EP2096207A1 - Inclined screen former of a machine for producing a sheet of fibrous material from at least one fibrous suspension - Google Patents

Abstract

The former (1) has a dehydration element (11) arranged in a lower side of a screen (4) and dehydrating a fiber suspension (3) applied on an upper side of the screen. A suction former roller (20) downstream to the dehydration element is arranged in a screen loop (5) of the screen. The former roller has a suction zone (Z20.1) subjected with a controllable/regulatable low pressure and a roller diameter in a range of 1.000 t0 1.400 millimeters. The suction zone is completely or partially covered by an upper lip (22) that is curved and arranged at a front wall (10) of a headbox (9).

Description

The invention relates to a Schrägsiebformer a machine for producing a fibrous web, in particular a Langfaserpapier- or wet nonwoven web, at least one pulp suspension, with a forming a wire loop screen which runs over a peripheral region of a breast roll and then at least in sections in the direction of wire running at an angle to the horizontal , wherein in this running at an angle to the horizontal line section of the screen at least one headbox at least one fibrous suspension on the top of the screen and the underside of the screen at least one dewatering element for dewatering the at least one top side applied to the screen pulp suspension is arranged.

Such a Schrägsiebformer is for example from the German patent application DE 10 2004 047 518 A1 and is manufactured and sold by the applicant under the name "Hydroformer". It is used primarily for the production of long fiber papers and wet nonwovens, this type of sheet formation fibers and fiber mixtures of various materials are used with a length of 1 to 40 mm.

In this known Schrägsiebformer the sieve extends after the expiration of the breast roll initially at an angle of approximately + 20 ° to the horizontal. In this oblique stretch of the screen, the headbox brings the pulp suspension on top of the sieve. On the underside of the screen, a drainage element in the form of a multi-zone suction box for dewatering the pulp suspension applied on the top side of the screen is arranged.

The headbox is arranged such that it applies in the region of the dewatering element, the entire pulp suspension on the screen, so the front wall of the headbox ends in the end region of the dewatering element and thus forms an outlet gap. At the end of the oblique stretch section, the wire together with the overlying and produced fibrous web is guided over a guide roll or buckling roll before the fibrous web to be produced is removed in a known manner by means of a pickup roll from the falling wire and fed to further machine sections. The sieve is then returned to the breast roll via several guide rollers. During this recycling, the screen is usually cleaned by means of a known cleaning device. Further, between the dewatering element and the buckling roll, a plurality of slit suckers are usually arranged for further increasing the dry content in the fibrous web to be produced. Depending on the grade and quality of the fibrous web to be produced, web speeds of up to 600 m / min can be achieved with such a type of inclined wire former.

The disadvantage of such Schrägsiebformer, however, is that it can come at high vacuums in the slot vacuum cleaner to a fleece accumulation in front of the slotted suction, which nonwoven congestion can in turn lead to wrinkling in the fibrous web to be produced. Moreover, the strong deflection of the fibrous web to be produced in the area of the buckling roll causes lifting of the fibrous web to be produced, especially at higher web speeds, which in turn can lead to wrinkling or even to a web break. The risk of lifting off the fibrous web to be produced is particularly given in the production of glass nonwoven webs which have little or no connection to the wire.

It is therefore an object of the invention to develop a Schrägsiebformer of the type mentioned in such a way that the mentioned disadvantages of the prior art as far as possible, preferably even completely avoided. In particular, the production of a high-quality fibrous web at clearly allows higher web speeds and at the same time the runnability of Schrägsiebformers be increased significantly.

This object is achieved in a Schrägsiebformer the aforementioned type according to the invention that the dewatering element is arranged downstream in the wire loop of the screen Saugformierwalze, both a roll diameter in the range of 800 to 1500 mm, preferably from 900 to 1450 mm, in particular of 1,000 to 1,400 mm, as well as at least one having a preferably controllable / controllable negative pressure acted upon suction zone, wherein the at least one suction zone of the Saugformierwalze is completely or partially covered by a arranged on the front wall of the headbox and curved upper lip.

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

The use of the Saugformierwalze described, which can be driven or driven depending on the use, on the one hand brings the advantage that the dry content of the fibrous web to be produced even without the use of the usual slotted suction noticeably and reliably, that can be increased without fleece backlog and possible associated wrinkling On the other hand, a lifting of the fibrous web to be produced in the deflection area including possible wrinkling or even possible web break is completely avoided. Moreover, the use of the described suction forming roll opens up the possibility of realizing web speeds of over 1,000 m / min, even in the production of a high-quality fibrous web.

In order to provide adequate drainage capacity and guiding security for the fibrous web to be produced on the suction forming roll, it preferably has a suction roll jacket having an open area in the range of 40 to 80%, preferably 50 to 75%. The Saugwalzenmantel the Saugformierwalze here may comprise a honeycomb cylinder, a fabric with a coarse mesh or a wrapping wire spiral, said Mantelarten merely exemplary character and are well known to those skilled.

With regard to a gentle but effective dewatering of the fibrous web to be produced, it is advantageous if the preferably controllable negative pressure in the suction zone of the suction forming roll has a value in the range from 0.1 to 0.8 bar, preferably from 0.2 to 0, 5 bar, accepts. The generation of the preferably controllable / controllable negative pressure can in this case take place in a known manner by means of at least one negative pressure generating unit, for example a motor driven vacuum pump.

Furthermore, the Saugformierwalze preferably at least two, each having a preferably controllable / controllable negative pressure acted upon suction zones, wherein at least one suction zone of the Saugformierwalze is completely or partially covered by the arranged on the front wall of the headbox and curved upper lip. In this case, the preferably controllable negative pressures in the suction zones of the suction forming roller can favorably assume different values in the range from 0.1 to 0.8 bar, preferably from 0.2 to 0.5 bar, and / or the suction zones of the suction forming roller may have increasing negative pressures in the direction of the wire run. By means of these design options, the dewatering of the fibrous web to be produced can be adjusted specifically and adapted to the production and material properties. Thus, for example, the at least one preferably controllable / controllable negative pressure on the suction forming roll is preferably adjustable in such a way that at least 5 and at most 30% of the amount of pulp suspension supplied to the headbox is dewatered with the suction forming roll.

With regard to a sufficient drainage length with a maximum of space available, it is advantageous if the at least one dewatering element is a suction box which has a plurality of suction zones with preferably controllable / controllable negative pressures in the direction of the wire flow. In a known manner, a suction box allows a comparatively large dewatering length if necessary low height. The preferably controllable negative pressures in the suction zones of the suction box can assume different values in the range from 0.1 to 0.7 bar, preferably from 0.2 to 0.6 bar, in order to achieve effective dewatering. Also, the preferably controllable negative pressures in the suction zones of the suction box can be adjusted in such a way that at least 70 and at most 95% of the amount of pulp suspension supplied to the head box is dewatered with the suction box. Furthermore, the suction box can have a suction box covering comprising strips and / or panels, in order to sufficiently take into account different aspects, such as functional safety, freedom from marking in the fibrous web to be produced, and the like. In addition, such a Saugkastenbelag is technologically mature due to its diverse use in the production of fibrous webs of different qualities and also low in the purchase and operation.

So that the curved upper lip of the headbox can be positioned on the upstream side independently of or largely independent of the preferably straight front wall of the headbox, it is preferably connected to it by means of at least one rotary joint. The swivel joint can be sectioned over the width of the headbox in a known manner and the curvature of the upper lip at least substantially corresponds to the diameter of the Saugformierwalze. In addition, the curved upper lip of the headbox and the preferably straight front wall of the headbox can be individually positioned from each other. It can also be provided that the curved upper lip of the headbox and the preferably straight front wall of the headbox are lifted together by means of a quick lift of the sieve.

Furthermore, the at least one headbox is preferably arranged such that in the region of the at least one drainage element it preferably applies the pulp suspension completely to the top side of the sieve. Thus, an at least small, preferably process-technologically sufficient dewatering of the topside applied to the screen pulp suspension is given.

It can also be provided that the at least one headbox is designed as a multi-layer headbox, wherein the delamination between two adjacent layers is effected by a flexibly arranged separating element. In this case, the at least one headbox may have a sectioned substance density control for at least one layer of the headbox or multilayer headbox. These possibilities allow the production of fibrous webs with different qualities with only minor changes in mechanical engineering.

Depending on the arrangement and orientation of the Schrägsiebformers in possibly given space, the angle to the horizontal assumes a value in the range of 0 to 45 °, preferably from 5 to 30 °, in particular from 10 to 20 °. Thus, the Hauptentwässerungsstrecke of Schrägsiebformers in individual cases and in full compliance with technological requirements may also be aligned horizontally or approximately horizontally.

It is understood that the features of the invention mentioned above and those yet to be explained can not be used in the particular combination given, but also in other combinations and in isolation, without departing from the scope of the invention.

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

Figur 1

eine schematische Seitenansicht eines Schrägsiebformers einer Maschine zur Herstellung einer Faserstoffbahn gemäß dem Stand der Technik;

Figuren 2, 4 und 5

jeweils eine schematische Seitenansicht einer erfindungsgemäßen Ausführungsform eines Schrägsiebformers einer Maschine zur Herstellung einer Faserstoffbahn; und

Figur 3

eine vereinfachte Detailansicht der Saugformierwalze der in der Figuren 2, 4 und 5 dargestellten Schrägsiebformer einer Maschine zur Herstellung einer Faserstoffbahn.

Show it

FIG. 1

a schematic side view of a Schrägsiebformers a machine for producing a fibrous web according to the prior art;

FIGS. 2, 4 and 5

in each case a schematic side view of an embodiment according to the invention of a Schrägsiebformers a machine for producing a fibrous web; and

FIG. 3

a simplified detailed view of the Saugformierwalze in the Figures 2 . 4 and 5 shown Schrägsiebformer a machine for producing a fibrous web.

The FIG. 1 shows a schematic side view of a Schrägsiebformers 1 of a machine for producing a fibrous web 2, in particular a long fiber paper or wet nonwoven web, from at least one pulp suspension. 3

The Schrägsiebformer 1 has a sieve loop 5 forming sieve 4, which runs over a peripheral region 7 of a breast roll 6 and then in the wire direction S (arrow) at least in sections at an angle α obliquely to the horizontal H. The angle α assumes a value of approximately + 20 ° to the horizontal. It brings in this oblique stretch section 8 of the screen 4, a front wall 10 having and merely indicated headbox 9, the pulp suspension 3 on the top of the sieve 4 and on the underside a drainage element 11 is arranged for dewatering the top of the sieve 4 applied pulp suspension 3. The headbox 9 is arranged such that it applies in the region of the dewatering element 11, the full pulp suspension 3 on the top of the sieve 4, the front wall 10 of the headbox 9 thus ends in the end region of the dewatering element 11 and thus forms an outlet gap A. Alternatively, the dewatering element 11 could also go beyond the application area of the headbox 9.

At the end of the oblique stretch section 8, the wire 4 together with overlying and manufactured fibrous web 2 is guided over a guide or bending roll 12, before the fibrous web 2 to be produced in a known manner by means of a known to the expert pickup roller 13 from the sloping sieve 4 and further machine sections, not shown, is supplied. The screen 4 is then returned to the breast roll 6 via a plurality of guide rollers 14. there For example, a guide roll 14 may be formed as a wire-width stretch roll known in the art.

Further, between the dewatering element 11 and the bending roll 12 a plurality of, in the present embodiment, two known to those skilled slot suction 15 for further increase in dry content in the fibrous web 2 to be produced are arranged. With such a design of the Schrägsiebformers 1, depending on the grade and quality of the fibrous web 2 to be produced, web speeds v (arrow) of up to 600 m / min can be achieved.

The dewatering element 11 is in the embodiment according to the FIG. 1 So, according to the prior art, a suction box 16, the S in the direction S (arrow), for example, six suction zones Z _16.1 to Z _16.6 . The number of suction zones Zn of the suction box 16 generally moves between 4 and 8, preferably between 5 and 7. The suction zones Z _16.1 to Z _{16.6 of} the illustrated suction box 16 can be acted upon by at least two different subpressures U _17.1 , U _17.2 , that of two separate negative pressure sources 17.1, 17.2 (arrows) for the zones Z _16.1 , Z _16.3 , Z _16.5 and Z _16.2 , Z _16.4 , Z _{16.6 are} generated. The vacuum sources 17.1, 17.2 (arrows) can be designed, for example, as preferably controllable / controllable vacuum pumps. Of course, only a vacuum source may be present, which preferably engages in the lower region of the suction box. The drawn in the suction box 16 from the pulp suspension 3 white water 18 (arrow) is by means of a white water drain off and the known white water circuit fed. Also, instead of a single suction box 16 several successively arranged suction boxes may be present.

The suction box 16 is provided on the upper side with a strip covering 19, but it can of course also have a known plate covering.

The FIG. 2 shows a schematic side view of a first embodiment according to the invention of a Schrägsiebformers 1 of a machine for manufacturing a fibrous web 2. Since the basic structure of this Schrägsiebformers 2 in large parts of the basic structure of in the FIG. 1 shown and described Schrägsiebformers 1, reference is hereby made to its description.

Unlike the one in the FIG. 1 shown Schrägsiebformer 1 according to the prior art, the Schrägsiebformer 1 of this figure on the dewatering element immediately downstream slotted vacuum cleaner for further increase in dry content of up to 5% in the fibrous web 2 to be produced. Instead, the dewatering element 11 is followed by a suction forming roll 20 arranged in the wire loop 5 of the wire 4, which has both a roll diameter D ₂₀ in the range of 800 to 1,500 mm, preferably 900 to 1,450 mm, in particular 1,000 to 1,400 mm, and at least one having a preferably controllable / controllable negative pressure acted upon suction zone. In the present embodiment, the Saugformierwalze 20 has two each with a preferably regulable / controllable vacuum U _20.1 , U _20.2 acted upon suction zones Z _20.1 , Z _20.2 . Furthermore, at least one suction zone Z _20.1 , Z _{20.2 of} the suction forming roller 20 is completely covered (suction zone Z _20.1 ) or partially (suction zone Z _20.2 ) by a top lip 22 arranged on the front wall 10 of the headbox 9. In addition, the suction forming roll 20 may be driven or driven as shown, depending on use.

Moreover, the suction forming roll 20 has a suction roll shell 23 having an open area F ₂₃ in the range of 40 to 80%, preferably 50 to 75%. The Saugformierwalze 20 of the in FIG. 2 Schrägsiebformers 1 thus replaced also the guide or buckling roller 12 of the in the FIG. 1 shown Schrägsiebformers. 1

Furthermore, the curved upper lip 22 of the headbox 9 is connected by means of at least one rotary joint 24 with the preferably straight front wall 10 of the headbox 9, so that the curved upper lip 22 of the headbox 9 and the preferably straight front wall 10 of the headbox 9 are individually positioned. The web width, optionally also sectioned positioning The curved upper lip 22 of the headbox 9 by means of a positioning device 25, for example by means of a shown and at least one lifting spindle 27 comprehensive lifting device 26. The two directions of movement of the lifting device are indicated by a double arrow.

Also, the curved upper lip 22 of the headbox 9 and the preferably straight front wall 10 of the headbox 9 can be lifted together by means of a quick lift of the sieve 4. The rapid lifting takes place, for example, by means of a lifting device 28 which is shown and which comprises at least one lifting cylinder 29. The two directions of movement of the lifting device are indicated by means of a double arrow.

The dewatering element 11 is in the embodiment according to the FIG. 2 in turn, a suction box 30, the S in the direction S (arrow), for example, seven suction zones Z _30.1 to Z _30.7 . The preferably controllable negative pressures U _31.1 to U _31.3 in the suction zones Z _30.1 to Z _{30.7 of} the suction box 30 assume different values in the range from 0.1 to 0.7 bar, preferably from 0.2 to 0.6 bar , The vacuum sources 31.1 to 31.3 (arrows) required for this purpose can be designed, for example, as preferably controllable / controllable vacuum pumps. The white water removed in the region of the suction box 30 from the pulp suspension 3 is removed by means of a white water drain and fed to the known white water circuit. The illustrated embodiment is merely exemplary in nature. Of course, other embodiments with regard to the number of different negative pressures, together with vacuum applied suction zones and the like possible. Thus, for example, the preferably controllable negative pressures U _30.1 to U _30.3 in the suction zones Z _30.1 to Z _{30.7 of} the suction box 30 are adjustable so that with the suction box 30 at least 70 and a maximum of 95% of the headbox 9 supplied amount of pulp suspension 3 dehydrates becomes.

The angle α to the horizontal H usually takes a value in the range of 0 to 45 °, preferably from 5 to 30 °, in particular from 10 to 20 °, and the suction box 30 is also provided on the upper side with a last covering 32, but it can of course have a known plate covering.

With such a design of the Schrägsiebformers 1, depending on the grade and quality of the fibrous web 2 to be produced, web speeds v (arrow) of up to 1,000 m / min can be achieved.

The FIG. 3 now shows a simplified detailed view of the Saugformierwalze 20 of the in the FIG. 2 shown Schrägsiebformers 1 a machine for producing a fibrous web. 2

The Saugformierwalze 20 has, as already stated, a roller diameter D ₂₀ in the range of 800 to 1,500 mm, preferably from 900 to 1,450 mm, in particular from 1,000 to 1,400 mm, as well as two, each with a preferably controllable / controllable negative pressure U _20.1 , U _20.2 acted upon suction zones Z _20.1 , Z _20.2 on. The respective negative pressure U _20.1 , U _20.2 in the corresponding suction zone Z _20.1 , Z _{20.2 of} the Saugformierwalze 20 assumes a value in the range of 0.1 to 0.8 bar, preferably from 0.2 to 0.5 bar, wherein the Negative pressures U _20.1 , U _{20.2 increase} in the direction of sweep S (arrow). Ultimately, the two acting on the Saugformierwalze 20 subpressures U _20.1 , U _{20.2 are} adjustable so that with the Saugformierwalze 20 at least 5 and a maximum of 30% of the headbox 9 ( FIG. 2 ) is dewatered amount of pulp suspension 3. The two suction zones Z _20.1 , Z _20.2 are acted upon by two vacuum sources 21.1, 21.2 (arrows).

The first suction zone Z _{20.1 of} the suction forming roller 20 is in the direction of the direction of the wire flow S (arrow), and the second suction zone Z _20.2 in the direction of the wire flow S (arrow) is partially replaced by the one on the front wall 10 of the headbox 9 (FIG. FIG. 2 ) arranged and curved upper lip 22 is covered, which is connected by means of at least one rotary joint 24 with the preferably straight front wall 10 of the headbox 9.

In addition, the suction roll shell 23 of the suction forming roll 20 has an open area F ₂₃ in the range of 40 to 80%, preferably 50 to 75%, and may comprise a illustrated honeycomb cylinder 33, coarse mesh fabric or wrapping wire spiral. And between the strip covering 32 of the suction box 30 and the Saugformierwalze 20 a sealing strip 36 is arranged.

The FIG. 4 shows a schematic side view of a second embodiment according to the invention Schrägsiebformers a machine 1 for producing a fibrous web 2. Since the basic structure of this Schrägsiebformers 2 in large parts of the basic structure of the in FIG. 2 shown and described Schrägsiebformers 1, reference is hereby made to its description.

Unlike the one in the FIG. 2 Schrägsiebformer 1 shown assumes the angle α to the horizontal H in this illustrated Schrägsiebformer 1 a value in the range of 0 °, that is, the stretch section 8 after the breast roll 6 is horizontal. As a result, the structure and thus the appearance of the frame 34 of the Schrägsiebformers 1 changes accordingly.

And the FIG. 5 shows a schematic side view of a third embodiment according to the invention of a Schrägsiebformers 1 of a machine for producing a fibrous web 2. Since the basic structure of this Schrägsiebformers 2 in many parts of the basic structure of in the FIG. 2 shown and described Schrägsiebformers 1, reference is hereby made to its description.

Unlike the one in the FIG. 2 Slant former 1 shown, the headbox is designed as a multi-layer headbox 9.1, especially as a three-layer headbox, wherein the delamination between two adjacent layers is effected by a flexibly arranged separating element 35. Generally, the single separator 35 may be made of a stainless steel or the like and have a minimum rigidity both in the machine direction and in the machine direction Have cross-machine direction, the area assumes at least a value ≥ 40 N / mm. Also, this multi-layer casserole 9.1 as well as each in the Figures 2 and 4 Headbox 9 shown have a sectioned fabric density control for at least one layer. Such a sectioned consistency control is, for example, in the German patent DE 40 19 593 C2 shown and described.

In summary, it can be stated that a Schrägsiebformer of the aforementioned type is provided by the invention, which avoids the disadvantages of the prior art as far as possible, preferably even completely avoided. In particular, the production of a high-quality fibrous web is made possible at significantly higher web speeds and at the same time the runnability of the inclined wire former is markedly increased.

LIST OF REFERENCE NUMBERS

1

Schrägsiebformer

2

Fibrous web

3

Fibrous suspension

4

scree

5

wire loop

6

breast roll

7

peripheral region

8th

stretch

9

headbox

9.1

Multi-layer headbox

10

front wall

11

dewatering element

12

Guide or bending roll

13

Pickup roll

14

guide roll

15

slotted suction

16

suction box

17.1

Low pressure source (arrow)

17.2

Low pressure source (arrow)

18

White water (arrow)

19

bars lining

20

suction forming roll

21.1

Low pressure source (arrow)

21.2

Low pressure source (arrow)

22

upper lip

23

suction roll

24

swivel

25

positioning

26

lifting device

27

lifting spindle

28

lifting device

29

lifting cylinder

30

suction box

31.1

Low pressure source (arrow)

31.2

Low pressure source (arrow)

31.2

Low pressure source (arrow)

32

bars lining

33

honeycomb cylinder

34

framing

35

separating element

36

sealing lip

A

outlet gap

D ₂₀

Roll diameter

F ₂₃

Open area

H

horizontal

S

Sieblaufrichtung (arrow)

U _17.1

vacuum

U _17.2

vacuum

U _21.1

vacuum

U _21.2

vacuum

U _31.1

vacuum

U _31.2

vacuum

U _31.3

vacuum

v

Path speed (arrow)

Z _16.1 to Z _16.6

suction zone

Z _20.1 , Z _20.2

suction zone

Z _30.1 to Z _30.7

suction zone

α

angle

Claims (15)

Slanted wire former (1) of a machine for producing a fibrous web (2), in particular a long fiber paper or wet nonwoven web, from at least one pulp suspension (3), with a sieve (4) forming a sieve loop (5), which extends over a peripheral region (7) Breast roller (6) runs and then in the wire direction (S) at least in sections at an angle (α) to the horizontal (H), wherein in this at an angle (α) to the horizontal (H) extending track section (8) of the sieve (4 ) at least one headbox (9; 9.1) applying at least one pulp suspension (3) on top of the sieve (4) and at least one drainage element (11) for dewatering the at least one upper side on the sieve (4) on the underside of the sieve (4) Fibrous suspension (3) is arranged,
characterized,
in that a dewatering roller (20) arranged in the wire loop (5) of the wire (4) is arranged downstream of the dewatering element (11) and has both a roller diameter (D ₂₀ ) in the range of 800 to 1,500 mm, preferably 900 to 1,450 mm, in particular from 1,000 to 1,400 mm, and at least one with a preferably controllable negative pressure (U _21.1 , U _21.2 ) acted upon suction zone (Z _20.1 , Z _20.2 ), wherein the at least one suction zone (Z _20.1 , Z _20.2 ) of the Saugformierwalze (20) wholly or partially by a on the front wall (10) of the headbox (9, 9.1) arranged and curved upper lip (22) is covered. An inclined wire former (1) according to claim 1,
characterized,
in that the suction forming roll (20) has a suction roll jacket (23) with an open area (F ₂₃ ) in the range from 40 to 80%, preferably from 50 to 75%. An inclined wire former (1) according to claim 2,
characterized,
in that the suction roll jacket (23) of the suction forming roll (20) comprises a honeycomb cylinder (33), a covering with a coarse mesh fabric or a wound wire spiral. An inclined wire former (1) according to one of the preceding claims,
characterized,
in that the preferably controllable negative pressure (U _21.1 , U _21.2 ) in the suction zone (Z _20.1 , Z _20.2 ) of the suction forming roll (20) has a value in the range from 0.1 to 0.8 bar, preferably from 0.2 to 0.5 bar, assumes. An inclined wire former (1) according to one of the preceding claims,
characterized,
in that the suction-forming roll (20) has at least two suction zones (Z _20.1 , Z _20.2 ), each having a preferably controllable negative pressure (U _21.1 , U _21.2 ), wherein at least one suction zone (Z _20.1 , Z _20.2 ) of the suction-forming roll (20 ) is completely or partially covered by the upper lip (22) arranged on the front wall (10) of the headbox (9; An inclined wire former (1) according to claim 5, characterized
characterized,
that the preferably controllable negative pressures (U _21.1 , U _21.2 ) in the suction zones (Z _20.1 , Z _20.2 ) of the suction forming roll (20) have different values in the range from 0.1 to 0.8 bar, preferably from 0.2 to 0.5 bar, assume. An inclined wire former (1) according to claim 5 or 6, characterized
characterized,
that the suction zones (Z _20.1 , Z _20.2 ) of the Saugformierwalze (20) in Sieblaufrichtung (S) increasing negative pressures (U _21.1 , U _21.2 ) have. An inclined wire former (1) according to one of the preceding claims,
characterized,
in that the at least one preferably controllable negative pressure (U _21.1 , U _21.2 ) on the suction forming roll (20) is adjustable such that at least 5 and at most 30% of the amount fed to the headbox (9; 9.1) with the suction forming roll (20) is dewatered on pulp suspension (3). An inclined wire former (1) according to one of the preceding claims,
characterized,
in that the at least one dewatering element (11) is a suction box (30) which has a plurality of suction zones (Z _30.1 to Z _30.7 ) with preferably controllable / controllable negative pressures (U _31.1 to U _31.3 ) in the direction of wire run (S). An inclined wire former (1) according to one of the preceding claims,
characterized,
in that the curved upper lip (22) of the head box (9, 9.1) is connected to the preferably straight front wall (10) of the head box (9, 9.1) by means of at least one rotary joint (24). An inclined wire former (1) according to one of the preceding claims,
characterized,
that the curved top lip (22) of the headbox (9; 9.1) and the preferably straight front wall (10) of the headbox (9; 9.1) are individually adjustable. An inclined wire former (1) according to one of the preceding claims,
characterized,
in that the curved upper lip (22) of the headbox (9; 9.1) and the preferably straight front wall (10) of the head box (9; 9.1) can be lifted off the wire (4) together by means of a quick lift. An inclined wire former (1) according to one of the preceding claims,
characterized,
in that the at least one headbox (9, 9.1) is arranged in such a way that it preferably applies the pulp suspension (3) completely to the sieve (4) in the region of the at least one drainage element (11). An inclined wire former (1) according to one of the preceding claims,
characterized,
in that the at least one headbox (9) is designed as a multi-layer headbox (9.1), wherein the layer separation between two adjacent layers takes place by means of a flexibly arranged separating element (35). An inclined wire former (1) according to one of the preceding claims,
characterized,
that the angle (α) to the horizontal (H) has a value in the range of 0 to 45 °, preferably from 5 to 30 °, in particular from 10 to 20 °, assumes.

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