Machine and method for producing fibrous web

Abstract

The invention relates to a machine and a method for producing a fibrous web, in which the fibrous web (1) is guided through a dewatering roller (5) between a transfer region (3) and a drying region (6). The invention is characterized in that a nip (10) is formed in the winding region (7) of the dewatering roller (5) and the nip (10) is arranged in the outlet region of the suction region (11) of the dewatering roller (5) or behind the suction region (11), the drying medium being sucked into the suction region (11) through the fibrous web (1) before the nip (10). The invention allows energy-efficient production of high-quality fibrous webs (1).

Description

Technical Field

[0001] This invention relates to a method for manufacturing fiber webs, particularly structured thin paper webs, the method comprising the following steps: Fiber webs are formed from the fiber suspension and transferred from the first shaped mesh to the structural mesh within the transfer region. The fiber web on the structural mesh is further guided from the transfer area by dewatering rollers (especially suction rollers) through at least one drying zone designed for hot air penetration drying. In this invention, a fiber web is guided through a dewatering roller between a structural mesh and a dewatering mesh (especially felt) within the winding area of ​​the dewatering roller, and is at least partially wound around the dewatering roller. The suction area of ​​the dewatering roller is at least partially surrounded by the winding area, and the fiber web is dewatered through the suction area. The invention also relates to a machine for manufacturing fiber webs. Background Technology

[0002] To manufacture high-quality fiber webs, particularly structured fiber webs, explicit mechanical dehydration via extrusion is eliminated. Those skilled in the art know of hot air through-drying methods, in which the fiber web is formed in a forming area, transferred to a structural mesh, and dried primarily by applying vacuum and heat drying, especially hot air through-drying. Fiber webs manufactured in this manner include structured hot air through-drying tissues for use as kitchen paper, toilet paper, or similar products. High-quality fiber webs are characterized by greater thickness and therefore larger volume, resulting in higher absorbency, absorption rate, and softness compared to conventionally extruded fiber webs.

[0003] Therefore, EP3359733A1 discloses a method for manufacturing fiber webs, particularly tissue paper or toilet paper, wherein a pre-dehydration device is provided before the TAD dryer. Specifically, EP3359733A1 teaches that pre-dehydration must be performed gently to avoid reducing the quality of the fiber web, wherein using a press for pre-dehydration would excessively compress the fiber web and could adversely affect its quality. Summary of the Invention

[0004] The technical problem to be solved by this invention is to provide a method or machine for producing high-quality fiber webs with particularly high efficiency. This method should in particular allow for the production of fiber webs that maintain high quality with reduced energy consumption, namely, those with higher paper thickness or volume, higher absorbency, higher absorption speed, and improved softness.

[0005] According to the invention, this technical problem is solved by the following method: the winding region includes a pressing zone formed between the dewatering roller and the mating roller; the fiber web is mechanically dewatered in the pressing zone by extrusion, and the pressing zone is arranged in the outlet region of the suction zone or after the suction zone, wherein, before the pressing zone, in the winding region, the drying medium (especially hot air and / or steam) is drawn from the drying hood through the fiber web into the suction zone of the dewatering roller. Thus, the fiber web is formed in the forming region, particularly by dewatering the fiber suspension introduced from the headbox between the first forming net and the second forming net. The fiber web is transferred from the first forming net to the structural net in the transfer region. A structured drying screen, and especially a TAD (hot air through-drying) screen, is suitable as the structural net. Preferably, the transfer takes place in the transfer region such that the fiber web is transferred from the faster-running forming net to the slower-running structural net, and the forming net preferably runs 2% faster than the structural net, particularly preferably 10% faster. The advantage of transferring from a faster-running forming net to a slower-running structural net is that it improves the quality properties of the fiber web during transfer, particularly its thickness and therefore its volume, as well as its water absorption or its absorption rate and its softness. After the transfer zone, the fiber web is further guided on the structural net by dewatering rollers (especially suction rollers) through a drying zone designed for hot air penetration drying. For example, the fiber web may have already been wound onto a roll after the drying zone. In another embodiment of the method of the invention, the fiber web is transferred from the structural net to a drying drum (especially a Yankee cylinder) after the drying zone and dried, wherein, after drying and possible wrinkling (i.e., scraping the fiber web directly from the surface of the drying drum with a scraper), the fiber web can be wound into a roll. The Yankee cylinder is a drying drum and is characterized by a diameter greater than 3 m, wherein the fiber web is guided directly on the surface of the Yankee cylinder. Optionally, a drying hood can be provided for the drying drum, through which hot air and / or steam are directly directed to the fiber web guided on the drying drum. For example, this drying hood can be constructed as an impingement airflow drying hood.

[0006] After the transfer zone and before the drying zone, the fiber web is guided on the structural mesh through dewatering rollers, particularly suction rollers. Here, the fiber web is at least partially wound around the dewatering roller, wherein the fiber web is guided through the winding zone of the dewatering roller, and within the winding zone, the fiber web is guided through the dewatering roller between the structural mesh and the dewatering mesh (especially felt). In particular, the dewatering mesh is guided between the fiber web and the dewatering roller. The winding zone at least partially includes the suction zone of the dewatering roller, which allows the fiber web to be dewatered by applying a vacuum to the suction zone. When using felt, a vacuum of 300 mbar to 500 mbar has proven particularly suitable. According to the invention, the winding zone includes a pressure zone formed between the dewatering roller and the mating roller, wherein the fiber web is mechanically dewatered by compression within the pressure zone, and the pressure zone is arranged within the exit zone of the suction zone or after the suction zone. Importantly, before the pressing zone (where "before" refers to the movement of the fiber web), the drying medium (especially hot air and / or steam) is drawn from the drying hood through the fiber web into the suction zone of the dewatering roller within the winding area, thus promoting dewatering of the fiber web. Surprisingly, as the fiber web is guided around the dewatering roller between the structural and dewatering webs, dewatering pressure is applied from the structural web to the fiber web due to the tension of the externally guided web (i.e., the structural web) relative to the internal dewatering roller, whereby water dewatered from the fiber web is advantageously absorbed by the capillary-acting dewatering web (especially felt). The dewatering effect of the fiber web is further improved by the suction of the internal web (i.e., the dewatering web resting against the dewatering roller) through the suction zone of the dewatering roller. Furthermore, by guiding the drying medium (especially hot air and / or steam) from the drying hood onto an externally guided mesh (i.e., a structural mesh, such as a drying mesh and especially a TAD screen), which has advantageous porosity and air permeability, the dehydration of the fiber web can be further improved. Here, the apparatus of the present invention has a synergistic effect, achieving a significant increase in the dryness of the fiber web before the drying zone with relatively low cost inputs (vacuum, drying medium, pressure zone), while maintaining the quality performance parameters of the fiber web. Therefore, for example, when a linear load of 50 kN / m is applied in the pressure zone, the dryness of the fiber web can be increased by up to 5%, i.e., from 25% to 30%, which means a reduction in the thermal drying cost input in the drying zone by up to 20%. Thus, simultaneously performing these method steps—guiding the fiber web between a dehydrating mesh that particularly acts as a capillary and a permeable structural mesh, dehydrating by tension of the structural mesh, applying the drying medium through the permeable structural mesh, and applying a vacuum to the dehydrating mesh that particularly acts as a capillary—results in a positive effect within the pressure zone. What is particularly surprising here is that the fiber web, which is thus “pre-dehydrated” before the pressing zone, can be guided through the pressing zone in a manner that does not impair the quality of the fiber web, wherein the pressing zone is arranged in the winding area between the dewatering roller and the mating roller.In the apparatus according to the invention, the fiber web is protected by the structure of the structural mesh within the pressing zone, and especially due to the "pre-dehydration" according to the invention, the fiber web has sufficiently low moisture content, i.e., sufficiently high dryness, before the pressing zone. Therefore, it is understood that when the fiber web is correspondingly "pre-dehydrated" before the pressing zone, the pressing zone has essentially no negative effect on the quality characteristics of the fiber web. In particular, this advantageous effect is observed for fiber webs with a basis weight between 14 and 35 g / m² on the structural mesh.

[0007] In an advantageous configuration of the method according to the invention, the initial mechanical dewatering is performed between the transfer zone and the drying zone by squeezing the fiber web within a compression zone. This initial mechanical dewatering, achieved by squeezing the fiber web within a compression zone, is performed either in the outlet region of the suction zone or after the suction zone, wherein the fiber web is first guided around the dewatering roller in the winding region between the structural mesh and the dewatering mesh, and then dewatered in the suction zone of the dewatering roller and further through the drying medium of the drying hood. In particular, if the compression zone is located in the inlet region of the suction zone, it has an adverse effect on the quality performance parameters of the fiber web. Particularly preferably, the squeezing is performed with a linear load greater than 30 kN / m, preferably greater than 40 kN / m, and especially preferably greater than 45 kN / m. This allows for significant dewatering by squeezing. With lower linear loads, there is essentially no improvement in dryness, i.e., no mechanical dewatering by squeezing.

[0008] In another advantageous configuration of the method according to the invention, mechanical dehydration is carried out by extrusion with a linear load of up to 100 kN / m, preferably up to 80 kN / m, and particularly preferably up to 55 kN / m. Advantageously, as the linear load increases, the mechanical dehydration by extruding the fiber web is increased. To ensure that the quality performance parameters of the fiber web are not negatively affected, the linear load is correspondingly limited to up to 100 kN / m, preferably up to 80 kN / m, and particularly preferably up to 55 kN / m.

[0009] In a similarly advantageous configuration of the method according to the invention, the fiber web is dehydrated through an absorption zone, the dehydration time of which corresponds to a length of at least 0.8 m, preferably at least 1.3 m, and particularly preferably at least 1.7 m of the absorption zone. It is understood that the corresponding residence time of the fiber web in the absorption zone provides advantageous dehydration via a suction zone, wherein this residence time corresponds to a length of at least 0.8 m, preferably at least 1.3 m, and particularly preferably at least 1.7 m of the suction zone. Particularly advantageously, the drying medium is drawn through the fiber web into the suction zone within the winding region, wherein the drying medium is applied over a drying length of at least 0.95 m, and particularly preferably at least 1.35 m. This allows the fiber web to be advantageously dehydrated before the pressing zone, thereby particularly ensuring that the quality properties of the fiber web do not deteriorate within the pressing zone.

[0010] In another advantageous configuration of the method according to the invention, the fiber web is dehydrated to a dryness of at least 20%, preferably 23%, and particularly preferably 26% before passing through the pressing zone. This allows for ensuring that the quality properties of the fiber web do not deteriorate within the pressing zone.

[0011] In an equally advantageous configuration of the method according to the invention, hot air penetration drying of the fiber web is carried out in the drying zone at a temperature above 120°C, and particularly preferably above 180°C. It is also preferred that the hot air penetration drying is carried out at a temperature below 250°C, and particularly below 220°C. This allows for a high drying rate, i.e., a high drying speed, wherein the structural mesh (e.g., a drying screen and especially a TAD screen) can typically withstand such temperatures for extended periods. Typically, the fiber web is guided through at least one hot air transmission cylinder for hot air penetration drying, wherein the structural mesh is preferably guided between the fiber web and the hot air transmission cylinder, and a transmission flow medium (e.g., hot air and / or steam) is applied to the fiber web for hot air penetration drying, and the transmission flow medium is drawn into the hot air transmission cylinder through the structural mesh. In particular, exhaust medium from the machine section following the drying section is used for hot air penetration drying. Thus, exhaust air from a subsequent drying hood (e.g., corresponding to a Yankee cylinder) can be at least partially used for hot air penetration drying.

[0012] The present invention also relates to a machine for manufacturing fiber webs (particularly structured thin paper webs). The machine includes: The forming area used to form fiber webs from fiber suspension, and The transfer area used to transfer the fiber web from the first shaped mesh to the structural mesh. A dewatering roller, particularly a suction roller, includes a suction zone with an outlet area, wherein the fiber web is guided within the winding area of ​​the dewatering roller between a structural mesh and a dewatering mesh (partially felt) in a manner that at least partially winds around the dewatering roller, and the suction zone is at least partially surrounded by the winding area. A drying zone for hot air penetration drying of fiber webs. Here, the fiber webs are guided from the transfer zone through the dewatering rollers on the structural mesh through the drying zone. According to the invention, a pressure zone is formed in the winding zone between the dewatering rollers and the mating rollers for mechanical dewatering of the fiber webs guided between the structural mesh and the dewatering mesh. The pressure zone is arranged in the exit zone of the suction zone or after the suction zone, wherein a drying hood is correspondingly provided for the dewatering rollers in the winding zone before the pressure zone, and the drying medium (especially hot air and / or steam) can be guided or drawn from the drying hood through the fiber webs into the suction zone of the dewatering rollers. The design of the machine according to the invention allows the execution of the method according to the invention and thus achieves the aforementioned advantageous effects, wherein the dryness of the fiber webs before the drying zone can be significantly increased with relatively low inputs (vacuum, drying medium, pressure zone) while maintaining the quality performance parameters of the fiber webs.

[0013] In a particularly advantageous embodiment of the machine according to the invention, the initial mechanical dehydration is achieved by squeezing the fiber web within a pressure zone between the transfer zone and the drying zone. Thus, mechanical dehydration is only performed by squeezing the fiber web after it has been guided between the structural and dehydrating nets through the suction zone of the dehydrating rollers, i.e., after the drying medium has been drawn from the drying hood through the fiber web. Therefore, the “pre-dehydrated” fiber web can proceed through the subsequent pressure zone, where mechanical dehydration by squeezing does not have a detrimental effect on the quality characteristics of the fiber web. Particularly advantageously, to achieve significant dehydration of the fiber web within the pressure zone, the pressure zone is designed to have a linear load greater than 30 kN / m, preferably greater than 40 kN / m, and especially preferably greater than 45 kN / m.

[0014] In another advantageous configuration of the machine according to the invention, the outlet region occupies at most 30%, preferably at most 20%, and particularly preferably 15% of the length of the suction zone of the dewatering roller. Particularly advantageously, the length of the suction zone is at least 0.8 m, preferably at least 1.3 m, and particularly preferably at least 1.7 m. Dewatering the fiber web by means of dewatering before the pressing zone, followed by dewatering by extrusion, does not have a detrimental effect on the quality characteristics of the fiber web.

[0015] In an equally advantageous design of the machine according to the invention, the fiber web is guided through at least one hot air transmission cylinder in the drying zone for hot air penetration drying, and a structural mesh is arranged between the fiber web and the hot air transmission cylinder. Here, hot air penetration drying is performed by applying a transmission flow medium—e.g., hot air and / or steam—to the fiber web and drawing the transmission flow medium into the hot air transmission cylinder through the structural mesh. This ensures, on the one hand, that the fiber web is well secured to the structural mesh, and on the other hand, that the structural mesh does not come into direct contact with the transmission flow medium—e.g., hot air and / or steam. Particularly preferably, exhaust medium from the machine section behind the drying section is used as the transmission flow medium. In particular, exhaust air from a subsequent drying hood corresponding to the Yankee dryer can be at least partially used as the transmission flow medium.

[0016] In another advantageous configuration of the machine according to the invention, the mating rollers are designed, in particular, as smoothing rollers or shoe rollers. Specifically, the use of smoothing rollers allows for the avoidance of marking the fiber web within the pressing zone, wherein the smoothing rollers preferably have a rubber or PU coating. The use of a PU coating with a hardness of 30 P&J has proven particularly advantageous. Using shoe rollers as mating rollers allows the pressing zone to be designed as a long pressing zone, thereby improving the structuring of the fiber web by pressing or squeezing it longer into the structural mesh on the dewatering blanket. Furthermore, long pressing zones are characterized by advantageous dewatering and reduced rewetting, wherein (typical for long pressing zones) the lower maximum pressing pressure within the pressing zone allows the structured fiber web to subsequently separate better from the structural mesh. Attached Figure Description

[0017] The invention will now be described exemplarily with reference to the accompanying drawings.

[0018] Figure 1 The machine according to the present invention is shown.

[0019] Figure 2 A dewatering roller according to the invention is shown between the transfer zone and the drying zone. Detailed Implementation

[0020] Figure 1A machine according to the invention is shown, in which a fiber web 1, particularly a structured thin paper web, is manufactured. The fiber web 1 is formed in a forming zone 13 by a fiber suspension between a first forming mesh 2 and a second forming mesh. In a transfer zone 3, the fiber web is transferred from the first forming mesh 2 to a structured mesh 4, such as a structured drying screen, and particularly a TAD (hot air through-drying) screen. Preferably, the fiber web 1 is transferred from the faster-running forming mesh 2 to the slower-running structured mesh 4, wherein the forming mesh 2 preferably runs at least 2% faster than the structured mesh 4, and particularly preferably at least 10% faster. The fiber web 1 is further guided from the transfer zone 3 on the structured mesh 4 by dewatering rollers 5 (especially suction rollers) through at least one drying zone 6 designed for hot air through-drying. In the drying zone 6, the fiber web 1 is guided through at least one hot air through-cylinder 15, wherein the structured mesh 4 is preferably arranged between the fiber web 1 and the hot air through-cylinder 15. The hot air penetration drying of the fiber web 1 is preferably carried out at a temperature above 120°C, and particularly preferably above 180°C. Optionally, after drying zone 6, the fiber web 1 can be transferred from the structural mesh 4 to the drying drum 14 (especially a Yankee cylinder) for further drying, wherein after further drying and possible wrinkling of the fiber web 1 (i.e., scraping the fiber web 1 directly from the surface of the drying drum 14 with a scraper), the fiber web 1 can be wound into a roll. Within the winding zone 7 of the dewatering roller 5, the fiber web 1 is guided through the dewatering roller 5 between the structural mesh 4 and the dewatering mesh 8 (especially felt), wherein the dewatering mesh 8 is guided between the fiber web 1 and the dewatering roller 5. The fiber web 1 is at least partially wound around the dewatering roller 5, and the winding zone 7 includes a pressure zone 10 formed between the dewatering roller 5 and the mating roller 9 to mechanically dewater the fiber web 1 by compression. Here, the mating roller 9 is, for example, especially a smoothing roller or a shoe roller. Within the winding zone 7, a drying hood 12 is arranged in front of the pressure zone 10 to apply a drying medium, particularly hot air and / or steam.

[0021] Figure 2A dewatering roller according to the invention is shown located between the transfer zone and the drying zone. Here, fiber web 1 is transferred from the forming mesh 2 to the structural mesh 4 within the transfer zone 3, and further supplied by the dewatering roller 5 on the structural mesh 4 to the drying zone 6, which is designed for hot air penetration drying. The dewatering roller 5 is particularly designed as a suction roller, wherein, within the winding zone 7 of the dewatering roller 5, fiber web 1 is guided on the dewatering roller 5 between the structural mesh 4 and the dewatering mesh 8 (especially felt), while the dewatering mesh 8 is guided between the fiber web 1 and the dewatering roller 5. Fiber web 1 is at least partially wound around the dewatering roller 5. The suction zone 11 of the dewatering roller 5 is at least partially surrounded by the winding zone 7, and dewatering of fiber web 1 is achieved. According to the invention, the winding zone 7 includes a pressure zone 10 formed between the dewatering roller 5 and the mating roller 9, wherein fiber web 1 is mechanically dewatered by compression within the pressure zone 10, and the pressure zone 10 is arranged in the outlet region of the suction zone 11. Here, the outlet area includes, for example, a maximum of 30%, preferably a maximum of 20%, and particularly preferably a maximum of 15% of the length of the suction zone 11 of the dewatering roller 5. Alternatively, the pressing zone 10 may also be arranged after the suction zone 11.

[0022] Preferably, the initial mechanical dehydration is performed between the transfer zone 3 and the drying zone 6 by squeezing the fiber web 1 within the pressure zone 10, wherein mechanical dehydration is performed by squeezing within the pressure zone 10 with a linear load greater than 30 kN / m, preferably greater than 40 kN / m, and particularly preferably greater than 45 kN / m. Particularly advantageous dehydration by the suction zone 11 of the dehydration roller 5 is achieved over a length of at least 0.8 m, preferably at least 1.3 m, and particularly preferably at least 1.7 m. According to the invention, within the winding zone 7, the drying medium (especially hot air and / or steam) is drawn from the drying hood 12 through the fiber web 1 into the suction zone 11 of the dehydration roller 5 before the pressure zone 10.

[0023] This invention offers numerous advantages. Surprisingly, the dryness of the fiber web is significantly improved prior to the drying zone, while maintaining the fiber web's quality performance parameters. Here, the fiber web is protected by the structure of the structural mesh within the pressing zone, wherein, particularly through the "pre-dehydration" of the fiber web according to the invention, it possesses sufficiently low humidity or sufficiently high dryness, so that the pressing zone does not negatively affect the quality performance characteristics of the fiber web.

[0024] List of reference numerals 1. Fiber width 2. Molded mesh blanket 3. Transfer Area 4. Structural mesh 5 Dewatering rollers 6. Dry Area 7. Winding area 8. Dehydrated mesh blanket 9 Paired Rollers 10 pressure zone 11 Suction Zone 12 Drying hood 13 Molding Area 14 Drying drum 15. Hot air transmission cylinder.

Claims

1. A method for manufacturing fiber webs (1), particularly structured thin paper webs, the method comprising the following steps: The fiber web (1) is formed from the fiber suspension and transferred from the first shaped mesh (2) to the structural mesh (4) within the transfer area (3). The fiber web (1) is further guided on the structural mesh (4) from the transfer area (3) by dewatering rollers (5), especially suction rollers, through at least one drying area (6) designed for hot air penetration drying. In this process, the fiber web (1) is guided through the dewatering roller (5) between the structural mesh (4) and the dewatering mesh (8), particularly the felt, within the winding area (7) of the dewatering roller (5), and is at least partially wound around the dewatering roller (5). The suction area (11) of the dewatering roller (5) is at least partially surrounded by the winding area (7), and the fiber web (1) is dewatered through the suction area (11). The winding area (7) comprises sections formed on the dewatering roller. (5) and the pressing zone (10) between the pairing rollers (9), the fiber web (1) is mechanically dehydrated by extrusion in the pressing zone (10), and the pressing zone (10) is arranged in the outlet area of ​​the suction zone (11) or after the suction zone (11), wherein the drying medium, especially hot air and / or steam, is drawn from the drying hood (12) through the fiber web (1) into the suction zone (11) of the dehydration roller (5) in the winding area (7) before the pressing zone (10).

2. The method according to claim 1, wherein, Mechanical dehydration is first performed between the transfer zone (3) and the drying zone (6) by squeezing the fiber web (1) within the compression zone (10).

3. The method according to claim 1 or 2, wherein, Mechanical dehydration is achieved by extrusion under a linear load greater than 30 kN / m, preferably greater than 40 kN / m, and especially preferably greater than 45 kN / m.

4. The method according to any one of claims 1 to 3, wherein, Mechanical dehydration is achieved by extrusion with a linear load of up to 100 kN / m, preferably up to 80 kN / m, and especially preferably up to 55 kN / m.

5. The method according to any one of claims 1 to 4, wherein, The fiber width (1) is dehydrated through the absorption zone (11) for a time length corresponding to at least 0.8 m of the length of the absorption zone (11), preferably at least 1.3 m, and particularly preferably at least 1.7 m.

6. The method according to any one of claims 1 to 5, wherein, The fiber web (1) is dehydrated to a dryness of at least 20%, preferably at least 23%, and particularly preferably at least 26% before passing through the compression zone (10).

7. The method according to any one of claims 1 to 6, wherein, Within the transfer area (3), the fiber web (1) is transferred from the faster-running shaped web (2) to the slower-running structural web (4), and the shaped web (2) runs at more than 2% faster than the structural web (4), and especially preferably more than 10% faster.

8. The method according to any one of claims 1 to 7, wherein, The fiber web (1) is subjected to hot air penetration drying at a temperature above 120°C, and especially preferably above 180°C, within the drying zone (6).

9. A machine for manufacturing fiber webs (1), particularly for manufacturing structured thin paper webs, said machine for manufacturing fiber webs (1) comprising: - Forming region (13), the forming region being used to form fiber webs (1) from fiber suspension. and - Transfer area (3), the transfer area is used to transfer the fiber web (1) from the first shaped mesh (2) to the structural mesh (4). - A dewatering roller (5), particularly a suction roller, the dewatering roller (5) including a suction zone (11) with an outlet area, wherein the fiber web (1) is guided within the winding area (7) of the dewatering roller (5) between the structural mesh (4) and the dewatering mesh (8), particularly felt, in such a way as to at least partially wind around the dewatering roller (5), and the suction zone (11) is at least partially surrounded by the winding area (7). - Drying zone (6), the drying zone being used for hot air penetration drying of the fiber web (1), wherein the fiber web (1) on the structural mesh (4) can be guided from the transfer zone (3) through the dewatering roller (5) through the drying zone (6), characterized in that a pressing zone (10) is formed in the winding zone (7) between the dewatering roller (5) and the mating roller (9) for mechanical dewatering of the fiber web (1) guided between the structural mesh (4) and the dewatering mesh (8), and the pressing zone (10) is arranged in the outlet area of ​​the suction zone (11) or after the suction zone (11), wherein before the pressing zone (10), a drying hood (12) is correspondingly provided for the dewatering roller (5) in the winding zone (7), and the drying medium, especially hot air and / or steam, can be drawn from the drying hood (12) through the fiber web (1) into the suction zone (11) of the dewatering roller (5).

10. The machine according to claim 9, wherein, Mechanical dehydration is first performed between the transfer zone (3) and the drying zone (6) by squeezing the fiber web (1) within the compression zone (10).

11. The machine according to claim 9 or 10, wherein, The pressure zone (10) between the dewatering roller (5) and the paired roller (9) is configured to compress the fiber web (1) with a linear load greater than 30 kN / m, preferably greater than 40 kN / m, and especially preferably greater than 45 kN / m.

12. The machine according to any one of claims 9 to 11, wherein, The outlet area comprises up to 30%, preferably up to 20%, and particularly preferably up to 15% of the length of the suction zone (11) of the dewatering roller (5).

13. The machine according to any one of claims 9 to 12, wherein, The length of the suction zone (11) is at least 0.8m, preferably at least 1.3m, and especially preferably at least 1.7m.

14. The machine according to any one of claims 9 to 13, wherein, Within the drying zone (6), the fiber web (1) is guided through at least one hot air transmission cylinder (15) for hot air penetration drying, and the structural mesh (4) is always arranged between the fiber web (1) and the hot air transmission cylinder (15).

15. The machine according to any one of claims 9 to 14, wherein, The paired rollers (9) are in particular smoothing rollers or shoe rollers.

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