EP0496073B1 - Formeur à double toile - Google Patents

Formeur à double toile Download PDF

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Publication number
EP0496073B1
EP0496073B1 EP91121320A EP91121320A EP0496073B1 EP 0496073 B1 EP0496073 B1 EP 0496073B1 EP 91121320 A EP91121320 A EP 91121320A EP 91121320 A EP91121320 A EP 91121320A EP 0496073 B1 EP0496073 B1 EP 0496073B1
Authority
EP
European Patent Office
Prior art keywords
forming
twin
wire former
roll
former according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP91121320A
Other languages
German (de)
English (en)
Other versions
EP0496073A1 (fr
Inventor
Alfred Dr. Bubik
Otto Hildebrand
Karl Müller
Jörg Walter
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Voith Sulzer Papiermaschinen GmbH
Original Assignee
Sulzer Escher Wyss GmbH
Escher Wyss GmbH
Voith Sulzer Papiermaschinen GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sulzer Escher Wyss GmbH, Escher Wyss GmbH, Voith Sulzer Papiermaschinen GmbH filed Critical Sulzer Escher Wyss GmbH
Publication of EP0496073A1 publication Critical patent/EP0496073A1/fr
Application granted granted Critical
Publication of EP0496073B1 publication Critical patent/EP0496073B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F9/00—Complete machines for making continuous webs of paper
    • D21F9/003—Complete machines for making continuous webs of paper of the twin-wire type

Definitions

  • the invention relates to a twin wire former according to the preamble of claim 1.
  • twin wire former is known from US Pat. No. 4,925,531, which has a forming roll with further forming sections in front of and behind it, but does not achieve the highest dewatering effect in all cases with a relatively long length.
  • twin wire former according to DE-38 15 470 A1 forming shoes, forming rollers and support surfaces are installed which are intended to guide a first or second wire.
  • the shear stress between the sieves on the suspension is weak and therefore the former has to be operated with a lot of dilution water.
  • packaging papers from 280 to 100g / m2, this leads to large overall heights of the former, which can be greater than 8 m, and requires a longer sheet formation length.
  • this twin wire former when forming the web, i.e. the formation ends at a point E of the looping length of the forming roll. However, this is followed by dewatering on a support surface and a suction roll.
  • twin-wire formers known from DE-OS 20 00 661 and DE-OS 21 02 717 show a large deflection on the forming cylinders located in the middle area, but have neither strips arranged on both sides in the forming sections lying in front of or behind them. The drainage performance is therefore often not sufficient.
  • the system according to the invention thus prevents soiling and so-called substance-fog formation.
  • good water drainage is also possible against gravity, without the need to first collect the white water via guide surfaces.
  • the forming sections are arranged essentially at an angle of 90 ° to one another.
  • One of the two forming sections can be arranged essentially horizontally.
  • the first forming section can expediently be oriented vertically in connection with a vertically directed or also inclined headbox.
  • the intermediate forming roll eliminates the need for a special suction roll. Nevertheless, the second forming section achieves a higher dry content than in the twin-wire former of DE 38 15 470 A1 using the suction roll, and also a better formation, with a relatively low deflection in combination with a low profile, especially with a small deflection over the forming roll Shear occurs, in contrast to the relatively large shear on the formed web due to the 180 ° deflection on the suction roll of DE 38 15 470 A1.
  • the forming roller lying between the stationary forming elements has a very strong influence on the drainage.
  • the redirection leads to the Forming roller so that the former can be built very compactly and at the same time the dewatering is improved by centrifugal centrifugal force.
  • the stock inlet gap can expediently be arranged above or below the first forming section.
  • the stationary forming elements can be formed by a so-called forming shoe or at least one forming pressure bar.
  • the resilient, adjustable forming pressure bars SP bars are arranged either on the left or right or above or below.
  • the forming rollers in the area of the headbox have a calming (turbulence-reducing) effect on the stock suspensions. This may be desirable, but is not always desirable. If there are no forming rollers in this area, the material with the turbulence leading from the headbox is guided into the turbulence-maintaining or reinforcing zone, which is characterized by stationary strips that touch the screen.
  • the main forming roll follows, which leads to a substantial calming of the turbulent suspension, and then another turbulence generation occurs again through the second forming section with at least one stationary forming element.
  • This second turbulence generation in particular prevents flocculation in the suspension layer.
  • the presence of a turbulence-increasing forming section after the deflection or forming roll is an important characteristic of this invention.
  • a drainage effect of approx. 20% occurs in the first, in particular vertical, forming section with the stationary forming elements.
  • a dewatering effect of approx. 40% takes place in the intermediate forming roll itself.
  • a drainage effect of approximately 20% for example.
  • the particularly advantageous embodiment of the invention with the two forming sections and the intermediate main forming roll includes an essentially vertical alignment of the first forming section, an approximately 90 ° deflection in the area of the main forming roll and an essentially horizontally oriented subsequent second forming section.
  • the length of the second forming section is expediently at least 80% of the wrap length of the forming roll lying between the forming sections. But it can also be the same or larger.
  • four to five forming bars can preferably be arranged one behind the other at a forming point.
  • At least two stationary forming elements can be arranged in essentially opposite directions in the first forming section and also in the second forming section, although they do not have to overlap one another in their full length. You can also form a forming section, which thus acts on both sides of the twin wire. This forming section is preferably shorter than the wrap length of the main forming roll lying between the forming sections.
  • one of the opposing forming elements can be designed as a forming shoe with a curved or straight contact surface and the other forming element as at least one forming pressure bar.
  • the stationary forming element located at the top can in particular be designed as a forming shoe with suction drainage.
  • the stationary forming element in particular a molded shoe, can be followed by a separating element, which is designed, for example, as a separating roller or as a separating suction device.
  • a pre-suction device can be connected upstream of the stationary forming element, in particular a forming shoe, and in particular an upper forming shoe, in the second forming section.
  • a curved forming shoe which lies in particular on the transport screen located below, can be directly connected upstream of a stationary forming element, which is in particular at the top and in particular in the form of a shoe.
  • the screen length of the first forming section (F1) touched by the forming shoe is preferably shorter than the looping length of the downstream forming roll.
  • the forming roller between the forming sections can be an open forming roller, either one whose surface is opened up by a honeycomb structure or a suction roller.
  • the active surface of the stationary shaped element can lie in the area between the upper and lower apex of the forming roller located between the forming sections.
  • the twin-wire former of the various exemplary embodiments has a first wire 10 as the transport wire and, moreover, a second wire 12.
  • the sieves move in the direction of the arrows indicated and converge in a stock inlet gap 14.
  • the sieves 10 and 12 are guided over breast rollers 16, 18, these breast rollers in FIGS. 2 and 3 being designed as open forming rollers 16 ', around which both sieves are brought together at a certain angle, including the fiber suspension.
  • a headbox nozzle 20 In front of the stock inlet gap is a headbox nozzle 20.
  • the headbox takes place vertically downwards via this nozzle 20, in FIG. 2 from left to top right, likewise in FIG. 3 and in FIG. 4 essentially vertically from bottom to top .
  • the screens 10 and 12 are guided as endless screens over deflecting rollers 22 and 24, respectively.
  • the second sieve 12 is only partially shown in FIGS. 2 and 3.
  • the entire forming zone is divided into two forming sections, namely a first forming section F1 and a second forming section F2, in which the two screens are moved together with the fiber suspension interposed.
  • a first forming section F1 and F2 there is a preferably open forming roller 26, which can also be referred to as the main forming roller.
  • the deflection angle in the exemplary embodiments according to FIG. 1, 2, 3, 4 is approximately 90 °. This requires a corresponding wrap angle alpha of the main forming roller 26.
  • a forming shoe 28 is preferably opposite a row of forming pressure bars 30 (for example four to five).
  • the respective water withdrawal systems are adapted to whether the water is drawn off with or against gravity.
  • the first forming section F1 is in a vertical orientation and the forming section F2 in a horizontal orientation, which in principle can also be the other way round, although the exemplary embodiments shown are of particular advantage.
  • a forming shoe 27 is arranged in the forming pressure bars 30 in the second forming section F2 in the area of the first sieve 10 (transport sieve) and does not necessarily have to be provided with suction drainage.
  • a so-called “top suction device 28" is arranged in front of the forming shoe 28 arranged in the second forming section F2 and resting on the counter-sieve 12.
  • a separating suction device 23 which is designed as a separating roller 21 in FIG. 3, is preferably arranged on the transport screen 10 behind the forming section F2.
  • the formation shoes can be provided with a curved, but also with a straight surface. They can be operated with or without vacuum.
  • the main forming roller can be designed as an open roller, for example such a roller with a grill structure (honeycomb structure) or as a suction roller.

Landscapes

  • Paper (AREA)

Claims (18)

  1. Formeur à double toile pour la fabrication de papier, avec deux toiles filtrantes sans fin (10, 12) circulantes, qui circulent ensemble en formant une fente (14) pour l'introduction de la pâte et sont guidées conjointement dans cet état le long d'une zone de formation, une des toiles étant une toile de transport (10) et l'autre une contre-toile, avec au moins un cylindre formeur sur la périphérie duquel les deux toiles sans fin sont guidées conjointement, au moins un élément formeur stationnaire (28) sur au moins un côté s'applique, dans un premier trajet de formation (F1) situé en amont du cylindre formeur (26) dans le sens de circulation des toiles, sur au moins une des toiles, un deuxième trajet de formation (F2) étant prévu en aval du cylindre formeur (26) dans le sens de circulation des toiles, dans lequel deuxième trajet au moins un autre élément formeur stationnaire (28; 30) sur au moins un côté s'applique sur au moins une des toiles, au moins deux éléments formeurs stationnaires (28,30) étant disposés sensiblement en face l'un de l'autre, caractérisé en ce que le deuxième trajet de formation (F2) est disposé sous un angle d'environ 90° par rapport au premier trajet de formation, et en ce qu'au moins deux éléments formeurs stationnaires (28', 30') se trouvent dans le premier trajet de formation (F1), sensiblement en face l'un de l'autre.
  2. Formeur à double toile selon la revendication 1, caractérisé en ce que la fente (14) d'introduction de la pâte est disposée au-dessus du premier trajet de formation.
  3. Formeur à double toile selon la revendication 1, caractérisé en ce que la fente (14) d'introduction de la pâte est disposée en dessous du premier trajet de formation.
  4. Formeur à double toile selon une des revendications 1 à 3, caractérisé en ce que les éléments formeurs stationnaires sont constitués par un patin (28) ou par au moins une latte formeuse à pression (30).
  5. Formeur à double toile selon une des revendications 1 à 4, caractérisé en ce qu'un cylindre formeur supplémentaire (16) est disposé à la fente (14) d'introduction de la pâte.
  6. Formeur à double toile selon la revendication 1, caractérisé en ce que le deuxième trajet de formation représente au moins 80% de la longueur d'enroulement sur le cylindre formeur (26) situé entre les trajets de formation, est égal à cette longueur et est, en particulier, plus grand que celle-ci.
  7. Formeur à double toile selon la revendication 4, caractérisé en ce qu'au moins quatre à cinq lattes formeuses à pression sont disposées l'une à la suite de l'autre.
  8. Formeur à double toile selon la revendication 1, caractérisé en ce qu'un des éléments formeurs se faisant face est sous la forme d'un patin formeur (28'; 28) avec une surface d'appui courbe ou droite, et que l'autre élément formeur est sous la forme d'au moins une latte formeuse à pression (30'; 30).
  9. Formeur à double toile selon une des revendications 1 à 8, caractérisé en ce que l'élément formeur stationnaire (28) disposé chaque fois au-dessus est sous la forme d'un patin formeur à assèchement par aspiration.
  10. Formeur à double toile selon la revendication 1, caractérisé en ce que, dans le deuxième trajet de formation (F2), un élément séparateur, par exemple sous la forme d'un rouleau séparateur (21) ou d'un dispositif séparateur à aspiration (23) est disposé à la suite de l'élément formeur stationnaire (28), en particulier à la suite d'un patin formeur.
  11. Formeur à double toile selon la revendication 1, caractérisé en ce que, dans le deuxième trajet de formation (F2), un pré-aspirateur (28'') est disposé en amont de l'élément formeur stationnaire (28), en particulier en amont d'un patin formeur, et plus particulièrement en amont d'un patin formeur situé au-dessus.
  12. Formeur à double toile selon la revendication 1, caractérisé en ce que, dans le deuxième trajet de formation (F2), un patin formeur courbe (28'') est disposé en amont d'un élément formeur (28), en particulier, d'un tel élément situé au-dessus et en particulier d'un tel élément sous la forme d'un patin formeur, ledit patin courbe s'appliquant en particulier sur la contre-toile (12).
  13. Formeur à double toile selon la revendication 1, caractérisé en ce que la surface active de l'élément formeur stationnaire se trouve dans la zone entre le sommet supérieur et le sommet inférieur du cylindre formeur (26) se trouvant entre les trajets de formation (F1, F2).
  14. Formeur à double toile selon la revendication 8, caractérisé en ce que le trajet partiel de formation (F3) sollicité des deux côtés est plus court que la longueur d'enroulement sur le cylindre formeur principal (26) situé entre les trajets de formation (F1, F2).
  15. Formeur à double toile selon la revendication 1, caractérisé en ce que la longueur de toile en contact avec le patin formeur dans le premier trajet de formation (F1) est plus courte que la longueur d'enroulement sur le cylindre formeur (26) se trouvant entre les deux trajets de formation (F1, F2).
  16. Formeur à double toile selon une des revendications 1 à 15, caractérisé en ce que le cylindre formeur (26) se trouvant entre les deux trajets de formation (F1, F2) est sous la forme d'un cylindre ouvert.
  17. Formeur à double toile selon la revendication 16, caractérisé en ce que le cylindre formeur ouvert (26) est un cylindre avec une structure ouverte à grille ou en nid d'abeille.
  18. Formeur à double toile selon la revendication 17, caractérisé en ce que le cylindre formeur ouvert est un cylindre aspirant.
EP91121320A 1991-01-24 1991-12-12 Formeur à double toile Expired - Lifetime EP0496073B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4102065A DE4102065C2 (de) 1991-01-24 1991-01-24 Doppelsiebformer
DE4102065 1991-01-24

Publications (2)

Publication Number Publication Date
EP0496073A1 EP0496073A1 (fr) 1992-07-29
EP0496073B1 true EP0496073B1 (fr) 1995-04-05

Family

ID=6423626

Family Applications (1)

Application Number Title Priority Date Filing Date
EP91121320A Expired - Lifetime EP0496073B1 (fr) 1991-01-24 1991-12-12 Formeur à double toile

Country Status (5)

Country Link
US (1) US5259929A (fr)
EP (1) EP0496073B1 (fr)
AT (1) ATE120817T1 (fr)
CA (1) CA2059946C (fr)
DE (1) DE4102065C2 (fr)

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4301103C1 (de) * 1993-01-18 1994-08-18 Voith Gmbh J M Siebpartie einer Papiermaschine
DE4310540C2 (de) * 1993-03-31 1997-06-12 Voith Sulzer Papiermasch Gmbh Leistenformer
SE501332C2 (sv) * 1993-05-27 1995-01-16 Valmet Karlstad Ab Sätt att forma en tissuepappersbana
JP3244911B2 (ja) * 1994-01-28 2002-01-07 三菱重工業株式会社 抄紙機のツインワイヤフォーマ
DE4420801C2 (de) * 1994-06-16 1997-01-30 Voith Gmbh J M Verfahren zum Betreiben einer Doppelsiebzone einer Papiermaschine zur Herstellung von Faserstoffbahnen sowie Siebzone hierzu
FI96623C (fi) * 1994-08-31 1996-07-25 Valmet Paper Machinery Inc Kaksiviiraformeri, etenkin nopeille paperikoneille
DE19530983B4 (de) * 1995-08-23 2006-04-27 Voith Paper Patent Gmbh Vorrichtung zum Herstellen eines mehrlagigen Papiers oder Kartons
US5736011A (en) * 1996-07-17 1998-04-07 Voith Sulzer Paper Technology North America, Inc. Wet end assembly for a paper making machine
DE19651241A1 (de) * 1996-12-10 1998-06-18 Voith Sulzer Papiermasch Gmbh Doppelsieb-Blattbildungseinrichtung
AT405538B (de) 1997-11-28 1999-09-27 Andritz Patentverwaltung Vorrichtung zum entwässern einer faserstoffbahn
DE19803591A1 (de) * 1998-01-30 1999-08-05 Voith Sulzer Papiertech Patent Doppelsieb-Former
US6372091B2 (en) 1999-06-18 2002-04-16 Metso Paper, Inc. Method and apparatus for forming a paper web
DE19943369A1 (de) * 1999-09-10 2001-03-22 Voith Paper Patent Gmbh Doppelsiebformer
DE10009362A1 (de) * 2000-02-29 2001-08-30 Voith Paper Patent Gmbh Doppelsiebformer
DE10106731A1 (de) * 2001-02-14 2002-08-22 Voith Paper Patent Gmbh Doppelsiebformer zur Herstellung einer Faserstoffbahn aus einer Faserstoffsuspension
DE10116364A1 (de) * 2001-04-02 2002-10-10 Voith Paper Patent Gmbh Saugelement
DE10335362A1 (de) * 2003-08-01 2005-02-17 Voith Paper Patent Gmbh Doppelsiebformer
FI116628B (fi) * 2004-02-13 2006-01-13 Metso Paper Inc Monikerrosrainan muodostusosa
FI116688B (fi) * 2004-02-13 2006-01-31 Metso Paper Inc Monikerrosrainan muodostusosa
WO2013160527A1 (fr) * 2012-04-27 2013-10-31 Metso Paper, Inc. Section de formation

Family Cites Families (14)

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Publication number Priority date Publication date Assignee Title
GB1288277A (fr) * 1969-02-03 1972-09-06
DE2102717A1 (de) * 1970-01-26 1971-08-12 Enso Gutzeit Oy Verfahren und Vorrichtung zur Herstellung von Papier, Karton oder einer ähnlichen Fasermaterialbahn
US4125428A (en) * 1977-06-27 1978-11-14 The Black Clawson Company Vertical twin wire paper machine
AT379622B (de) * 1980-11-26 1986-02-10 Escher Wyss Gmbh Papiermaschine mit zwei beweglichen wasserdurchlaessigen entwaesserungsbaendern, z.b. sieben
DE3153305C2 (de) * 1981-09-04 1986-10-23 Sulzer-Escher Wyss GmbH, 7980 Ravensburg Entwässerungseinheit für Langsieb-Papiermaschinen
FI851035L (fi) * 1984-05-03 1985-11-04 Beloit Corp Oevre formningsvira i en pappersmaskin.
FI862809A (fi) * 1986-07-02 1988-01-03 Ahlstroem Oy Stoedande av en avvattningsenhet pao pappersmaskinens formningsdel.
US4790909A (en) * 1986-12-17 1988-12-13 Beloit Corporation Two-wire paper forming apparatus
GB8710428D0 (en) * 1987-05-01 1987-06-03 Beloit Corp Multi-ply web forming apparatus
DE3815470A1 (de) * 1988-05-06 1989-11-16 Voith Gmbh J M Doppelsieb-former
FI84734C (fi) * 1988-05-23 1992-01-10 Valmet Paper Machinery Inc Dubbelviraformare foer pappersmaskin.
JPH02133689A (ja) * 1988-11-14 1990-05-22 Mitsubishi Heavy Ind Ltd 抄紙機ツインワイヤホーマ
FI885607A (fi) * 1988-12-01 1990-06-02 Ahlstroem Valmet Anordning foer styrning av viror i en pappersmaskins former.
FI98540C (fi) * 1989-05-08 1997-07-10 Valmet Corp Laite paperi- tai kartonkirainan muodostamiseksi kuitumateriaalista

Also Published As

Publication number Publication date
US5259929A (en) 1993-11-09
CA2059946C (fr) 1996-08-20
DE4102065A1 (de) 1992-07-30
ATE120817T1 (de) 1995-04-15
EP0496073A1 (fr) 1992-07-29
DE4102065C2 (de) 1996-02-01

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