DE102023101608A1 - Machine and method for producing or treating a fibrous web - Google Patents

Abstract

The invention relates to a machine (10) and a method for producing or treating a fibrous web, in particular a paper or cardboard web, preferably a corrugated cardboard base paper web, comprising a wire section (12) and a press section (14) and a drying section (16), wherein a transfer section (90) is included between the press section (14) and the drying section (16), and wherein the drying section (16) comprises, immediately following the press section (14) and the transfer section (90), at least one first drying section (21) and subsequently at least one first single-row drying cylinder drying section (22), and wherein the transfer section (90) comprises at least one transfer belt (92, 93), arranged such that the fibrous web is transferred to the first drying section (21) at a first transfer point (214), and wherein the first single-row drying cylinder drying section (22) comprises at least one first drying wire (220) and a removal device (227) wrapped around the first drying screen (220), arranged such that the fibrous web is taken over from the first drying section (21) at a second transfer point (217). According to the invention, it is provided that the first drying section (21) comprises a large drying cylinder (211) and that the transfer section (90) forms a transfer section (91) and the at least one transfer belt (92, 93) is designed to be permeable to air

Description

The invention relates to a machine, in particular high-speed paper machines, for producing or treating a fibrous web, in particular a paper and cardboard web, preferably a corrugated cardboard base paper web, comprising a wire section, a press section and a drying section.
A transfer section is included between the press section and the drying section, and the drying section includes at least one first drying section immediately following the press section and the transfer section and subsequently at least one first single-row drying cylinder drying section, and the transfer section includes at least one transfer belt, arranged such that the fibrous web is transferred to the first drying section at a first transfer point, and the first single-row drying cylinder drying section includes at least one first drying wire and a removal device wrapped around the first drying wire, arranged such that the fibrous web is taken over from the first drying section at a second transfer point.

The invention also relates to a method for use in a machine according to the invention.

Conventional high-speed paper machines for paper and cardboard webs, preferably for corrugated cardboard base paper webs, usually have a closed web guide or web guide without free tension between the press section and the drying section. The paper web is taken over by a drying screen of the first drying section either from a transfer belt or a felt. Preferably, the paper web is taken off from a lower covering. This is also the case with machines for producing corrugated cardboard base paper. With such solutions that have been common up to now, corrugated cardboard base paper can be produced stably at machine speeds of over 1500 to a maximum of 1650 m/min. Stable here means production with a running time efficiency of > 90%.

The document EN 10 2020 111 2256 A1 and the document EN 10 2021 114 994 A1 , disclose possible embodiments of a high-speed paper machine for producing a fibrous web, in particular a paper and cardboard web, preferably a corrugated cardboard base paper web with a drying section. The embodiment comprises in the drying section at least one impingement air drying section or impingement flow drying section immediately after the press section, with which the underside of the fibrous web is dried and guided vertically upwards. By means of an impingement air or impingement flow dryer, the machine speed can be further increased by approx. 100 to 200 m/min to a maximum of 1850 m/min without loss of running time efficiency.

The document DE10 2017 118218 A1 discloses a machine and a method for producing one-side coated special paper with high requirements for the surface quality of the paper produced. Due to the high requirements, an MG smoothing Yankee cylinder with a large diameter and additional drying hoods is arranged after an initial pre-drying section, with smoothing taking place via a smoothing cylinder pressed against the MG smoothing Yankee cylinder and further drying to a dry content of 90% in order to achieve a so-called glazed fibrous web surface. The fibrous web is guided around the smoothing cylinder without a supporting belt and, due to the dry content of the special paper already achieved, is guided into a post-drying section in a free pull, without a transfer belt. The system concepts shown are suitable for a maximum production speed of up to 800 m/min, in special exceptional cases up to 1400 m/min.

The document DE10 2019 127104 A1 discloses a Yankee drying cylinder with a drying hood in a tissue machine for producing a light tissue web, preferably tissue webs have a basis weight of less than 60 g/m ^2. The tissue machine comprises the Yankee drying cylinder and the drying hood as the only drying section and are usually creped at the end of the drying section by a take-off doctor and transferred to the following machine section. This transfer takes place without any additional aids and the Yankee drying cylinder is also a so-called self-take-off drying cylinder.

However, the solutions mentioned so far have a number of disadvantages. For example, a solution with impingement drying sections requires a very complex structure with many components, a lot of installation space and a complex web guide. The components are also expensive to operate and to purchase and, at high speeds, quickly show signs of wear even after short operating times. In particular, drying screens and air-permeable transfer belts immediately after the press section quickly show signs of contamination, which cannot be completely removed during operation even by modern cleaning devices and can therefore lead to malfunctions, such as web breaks, and longer machine downtimes. The complex web guide with several drying screens also presents particular challenges in operation and the control of the machine, for example the individual drive groups that are always correctly coordinated with one another over a longer period of time.

Another disadvantage is that the transfer to the first, single-row drying cylinder sections often does not function correctly, since the fibrous web often cannot be sufficiently stabilized on the first drying cylinder and the drying cylinder section must be operated outside the optimal or most efficient operating point in terms of energy consumption and drying performance in order to get these problems under control.

The object of the invention is to provide a drying solution that is simpler in terms of complexity and cost, preferably for corrugated cardboard base paper webs, in high-speed paper machines with more than 1650 m/min up to 1850 m/min and to make the error-prone transfer area of the fibrous web between the machine sections or within the machine sections more robust, preferably against disturbances such as web breaks.

The object is achieved according to the invention by a machine and a method according to the independent claims. Further advantageous embodiments of the present invention can be found in the subclaims

The machine according to the invention is characterized in that the first drying section comprises a large drying cylinder and that the transfer section forms a transfer path and the at least one transfer belt is designed to be permeable to air.

In an alternative embodiment, the machine is characterized in that the large drying cylinder has a diameter greater than 3.5 m, preferably greater than 4.5 m, in particular less than or equal to 6.5 m.

In an alternative embodiment, the machine is characterized in that the large drying cylinder is free from wrapping around a drying screen and/or the transfer belt and comprises at least one drying hood.

In an alternative embodiment, the machine is characterized in that the large drying cylinder is wrapped by a first transfer belt and the wrap angle is less than or equal to 200°, preferably less than 90°, in particular less than 45°.

In an alternative embodiment, the machine is characterized in that the removal device of the first drying cylinder drying section is arranged such that the fibrous web is removed directly from a surface of the large drying cylinder at the second transfer point.

In an alternative embodiment, the machine is characterized in that the removal device is a suction guide roller or a web stabilizer, preferably a web suction box.

In an alternative embodiment, the machine is characterized in that at least one suction box, wrapped around the first drying fabric, is arranged directly before and/or after the removal device.

In an alternative embodiment, the machine is characterized in that a safety distance of greater than or equal to 0.3 m and less than or equal to 1.0 m, preferably between greater than or equal to 0.7 m and less than or equal to 0.8 m, is provided before the second transfer point and after one end of the drying hood in the first drying section.

The safety distance is advantageously characterized in that the fibrous web undergoes further drying of the underside of the fibrous web on the distance covered of up to 1.0 m before the transfer point to the subsequent first, single-row drying cylinder drying section. This safety distance makes it possible to further increase the fibrous web temperature from greater than or equal to 2°C to less than or equal to 4°C if the fibrous web temperature achieved for certain basis weights has not yet reached the desired main evaporation zone, which means a fibrous web temperature of greater than or equal to 60°C and less than or equal to 70°C, preferably greater than or equal to 65° and less than or equal to 70°C, in order to operate the subsequent first, single-row drying cylinder drying section at an optimal operating point.

In an alternative embodiment, the machine is characterized in that the transfer section comprises a first transfer belt and a first suction guide roller and at least one, preferably two to five, support roller(s) and/or at least one, preferably two to four, stabilizer(s) and that the first transfer belt wraps around the first suction guide roller and the at least one support roller and/or the at least one stabilizer.

Advantageously, the holding force required to hold the fibrous web on a transfer belt is provided by a stabilizer that works with a vacuum, preferably negative pressure. sators, preferably transfer foils or suction boxes.

The supporting or load-bearing transfer belts of the fibrous web must remain permeable to air without any reduction. If they become dirty, particularly when high proportions of >80% recycled raw materials are used, such as waste paper, the screen cleaning systems that are usually used often cannot keep them permeable to air over the long term. If they become dirty, the fibrous web can no longer hold, particularly if the fibrous web has to be transported hanging. The weight of the fibrous web detaches it from the transfer belt. Disruptions during the fibrous web transfer very often result in the fibrous web breaking off and thus longer and costly production downtime.

In an alternative embodiment, the machine is characterized in that the transfer section comprises a second suction guide roller wrapped around the first transfer belt, arranged such that the fibrous web is transferred from the first transfer belt to a transfer point to the first drying section, and that the transfer section forms a hanging transfer section or a twin-wire transfer section.

In an alternative embodiment, the machine is characterized in that the transfer section comprises a second transfer belt, arranged such that the transfer section forms a twin-wire transfer section.

In an alternative embodiment, the machine is characterized in that the twin-wire transfer section is arranged in such a way that it is concavely curved downwards and that the first transfer belt is guided above the fibrous web and the second transfer belt is guided below the fibrous web.

Advantageously, a twin-wire transfer section is concavely curved downwards, since the web guide which is concavely curved downwards enables the second transfer belt to lie wrinkle-free and reduces different transfer belt speeds, so-called differential speeds, to a minimum, especially compared to a convex or straight guide of the transfer belts.

In an alternative embodiment, the machine is characterized in that the transfer section comprises exactly one stabilizer, which is designed as a transfer foil.

A twin-wire transfer section is advantageously designed in such a way that almost no holding vacuum is required for the fibrous web along the transfer section, which requires the use of only one transfer foil. The transfer section advantageously only comprises support rollers and a transfer foil.

Advantageously, with only one transfer foil, the vacuum itself is generated by an air jet pump effect on the transfer foil. This makes it possible to achieve low negative pressures of up to 100 Pa.

In an alternative embodiment, the machine is characterized in that the transfer section comprises a second suction guide roller wrapped by a second transfer belt, arranged such that the fibrous web is transferred from the second transfer belt to a transfer point to the first drying section, and that the transfer section comprises a horizontal transfer section.

In an alternative embodiment, the machine is characterized in that the transfer section comprises at least one impingement dryer and/or steam blower box, arranged such that the fibrous web is additionally dried or heated in the transfer area supported by the first transfer belt.

Advantageously, the impingement flow drying sections enable a high temperature of the fibrous web to be achieved at the beginning of the single-row drying cylinder drying sections, thus enabling a very high machine production speed of over 1600 m/min.

In a further possible embodiment, the machine is characterized in that the machine is suitable for producing a fibrous web at a production speed of more than 1500 m/min, in particular more than 1650 m/min, particularly preferably more than 1850 m/min.

In a further possible embodiment, the machine is suitable for producing a fibrous web with a basis weight in the range from 60 g/m ² to 200 g/m ² , in particular in the range from 70 g/m ² to 100 g/m ² . This embodiment is particularly suitable for the production of corrugated cardboard base paper webs, preferably corrugated cardboard base paper webs of the new generation, which are characterized by very low basis weights in the range between 60 g/m ² and 100 g/m ² .

In a further possible embodiment, the machine is suitable for producing a fibrous material web from a fiber suspension with a proportion of fresh fibers, in particular wood pulp, cellulose or annual plants and a proportion of recycled fibers, preferably waste paper, between 50% and 100%, in particular greater than 50%. This embodiment is particularly suitable for the production of corrugated cardboard base paper webs with a high proportion of waste paper.

In a further possible embodiment, the machine is suitable for producing a fibrous web from a fibrous suspension with a proportion of recycled fibrous material, preferably waste paper, of 100%.

In a further alternative embodiment, the machine is characterized in that the last press nip of the press section is extended in the web travel direction, wherein it is preferably formed by a shoe press nip and the shoe press nip is formed between an upper shoe press roll, a felt and a lower counter roll wrapped by the lower covering.

Advantageously, the press section is designed in such a way that a high level of dewatering of the fibrous web can be achieved before transfer to the first drying section, which reduces thermal energy consumption.

The last press nip of the press section is advantageously extended in the direction of web travel, and is preferably formed by a shoe press nip. Such an extended or shoe press nip results in greater and more efficient dewatering of the fibrous web.

In a further alternative embodiment, the machine is characterized in that the press section comprises at least two further press nips in addition to the last press nip, wherein two counter rollers are preferably assigned to a central press roller wrapped by a rotating upper press felt to form a first press nip and a second press nip following it in the direction of web travel, and the fibrous web is guided between the rotating upper press felt and a rotating lower press felt through the first press nip and between the upper rotating press felt wrapped around the central press roller and the rotating lower covering of the last press nip of the press section through the second press nip. This design of the press section thus ensures optimal dewatering of the fibrous web.

The method according to the invention is characterized in that the fibrous web is guided from the press section over a transfer section, and that the fibrous web is guided on a surface of a large drying cylinder in a first drying section, and that its underside is dried by the surface of the large drying cylinder and its upper side is dried by at least one drying hood, and that the fibrous web is taken over by a take-off device included in the subsequent first, single-row drying cylinder drying section at a second transfer point.

In an alternative embodiment, the method is characterized in that the fibrous web is taken over at a temperature of greater than or equal to 60°C and less than or equal to 70°C, preferably greater than or equal to 65° and less than or equal to 70°C, at the second transfer point, so that the subsequent first, single-row drying cylinder drying section is operated from the first drying cylinder at an optimal operating point, preferably the main evaporation zone.

The fibrous web is advantageously removed in a temperature range of greater than or equal to 60°C and less than or equal to 70°C, preferably greater than or equal to 65° and less than or equal to 70°C, preferably essentially 65°C. Maintaining the temperature is crucial for good runnability of the drying section. Due to the significantly increased web temperature in the first drying section, the adhesive force on the surface of the large drying cylinder drops significantly. This significantly reduces the necessary web removal forces or the web tension, which are required for transfer to the following first, single-row drying cylinder drying section. This enables stable operation at high speed, despite reduced web strength.

The invention expressly also extends to such embodiments which are not given by combinations of features from explicit references to the claims, whereby the disclosed features of the invention - as far as this is technically reasonable - can be combined with one another.

Corresponding elements of the embodiments in the figures are provided with the same reference numerals. The functions of such elements in the individual figures correspond to one another unless otherwise described and unless contradictions arise. A repeated description is therefore omitted.
It is also pointed out that the differing features of the embodiments shown can be exchanged for one another and combined with one another. The invention is therefore not limited to the combination of features shown. combinations of the embodiments shown.

Further features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the drawings.

• 1 zeigt einen Ausschnitt einer Ausführungsform einer Maschine 10 mit einem umschlingungsminimierten, großen Trockenzylinder 211 und mindestens einer Trockenhaube 212, wobei die Transfersektion 90 eine Doppelsieb-Transferstrecke 91 mit einem ersten Transferband 92 ausbildet und einer Abnahmevorrichtung 227 des ersten Trockenzylindertrocknungsabschnitts 22 als Saugleitwalze 227;
• 2 zeigt einen Ausschnitt einer alternativen Ausführungsform einer Maschine 10, mit einem umschlingungsminimierten, großen Trockenzylinder 211 und mindestens einer Trockenhaube 212, wobei die Transfersektion 90 eine Transferstrecke 91 mit hängender Faserstoffbahn ausbildet und einer Abnahmevorrichtung 227 als Saugleitwalze 227 mit geänderter Trockensiebführung 220;
• 3 zeigt einen Ausschnitt einer alternativen Ausführungsform einer Maschine 10, mit einem umschlingungsminimierten, großen Trockenzylinder 211 und mindestens einer Trockenhaube 212, wobei die Transfersektion 90 eine Transferstrecke 91 mit liegender Faserstoffbahn ausbildet und einer Abnahmevorrichtung 227 als Bahnstabilisator 227;
• 4 zeigt einen Ausschnitt von drei alternativen Ausführungsformen 92, 92' 92'' einer Maschine 10, mit erstens einem umschlingungsminimierten, großen Trockenzylinder 211, wobei die Transfersektion 90 eine Transferstrecke 91 mit hängender Faserstoffbahn ausbildet und zweitens und drittens zwei alternativen Ausführungsformen mit einem durch das erste Transferband 92`, 92" umschlungenen großen Trockenzylinder 211.

In the following, the invention is explained using four figures:

• 1 shows a section of an embodiment of a machine 10 with a large drying cylinder 211 with minimal wrap and at least one drying hood 212, wherein the transfer section 90 forms a twin-wire transfer section 91 with a first transfer belt 92 and a removal device 227 of the first drying cylinder drying section 22 as a suction guide roller 227;
• 2 shows a section of an alternative embodiment of a machine 10, with a large drying cylinder 211 with minimized wrap and at least one drying hood 212, wherein the transfer section 90 forms a transfer section 91 with a hanging fibrous web and a removal device 227 as a suction guide roller 227 with modified drying wire guide 220;
• 3 shows a section of an alternative embodiment of a machine 10, with a large drying cylinder 211 with minimized wrap and at least one drying hood 212, wherein the transfer section 90 forms a transfer section 91 with a lying fibrous web and a removal device 227 as a web stabilizer 227;
• 4 shows a section of three alternative embodiments 92, 92'92'' of a machine 10, with firstly a large drying cylinder 211 with minimal wrapping, wherein the transfer section 90 forms a transfer section 91 with a hanging fibrous web and secondly and thirdly two alternative embodiments with a large drying cylinder 211 wrapped by the first transfer belt 92`, 92".

The 1 a section of an exemplary embodiment of a machine 10 for producing or treating a fibrous web, which can in particular be a paper or cardboard web, preferably a corrugated cardboard base paper web. The machine 10 comprises a wire section 12, a press section 14 and a drying section 16.

In the illustrated section of the machine 10, the drying section 16 is also referred to as a so-called pre-drying section 16, which is usually supplemented in a machine 10 by subsequent further machine sections, such as a surface sizing section, a coating section, a post-drying section and/or a reeling section, which are not shown in the figures.

The "underside" of the fibrous web is the side of the fibrous web that comes into contact with a lower wire during its production within the machine and is removed from the lower wire. In the machine 10 shown, this is a forming wire 60 of a wire section 12.

The drying section 16 further comprises a first drying section 21, and subsequently at least one first, single-row drying cylinder drying section 22.

The drying section 16 comprises a first drying section 21, wherein the first drying section 21 comprises a large drying cylinder.

The drying section 16 comprises, as in 1 shown, a first single-row drying cylinder drying section 22, which directly and immediately follows the first drying section 21.

However, in alternative embodiments, the drying section 16 can also comprise, for example, several, preferably a second and/or a third and/or fourth, drying cylinder drying sections; in particular, a two-row drying cylinder drying section can also follow.

The machine or web running direction is indicated in the figure with “L”.

The last press nip 53 of the press section 14 is extended in the web running direction L and in the present case is formed by a shoe press nip 53.

In the illustrated embodiment, this shoe press nip 53 is formed between an upper shoe press roller 54, which is wrapped by an upper covering 63, preferably an upper press felt 63, and an underlying counter roller 58 of a shoe press, which is wrapped by a lower covering 40.

To improve the dewatering performance, the fibrous web guided together with the lower fabric 40 around the counter roll 58 of the shoe press roll 54, 58 is in the area of the counter roller 58 in front of the shoe press nip 53 is subjected to the steam of at least one steam blower box 50, which can in particular be a high-performance steam blower box.

In addition to the last press nip 53, the press section 14 comprises, for example, two further press nips 51, 52. In the present case, two counter rollers 56, 57 are assigned to a central press roller 55 wrapped by a rotating upper press felt 61 to form a first press nip 51 and a second press nip 52 following it in the web travel direction L. The fibrous web is guided between the rotating upper press felt 61 and a rotating lower press felt 62 through the first press nip 51 and between the upper rotating press felt 61 wrapping around the central press roller 55 and the rotating lower covering 40 of the last press nip 53 of the press section 14 through the second press nip 52.

For example, a suction press roller can be provided as the central press roller 55.

However, designs are also conceivable in which an additional shoe press is used on the roller 58. Such a solution for a press arrangement is described, for example, in the document EN 10 2016 123 2203 A1 disclosed.

In the present case, the fibrous web is taken over by a forming wire 60 of the wire section 12 through the upper press felt 61 wrapping around the central press roller 55.

Following the last press nip 53 of the press section 14, the fibrous web is taken over by a first circulating transfer belt 92 of the transfer section 90, in the area of a first suction guide roller 97 wrapped around by the first transfer belt 92, by a circulating lower clothing 40 guided through the last press nip 53 of the press section 14.

The fibrous web is then guided together with the first transfer belt 92 of the transfer section 90 along a twin-wire transfer section 91 in a generally horizontal manner.

After the fibrous web has been taken over by the first suction guide roller 97, the first transfer belt 92 is guided over a twin-wire transfer section 91 to a second suction guide roller 98. The fibrous web is guided partially suspended in this area and at least one, preferably two, preferably three, preferably four, preferably five, support roller(s) 94 and at least one, preferably two, preferably three, preferably four, stabilizers 95, 96, preferably at least or exactly one transfer foil 95, are provided for further stabilization.

In the 1 In the alternative embodiment shown, the twin-wire transfer section 91 comprises a second transfer belt 93, arranged such that the fibrous web is guided and stabilized on the section between the first suction guide roller 97 and the second suction guide roller 98 between the first transfer belt 92 and the second transfer belt 93, preferably as a so-called twin-wire guide 91 or sandwich guide 91.
Advantageously, the transfer section 91 between the first suction guide roller 97 and the second suction guide roller 98 is concavely curved downwards, which has an advantageous effect on the web tensions to be adjusted and the stabilization of the fibrous web.

There are 1 five support rollers 94 and a stabilizer 95, preferably exactly one transfer foil 95. The fibrous web is deflected by the second suction guide roller 98, which is also wrapped by the first transfer belt 92, to the large drying cylinder 211 of the first drying section 21 and the fibrous web is subsequently transferred from the first transfer belt 92 to the surface of the large drying cylinder 211 at a transfer point 214.

The first drying section 21 comprises one, preferably exactly one, large drying cylinder 211, on which the fibrous web is guided and dried freely, i.e. without a drying screen, on the surface.

The large drying cylinder 211 is connected to a steam and condensate system of the machine 10 and is heated with steam from the inside and with a steam temperature of greater than or equal to 120°C and less than or equal to 180°C. The internal pressure of the large drying cylinder is less than or equal to 8 bar, preferably less than or equal to 6 bar, compared to the environment.

For the longest possible drying section of the first drying section 21, which extends between a starting point of the drying section 214 and an end point of the drying section 215, the large drying cylinder 211 is advantageously designed with a diameter greater than 3.5 m, preferably greater than 4.5 m, in particular less than or equal to 6.5 m. The fibrous web temperature at the starting point 214 is usually essentially 40°C and at the end point 215 essentially 70°C. The first drying section 21 is designed in such a way that heating of the fibrous web of at least 25°C and a maximum of 50°C can be achieved.

For additional heating or drying, the first drying section 21 further comprises at least one, preferably two, drying hood(s) 212, arranged such that the drying hood 212 dries the fibrous web on the opposite side of the drying section on the large drying cylinder 211. This means that the fibrous web is dried on both sides.
The drying hood 212 is advantageously designed as a hot air drying hood 212. The hot air or blowing air is blown onto the fibrous web at a temperature between greater than or equal to 250°C and less than or equal to 400°C. The speed of the hot air or blowing air is between greater than or equal to 80 m/s and less than or equal to 110 m/s.

The first drying section 21 further comprises at least one removal scraper 218 arranged on the large drying cylinder 211. The removal scraper 218 enables a clean detachment of a transfer strip and/or a fibrous web adhering to the large drying cylinder 211 and guides them into a pulper located below.

Following the first drying section 21, the fibrous web is taken over from the surface of the large drying cylinder 211 by a first, rotating drying screen 220 of the first single-row drying cylinder drying section 22. The takeover takes place in the area of a removal device 227 of the first drying cylinder drying section 22, which is wrapped around the first drying screen 220, wherein 1 a possible embodiment is shown as a suction guide roller 227.

The first, single-row drying cylinder drying section 22 comprises 1 for example, three drying cylinders 221, 222, 223 located above, deflection suction rollers 225 located below and web stabilizers 224 subjected to negative pressure, around which the first drying wire 220 is guided. The fibrous web is dried from its underside and guided with the first drying wire 220. The first, single-row drying cylinder drying section 22 comprises at least a first drying cylinder 221 and a last drying cylinder 223, whereby any number of drying cylinders and/or further drying cylinder drying sections can be included depending on the drying requirements.

2 shows a section of an alternative embodiment of a machine 10, with a large drying cylinder 211 with minimal wrapping and two drying hoods 212, wherein the transfer section 90 forms a transfer section 91 with a hanging fibrous web and a removal device 227 as a suction guide roller 227 with a modified drying screen guide 220, wherein the 1 equally applicable features are not discussed repeatedly.
2 shows a transfer section 90 with a transfer section 91 with a hanging fibrous web and a removal device 227 of the first drying cylinder drying section 22, which is designed as a suction guide roller 227, with a modified drying wire guide 220.

In 2 Following the last press nip 53 of the press section 14, the fibrous web is taken over by a first circulating transfer belt 92 of the transfer section 90, in the region of a first suction guide roller 97 wrapped around by the first transfer belt 92, by a circulating lower clothing 40 guided through the last press nip 53 of the press section 14.

The fibrous web is then guided together with the first transfer belt 92 of the transfer section 90 along a hanging transfer path 91 in a generally horizontal manner.

After the fibrous web has been taken over by the first suction guide roller 97, the first transfer belt 92 is guided over a hanging transfer section 91 to a second suction guide roller 98. The fibrous web is guided in a hanging manner in this area and, for further stabilization, at least one, preferably two, preferably three, preferably four, preferably five, support roller(s) 94 and at least one, preferably two, preferably three, preferably four, stabilizer(s) 96 subjected to negative pressure, preferably suction boxes 96 subjected to negative pressure, are provided.
In the 2 In the alternative embodiment shown, the transfer path 91 between the first suction guide roller 97 and the second suction guide roller 98 is concavely curved downwards.

There are 2 two support rollers 94 and three stabilizers 96, preferably three suction boxes 96 which can be subjected to negative pressure. The fibrous web is deflected by the second suction guide roller 98, which is also wrapped around the first transfer belt 92, to the large drying cylinder 211 of the first drying section 21 and the fibrous web is subsequently transferred from the first transfer belt 92 to the surface of the large drying cylinder 211 at a transfer point 214.

In an alternative embodiment, as in 2 shown, the first single row tro In the spin cylinder drying section 22, immediately before and/or after the suction guide roller 227, one or two further stabilizers 228, preferably a suction box 228 subjected to negative pressure, which enable a first stabilization of the fibrous web before the first drying cylinder 221. The guidance of the first drying screen 220 is as in 2 shown, adapted to the other stabilizers 228.

3 shows a section of an alternative embodiment of a machine 10, with a wrap-minimized, large drying cylinder 211 and at least one drying hood 212, wherein the transfer section 90 forms a transfer section 91 with a lying fibrous web and a removal device 227 as a web stabilizer 227, wherein the 1 equally applicable features are not discussed repeatedly.
3 shows a transfer section 90 with a transfer section 91 with a lying fibrous web and a removal device 227 of the first drying cylinder drying section 22, which is designed as a web stabilizer 224.

As in 3 As shown, the fibrous web is taken over by a first circulating transfer belt 92 of the transfer section 90, following the last press nip 53 of the press section 14, in the region of a first suction guide roller 97 wrapped around by the first transfer belt 92, by a circulating upper clothing 63 guided through the last press nip 53 of the press section 14.

The fibrous web is then guided together with the first transfer belt 92 of the transfer section 90 along a lying transfer path 91 in a generally horizontal manner.

After the fibrous web has been taken over by the first suction guide roller 97, the first transfer belt 92 is guided over a horizontal transfer section 91. In this area, the fibrous web is guided lying on the first transfer belt 92 and is guided over at least one, preferably two, preferably three, preferably four, preferably five, support roller(s) 94 and at least one, preferably two, preferably three, preferably four, stabilizer(s) 96 subjected to negative pressure for further stabilization.

In an alternative embodiment, as in 3 As shown, the transfer section 90 comprises a second transfer belt 93 which wraps around a second suction guide roller 98, arranged such that the fibrous web is transferred to the second transfer belt 93 in the region of the second suction guide roller 98.

There are 3 two support rollers 94 and three stabilizers 96, preferably suction boxes 96 subjected to negative pressure. The fibrous web is deflected by the second suction guide roller 98, which is wrapped around the second transfer belt 93, to the large drying cylinder 211 of the first drying section 21 and the fibrous web is subsequently transferred from the second transfer belt 93 to the surface of the large drying cylinder 211 at a transfer point 214.

The transfer section 91 can optionally comprise an impingement flow dryer 99 arranged above the fibrous web or a steam blower box 99, which can advantageously additionally pre-dry or heat the fibrous web.

In an alternative embodiment, as in 3 As shown, the first single-row drying cylinder drying section 22 comprises a removal device 227, which is designed as a web stabilizer 224, preferably as a web suction box 224 subjected to negative pressure. The removal device 227, which is designed as a web stabilizer 224, preferably a web suction box 224, is immediately followed by a suction deflection roller 225 in front of the first drying cylinder 221, which together enable a first stabilization of the fibrous web in front of the first drying cylinder 221. The guidance of the first drying screen 220 is as in 3 shown, adapted to the removal device 227, preferably a web stabilizer 224, in particular web suction box 224.

4 shows a section of three alternative embodiments 92, 92`, 92" of a machine 10, with firstly a large drying cylinder 211 with minimal wrapping, wherein the transfer section 90 forms a transfer section 91 with a hanging fibrous web with a transfer belt 92 and secondly and thirdly two alternative embodiments with a large drying cylinder 211 wrapped by the first transfer belt 92`, 92", wherein the 1 equally applicable features are not discussed repeatedly.

4 shows a transfer section 90 with a transfer section 91 with a hanging fibrous web and a removal device 227 of the first drying cylinder drying section 22, which is designed as a suction guide roller 227, with a modified drying wire guide 220 compared to 1 .

In 4 the fibrous web is guided after the last press nip 53 of the press section 14 by a first circulating transfer belt 92 of the transfer section 90, in the area of a first Suction guide roller 97 is taken over by a rotating lower clothing 40 guided through the last press nip 53 of the press section 14.

The fibrous web is then guided together with the first transfer belt 92 of the transfer section 90 along a hanging transfer section 91, generally in a V-shape, first downwards to a further suction guide roller 98', by the further suction guide roller 98' the fibrous web is deflected and guided upwards again.

After the fibrous web has been taken over by the first suction guide roller 97, the first transfer belt 92 is guided over a hanging transfer section 91 and over a further suction guide roller 98' to a second suction guide roller 98. The fibrous web is guided in a hanging manner in this area and, for further stabilization, at least one, preferably two, preferably three, preferably four, preferably five, support roller(s) 94 and at least one, preferably two, preferably three, preferably four, stabilizer(s) 96 subjected to negative pressure, preferably suction boxes 96 subjected to negative pressure, are provided between the first (97) and second (98) suction guide rollers.

In the 4 In the alternative embodiment shown, the transfer path 91 between the first suction guide roller 97 and the further suction guide roller 98`, as well as between the further suction guide roller 98` and the second suction guide roller 98 is concavely curved downwards.

There are 4 two support rollers 94 and four stabilizers 96, preferably three suction boxes 96 which can be subjected to negative pressure.

Furthermore, in the transfer area 91 on the side opposite the transfer belt 92 and the fibrous web, at least one impingement flow dryer 99, for example two additional impingement flow dryers 99 as shown, is arranged for additional preheating of the fibrous web.

In the 4 In the first alternative embodiment 92 contained in the invention, the fibrous web is diverted to the large drying cylinder 211 of the first drying section 21 by the second suction guide roller 98, which is also wrapped around by the first transfer belt 92, and the fibrous web is then transferred from the first transfer belt 92 to the surface of the large drying cylinder 211 at a transfer point 214 and the transfer belt is guided away from the large drying cylinder 211 immediately after the transfer point 214. The large drying cylinder 211 is thereby minimally wrapped around by the first transfer belt 92.
In this variant, an optional arrangement of at least one, preferably two drying hoods 212 on the large drying cylinder 210 is conceivable.

In the 4 In the second alternative embodiment 92' contained in the second suction guide roller 98, which is also wrapped around by the first transfer belt 92, the fibrous web is deflected to the large drying cylinder 211 of the first drying section 21 and the fibrous web is subsequently transferred from the first transfer belt 92 to the surface of the large drying cylinder 211 at a transfer point 214. For further stabilization of the fibrous web on the surface of the large drying cylinder 211, the first transfer belt 92' wraps around the large drying cylinder 211 at a wrap angle 219 of less than or equal to 90°.
In this variant, an optional arrangement of a drying hood 212 on the large drying cylinder 210 is conceivable.

In the 4 In the third alternative embodiment 92" contained in the invention, the fibrous web is deflected by the second suction guide roller 98, which is also wrapped around by the first transfer belt 92, to the large drying cylinder 211 of the first drying section 21, and the fibrous web is subsequently transferred from the first transfer belt 92 to the surface of the large drying cylinder 211 at a transfer point 214. For further stabilization of the fibrous web on the surface of the large drying cylinder 211, the first transfer belt 92'' wraps around the large drying cylinder 211 at a wrap angle 219 of less than or equal to 200°.

Other alternative embodiments not shown may consist of a combination of the 1 shown transfer section 90, with the removal device 227 of the 2 or 3 be formed.

Other alternative embodiments not shown may consist of a combination of the 2 shown transfer section 90, with the removal device 227 of the 1 or 3 be formed.

Other alternative embodiments not shown may consist of a combination of the 3 shown transfer section 90, with the removal device 227 of the 1 or 2 be formed.

Other alternative embodiments not shown may consist of a combination of the 4 shown transfer section 90, with the removal device 227 of the 2 or 3 be formed.

List of reference symbols

10

machine

12

Wire section

14

Press section

16

Dry section

21

first drying section

211

large drying cylinder

212

Drying hood, hot air drying hood

214

Transfer point between 90 and 21; and starting point of the first drying section of the fibrous web

215

End point of the drying section of the fibrous web on the top side

216

Safety distance between 215 and 217

217

Transfer point between 21 to 22

218

Removal scraper on the large drying cylinder

219

Wrap angle of first transfer belt around the large drying cylinder

22

first, single-row drying cylinder drying section

220

first drying sieve

221

first drying cylinder

222

second drying cylinder

223

last drying cylinder

224

Railway stabilizer

222

Deflection suction roll

227

Removal device, preferably suction guide roller or web suction box

228

Suction box

40

lower covering

50

Steam blow box

51

first press nip

52

second press nip

53

last press nip, shoe press nip

54

Shoe press roll

55

central press roller

56

Counter roller

57

Counter roller

58

Counter roller

59

Deflection roller

60

Forming screen

61

upper press felt, first press nip

62

lower press felt, first press nip

63

upper press felt, last press nip

90

Transfer section

91

Transfer section of the fibrous web

92

first transfer belt

92'

alternative guidance of the first transfer belt with wrapping

92''

alternative guidance of the first transfer belt with wrapping

93

second transfer belt

94

Support roller

95

Stabilizer, preferably transfer foil

96

Stabilizer, preferably suction box

97

first suction guide roller

98

second suction guide roller

98`

additional suction guide roller

99

Impingement dryer, steam blow box

L

Machine or web direction

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• DE 1020201112256 A1 [0004]
• DE 102021114994 A1 [0004]
• DE 102017118218 A1 [0005]
• DE 102019127104 A1 [0006]
• DE 1020161232203 A1 [0061]

Claims (17)

Machine (10) for producing or treating a fibrous web, in particular a paper or cardboard web, preferably a corrugated cardboard base paper web, comprising a wire section (12) and a press section (14) and a drying section (16), wherein a transfer section (90) is included between the press section (14) and the drying section (16), and wherein the drying section (16) comprises, immediately following the press section (14) and the transfer section (90), at least one first drying section (21) and subsequently at least one first single-row drying cylinder drying section (22), and wherein the transfer section (90) comprises at least one transfer belt (92, 93), arranged such that the fibrous web is transferred to the first drying section (21) at a first transfer point (214), and wherein the first single-row drying cylinder drying section (22) comprises at least one first drying wire (220) and a removal device (227) wrapped around the first drying wire (220), arranged such that the fibrous web is taken over from the first drying section (21) at a second transfer point (217), characterized in that the first drying section (21) comprises a large drying cylinder (211) and that the transfer section (90) forms a transfer section (91) and the at least one transfer belt (92, 93) is designed to be permeable to air. Machine after Claim 1 , characterized in that the large drying cylinder (211) has a diameter greater than 3.5 m, preferably greater than 4.5 m, in particular less than or equal to 6.5 m. Machine after Claim 1 or 2 , characterized in that the large drying cylinder (211) is minimized from wrapping around a drying screen and/or the transfer belt (92, 93) and comprises at least one drying hood (212). Machine after Claim 1 or 2 , characterized in that the large drying cylinder (211) is wrapped by a first transfer belt (92`, 92") and the wrap angle (219) is less than or equal to 200°, preferably less than 90°, in particular less than 45°. Machine according to one of the preceding claims, characterized in that the removal device (227) of the first drying cylinder drying section (22) is arranged such that the fibrous web is removed directly from a surface of the large drying cylinder (211) at the second transfer point (217). Machine according to one of the preceding claims, characterized in that the removal device (227) is a suction guide roller (227) or a web stabilizer (224), preferably a web suction box (224). Machine according to one of the preceding claims, characterized in that at least one suction box (228) wrapped around the first drying screen (220) is arranged directly before and/or after the removal device (227). Machine according to one of the preceding claims, characterized in that a safety distance (216) of greater than or equal to 0.3 m and less than or equal to 1.0 m, preferably between greater than or equal to 0.7 m and less than or equal to 0.8 m, is provided before the second transfer point (217) and after one end of the drying hood (215) in the first drying section (21). Machine according to one of the preceding claims, characterized in that the transfer section (90) comprises a first transfer belt (92) and a first suction guide roller (97) and at least one, preferably two to five, support roller(s) (94) and/or at least one, preferably two to six, stabilizer(s) (95, 96) and that the first transfer belt (92) wraps around the first suction guide roller (97) and the at least one support roller (94) and/or the at least one stabilizer (95, 96). Machine according to one of the preceding claims, characterized in that the transfer section (90) comprises a second suction guide roller (98) around which the first transfer belt (92) wraps, arranged such that the fibrous web is transferred from the first transfer belt (92) to the first drying section (21) at a transfer point (215), and that the transfer section (90) forms a hanging transfer section (91) or a twin-wire transfer section (91). Machine according to one of the preceding claims, characterized in that the transfer section (90) comprises a second transfer belt (93) arranged such that the transfer section (90) forms a twin-wire transfer section (91). Machine after Claim 10 or 11 , characterized in that the double-screen Transfer section (91) is arranged such that it is concavely curved downwards and that the first transfer belt (92) is guided above the fibrous web and the second transfer belt (93) is guided below the fibrous web. Machine according to one of the Claims 8 until 11 , characterized in that the transfer section (90), in particular the twin-wire transfer section (91), comprises exactly one stabilizer (95) which is designed as a transfer foil (95). Machine according to one of the Claims 1 until 8th , characterized in that the transfer section (90) comprises a second suction guide roller (98) around which a second transfer belt (93) is wrapped, arranged such that the fibrous web is transferred from the second transfer belt (93) to the first drying section (21) at a transfer point (215), and that the transfer section (90) comprises a horizontal transfer section (91). Machine according to one of the preceding claims, characterized in that the transfer section (90) comprises at least one impingement dryer (99) and/or steam blower box (99), arranged such that the fibrous web is additionally dried or heated in the transfer region (91) supported by the first transfer belt (92). Method for producing or treating a fibrous web, in particular a paper or cardboard web, preferably a corrugated cardboard base paper web, in a machine (10), in particular according to Claim 1 , characterized in that the fibrous web is guided from the press section (14) over a transfer section (90), and that the fibrous web is guided on a surface of a large drying cylinder (211) in a first drying section (21), and that its underside is dried by the surface of the large drying cylinder (211) and its upper side is dried by at least one drying hood (212), and that the fibrous web is taken over at a second transfer point (217) by a take-off device (227) included in the subsequent first, single-row drying cylinder drying section (22). Procedure according to Claim 16 , characterized in that the fibrous web is taken over at a temperature of greater than or equal to 60°C and less than or equal to 70°C, preferably greater than or equal to 65° and less than or equal to 70°C, at the second transfer point (217), so that the subsequent first, single-row drying cylinder drying section (21) is operated from the first drying cylinder (221) at an optimum operating point, preferably the main evaporation zone.

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