fibrous web F 'or partial strips of these, the guide roller 19 are provided in the direction of rotation of the dry belt 3 at this stripping means 38. Preferably, a Ablöseblasrohr 39 is provided which is arranged in the direction of rotation of the dry belt 3 in front of the guide roller 19 and the gusset between the drying belt 3 and guide roller 19 is applied, i. in the gusset between the rising dry belt and guide roll 19 blows. This serves to support the detachment of the fibrous web or a partial strip, in particular Aufführstreifens AS 'or the residual web RS.

The individual devices 16 and 21 can also be formed by one unit. In order to be able to use a negative pressure, in particular the vacuum, specifically at the required areas free from impairment of adjacent areas in the drying arrangement 1, said area is preferably sealed off from the environment surrounding it, for example by means of a corresponding cover plate 20.

After ensuring guided the Aufführstreifens AS 'in the pulper 18, the fibrous web is moved as fibrous web F' in step V02 to the desired width. The wide-traveling or end-to-end wide-spread fibrous web F 'is also guided on the drying belt 3 to the pulper 18 in step V03 out. The fibrous web F 'is acted upon by the negative pressure of the device 16 and the suctionable roller 6 to remain on the drying belt 3 until the expiration of the besaugbaren roller 6 and this downstream in the region between the besaugbaren roller 6 and the guide roller 19. Now, the actual Aufführstreifen AS is generated by the wide-traveled fibrous web F 'is divided into a Aufführstreifen AS and a residual web RS in V04. The Residual web RS is guided in the pulper 18 - V05 and the leader strip AS according to VA to VC in FIG. 2 transferred to the downstream functional unit 4 and the fibrous web F driven to desired width. The wide-traveled fibrous web F is then no longer guided in VD to the removal area AB on the besaugbaren roller 6 but raises according to the imaginary line connecting the downstream functional unit, for example, the transfer belt 9 earlier from the dry belt 3. This area is designated by 24 and is preferably within the Umschlingungsbereiches of the dry belt 3 with the besaugbaren roller 6 in front of the removal area AB for the Aufführstreifen AS. The transferred wide-traveled fibrous web F is shown by dash-dotted line.

For dividing the fibrous web F 'in a Aufführstreifen AS and a residual web RS a separator 17 is provided which allows a subdivision of the fibrous web F' within the dryer assembly 1 in a residual web RS and the aufzuführenden, ie the functional unit 4 to be supplied Aufführstreifen AS. According to the in FIG. 3 In the embodiment shown, the subdivision takes place in front of the last drying cylinder TZn in the direction of rotation of the drying belt 3 and the direction of passage of the fibrous web F, in particular between the deflection roller 5 and the drying cylinder TZn.

The separating device 17 can be designed in a variety of ways. Conceivable are concepts with cutting media in the form of a fluid, such as a double-head water jet tip cutter as well as a solid, such as a cutting blade. Depending on the design and the position, the width of the threading strip as well as the position of the threading strip in the CD direction can be varied.

FIG. 1 illustrates an advantageous arrangement of the separator 17. By means of this, the subdivision is carried out by separation of the fibrous web F 'on the dry belt 3. The separator 17 is for this purpose the outside of the Dry band 3 assigned. If the subdivision into the guide strip AS and the residual web RS takes place before the last drying cylinder TZ, if an air knife is provided in the region of the suction box 13 on the outside 15 of the drying belt 3, the cut material is discharged through the drying belt 3.

The FIG. 3 clarified in a view of the fibrous web F ', the arrangement of the separator 17 and its mode of action for subdivision into Aufführstreifen AS and residual web RS. The direction of movement of the fibrous web F 'is indicated by an arrow, likewise the directions of movement of the leader strip AS and the residual web RS. By way of example, the separating device 17 is displaceably mounted on a carrier 25 extending in the cross-machine direction CD in accordance with the double-headed arrow. About the position of the separator 17, the width of the Aufführstreifens AS can be varied in a simply cutting device. If this is designed as a double cutter, in addition to the width, the position of the Aufführstreifens AS can be varied in the cross machine direction CD. The setting can be made manually or automatically, for example by means of a corresponding control device 23, which activates an adjusting device of the separating device 17 as a function of a variable which at least indirectly characterizes the width of the threading strip AS and / or the position in the cross-machine direction CD.

The FIG. 4 shows on the basis of a section of a drying arrangement 1 according to FIG. 1 Other options for the arrangement of the separator 17, which can be used alternatively. The individual arrangements are designated 17.1 to 17.3. By way of example, a vertical arrangement of the drying arrangement 1 with several drying cylinders TZn, TZn-1, TZn-2 and TZn-3 is reproduced. All drying cylinders are arranged in the vertical direction with respect to their longitudinal axes free of misalignment in the MD direction.

Another first possible arrangement of the separator 17.1 is by an arrangement after the expiry of the dry belt 3 from the direction of rotation of the Drying belt 3 last drying cylinder TZn characterized. The fibrous web F 'to be subdivided is removed in this case with the drying belt 3 from the last drying cylinder TZn and subdivided downstream of the outflow AL into feeding strips AS and residual web RS, the division taking place before the suctionable roll 6. In this case, the cut is not influenced by the drying cylinders. The separating device 17.1 can also be arranged directly on the suctionable roller 6.

Another second possible arrangement of the separating device 17.2 is characterized by an arrangement at the beginning or in front of the drying arrangement 1, in particular the drying cylinder TZn-3 or the upstream deflection roller 5. This arrangement provides sufficient space for the arrangement of the separator 17.2.

The third possible arrangement of the separating device 17.3 is characterized by an arrangement within the drying arrangement 1 and upstream in the direction of rotation of the drying belt 3 last drying cylinder TZn.

Since after transferring the Aufführstreifens AS, the fibrous web F is driven wide and is no longer guided on the suctionable roller 6 to the removal area AB on the dry belt 3, the suction region 22, thus only for the transfer of Aufführstreifens AS and possibly the support of the leadership of the sub-strip , in particular Aufführstreifens AS ', the residual web RS or the fibrous web F' to catcher, in particular pulper 18 in cooperation with the device 21 is at least switched off to not affect the leadership of the fibrous web F to the functional device 4 in the normal operating state. The suction region 22 is preferably designed over the extent of the roller 6 in the cross-machine direction CD. The vacuum applied via the suction zone 22 can be infinitely or stepwise adjustable in the CD transverse direction CD. Exemplary is in FIG. 5a in a schematic simplified representation in one Settlement illustrated an embodiment of the suction region 22 in the cross-machine direction CD with a plurality of zones 22A to 22D. The individual zones can be controlled individually or in groups or jointly. Preferably, at least one of the zones, for example, the zone 22A is designed such that it corresponds to the width of the Aufführstreifens AS. Other subdivisions are conceivable. The remaining suction zones are arranged in the cross-machine direction and preferably extend over the entire width of a residual web RS theoretically to be acted upon by these. The individual zones can, viewed in the cross-machine direction CD in the installation position of the roller 6, vary in terms of their extent in the width direction.

Also conceivable is a subdivision of the suction region 22 in the circumferential direction of the roller 6, as in FIG FIG. 5b exemplified for the one zone 22A. This is subdivided into subzones 22A1 and 22A2. This subdivision can be made, for example, for all zones. It is also conceivable a different subdivision in the circumferential direction of the roller 6 and in the longitudinal direction, ie considered width direction in installation position in the machine.

In both versions according to the FIGS. 5a and 5b there is the possibility of controlling the zones 22A-22D, 22A1, 22A2 by means of a control device 23 in response to a corresponding setpoint specification X, for example in the form of a respective operating mode, in particular the respective step in the transfer at least indirectly characterizing size.

By analogy, the aforementioned embodiments for the suction region 22 also apply to the devices 16 and / or 21 for applying a negative pressure to the drying belt 3 according to the FIG. 6 , These can also be switched on and off. Furthermore, these can be subdivided in the cross-machine direction CD and / or along the guide path of the drying belt 3 into zones which can be controlled individually and / or in groups or jointly. The control can for example also take place via a control device 23.

The respective control device 23 may be a control device assigned to the respective functional group. Also conceivable is a control unit centrally assigned to a functional unit or to several or to the entire machine.

The FIG. 7 illustrates exemplified the execution of the conveyor belt 9 in a subdivided form, in particular in two-part design. For this purpose, the conveyor belt is subdivided by way of example into a subarea 9A and 9B.

The FIGS. 8 and 9 show further possible embodiments of the guide portion of the drying belt 3 to the suctionable roller 6. These designs are characterized by a short guide. FIG. 8 shows an embodiment in which the suctionable roller 6 has been moved with its axis of rotation R in the region of a vertical through the longitudinal axes L _{Tzn of} the drying cylinder TZn. This shortens the guide path for the dry belt 3 to the removal area AB. Although this embodiment does not allow arrangement of the separating device 17 downstream of the drying cylinder TZn, but can dispense with a device 16 for supporting the leadership of the sub-strip or the fibrous web on the dry belt 3 between drain AL from the drying cylinder TZn and besaugbarer roller 6.

Another possible execution is in FIG. 9 played. In this, the suctionable roller is arranged such that the suction region 22 of the suctionable roller 6 directly adjoins the discharge line AL. This arrangement is particularly suitable for embodiments in which the Aufführstreifen AS is created before the last in the direction of passage drying cylinder TZn the drying assembly 1.

FIG. 10 shows a possibility of using a method according to the invention and a transfer device 2 according to the above Embodiment and mode of operation in an inverted drying arrangement 1. This comprises a plurality of drying cylinders TZn, TZn-1 arranged in series with one another and deflection rollers 5 arranged therebetween, wherein the deflection rollers 5 and the downstream in the direction of rotation of the dry belt 3 and thus the direction of passage of the fibrous web F downstream besaugbare roller 6 in contrast to the previously described installation position with respect to their longitudinal axes above the longitudinal axes L _Tzn and L _Tzn-1 are arranged. The leadership of the sub-strip or the fibrous web in the collecting device and the transfer process of the Aufführstreifens AS takes place in analogy to in the FIGS. 1 to 9 described procedure. For the same elements, therefore, the same reference numerals are used and with respect to the transfer operation, reference is made to the previous statements.

FIG. 11 illustrates in schematically simplified representation on the basis of the exemplary construction of a machine 26 for producing a material web possible arrangements of the drying assembly according to the invention 1. The machine 26 comprises a forming unit 27 and press section 28 with a subsequent drying device, which is divided into a pre-and Nachrockenvorrichtung 30 and a reel 31. Between the pre-and post-drying device 30, a smoothing device 32 and an applicator 33 for applying glue and / or coating color is arranged. The drying device according to the invention can be used both in the pre-29 and in the after-drying device 30. The arrangement in the pre-drying device 29 has the advantage that the influence of the particular single-sided application on the curl of the fibrous web 1 can be at least partially compensated.

LIST OF REFERENCE NUMBERS

1

dry arrangement

2

Transfer device

3

dryband

4

functional unit

5

deflection rollers

6

suctionable roller

7

Outer circumference suctionable roller

8th

removal device

9

conveyor belt

10.n, 10.n-1

Lateral surface of drying cylinder

11

Interior deflection roller

12

Outer circumference deflection roller

13

suction boxes

14

Inside dry belt

15

Outside dry belt

16

Facility

17, 17.1, 17.2, 17.3

separator

18

pulper

19

guide roll

20

Cover plate

21

Facility

22

suction area

22A-22D, 22A1, 22A2

Zone

23

control device

24

Area

25

carrier

26

Machine for producing a material web

27

molder

28

press section

29

Vortrockenvorrichtung

30

Night dehydrator

31

retractor

32

calender

33

applicator

34

guiding device

35

release area

36

Means for holding the web or the partial strip on the dry belt

37

holding area

38

stripping

39

transfer blowpipe

AL

Drain line strip on the drying cylinder

FROM

pick-up area

AS ', AS

feed strip

e

level

F

Fibrous web

F '

in the catcher to be discharged fibrous web

L _TZ1 , L _TZn

longitudinal axis

R

axis of rotation

RS

residual web

TZn, TZn-1, TZn-2, TZn-3

drying cylinders

MD

machine direction

CD

CMD

Claims (25)

1. Method for transferring a material web, in particular a fibrous web (F) in the form of a paper, cardboard or tissue web from a drying arrangement (1) of a machine (26) for producing a material web of this type, in which machine (26) the material web, supported on an endlessly circulating drying belt (3), is guided in an alternating manner over a plurality of heatable drying cylinders (TZn, TZn-1, TZn-2, TZn-3), in direct contact with the surface thereof, and deflecting rollers (5) which are arranged in between, to a functional unit (4) which is arranged downstream of the drying arrangement (1), during commissioning or after a disruption by way of transfer of a threading strip (AS), in which method, in one method stage, at least one part strip of the material web is guided out of the drying arrangement (1) or the full web width of the material web is guided into a collecting device (18) which is arranged below the drying arrangement (1);
   the material web or the part strip of the material web, supported on the drying belt (3), being guided into the collecting device (18) downstream of the last drying cylinder (TZn) of the drying arrangement (1) in the running direction of the material web through the drying arrangement (1), the material web or the part strip of the material web being guided with the drying belt (3), after flowing from the last drying cylinder (TZn) in the running direction of the material web through the drying arrangement (1), on the said drying belt (3) over a holding region (37), which is formed by a part region of the circulating path of the drying belt (3), as far as a release region (35) which is characterized by the detaching of the material web or the part strip from the drying belt (3), the material web being held on the drying belt (3) by way of vacuum over at least one part region of the holding region (37),
   characterized
   in that the material web or the part strip is guided with the drying belt (3) within the holding region (37) over an evacuated roller (6) which is arranged downstream of the last drying cylinder (TZn), the evacuated roller (6) being arranged in such a way that, in the installed position, it is wrapped around by the drying belt (3) at least over a part region of the outer circumference (7) above a plane (E) which is characterized by the longitudinal axis (R) of the evacuated roller (6) and a perpendicular with respect thereto in a horizontal plane, and is of evacuated configuration over at least one part region of the wraparound region, preferably the entire wraparound region, and the material web is released from the drying belt (3) downstream of the evacuated roller (6) and is pulled into the collecting device (18).
2. Method according to Claim 1,
   characterized
   in that, between a flow line (AL) of the drying belt (3) from the last drying cylinder (TZn) and the evacuated roller (6), the material web or the part strip of the material web (AS) is held on the drying belt (3) by way of the application of a vacuum to the drying belt (3).
3. Method according to either of the preceding claims,
   characterized
   in that, after the release, the material web is pulled into the collecting device (18), for example by means of pulper spray pipes which are arranged on both sides of the material web.
4. Method according to one of the preceding claims,
   characterized
   in that, within or upstream of the drying arrangement (1) or downstream of the flow line (AL) of the drying belt (3) from the last drying cylinder (TZn) of the drying arrangement (1) in the running direction, a threading strip (AS) is produced by way of severing of the material web, and the threading strip (AS) is guided into the collecting device as a part strip of the material web.
5. Method according to one of Claims 1 to 3,
   characterized
   in that, within or upstream of the drying arrangement (1), a threading strip (AS) is produced by way of severing of the material web, and, downstream of the last drying cylinder (TZn) of the drying arrangement (1), the threading strip (AS) is guided, supported by the drying belt (3), as far as into the wraparound region of the drying belt (3) with the evacuated roller (6) which is arranged downstream of the last drying cylinder (TZn), is removed from the drying belt (3) in a removal region (AB) within the wraparound region, and is transferred to the functional unit (4) which is arranged downstream.
6. Method according to one of the preceding claims,
   characterized
   in that the vacuum in the holding region (37) and/or the vacuum in the removal region (AB) on the evacuated roller (6) and/or on the drying belt (3) in the region between the flow (AL) from the drying cylinder (TZn) and the evacuated roller (6) and/or arranged downstream of the flow (AL) of the drying belt (3) on the evacuated roller (6) can be set according to at least one of the possibilities stated below:

   - can be switched on and/or off

   - can be set variably in the machine transverse direction (MD)

   - individually and/or in groups or jointly in zones in the machine transverse direction (CD)

   - individually and/or in groups or jointly in zones in the circulating direction of the drying belt (3).
7. Method according to one of the preceding claims, having the following method steps during commissioning or after a disruption in order to transfer the material web to a functional unit (4) which is arranged downstream of the drying arrangement (1):

   - guiding of a threading strip (AS') from a functional unit which is arranged upstream of the drying arrangement (1) to the drying arrangement (1) and through the latter;

   - guiding of the threading strip (AS') as a part strip of the material web with the drying belt (3) downstream of the flow (AL) of the drying belt (3) from the last drying cylinder (TZn) of the drying arrangement (1) in the circulating direction of the drying belt (3) in the direction of the collecting device (18) according to one of Claims 1 to 5;

   - detaching of the threading strip (AS) from the drying belt (3) and transfer into the collecting device (18);

   - widening of the material web to the desired width with guiding of the said material web into the collecting device (18) according to one of Claims 1 to 5;

   - dividing of the material web into a new threading strip (AS) and a residual web (RS);

   - transferring of the new threading strip (AS) to the functional unit (4) which is arranged downstream of the drying arrangement (1) with guiding of the residual web (RS) as a part strip of the material web into the collecting device (18) according to one of Claims 1 to 5;

   - widening of the material web to the desired width.
8. Drying apparatus of a machine (26) for producing a material web, in particular a fibrous web (F) in the form of a paper, cardboard or tissue web having at least one drying arrangement (1) and a guiding apparatus (34) for guiding the material web or a part strip of the material web into a collecting device (18) which is arranged below a part region of the drying arrangement (1), the last drying arrangement (1) in the running direction of the drying apparatus comprising a plurality of drying cylinders (TZn, TZn-1, TZn-2, TZn-3) and deflecting rollers (5) which are arranged in between and a drying belt (3) for alternating guiding of the material web over the drying cylinders (TZn, TZn-1, TZn-2, TZn-3) and deflecting rollers (5), and the guiding apparatus (34) comprising, as guiding roller for the drying belt (3), a roller which is arranged downstream of the last drying cylinder (TZn) in the circulating direction of the drying belt (3), and at least one further guiding roller which is arranged downstream of the said roller and is arranged with respect to the roller which is arranged downstream of the last drying cylinder (TZn) so as to realize a part region of the circulating path of the drying belt (3) between the roller and the further guiding roller, which part region runs perpendicularly or in an inclined manner with respect to a vertical plane, the collecting device (18) being arranged below the said part region of the circulating path; the roller which is arranged downstream of the last drying cylinder (TZn) being wrapped around by the drying belt (3) above a plane (E) which is characterized by the longitudinal axis (R) thereof and a perpendicular with respect thereto in a horizontal plane, and the guiding apparatus having means for holding the material web or a part strip thereof on the drying belt (3) with the formation of a holding region (37) which extends as far as into the part region of the circulating path of the drying belt (3), which part region runs perpendicularly or in an inclined manner with respect to a vertical plane, characterized in that
   the means for holding the material web or a part strip thereof on the drying belt (3) comprise the roller which is arranged downstream of the last drying cylinder (TZn), in the form of an evacuated roller (6) with at least one suction region (22) which extends in the circumferential direction over at least one part region of the wraparound region of the drying belt (3) with the said evacuated roller (6).
9. Drying apparatus according to Claim 8,
   characterized
   in that the means for holding the material web or a part strip comprises a device (16) for generating a vacuum, which device (16) is assigned to the drying belt (3) between the flow line (AL) on the drying cylinder (TZ) and the evacuated roller (6).
10. Drying apparatus according to Claim 8 or 9,
    characterized
    in that the means for holding the material web or a part strip comprises a device (21) for applying a vacuum between the evacuated roller (6) and the guiding roller (19) which is arranged downstream thereof, which device (21) is assigned to the drying belt (3) such that it is arranged downstream of the flow line of the drying belt (3) on the evacuated roller (6).
11. Drying apparatus according to Claim 10,
    characterized
    in that the suction region (22) of the evacuated roller (6) and/or the device (16) for applying a vacuum between the flow line (AL) on the drying cylinder (TZn) and the evacuated roller (6) and/or the device (21) for applying a vacuum between the evacuated roller (6) and the guiding roller (19) which is arranged downstream thereof have/has, as viewed in the circulating direction of the drying belt (3) and/or transversely with respect to the circulating direction of the drying belt (3), at least one, preferably a plurality of zones which can be actuated individually and/or in groups or jointly.
12. Drying apparatus according to one of Claims 8 to 11,
    characterized
    in that the guiding apparatus comprises means for detaching the material web or the part strip of the material web from the drying belt (3) at the end of the holding region (37), in particular a blowing device which is arranged in the pocket between the drying belt (3) and the roller which is arranged downstream of the evacuated roller.
13. Drying apparatus according to one of Claims 8 to 12,
    characterized
    in that the drying belt (3) is assigned stripping devices (38) downstream of the holding region (37).
14. Drying apparatus according to one of Claims 8 to 13,
    characterized
    in that the evacuated roller (6) has a diameter of > 700 mm, preferably in the range between 1200 mm and 1500 mm inclusive.
15. Drying apparatus according to one of Claims 8 to 14,
    characterized
    in that a transferring apparatus (2) is provided for transferring a threading strip (AS) to a functional unit (4) which is arranged downstream, comprising a removal apparatus (8) for a threading strip (AS), which removal apparatus (8) is arranged with respect to the evacuated roller (6) so as to be suitable for being active on the threading strip (AS) in a removal region (AB) in the wraparound region of the drying belt (3) with the evacuated roller (6).
16. Drying apparatus according to Claim 15,
    characterized
    in that the transferring device (2) comprises a blowing device for detaching a threading strip (AS) in the removal region (AB) on the drying belt (3) and a transfer device (9) which is arranged downstream of the blowing device for detaching a threading strip (AS) in the removal region (AB) on the drying belt (3), in particular a belt which is configured in one piece or multiple pieces and can be loaded with vacuum.
17. Drying apparatus according to Claim 15 or 16,
    characterized
    in that the evacuated roller (6) is arranged at a spacing from the functional unit (4) which is arranged downstream of it, in particular the next guiding roller in the machine direction (MD) in the range between 3000 mm and 1500 mm inclusive in each case, preferably between 3000 mm and 2500 mm.
18. Drying apparatus according to one of Claims 8 to 17,
    characterized
    in that a severing device (17, 17.1, 17.2, 17.3) is provided for dividing the material web into a threading strip (AS) and a residual web (RS).
19. Drying apparatus according to Claim 18,
    characterized
    in that the severing device (17, 17.1, 17.2, 17.3) is assigned to the drying belt (3) or a movable surface which supports the material web.
20. Drying apparatus according to either of Claims 18 and 19, characterized
    in that the severing device (17.2, 17.3) is arranged so as to be upstream of the last drying cylinder (TZn) of the drying arrangement (1).
21. Drying apparatus according to Claim 20,
    characterized
    in that an air knife is arranged on the drying belt (3) in the region of the deflecting roller (5) which is arranged upstream of the last drying cylinder (TZn).
22. Drying apparatus according to one of Claims 18 to 21,
    characterized
    in that the severing device (17.2) is arranged so as to be upstream of the first drying cylinder (TZn-3) of the drying arrangement (1).
23. Drying apparatus according to Claim 18 or 19,
    characterized
    in that the severing device (17.1) is arranged downstream of the flow (AL) of the drying belt (3) on the last drying cylinder (TZn) of the drying arrangement (1), preferably is assigned to the drying belt (3) in the wraparound region of the drying belt (3) with the evacuated roller (6).
24. Drying apparatus according to one of Claims 8 to 23,
    characterized
    in that at least some of the drying cylinders (TZn, TZn-1, TZn-2, TZn-3) are arranged offset in the vertical direction with respect to one another in the end region of the drying arrangement (1), the longitudinal axes (L_TZ1, L_TZn) being arranged such that they are free from offset in the machine direction (MD) with respect to one another or are offset in the machine direction (MD) with respect to one another with the formation of a drying arrangement (1) which is configured so as to be inclined with respect to a vertical plane.
25. Drying apparatus according to one of Claims 8 to 23,
    characterized
    in that at least part of the drying arrangement (1) is configured as an inverted single-row drying arrangement, in such a way that the drying cylinders (TZn, TZn-1, TZn-2, TZn-3) are arranged in a row spaced apart in the machine direction (MD) in the end region of the drying arrangement (1), and the longitudinal axes of the deflecting rollers (5) which are arranged in between and of the evacuated roller (6) are arranged above the longitudinal axes (L_TZ1, L_TZn) of the said drying cylinders (TZn, TZn-1, TZn-2, TZn-3) in the vertical direction.

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