DE102010041608A1 - Double wire forming device for fibrous web producing machine, has guide roll that is designed as press roll such that dehydrating pressure is generated between two wire portions by applied tension - Google Patents

Abstract

The device has wire portions (4,5) that are fed over peripheral regions (7,9) of deflecting elements (6,8). The wedge shaped gap (10) is formed between wire portions to receive fibrous material suspension (3) from head box (11). The wire portions are fed into twin-wire section (12) and guided over circumferential region (16) of guide roller (15). The two wire portions are separated by separation roller (17). The guide roll is designed as press roll such that the dehydrating pressure is generated between two wire portions by the applied tension.

Description

The invention relates to a twin-wire former for a machine for producing a fibrous web, in particular a paper, cardboard or packaging paper web, from at least one pulp suspension, with two endless screens, each forming a wire loop, of which the first wire is guided over a peripheral region of a first deflecting element and the second sieve is guided over a peripheral region of a second deflecting element, the two sieves forming a wedge-shaped material inlet gap, which receives at least one fibrous suspension directly from a headbox, in the region of the first deflecting element of the one sieve or after the expiration of the two sieves converge from the respective deflecting and then form a Doppelsiebstrecke in which the two wires are first passed over forming and / or dewatering elements and in the end region of the two wires are guided over a peripheral region of a guide roll, where in indirectly or immediately after the guide roller - seen in the direction of wire direction - at least one separating device, in particular a separating sucker or a separation roller for separating the one sieve from the other sieve with the fibrous web lying thereon and to be produced is arranged.

Such a twin-wire former is known from a large number of publications, for example also from the document DE 201 04 380 U1 ,

A twin-wire former of this type is usually equipped with a sieve suction roll for increasing the dry content after the formation of the fibrous web to be produced. This requires a strong vacuum and a high volume of air during operation of the twin-wire former. The generation of the vacuum by means of a blower or a vacuum pump is very energy-intensive and therefore also expensive. In addition, this generation of vacuum results in ongoing production costs for the operator. Moreover, the investment and maintenance costs for a sieve suction roll and a vacuum system are relatively high. An ordinary suction sieve can certainly cost more than 500 thousand euros.

One hitherto remedy for these high costs has been to realize an adapted vacuum level at the wire suction roll or to eliminate the wire suction roll due to the incorporation of at least one more efficient high vacuum sucker. However, it has been found that remedial measures and improvements have only partially been achieved through these remedies, as vacuum has been applied to ensure good and efficient drainage. And the friction of the fabric, in particular of the forming fabric on the tread of the high vacuum suction requires a non-negligible drive energy and also causes a high string wear.

It is therefore an object of the invention to improve a twin-wire former of the type mentioned in such a way that the aforementioned disadvantages of the prior art as far as possible, preferably completely eliminated. In particular, an increase in the previous dry content in the fibrous web to be produced is to be made possible with a significantly lower energy input. In addition, the acquisition and operating costs of the mechanical equipment should be reduced as possible.

This object is achieved in a twin-wire former of the type mentioned in the present invention, that the guide roller is formed as a Siebzug-press roller, the dewatering pressure is generated on the produced between the two wires fibrous web by the applied wire tension.

The object of the invention is completely solved in this way.

The inventive design of the guide roller as a Siebzug-press roller, the dewatering pressure is generated on the produced between the two fabrics fibrous web by the applied wire tension, allows an increase of the previous dry content in the produced fibrous web with a significantly lower energy consumption. From a process-essential point of view, it is important that at least the sieve facing away from the guide roll has the necessary wire tension. Of course, the screen facing the guide roller may have a screen tension, which in turn may be different from the other screen tension, which is subject to the screen facing away from the screen.

This drainage principle according to the invention is also energy-saving and it can also be a higher dewatering pressure due to the applied wire tension than in a known vacuum dewatering can be achieved. Furthermore, it is advantageous that the dewatering pressure acts on both sides of the fibrous web to be produced and that the acquisition and operating costs of the mechanical equipment are reduced due to the elimination of the particularly expensive in operation Siebsaugwalze.

Another significant advantage lies in the fact that the dewatering principle according to the invention can be easily implemented both in new plants and in the optimization of existing plants.

The guide roller formed as a wire-draw press roll preferably has a roll diameter in the range of 100 to 2,000 mm, preferably from 200 to 1,500 mm, in particular from 300 to 1,000 mm. In this case, it is generally the case that a smaller roller diameter of the guide roller designed as a wire-pull press roll increases the dewatering pressure in the fibrous web to be produced at the same wire tension according to the following formula: p = S / R, where p is the dewatering pressure [kPa], S is the wire tension [N / m], and R is the radius of the guide roll [m] formed as a wire draw press roll. For example, at a screen tension of 15 kN / m and one. Radius of the trained as Siebzug-press roller guide roller of 0.15 m, the dewatering pressure 100 kPa or 1 bar.

Furthermore, a plurality of guide devices, in particular a plurality of baffles, are preferably arranged above the guide screen designed as a wire-pull press roller and merge, collect and dissipate the spin-off water formed by the guide roller formed as a wire-pull press roller by the centrifugal force at the roller circumference.

Furthermore, at least one exhaust device, in particular an evacuated exhaust air duct, which collects and discharges the air introduced with the spin water, is preferably disposed of the sieve facing away from the guide roller as a screen-pull press roller. As a result, undesired mist formation in the region of the twin-wire former is markedly reduced, preferably even completely prevented.

Furthermore, the guide roller constructed as a wire-draw press roll preferably has a roll surface with a storage volume, so that the dewatered water drained from the fibrous web to be produced can be taken up. This possible design ideally promotes the rapid collection and easy removal of the resulting white water.

So that a process-technically sufficient storage volume without any tendency to mark is present in the fibrous web to be produced, the storage volume of the roll surface preferably includes recesses, in particular parallel radial or angled and / or parallel spiral grooves, bores or the like, and the roll surface preferably has a land area of ≥ 40 %, preferably of ≥ 50%, in particular of ≥ 60%, of the theoretical roll surface.

The depressions formed as radial grooves and forming the storage volume of the roll surface preferably have a triangular, triangular, quadrangular and / or polygonal groove cross section. In particular, the triangular groove cross section of the radial grooves preferably has at least one base groove radius, and the quadrangular groove cross section of the radial grooves preferably has parallel or angled groove walls. Thus, when a maximum storage volume is reached in the roll surface of the guide roll formed as a wire draw press roll, a maximum land area on the roll surface of the guide roll formed as a wire draw press roll can also be produced.

The roll surface may also consist of a multiplicity of rings adjacent to the roll axis, in particular steel rings or the like, or of at least one steel strip wound spirally around the roll shell, in which case the rings or the at least one steel strip have a contoured profile cross section for an optimized application or . having.

Moreover, in the region of the guide roller formed as a wire-draw press roll, preferably at least one guide roll extending parallel to the roll axis of the guide roll formed as a wire-pull press roll is arranged on the outer peripheral surface of the guide roll formed as a wire-pull press roll and arranged to roll off and support the support roll formed as Siebzug-press roller guide roller at least in sections, preferably along its entire width touched and substantially, preferably completely contributes to receiving the resulting force.

This support roller contributes significantly to a reduction in the deflection of the trained as a wire draw press roll guide roll at preferably smaller roll diameters. Also, the running properties of the two screens in this area of the twin-wire former are improved, the screen wear is reduced, the screen tension in the cross machine direction is made as uniform as possible and the quality of the conveyed and produced fibrous web is increased. Furthermore, the smaller roller diameters allowed increase the register roller effect and immediately lower the roller curvature, which has a positive effect on the uniformity of the profile of the wire tension in the cross-machine direction and thus very significantly improves the cross-sectional stability of the fibrous web to be produced. In addition, the manufacturing cost of the formed as a wire-draw press roll guide roll can be reduced and the machine for producing the fibrous web can be made wider. The resilient support of the support roller also has the advantage of being a sudden Pressure pulse, for example, caused by a carried along with the sieve pulp batches, can yield.

Such a support roller is for example in the document DE 102 59 607 A1 , the content of which is hereby made the subject of the present description.

Furthermore, the support roller is preferably designed as a deflection-supported roller. Alternatively or additionally, the support roller is provided with at least one Walzenbombierung and / or at least one drum bandage for the purpose of intermittent support designed as a wire draw press roll guide roll. The at least one roll bandage may be formed as a kind of "wear layer".

A deflection-supported roller is for example from the document DE 101 12 202 A1 The content of which is hereby made the subject of the present description.

Also, at least one scraper device is preferably provided for the purpose of conditioning the adjacent roller surface. The at least one scraper device can act on the guide roller designed as a wire-draw press roller, on the support roller and / or on another arbitrary roller.

And between the guide roller formed as a wire drawing press roller and the separating device, in particular the separating suction device or the separating roller, at least one strip is preferably arranged for the purpose of stripping the white water adhering to the running surface of the screen.

The twin-wire former according to the invention is outstandingly suitable for use in a machine for producing a fibrous web, in particular a paper, board or packaging paper web, from at least one fibrous stock suspension.

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

Show it

1 a schematic representation of a preferred embodiment of a twin-wire former according to the invention for a machine for producing a fibrous web of at least one pulp suspension;

2 schematic view of the deflection of a preferred embodiment of a twin-wire former according to the invention for a machine for producing a fibrous web of at least one pulp suspension; and

3 and 4 schematic and partial cross-sectional views of two preferred embodiments of roll surfaces of each designed as a guide roller Siebsaug-press rolls of Doppelzutiebformern invention for a machine for producing a fibrous web from at least one pulp suspension.

The 1 shows a schematic representation of a twin-wire former 1 for a machine 100 for producing a fibrous web 2 from at least one pulp suspension 3 , At the fibrous web 2 in particular, it may be a paper, board or packaging paper web.

The twin-wire former has two endless, one wire loop each 4.S . 5.S forming sieves 4 . 5 on, of which the first sieve 4 over a peripheral area 7 a first deflecting element 6 is guided and the second sieve 5 over a peripheral area 9 a second deflecting element 8th is guided. In the present embodiment, both deflection elements 6 . 8th so-called and known in the art breast rolls.

The two sieves 4 . 5 run to form a wedge-shaped Stoffseinlaufspalts 10 , the immediate of a headbox only schematically indicated 11 the at least one pulp suspension 3 receives after its expiration of the respective deflection 6 . 8th converge and then form a Doppelsiebstrecke 12 ,

The schematically indicated headbox 11 may be performed according to the prior art. So he may be a multi-layer headbox, he may be equipped with a dilution water control, he may have a lamellar headbox, which may have different fin lengths.

In an alternative embodiment known to the person skilled in the art and thus not explicitly illustrated, the two screens can also converge in the region of the first deflecting element of the one screen and subsequently form a double-wire section. In this case, the deflecting element which guides one sieve, that is to say one of the two sieves, as a rule comprises a forming roller and the deflecting element which guides the other sieve, as a rule a breast roller.

In the twin-wire zone 12 are the two sieves 4 . 5 initially above the specialist known forming and / or drainage elements 13 guided. In the end area 14 are the two sieves 4 . 5 then over a peripheral area 16 a guide roller 15 guided, wherein directly or indirectly after the guide roller 15 - seen in the wire direction R arrow - at least one separator 17 , in particular a separating sucker 17.1 to separate the one sieve 5 from the other sieve 4 with the fibrous web lying thereon and to be produced 2 is arranged.

The separation of the two sieves 4 . 5 can of course also be done in a different manner known in the art, for example by means of a defined arrangement of at least one the separation of the two wires 4 . 5 causing element, in particular of a separation roller.

It is now envisaged that the guide roller 15 as a wire draw press roll 15.1 is formed, whose drainage pressure p on the between the two sieves 4 . 5 fibrous web to be produced 2 is generated by the applied wire tension S.

In terms of process-essential aspects, it is important that at least that of the guide roller 15 remote sieve 5 has the necessary screen tension S. Of course, that can also be the guide roller 15 facing sieve 4 have a screen tension S, which in turn is different from the other screen tension S, which is that of the guide roller 15 remote sieve 4 is subject to, can be.

The as Siebzug-press roll 15.1 trained guide roller 15 has a roll diameter 15.D in the range of 100 to 2,000 mm, preferably from 200 to 1,500 mm, in particular from 300 to 1,000 mm.

Furthermore, over that of the Siebzug-press roll 15.1 trained guide roller 15 remote sieve 5 several guiding devices 18 , in particular a plurality of baffles 18.1 arranged, which by the as Siebzug-Presswalze 15.1 trained guide roller 15 by the centrifugal force at the roll circumference centrifuged centrifugal water W (arrow) merge, field and known to those skilled means, such as a white water channel 19 , pay off.

It is also above that of the Siebzug press roll 15.1 trained guide roller 15 remote sieve 5 an exhaust device 20 , in particular an evacuated exhaust duct 20.1 including guide device 20.2 arranged, which captures and discharges the air L (arrow) with the centrifugal water W (arrow).

In the area of as Siebzug-Presswalze 15.1 trained guide roller 15 is a parallel to the roll axis 15.A as a screen-pull press roll 15.1 trained guide roller 15 extending, on the outer peripheral surface 15.F as a screen-pull press roll 15.1 trained guide roller 15 rolling and preferably resilient support roller 21 arranged as the Siebzug press roll 15.1 trained guide roller 15 at least in sections, preferably along its entire width B (arrow) touched and substantially, preferably completely for receiving the resulting force F (arrow) contributes.

Such a backup roller 21 is for example in the document DE 102 59 607 A1 , the content of which is hereby made the subject of the present description.

The back-up roll 21 is designed as a deflection-supported roll known to the person skilled in the art and / or it is provided with at least one roll embossing and / or at least one roll bandage 22 for the purpose of intermittent support of as Siebzug-press roll 15.1 trained guide roller 15 provided (see. 2 ). A single drum bandage 22 is basically an annular area of the outer peripheral surface 21.A the back-up roll 21 that has a larger outer diameter than the rest of the backing roll 21 having.

A deflection-supported roller is for example from the document DE 101 12 202 A1 The content of which is hereby made the subject of the present description.

Furthermore, several known to those skilled scraper devices 23 for the purpose of conditioning the corresponding adjacent roll surfaces provided on the as a Siebzug-press roll 15.1 trained guide roller 15 , on the back-up roller 21 and on a guide roll 24 for the removed sieve 5 Act. Such scraper devices 23 are well known to those skilled in the art from a variety of references and application.

Between the as Siebzug-press roll 15.1 trained guide roller 15 and the vacuum cleaner 17.1 , So the separator 17 is at least one bar 25 , in particular a ceramic strip 25.1 including drainboard 26 for the purpose of wiping off the tread of the sieve 4 adhering white water W (arrow) arranged. And between the bar 25 and the vacuum cleaner 17.1 in turn, a spray tube known to those skilled in the art 27 provided, which is the tread of the screen 4 conditioned with a fluid M (dashed line).

The as a guide roller 15 trained Siebzug-press roll 15.1 has a roller surface 15.F with a storage volume 15.SV on, so that from the fibrous web to be produced 2 dewatered white water W (arrow) can be added. The storage volume 15.SV the roll surface 15.F includes incorporated wells 28 , in particular parallel radial or angled and / or parallel spiral grooves, bores or the like and the roll surface 15.F itself has a land area 15.LF of ≥ 40%, preferably ≥ 50%, in particular ≥ 60%, of the theoretical roll surface 15.Ftheo on (cf. 3 and 4 ).

The 2 shows a schematic view of the deflection of a preferred embodiment of a twin-wire former according to the invention 1 for a machine 100 for producing a fibrous web from at least one pulp suspension. For the sake of clarity, the illustration of the two screens and the fibrous web moved and manufactured in a sandwich were omitted.

In the area of as Siebzug-Presswalze 15.1 trained guide roller 15 is a parallel to the roll axis 15.A as a screen-pull press roll 15.1 trained guide roller 15 extending, on the outer peripheral surface 15.F as a screen-pull press roll 15.1 trained guide roller 15 rolling and preferably resilient support roller 21 arranged as the Siebzug press roll 15.1 trained guide roller 15 at least in sections, preferably along its entire width B (arrow) touched and substantially, preferably completely for receiving the resulting force F (arrow) contributes.

The back-up roll 21 is designed as a deflection-supported roll known to the person skilled in the art and / or it is provided with at least one roll embossing and / or at least one roll bandage 22 for the purpose of intermittent support of as Siebzug-press roll 15.1 trained guide roller 15 Mistake. A single drum bandage 22 is basically an annular area of the outer peripheral surface 21.A the back-up roll 21 that has a larger outer diameter than the rest of the backing roll 21 having. In the present exemplary embodiment, the support roller 21 two roller bandages 22 on.

The two 3 and 4 show schematic and partial sectional views of two preferred embodiments of roll surfaces 15.F each as a guide roller 15 executed sieve suction press rolls 15.1 of twin-wire formers according to the invention 1 for a machine 100 for producing a fibrous web from at least one pulp suspension.

The respective as a guide roller 15 trained Siebzug-press roll 15.1 has, as already stated, a roller surface 15.F with a storage volume 15.SV on, so that from the fibrous web to be produced 2 dewatered white water W (arrow) can be recorded (see also 1 ). The storage volume 15.SV the roll surface 15.F includes incorporated wells 28 , in particular parallel radial or angled and / or parallel spiral grooves, bores or the like and the roll surface 15.F itself has a land area 15.LF of ≥ 40%, preferably ≥ 50%, in particular ≥ 60%, of the theoretical roll surface 15.Ftheo on. The illustrated, as radial grooves 28.1 trained and the storage volume 15.SV the roll surface 15.F forming depressions 28 have a square groove cross-section as shown 28.Q on. However, they can of course also have a triangular, triangular and / or polygonal groove cross-section, both alone and in combination. The triangular groove cross section of the radial grooves can have at least one groove groove on the base side.

The roll surface 15.F preferably consists of a plastic coating 29 , in turn, as shown, of individual coating segments 29.S can exist in the then the individual radial grooves 28.1 are introduced.

The roll surface may also consist of a multiplicity of rings adjacent to the roll axis, in particular steel rings or the like, or of at least one steel strip wound spirally around the roll shell, in which case the rings or the at least one steel strip have a contoured profile cross section for an optimized application or . having.

In the embodiment of the 3 have the square groove cross sections 28.Q the radial grooves 28.1 parallel groove walls 28.W in, in the embodiment of 4 In contrast, the quadrangular groove cross sections 28.Q the radial grooves 28.1 angled groove walls 28 on.

Also suitable in each of the 1 to 4 at least partially illustrated twin-wire former 1 for use in a machine 100 for producing a fibrous web 2 , in particular a paper, board or packaging paper web, from at least one pulp suspension 3 ,

In summary, it should be noted that a twin-wire former of the type mentioned above is improved by the invention such that the aforementioned disadvantages of the prior art as far as possible, preferably completely eliminated. In this case, an increase in the previous dry content in the fibrous web to be produced with a significantly lower energy consumption is possible and also the acquisition and operating costs of the mechanical equipment are as possible reduced.

LIST OF REFERENCE NUMBERS

1

twin

2

Fibrous web

3

Fibrous suspension

4

First sieve

4.S

wire loop

5

Second sieve

5.S

wire loop

6

deflector; breast roll

7

peripheral region

8th

deflector; breast roll

9

peripheral region

10

Stock inlet gap

11

headbox

12

twin-wire

13

Forming and / or drainage element

14

end

15

guide roll

15.1

Wire draw-press roll

15.A

roll shaft

15.D

Roll diameter

15.F

Outer circumferential surface; roll surface

15.F _theo

Theoretical roll surface

15.LF

land area

15.SV

storage volume

16

peripheral region

17

separator

17.1

suction separator

18

guide

18.1

baffle

19

White water channel

20

exhaust device

20.1

exhaust duct

20.2

guide

21

supporting roll

21.A

Outer circumferential surface

22

roller tire

23

doctor means

24

guide roll

25

strip

25.1

ceramic bar

26

flow sheet

27

spray wand

28

deepening

28.1

radial grooves

28.Q

Groove section

28.W

groove wall

29

Plastic coating

29.S

coating segment

100

Machine for producing a fibrous web

B

Width (arrow)

F

Resulting force (arrow)

L

Air (arrow)

M

fluid

p

dewatering pressure

R

Sieblaufrichtung (arrow)

S

screen tension

W

white water; Spin water (arrow)

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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 assumes no liability for any errors or omissions.

Cited patent literature

• DE 20104380 U1 [0002]
• DE 10259607 A1 [0020, 0044]
• DE 10112202 A1 [0022, 0046]

Claims (15)

Twin wire former ( 1 ) for a machine ( 100 ) for producing a fibrous web ( 2 ), in particular a paper, board or packaging paper web, from at least one pulp suspension ( 3 ), with two endless, one wire loop each ( 4.S . 5.S ) forming sieves ( 4 . 5 ), of which the first sieve ( 4 ) over a peripheral area ( 7 ) of a first deflecting element ( 6 ) and the second sieve ( 5 ) over a peripheral area ( 9 ) a second deflecting element ( 8th ), the two sieves ( 4 . 5 ) to form a wedge-shaped material inlet gap ( 10 ) directly from a headbox ( 11 ) the at least one pulp suspension ( 3 ), in the region of the first deflecting element of the first sieve or after the expiration of the two sieves ( 4 . 5 ) of the respective deflection element ( 6 . 8th ) and then a twin-wire ( 12 ), in which the two sieves ( 4 . 5 ) first via forming and / or drainage elements ( 13 ) and in their end region ( 14 ) the two screens over a peripheral area ( 16 ) a guide roller ( 15 ) are guided, wherein directly or indirectly after the guide roller ( 15 ) - seen in the direction of wire drainage (R) - at least one separating device ( 17 ), in particular a separating sucker ( 17.1 ) or a separation roller for separating the one sieve ( 5 ) from the other sieve ( 4 ) with the fibrous web lying thereon and to be produced ( 2 ), characterized in that the guide roller ( 15 ) as a wire draw press roll ( 15.1 ) whose drainage pressure (p) is between the two sieves ( 4 . 5 ) to be produced fibrous web ( 2 ) is generated by the applied wire tension (S). Twin wire former ( 1 ) according to claim 1, characterized in that the as Siebzug-Presswalze ( 15.1 ) formed guide roller ( 15 ) a roll diameter ( 15.D ) in the range of 100 to 2,000 mm, preferably from 200 to 1,500 mm, in particular from 300 to 1,000 mm. Twin wire former ( 1 ) according to claim 1 or 2, characterized in that above that of the Siebzug press roll ( 15.1 ) trained guide roller ( 15 ) facing away sieve ( 5 ) several guide devices ( 18 ), in particular a plurality of baffles ( 18.1 ) are arranged, which by the as Siebzug-Presswalze ( 15.1 ) trained guide roller ( 15 ) by the centrifugal force at the roll circumference centrifuged centrifugal water (W) merge, collect and dissipate. Twin wire former ( 1 ) according to one of the preceding claims, characterized in that above that of the Siebzug press roll ( 15.1 ) trained guide roller ( 156 ) facing away sieve ( 5 ) at least one exhaust device ( 20 ), in particular an evacuated exhaust duct ( 20.1 ) which collects and discharges the air (L) introduced with the spin water (S). Twin wire former ( 1 ) according to any one of the preceding claims, characterized in that the as Siebzug-Presswalze ( 15.1 ) formed guide roller ( 15 ) a roll surface ( 15.F ) with a storage volume ( 15.SV ), so that from the fibrous web to be produced ( 2 ) dewatered white water (W) can be absorbed. Twin wire former ( 1 ) according to claim 5, characterized in that the storage volume ( 15.SV ) of the roll surface ( 15.F ) incorporated wells ( 28 ), in particular parallel radial or angled and / or parallel spiral grooves, bores or the like, and in that the roll surface ( 15.F ) a land area ( 15.LF ) of ≥ 40%, preferably ≥ 50%, in particular ≥ 60%, of the theoretical roll surface ( 15.Ftheo ) having. Twin wire former ( 1 ) according to claim 6, characterized in that the radial grooves ( 28.1 ) and the storage volume ( 15.SV ) of the roll surface ( 15.F ) forming depressions ( 28 ) a triangular, triangular, square and / or polygonal groove cross-section ( 28.Q ) exhibit. Twin wire former ( 1 ) according to claim 7, characterized in that the triangular groove cross section of the radial grooves has at least one base groove radius. Twin wire former ( 1 ) according to claim 7, characterized in that the quadrangular groove cross-section ( 28.Q ) of the radial grooves ( 28.1 ) parallel or angled groove walls ( 28.W ) having. Twin wire former ( 1 ) according to any one of the preceding claims, characterized in that in the region of the as Siebzug-Presswalze ( 15.1 ) trained guide roller ( 15 ) at least one parallel to the roll axis ( 15.A ) as Siebzug-press roller ( 15.1 ) trained guide roller ( 15 ) extending, on the outer peripheral surface ( 15.F ) as Siebzug-press roller ( 15.1 ) trained guide roller ( 15 ) rolling and preferably resilient support roller ( 21 ) arranged as the Siebzug-press roller ( 15.1 ) formed guide roller ( 15 ) at least in sections, preferably along its entire width (B) touched and substantially, preferably completely for receiving the resulting force (F) contributes. Twin wire former ( 1 ) according to claim 10, characterized in that the support roller ( 21 ) is formed as a deflection-supported roller. Twin wire former ( 1 ) according to claim 10 or 11, characterized in that the support roller ( 21 ) with at least one roll embossing and / or at least one roll bandage ( 22 ) for the purpose of intermittent support of the as Siebzug-Presswalze ( 15.1 ) trained guide roller ( 15 ) is provided. Twin wire former ( 1 ) according to one of the preceding claims, characterized in that at least one scraper device ( 23 ) for the purpose of conditioning the adjacent roll surface ( 15.F ) is provided. Twin wire former ( 1 ) according to any one of the preceding claims, characterized in that between the as Siebzug-Presswalze ( 15.1 ) trained guide roller ( 15 ) and the separating device ( 17 ), in particular the separating sucker ( 17.1 ) at least one bar ( 25 . 25.1 ) for the purpose of wiping off the tread ( 4 ) adhering white water (W) is arranged. Machine ( 100 ) for producing a fibrous web ( 2 ), in particular a paper, board or packaging paper web, from at least one pulp suspension ( 3 ), characterized in that it comprises at least one twin-wire former ( 1 ) according to one of the preceding claims.

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