EP0567484B1 - Procede et dispositif relatifs a la presse d'une machine a papier et servant a detacher la bande de la face d'un cylindre de pression - Google Patents

Procede et dispositif relatifs a la presse d'une machine a papier et servant a detacher la bande de la face d'un cylindre de pression Download PDF

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Publication number
EP0567484B1
EP0567484B1 EP92902194A EP92902194A EP0567484B1 EP 0567484 B1 EP0567484 B1 EP 0567484B1 EP 92902194 A EP92902194 A EP 92902194A EP 92902194 A EP92902194 A EP 92902194A EP 0567484 B1 EP0567484 B1 EP 0567484B1
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EP
European Patent Office
Prior art keywords
transfer
web
roll
press
suction
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
EP92902194A
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German (de)
English (en)
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EP0567484A1 (fr
Inventor
Juhani Niskanen
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Valmet Technologies Oy
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Valmet Oy
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Publication of EP0567484A1 publication Critical patent/EP0567484A1/fr
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Expired - Lifetime legal-status Critical Current

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    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F3/00—Press section of machines for making continuous webs of paper
    • D21F3/02—Wet presses
    • D21F3/0281—Wet presses in combination with a dryer roll
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
    • D21F3/00—Press section of machines for making continuous webs of paper
    • D21F3/02—Wet presses
    • D21F3/04—Arrangements thereof

Definitions

  • the invention concerns a method for detaching a web from the smooth mantle face of a press roll in the press section of a paper machine in the press section of a paper machine according to the preamble of claim 1.
  • the invention concerns a press section of a paper machine according to the preamble of claim 7.
  • the first twin-wire nip is formed between a holler-faced lower press roll and an upper press-suction roll.
  • Said suction roll forms the second nip with the smooth-faced centre roll of the press, and the third press nip is formed in connection with said centre roll.
  • this press section may include a separate nip, as a rule a fourth nip in the press, after which the web is transferred to the drying section.
  • the first twin-felt horizontal nip is formed between a lower hollow-faced roll and an upper press-suction roll, after which the web follows the upper fabric as a vertical run into the second nip, which is formed between a hollow-faced roll separate from the rolls in the first nip and the smooth-faced centre roll.
  • a third press nip which is provided with a felt, is formed by means of a hollow-faced press roll.
  • the web is detached from the smooth face of the centre roll in the press by means of a pulling force parallel to the running direction of the web as a free unsupported draw.
  • This free draw is quite critical in view of the operation of a paper machine.
  • a speed difference is employed which stretches the web, which results in certain drawbacks.
  • said unsupported draw forms a problematic point susceptible of breaks in the paper machine.
  • the negative pressure applied to the web in the suction zone of the transfer- suction roll produces a corresponding negative pressure between the web and the smooth face of the centre roll, which has the consequence that the web is not detached but follows the smooth face of the centre roll.
  • the wet breaking strength of newsprint is F M ⁇ 200 N/m, and the corresponding grammage is 42 g/m 2 , and the moisture content in the first free gap in the nip is ⁇ 42 %.
  • the web must be made generally stronger or more homogeneous (no weak points), or the free gaps must be eliminated.
  • the present invention endeavours to solve said problems by means of elimination of the free gaps.
  • the general object of the present invention is to provide novel means in the detaching of the web from the centre roll or equivalent in the press section and in the transfer of the web into a separate nip or to the drying section.
  • the object of the present invention is to provide a method and a device for detaching the web from a smooth-faced press roll wherein the web need not be stretched, i.e. it is unnecessary to employ so-called draw and speed difference.
  • the object of the invention is to provide a press section in which, when necessary, it is possible to use a fully closed draw when the web is transferred from the centre roll or from a corresponding other roll in the press to the drying section, as a rule onto its drying wire, or onto the press fabric of a separate nip.
  • press section of the invention is characterized by the features of the characterizing clause of claim 7.
  • Figure 1 is a schematic side view of the environment of application of the invention and of a first embodiment of the invention, in which the press fabric of the third nip is used as the transfer fabric in the transfer from the centre roll.
  • Figure 2 shows, in a way corresponding to Fig. 1, an embodiment of the invention in which a separate transfer fabric is used that runs around the transfer-suction roll.
  • Figure 3 is a vertical sectional view in the machine direction of a transfer nip in accordance with the invention as accomplished by means of a transfer-suction roll.
  • Figure 4 shows an exemplifying embodiment of the invention in which the suction transfer takes place by means of a static transfer-suction box that comprises two parts.
  • Figures 1 and 2 are schematic illustrations of a press section of a paper machine, in which the paper web W, which comes from the forming wire 10 of the former, is dewatered by pressing.
  • the web W is transferred from the wire 10 at the pick-up point P by means of the press felt 12 on the suction zone 11a of the pick-up roll 11.
  • the web W is transferred into the first dewatering nip N 1 , which is formed between the press-suction roll 16 and the hollow-faced 14' lower press roll 14.
  • the first nip N 1 is a two-felt nip, and it includes a lower felt 13 guided by the guide rolls 15.
  • Figs. 1 and 2 the press rolls 14,16,18, and 21 form a compact combination of rolls in which there are three subsequent nips N 1 ,N 2 ,N 3 , through which the web W runs as a closed draw, being constantly supported by a felt or roll face.
  • a fourth, separate nip N 4 is formed between a smooth-faced 30', large-diameter press roll 30 and a lower hollow-faced 31' press roll 31. After the fourth nip N 4 , the web W follows the smooth face 30', from which it is detached on the guide roll 39, being transferred onto the drying wire 36 of the drying section, which is guided by the guide roll 35.
  • the web W is made to adhere to the drying wire 36 by means of a suction box 37, being passed on the wire 36 into a multi-cylinder dryer (not shown).
  • a suction box 37 On the upper sector of the upper press roll 30 of the separate nip N 4 , there are jet means 29 followed by a doctor 28, which keeps the roll face 30' clean.
  • the press fabric 26 is separated from the web W by means of the guide roll 38, being passed back into connection with the web W into the transfer nip 30/39 over the transfer-suction roll 39.
  • the web W is detached from the roll face 30', and the web W is transferred over the roll 39 on the press fabric 26, being secured by the negative pressure in the suction zone 39b.
  • the web W is detached from the fabric 26 by means of the suction box 37 and is transferred onto the drying wire 36. Differing from the above, in Fig.
  • the press fabric 26, being guided by the guide roll 32b, is separated from the web W, which is transferred on the roll face 30' onto the suction zone 39a of the transfer-suction roll 30.
  • a particular transfer fabric 46 is passed, on which the web W is transferred onto the drying wire 36, being secured by the second suction zone 39b of the roll 39.
  • first steam supply box 17 On the suction sector 16a between the first and the second nip, there is a first steam supply box 17. In a corresponding way, between the second and third nip N 2 and N 3 , there is a second steam supply box 20 operating against the web W.
  • second steam supply box 20 By means of the hot steam fed out of the boxes 17 and 20, it is also possible to affect the elastic properties of the fibres in the web and the viscosity and the surface tension of the water present in the web so that the dewatering is intensified in the nips N 2 and N 3 .
  • the temperature T of the web W and of the face 18' of the centre roll 18 is raised to such a level that the detaching of the web W and its transfer from the roll face 18' can be carried out successfully in the transfer nip N S .
  • the raising of the temperature level T of the web W takes place by means of internal heating of the centre roll 18, an example of which is given in Fig. 4 by the axial bores 18b made into the roll mantle 18a, into which bores a heating medium, such as hot water or steam, is passed.
  • the roll mantle 18a may be heated by means of the steam boxes 17 and 20, in particular by means of the steam box 20, and also by means of various electric heaters, of which an induction heater 60 is shown as an example in Fig. 2.
  • the press construction described above is substantially known in prior art, and it is described above just as a background and as an environment of application for the present invention.
  • the web W follows the smooth face 18' of the centre roll 18, from which it is detached as a fully closed draw in accordance with the invention by means of a transfer-suction roll 40 provided with a drive or by means of a transfer-suction box 50 (Fig. 4).
  • a transfer-suction roll 40 provided with a drive or by means of a transfer-suction box 50 (Fig. 4).
  • the suction zones 40a,40b of the transfer-suction roll 40 the web W is transferred on the suction zone 25a of the second lower transfer-suction roll 25 onto the press felt 26, which carries the web W on its upper face into the fourth, separate nip N 4 in the press section.
  • the press felt 23 of the third nip N 3 is passed after the nip N 3 onto the guide roll 22a and from it into the transfer nip N S so that said press felt 23 operates as a transfer fabric, which runs around the transfer-suction roll 40 and on which the web W is transferred on the suction zone 25a of the second transfer-suction roll 25 onto the lower fabric 26 of the fourth press nip N 4 .
  • a transfer fabric 44 of its own is arranged to run around the transfer-suction roll 40. which fabric 44 is passed into the transfer nip N S and separated from the transfer-suction roll 40 so that the web W follows the lower fabric 26 of the fourth press nip N 4 . Said transfer is secured, e.g., by means of choice of the surface properties of the fabrics 26 and 44 and possibly by means of the suction box 33.
  • guide rolls and conditioning devices known per se, not shown in Fig. 2.
  • the transfer of the web W from the smooth face of the centre roll 18 takes place as a fully closed draw on the transfer-suction roll 40 aided by the negative pressure present in its interior and effective on the suction zone 40a.
  • the suction zone 40a is followed by the second suction zone 40b of the transfer-suction roll 40, on which the level of negative pressure is lower than that on the zone 40a, ensuring that the web W remains on support of the transfer fabric 23;44.
  • Fig. 3 shows the environment of the transfer nip N S between the centre roll 18 and the transfer-suction roll 40.
  • the transfer-suction roll 40 includes a perforated 42 roll mantle 41, in whose interior there are suction boxes.
  • Fig. 3 in respect of the suction boxes, just the sealing ribs 43 of the first suction zone 40a are shown, which operate against the smooth inner face 41' of the roll mantle 41.
  • the paper web W enters into the transfer nip N S on the smooth face 18' of the centre roll 18.
  • the paper web W adheres tightly to the face 18' by the intermediate of a non-unified water film.
  • the temperature T of the face 18' and of the web W and of the water film that makes the web adhere to the face 18' has been raised to such a level that the water present between the roll face 18' and the web W and partly in the structure of the web W is vaporized as its volume is increased in the transfer nip N S when the web W is sucked towards the transfer fabric 44 by means of the negative pressure p O in the suction zone 40a of the roll 40.
  • the maximum negative pressure that can arise here is the pressure p S of saturated vapour prevailing at said temperature T.
  • a negative pressure can be sucked between the paper web W and the transfer fabric 44, the absolute value of said negative pressure being p O ⁇ p S .
  • the length of the transfer nip N S has been dimensioned such that there is time enough for generation of full negative pressure between the paper web W and the transfer fabric 44.
  • the outer face of the mantle 41 of the transfer-suction roll 40 may be provided with a soft coating, by whose means the length of the transfer nip N S can be extended to make it large enough.
  • the reference S denotes the point or line at which the paper web W is separated from the face 18', because in the gap A that is opened, no higher negative pressure can arise than the pressure p S of saturated water vapour corresponding to the temperature T.
  • the temperature T of the face 18' of the centre roll 18 and of the web when they enter into the transfer nip N S is in the invention, as a rule, in the range of T ⁇ 50...100°C, which corresponds to the range of pressure of saturated water vapour (absolute values) of p S ⁇ 0.13...1.0 bar.
  • a temperature range that is particularly favourable and practical in view of the objectives of the invention is the range T ⁇ 65...75°C, which corresponds to the range of pressure of water vapour of p S ⁇ 0.25...0.40 bar.
  • Fig. 4 shows an embodiment of the invention in which a static suction box 50 is employed instead of a revolving suction roll 40.
  • a static suction box 50 Inside the suction box 50, two suction chambers 50a and 50b are fitted, whose open ends are defined by horizontal sealing ribs 53, over which the transfer fabric 44 is passed.
  • p O prevails that in the transfer nip N S the web W is separated from the roll face 18' as a closed draw.
  • the second suction zone 50b there is a lower level of negative pressure (as a rule in a range of p I ⁇ 0.1 bar), whereby it is ensured that the web W follows the transfer fabric 44.
  • the suction chambers 50a and 50b communicate with the suction ducts 55a and 55b of the suction box 50 by the intermediate of the pipes 54a and 54b.
  • the suction box 50 the web W is transferred on the transfer fabric 55 into a transfer nip formed by the rolls 32 and 45, after which the web W is separated from the transfer fabric 44 and is transferred onto the support of the press felt 26, to which it is made to adhere by means of the negative pressure in the suction box 33.
  • Said temperature level T of the web W and the roll face 18' that enter into the transfer nip N S is regulated to a level suitable in view of the invention by means of internal heating systems 18b in the roll 18 or by means of steam boxes 17 and/or 20.
  • the internal heating systems in the roll 18 may also include heating media passed into the interior of the roll mantle 18a, such as steam or hot water.
  • a heater placed before the transfer nip N S preferably an induction heater 60, by whose means the temperature T of the roll face 18' is raised to a level suitable in view of the suction transfer and the closed draw of the web W in accordance with the invention.
  • the induction heater 60 is connected with a unit 61 for the supply of electric power. If necessary, the induction heater 60 and the other heaters may also be arranged so that, by its means, the transverse temperature profile of the roll face 18' and the web W before the transfer nip N S and in the nip area is controlled so that said profile is optimal in view of the transfer of the web W, as a rule as uniform as possible, e.g., in view of the different properties of adhesion to the roll face 18' possessed by different pulp qualities.
  • the invention can also be applied to a press section in which there is no separate nip N 4 , but the web W is transferred as a closed draw from the fabric that runs over the transfer-suction roll 40 into the drying section, e.g. onto its drying wire, so that the press fabric 26 shown in Figs. 1 and 2 corresponds to the drying wire in the first wire group, on which fabric the web W is passed as a single-wire draw through the first drying group.
  • Figs. 1 and 2 show such a "Sym-Press-II” press section in which the suction roll 16 forms two nips N 1 and N 2 .
  • the invention can also be applied to other press geometries, such as the applicant's "Sym-Press-O" press section, in which, after the press-suction roll 16, the web W has a vertical draw supported by the fabric 12 and, in stead of the press-suction roll 16, there is a separate press roll in connection with the centre roll 18.
  • the negative pressure that prevails in the suction zone 40a,50a of the suction roll 40 or of the suction box 50 is exactly equal to the vapour pressure corresponding to the temperature T of the roll face 18 or of the web W, but in some special situations a lower level of negative pressure may also be adequate, which level is, however, chosen such that it substantially promotes the detaching of the web W without a detrimentally high pulling tension applied to the web. This is the case, e.g., with thicker paper qualities and/or with stronger pulps.

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  • Paper (AREA)
  • Replacement Of Web Rolls (AREA)

Claims (10)

  1. Procédé pour détacher une bande (W) de la surface lisse (18') de la chemise d'un rouleau presseur (18) dans la presse d'une machine à papier, dans lequel procédé est employée une zone de transfert (40a, 50a) sur laquelle une toile de pressage (23) ou une toile de transfert particulière (44) est amenée à passer de façon à réaliser un "détachement fermé de la bande (W), ladite zone de transfert (40a, 50a) ainsi que ladite toile (23, 44) étant agencés pour former avec ladite surface (18') de rouleau un interstice de pincement de transfert (NS), et dans lequel procédé, dans la zone de transfert, le niveau de température (T) de ladite surface (18') de rouleau et/ou de la bande (W) est établi ou réglé suffisamment haut pour que l'eau présente entre la bande (W) et la surface (18') de rouleau et partiellement dans la structure de la bande (W) s'évapore,
       caractérisé en ce qu'on utilise comme zone de transfert une zone (40a, 50a) de transfert par aspiration dans laquelle on fait régner une pression absolue (pO) inférieure à la pression atmosphérique et en ce qu'au point de transfert le niveau (T) de la température de ladite surface (18') de rouleau et/ou de la bande (W) est établi ou réglé suffisamment haut pour que la pression absolue (pS) de vapeur saturée de l'eau qui correspond audit niveau de température (T) soit également aussi forte ou plus forte que que la pression absolue (pO) que l'on a fait régner dans ladite zone (40a, 50a) de transfert par aspiration.
  2. Procédé selon la revendication 1, caractérisé en ce que le niveau de la pression subatmosphérique (pO) dans ladite zone (40a, 50a) de transfert par aspiration est choisi de façon à être au moins égal à environ 80% de la pression (pS) de vapeur d'eau saturée correspondant à la température (T) de ladite surface (18') de rouleau ou de la bande (W) à transférer.
  3. Procédé selon l'une quelconque des revendications 1 ou 2, caractérisé en ce que dans le procédé est employé un rouleau (40) de transfert par aspiration sur lequel la toile de pressage (23) de l'interstice de pincements précédent (N3) dans la presse ou une toile de transfert (44) indépendante est amenée a passer, et en ce que ledit rouleau (40) de transfert par aspiration est agencé pour former un interstice de pincement (NS) de transfert avec la surface lisse (18') de rouleau depuis laquelle la bande (W) est transférée par "tirage fermé", sans grande différence de traction ou de vitesse.
  4. Procédé selon l'une quelconque des revendications 1 ou 2, caractérisé en ce que dans le procédé est employée une caisse (50) de transfert statique par aspiration dont la zone (50a) ou les zones (50a, 50b) d'aspiration est/sont agencée(s) pour former une zone de transfert de bande (W) fermée en liaison avec la surface lisse (18') de rouleau.
  5. Procédé selon l'une quelconque des revendications 1 à 4, caractérisé en ce que le niveau de température T de ladite surface (18') de rouleau, de laquelle la bande (W) est détachée par "tirage fermé" sans forte traction, est établi ou réglé à une valeur de l'ordre de 65 à 75° C, et en ce que la pression absolue pO dans ladite zone de transfert par aspiration est réglée ou établie à une valeur de l'ordre de 0,25 à 0,4 bar.
  6. Procédé selon l'une quelconque des revendications 1 à 5, caractérisé en ce que, dans le procédé, la bande (W), qui a été transférée depuis la surface lisse (18') de rouleau sur la toile de pressage (23) ou sur le toile de transfert particulière (44), est transportée par " tirage fermé" jusqu'à un interstice de pincement de transfert ou équivalent suivant, depuis lequel la bande (W) est transférée sur une toile de pressage (26) d'un interstice de pincement de pressage séparé (N4) dans la presse ou sur la toile de séchage (36) de la section de séchage.
  7. Presse de machine à papier, comprenant un agencement de rouleaux presseurs (14, 16, 18, 21), qui forment les uns avec les autres un ou plusieurs interstices de pincement de pressage (N1, N2, N3), un de ces rouleaux étant un rouleau (18) à surface lisse depuis lequel une bande (W) est détachée à l'aide d'un dispositif de transfert (40, 50) et est transférée en outre jusqu'à la section de séchage de la machine à papier ou jusque dans un interstice de pincement de pressage séparé (N4) dans la presse, ledit dispositif de transfert (40, 50) étant agencé pour former un interstice de pincement de transfert (NS), qui réalise un "tirage fermé" de la bande (W), en liaison avec la surface lisse (18') de rouleau, ladite presse comportant en outre un dispositif ou des dispositifs chauffant(s) (20, 60) à l'aide desquels la température (T) de la bande qui pénètre au point de transfert et/ou la température de ladite surface lisse (18') de rouleau augmente jusqu'à un niveau suffisamment élevé pour que l'eau présente entre la bande (W) et la surface lisse (18') de rouleau et partiellement dans la structure de la bande (W) s'évapore, caractérisée en ce que le dispositif de transfert est un rouleau rotatif (40) de transfert par aspiration ou une caisse équivalente (50) de transfert statique par aspiration, ledit rouleau rotatif (40) de transfert par aspiration ou le caisse équivalente (50) de transfert statique par aspiration étant pourvu d'une zone d'aspiration (40a, 50a) au niveau de l'interstice de pincement de transfert (NS) dans lequel une pression absolue (pO) inférieure à la pression atmosphérique est établie et en ce que le dispositif ou les dispositifs chauffant(s) (20, 60) élèvent la température (T) de la bande (W) qui pénètre au point de transfert et/ou la température de ladite surface lisse (18') de rouleau jusqu'à un niveau suffisamment haut pour que la pression absolue (pS) de vapeur saturée de l'eau qui correspond audit niveau de température soit aussi forte ou plus forte que la pression absolue (pO) qui règne dans ladite zone d'aspiration (40a, 50a).
  8. Presse de machine à papier selon la revendication 7, caractérisée en ce que le dispositif de transfert par aspiration est un rouleau (40) de transfert par aspiration, dans lequel, au niveau de l'interstice de pincement de transfert (NS), se trouve une zone d'aspiration (40a) suivie par une seconde zone d'aspiration (40b), de préférence à une pression subatmosphérique inférieure, et en ce qu'une toile de pressage (23) de l'interstice de pincement de pressage précédent (N3) ou une toile de transfert particulière (44) est amenée à passer par ledit interstice de pincement de transfert (NS).
  9. Presse de machine à papier selon la revendication 7 ou 8, caractérisée en ce que, dans ledit rouleau (18) à surface lisse, qui est de préférence le rouleau central d'une presse compacte et fermée, se trouve un dispositif de chauffage interne (18b), et/ou une boite (20) à vapeur et/ou un chauffage par induction (60) ou équivalent disposé en liaison avec ledit rouleau (18), grâce à quoi le niveau de la température (T) de la surface (18') du rouleau peut être porté suffisamment haut pour le transfert par aspiration "fermée" de la bande (W).
  10. Presse de machine à papier selon l'une quelconque des revendications 7 à 9, caractérisée en ce que, après ledit rouleau (40) de transfert par aspiration ou ladite caisse (50) de transfert statique par aspiration, la bande (W) est amenée a passer sur une toile (23, 44) jusqu'à un interstice de pincement de transfert additionnel ou équivalent, grâce à quoi la bande (W) est transférée sur la toile inférieure (26) d'un interstice de pincement de pressage séparé (N4) dans la presse ou sur une toile de séchage (36) de la section de séchage de la machine à papier ou sur quelque autre toile équivalente.
EP92902194A 1991-01-18 1992-01-20 Procede et dispositif relatifs a la presse d'une machine a papier et servant a detacher la bande de la face d'un cylindre de pression Expired - Lifetime EP0567484B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FI910288A FI92941C (fi) 1991-01-18 1991-01-18 Menetelmä ja laite paperikoneen puristinosalla rainan irrottamiseksi puristintelan pinnalta
FI910288 1991-01-18
PCT/FI1992/000014 WO1992013133A1 (fr) 1991-01-18 1992-01-20 Procede et dispositif relatifs a la presse d'une machine a papier et servant a detacher la bande de la face d'un cylindre de pression

Publications (2)

Publication Number Publication Date
EP0567484A1 EP0567484A1 (fr) 1993-11-03
EP0567484B1 true EP0567484B1 (fr) 1997-07-23

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EP92902194A Expired - Lifetime EP0567484B1 (fr) 1991-01-18 1992-01-20 Procede et dispositif relatifs a la presse d'une machine a papier et servant a detacher la bande de la face d'un cylindre de pression

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EP (1) EP0567484B1 (fr)
AT (1) ATE155837T1 (fr)
CA (1) CA2099379C (fr)
DE (1) DE69221123T2 (fr)
FI (1) FI92941C (fr)
WO (1) WO1992013133A1 (fr)

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DE4322644C1 (de) * 1993-07-07 1994-09-29 Billhofer Maschf Gmbh Vorrichtung zum Auftragen wachshaltiger Dispersionen
DE4427281A1 (de) * 1994-08-02 1996-02-08 Voith Gmbh J M Verfahren zum Einfädeln einer Faserstoff-Bahn, insbesondere in eine Papierherstellungsmaschine
DE19741517A1 (de) * 1997-09-20 1999-03-25 Voith Sulzer Papiermasch Gmbh Verfahren zur Verringerung der Haftung einer feuchten Faserstoffbahn an einer rotierenden Walze
FI117981B (fi) * 2002-12-20 2007-05-15 Upm Kymmene Corp Paperikoneen tai vastaavan nippijärjestely
FI120239B (fi) 2008-06-19 2009-08-14 Metso Paper Inc Rainanmuodostuskone ja menetelmä rainanmuodostuskoneessa

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FI75890C (fi) * 1987-01-23 1988-08-08 Valmet Paperikoneet Oy Foerfarande och anordning i presspartiet i en pappersmaskin foer loesgoering av banan fraon ytan av en pressvals.
FI89085C (fi) * 1987-01-23 1993-08-10 Valmet Paperikoneet Oy Regleringsfoerfarande foer en pappersmaskins pressparti
FI83895C (fi) * 1988-04-13 1991-09-10 Valmet Paper Machinery Inc Foerfarande och anordning vid pressbehandling av en pappersbana.

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Publication number Publication date
EP0567484A1 (fr) 1993-11-03
WO1992013133A1 (fr) 1992-08-06
FI910288A0 (fi) 1991-01-18
FI92941C (fi) 1995-01-25
CA2099379C (fr) 2000-04-25
FI92941B (fi) 1994-10-14
ATE155837T1 (de) 1997-08-15
DE69221123D1 (de) 1997-08-28
CA2099379A1 (fr) 1992-07-19
DE69221123T2 (de) 1997-11-20
FI910288A (fi) 1992-07-19

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