FI117981B - Pinching arrangement for a paper machine or the like - Google Patents

Description

117981

BACKGROUND OF THE INVENTION The present invention relates to a nip arrangement on a paper or board machine or a paper or board finishing machine, the nip arrangement 5 comprising: belt rotation as in the first nip, and 10 - the first roll and the third roll remain within the same belt rotation, and - the web to be treated is in contact with one side of the surface of the second roll and the other side with the belt thread; an arrangement for transferring the web from the surface of the second roll to the surface of the belt pass.

EP 0770727 discloses an arrangement in which two belt turns pass through a nip between which a paper web is advanced. The paper web 20 is guided by a suction acting through the belt, which can be provided with a suction roll.

• · · • · ·:: * The problem with known solutions is e.g. the number of belt turns and • · that when transported between the belts, an uneven surface corresponding to the surface structure of the 25 belts is formed.

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By means of a nip arrangement according to the invention, the aforementioned problems £ *: can be avoided. The nip arrangement according to the invention is characterized in that the arrangement for transferring the web from the surface of the second roll to the surface of the belt rotation comprises ♦. ♦ ··. - a third roll which is a suction roll or / *.

In the nip arrangement according to the invention, the number of belts may be reduced. * ···. *. The surface of the web to be treated can be wet-calendered * m smooth. Reliable closed exports are also achieved on the web.

2 117981

The nip arrangement comprises a first and a second nip. The first and second nip passes the same belt rotation which carries the web to be treated with it. The first nip is formed between the first roll 5 and the second roll, and the web to be treated is in contact with the surface of the second roll. The second nip is formed between the second roll and the third roll, i.e., in both the first and second nip, the second nip forming surface is a second roll. The second nip may not be loaded, but the third roll is in contact with the belt, the 10 belt is in contact with the web being processed, and the web is in contact with the other roll. The press portion in the first nip dehydrates and in the second nipple the web is transferred from a smooth roll according to the belt.

As the web to be processed passes through the first nip, the surface in contact with the roll surface becomes smooth, i.e. the surface is wet calendered. The third roll may be provided with a drive, whereby at one nip a local speed difference may be provided to stretch and release the web from the surface of the other roll. The third roll 20 may be a suction roll, whereby the suction acting through the belt pass after the second nip easily moves the web to the surface of the belt, and the web being processed does not continue. on the surface of another roll. This results in a secure * · [closed web export, which prevents the web from breaking easily. The separation of the web from the second roll after the second nip can be suitably enhanced

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25 or with a suitable scraper.

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The nip arrangement according to the invention is advantageous on the press section of a paper or board machine, whereby the strength level of the paper or board is still low. It is particularly advantageous to use the invention in the manufacture of various types of printing papers, such as SC paper. * · *. during manufacture. The principle of the invention can be used. for example, when drying paper with a drying section and • · · * · * · calendering.

35 Because of the conditions of use described above, belts are used to mean:. in this context, blankets, wires, belt calender belts or the like, which can be used to form a forward moving part (belt rotation) of the papermaking machine 117981 '3. On the press section, the strap is generally a press felt.

The first and second rolls may be heated or unheated. They can be hard or flexible. Types of rollers include conventional rollers or shoe rolls. In the case of the press section, usually the first roll is a shoe roll or other common press-water-removing press roll, for example a grooved roll. The second roll is generally a smooth roll 10, for example a ceramic roll, a synthetic roll coated smooth roll, or a stone roll. The third roll is preferably a suction roll.

The invention will now be described with reference to the accompanying drawings, in which Figures 1-4 illustrate certain embodiments of the invention.

Figure 1 shows a basic concept of a nip arrangement according to the invention. The first roll 1 is a shoe roll and the second roll 2 is a ceramic roll. The belt 5 is formed by belt auxiliary rollers 20. The belt 5 extends from the first nip N1 between the first and second rolls so that it contacts the TV of the first roll 1. surface and the web to be processed touches the 2 surfaces of another roll. Another roll. A second nip N2 is formed between the 2 and the third roll 3, through which the belt 5 and the web continue to pass. The third roll 3 may be a suction roll, *. which facilitates the transfer of the web from the surface of the second roll 2 to the surface of the belt 5 '[. The third roll 3 may be provided with a drive, whereby a local velocity difference may be created between the surfaces of the belt 5 '' f, which stretches the web. The web is wet calendered flat against one roll 2. In order to move the web away from the surface of the belt 5 and further according to the next belt rotation · * · .. 30 11, a suction roll 4 may be provided in the next belt rotation.

»« · • * • · * · «. Figures 2 to 4 show similar nip arrangements as in Fig. *. *. / 1. The web is introduced into the first nip on the surface of the roll 2, where it is displaced from the surface of the transfer belt 9. The web continues to pass through belt 5: ^ 5 to the surface of transfer belt 11 and further to the surface of transfer belt 12, except: ***. 4 where the paper web is introduced into nipple N1 directly on the surface of the transfer belt 5 * · ·. The rolls 6, 7 and 8 are arranged such that after passing through nipples 117981 4 therebetween, the web is treated on both sides in accordance with the principle of the invention. The moisture content converter 10 of the transfer belt may be, for example, a suction box.

The invention is not limited to the foregoing, but may vary within the scope of the claims.

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Claims (2)

1. Nippijärjestely paperi- tai kartonkikoneella tai paperin tai kartongin jälkikäsittely konwella, joka nippijärjestely käsittää 5 - one-to-one nipin (N1), jossa ensimmäisen telan (1) ja toisen telan (2) velistä kulkee hihnakierto (5) ), jossa toisen telan (2) yes coalman telan (3) velistä kulkee same hihnakierto (5) kuin ensimmäisessäkin ni-pissä (N1), yes 10. ensimmäinen tela (1) ja kolmas tela (3) jäävät saman hihnakierron ( 5) sisään, yes - käsiteltävä raina on ensimmäisen nipin (N1) ja toisen nipin (N2) velisen matkan kosketuksissa toiselta puoleltaan toisen telan (2) pinnan chance yes toiselta puoleltaan hihnakierron (5) chance, yes 15. toisen nipin on järjestely rainan siirtämiseksi toisen telan (2) pinnalta hihnakierron (5) pinnalle, tunnettu siitä, one järjestely rainan siirtämiseksi toisen telan (2) pinnalta hihnakierron (5) pinnalle käsittää - kolman man telan (3), telan (3), joka on varustettu käytöllä. : \\ 2. Patenttivaatimuksen 1 mukainen nippijärjestely, tunnettu siitä, että]. raina on järjestetty siirrettäväksi hihnakierron (5) pinnalta seuraavan hihnakierron (11) pinnalle suljetulla viennillä. Vs 25 • · 1 '·:! * tl * 1 * · * · ♦ • ·· • · • · • ♦ ** · ·· • · • ·· • ♦ • · ··· * • mi • # 1: • · · * · »» · '♦ · * · * · • 1 · • · · · · • t • · 117981 A nip arrangement in a paper or cardboard machine or in a paper or cardboard finishing machine, comprising a nip arrangement - a first nip (N1), in which a belt circulation (5) runs between a first roll (1) and a second roll ( 2), and - a second nip (N2) in which the same belt circulation (5) as in the first nip (N1) runs between the second roll (2) and a third roll (3), and - the first roll (1) and the third roll (3) are within the same belt circulation (5) and the web to be treated is in contact with the surface of the second nip (N1) and the second nip (N2) on one side the roller (2) and on the other side with the belt circulation (5), and - after the second nip (N2) there is an arrangement for transferring the web from the surface of the second roller (2) to the surface of the belt circulation (5), characterized of, the arrangement for transferring the web from the surface of the second roller (2) to the surface of the belt circulation (5) comprises - a third roller (3) which is a suction roller, or] - a third roller (3) provided with an operation. • · ♦ · »« • · *; Ί 25 A nip arrangement according to claim 1, characterized in that the web is arranged to be transferred from the surface of the belt circulation (5) to the surface of the subsequent belt circulation (11) by closed transmission. ··· • «• · • · • 1 • · · • 1 · • · • · * · 4 * * 1 1 ·· 1 • 1 t · · * · • · • · · ♦ · • ♦ · ♦« «·· ♦ · ♦ ♦ · * · ·