EP3601666B1 - Traitement de bande - Google Patents
Traitement de bande Download PDFInfo
- Publication number
- EP3601666B1 EP3601666B1 EP18702468.2A EP18702468A EP3601666B1 EP 3601666 B1 EP3601666 B1 EP 3601666B1 EP 18702468 A EP18702468 A EP 18702468A EP 3601666 B1 EP3601666 B1 EP 3601666B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- fibrous web
- smoothing
- process according
- web
- cooled
- 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.)
- Active
Links
- 238000009499 grossing Methods 0.000 claims description 72
- 238000001816 cooling Methods 0.000 claims description 31
- 238000001035 drying Methods 0.000 claims description 21
- 239000011248 coating agent Substances 0.000 claims description 15
- 238000000576 coating method Methods 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 14
- 238000004804 winding Methods 0.000 claims description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 238000011144 upstream manufacturing Methods 0.000 claims 1
- 239000011111 cardboard Substances 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 239000011087 paperboard Substances 0.000 description 4
- 238000005096 rolling process Methods 0.000 description 3
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 239000000049 pigment Substances 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 229920002472 Starch Polymers 0.000 description 1
- 239000003570 air Substances 0.000 description 1
- 239000012080 ambient air Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000003490 calendering Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000006735 deficit Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000010422 painting Methods 0.000 description 1
- 239000000123 paper Substances 0.000 description 1
- 235000019698 starch Nutrition 0.000 description 1
- 239000008107 starch Substances 0.000 description 1
Images
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21G—CALENDERS; ACCESSORIES FOR PAPER-MAKING MACHINES
- D21G9/00—Other accessories for paper-making machines
- D21G9/009—Apparatus for glaze-coating paper webs
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21G—CALENDERS; ACCESSORIES FOR PAPER-MAKING MACHINES
- D21G1/00—Calenders; Smoothing apparatus
- D21G1/0073—Accessories for calenders
- D21G1/0093—Web conditioning devices
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21G—CALENDERS; ACCESSORIES FOR PAPER-MAKING MACHINES
- D21G7/00—Damping devices
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
Definitions
- the invention relates to a method for treating a fibrous web, in particular a paper or cardboard web, in the end section of a machine for producing the same, which has a drying section for drying, a first smoothing device for pre-smoothing, a coating device for applying coating paint, and a further smoothing device and a winding device for winding up the finished fibrous web, wherein the fibrous web is guided between the drying section and the winding device through at least one cooling unit with evaporative cooling.
- a paper or cardboard machine with a headbox, former, press and dryer section is usually used.
- a calender and/or a coating device are usually arranged at the exit of the drying section or behind a drying group within the drying section.
- the web is smoothed and, if necessary, compacted in the calender.
- a pigment-containing coating color is applied to one or both surfaces of the web.
- the object of the invention is to ensure volume-saving smoothing and, if possible, improved surface quality when rolling up.
- the object was achieved in that the fibrous web is cooled in front of the first and between the first and the further smoothing device by means of at least one cooling unit.
- the fibrous web between the further smoothing device and the winding device should also be cooled by means of at least one cooling unit.
- the fibrous web is cooled and moistened by means of a cooling unit in such a way that the absolute moisture content changes by less than 1% and preferably remains approximately constant.
- the cooling of the fibrous web is the basis for volume-saving smoothing and the least possible impairment of the line when rolling up.
- Evaporative cooling proves to be efficient cooling.
- heating of the fibrous web during smoothing and painting also leads to a loss of moisture.
- the temperature of the fibrous web should also fluctuate as little as possible in this section of the machine. It is therefore preferable to cool at several points spaced apart from one another in the direction of web travel.
- the fibrous web should be cooled such that the temperature of the fibrous web in front of the rewinder is at most 50 ° C.
- the fibrous web should be cooled for the first time before the first smoothing device.
- Cooling is preferably carried out using air. Because of the associated evaporative cooling, the fibrous web in the cooling unit should be moistened using sprayed water.
- the fibrous web should preferably be heated and moistened on both sides using steam.
- the heating is limited to the surface area of the fibrous web, so that volume-saving smoothing can still be guaranteed due to the cool core of the fibrous web.
- cooling can be carried out using evaporative cooling.
- cooling and/or moistening of the fibrous web can be adapted to the needs and the nature of the web, i.e., for example, that the fibrous web can be acted upon on one or both sides and the moistening also takes place at several points spaced apart from one another in the web running direction.
- At least one side of the fibrous web should be heated in each smoothing device. This means that at least one of the smoothing rollers of the smoothing devices is heated.
- the smoothing is carried out in the following, further smoothing device with relatively low pressing pressures, which is why it is advantageous if the total residence time of the fibrous web in the smoothing gap or gaps of the further smoothing machine is significantly longer than in the smoothing gap or gaps in the first smoothing machine .
- the fibrous web should be smoothed in the further smoothing device using smoothing rollers, at least one of which has an elastic jacket cover.
- the first smoothing device only has smoothing rollers with a hard outer surface.
- FIG. 1 shows a system diagram of an end section of a machine for producing a paper or cardboard web.
- the sheet is formed in the former from at least 3, maximum 5 layers, with at least one layer being formed by a fourdrinier wire.
- the fibrous web 1 passes through at least two elongated press nips, the fibrous web 1 passing through the first press nip together with an endless, water-absorbing dewatering belt on both sides and the fibrous web 1 coming into direct contact with a smooth press roller in the last press nip .
- the first drying group is formed by only 2 to 4 drying cylinders and has only one drying wire, preferably running endlessly over the fibrous web 1, which guides the fibrous web 1 around the drying cylinders.
- a medium preferably starch
- a medium can be applied to the fibrous web 1 on one or both sides via a coating unit.
- the fibrous web 1 is exposed to ambient air on both sides by a first cooling unit 6.
- the temperature of the fibrous web 1 decreases from 70 to 100 ° C to values between 10 and 40 ° C.
- the humidification device 8 in the form of a steam blowing box applies steam to the fibrous web 1 on both sides, which leads to the heating of the steamed web surface but also to the formation of condensation on it.
- the re-moistening supports the subsequent smoothing, especially when the web side with the condensate layer comes into contact with a heated smoothing roller of the first smoothing device 3.
- the heating caused by the steam does not have a significant effect on the cool core of the fibrous web 1, so that the smoothing in the first smoothing device 3 takes place in a volume-conserving manner.
- the first smoothing device 3 is formed here by two smoothing rollers with a hard outer surface pressed against one another, which allows intensive smoothing and thickness profiling. In addition, at least one of the smoothing rollers is heated from the inside and/or outside.
- the fibrous web 1 enters a coating device 9 with two to five separate coating units, in which a pigment-containing line is applied to one or both sides of the fibrous web 1 in a manner known per se.
- the web temperature rises again to values of 60 to 90°C.
- the fibrous web 1 is cooled again to a temperature of less than 50 ° C in front of the winding device 5 in at least one further cooling unit 7, 10.
- the fibrous web 1 can be smoothed in a volume-saving manner due to the relatively low temperature via a further smoothing device 4 located between the coating device 9 and the winding device 5. Therefore, at least one of the further cooling units 7 should be present between the coating device 9 and the further smoothing device 4.
- the further smoothing device 4 is also formed by two smoothing rollers pressed against one another, one of which is heated.
- a smoothing roller has an elastic jacket cover.
- this smoothing gap is designed to be extended, so that the residence time of the fibrous web 1 in this smoothing gap is significantly longer than in the smoothing gap of the first smoothing device 3.
- the smoothing in the smoothing gap of the further smoothing device 4 can be carried out with lower pressing pressure, which protects the volume.
- the fibrous web 1 reaches the winding device 5 for winding, with a further cooling unit 10 being able to be arranged between the smoothing device 4 and the winding device 5.
- the fibrous web 1 between the drying section 2 and the rewinding device 5 is moistened and cooled via the respective cooling units 6,7,10 in such a way that the moisture content changes absolutely by less than 1% across each cooling unit 6,7,10 and preferably remains approximately the same.
- the moisture content of the fibrous web 1 in this end section of the machine is between 6 and 11%.
- the fibrous web 1 is cooled in such a way that the temperature of the fibrous web 1 in front of the reeling device 5 is at most 50 ° C.
Landscapes
- Paper (AREA)
- Treatment Of Fiber Materials (AREA)
Claims (13)
- Procédé pour le traitement d'une bande fibreuse (1), en particulier d'une bande de papier ou de carton, dans la section finale d'une machine pour sa fabrication, qui comprend, en suivant le sens de défilement de la bande (11), une section de séchage (2) pour le séchage, un premier dispositif de lissage (3) pour le pré-lissage, un dispositif de couchage (9) pour l'application de peinture de couchage, un autre dispositif de lissage (4) ainsi qu'un dispositif d'enroulement (5) pour l'enroulement de la bande fibreuse (1) terminée, la bande fibreuse (1) étant guidée entre la section de séchage (2) et le dispositif d'enroulement (5) par au moins une unité de refroidissement (6, 7, 10) avec refroidissement par évaporation et étant refroidie avant le premier (3) et entre le premier (3) et l'autre dispositif de lissage (4) au moyen respectivement d'au moins une unité de refroidissement (6, 7, 10), caractérisée en ce que la bande fibreuse (1) est réchauffée et humidifiée au moyen de vapeur après le premier refroidissement et avant le premier dispositif de lissage (3).
- procédé selon la revendication 1, caractérisé en ce que la bande fibreuse (1) est refroidie entre l'autre dispositif de lissage (4) et le dispositif d'enroulement (5) au moyen d'au moins une unité de refroidissement (6, 7, 10).
- procédé selon l'une des revendications précédentes, caractérisé en ce que la bande fibreuse (1) est refroidie et humidifiée au moyen de l'unité de refroidissement (6, 7, 10) de telle sorte que la teneur en humidité varie de moins de 1% en valeur absolue.
- procédé selon l'une des revendications précédentes, caractérisé en ce que la bande fibreuse (1) est refroidie et humidifiée au moyen de l'unité de refroidissement (6, 7, 10) de telle sorte que la teneur en humidité reste à peu près constante.
- Procédé selon l'une des revendications précédentes, caractérisé en ce que la bande de matière fibreuse (1) est refroidie de telle sorte que la température de la bande de matière fibreuse (1) avant le dispositif d'enroulement (5) est de 50°C au maximum.
- Procédé selon l'une des revendications précédentes, caractérisé en ce que la bande fibreuse (1) est refroidie une première fois avant le premier dispositif de lissage (3).
- Procédé selon l'une des revendications précédentes, caractérisé en ce que la bande fibreuse (1) est humidifiée dans l'unité de refroidissement (6, 7, 10) avec de l'eau pulvérisée.
- procédé selon l'une des revendications précédentes, caractérisé en ce que la bande fibreuse (1) est chauffée et humidifiée des deux côtés avec de la vapeur.
- Procédé selon l'une des revendications précédentes, caractérisé en ce que la teneur en humidité de la bande fibreuse (1) entre la section de séchage (2) et le dispositif d'enroulement (5) est comprise entre 6 et 11%.
- Procédé selon l'une des revendications précédentes, caractérisé en ce qu'au moins une face de la bande fibreuse (1) est chauffée dans chaque dispositif de lissage (3, 4).
- procédé selon l'une des revendications précédentes, caractérisé en ce que le temps de séjour total de la bande fibreuse (1) dans la ou les colonnes de lissage de l'autre dispositif de lissage (4) est sensiblement plus long que dans la ou les colonnes de lissage du premier dispositif de lissage (3).
- procédé selon l'une des revendications précédentes, caractérisé en ce que le lissage de la bande fibreuse (1) dans le premier dispositif de lissage (3) est effectué au moyen de cylindres de lissage à surface d'enveloppe dure.
- Procédé selon l'une des revendications précédentes, caractérisé en ce que le lissage de la bande fibreuse (1) dans l'autre dispositif de lissage (4) est effectué au moyen de cylindres de lissage, dont au moins un présente un revêtement d'enveloppe élastique.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE102017106050 | 2017-03-21 | ||
PCT/EP2018/052064 WO2018171959A1 (fr) | 2017-03-21 | 2018-01-29 | Traitement de bande |
Publications (2)
Publication Number | Publication Date |
---|---|
EP3601666A1 EP3601666A1 (fr) | 2020-02-05 |
EP3601666B1 true EP3601666B1 (fr) | 2024-01-17 |
Family
ID=61132422
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP18702468.2A Active EP3601666B1 (fr) | 2017-03-21 | 2018-01-29 | Traitement de bande |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP3601666B1 (fr) |
CN (1) | CN110446811B (fr) |
WO (1) | WO2018171959A1 (fr) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102021113813A1 (de) | 2021-05-28 | 2022-12-01 | Voith Patent Gmbh | Verfahren und Vorrichtung |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FI105935B (fi) * | 1996-12-03 | 2000-10-31 | Valmet Corp | Menetelmä paperin kuivaamiseksi sekä paperikoneen kuivapää |
FI971301A (fi) * | 1997-03-27 | 1998-09-28 | Valmet Corp | Menetelmä paperin käyristymän hallitsemiseksi paperikoneen kuivatusosalla ja paperi- tai kartonkikone |
DE10255907A1 (de) * | 2002-11-29 | 2004-06-24 | Voith Paper Patent Gmbh | Maschine zur Herstellung und/oder Behandlung einer Faserstoffbahn |
DE102006051537A1 (de) * | 2006-10-27 | 2008-04-30 | Voith Patent Gmbh | Vorrichtung zum Bearbeiten einer Bahn aus Papier oder Karton |
DE102010029617A1 (de) * | 2010-06-02 | 2011-12-08 | Voith Patent Gmbh | Verfahren zur Herstellung einer gestrichenen, mehrlagigen Faserstoffbahn |
EP2682520B1 (fr) * | 2012-07-03 | 2016-06-22 | Valmet Technologies, Inc. | Procédé de production d'une bande fibreuse et ligne de production d'une bande fibreuse |
EP2765237B1 (fr) * | 2013-02-06 | 2016-11-23 | Valmet Technologies, Inc. | Procédé de production d'une bande de fibres et ligne de fabrication d'une bande de fibres |
EP2876206B2 (fr) * | 2013-11-21 | 2023-03-01 | Valmet Technologies, Inc. | Procédé de produktion de bandes de fibres et ligne de fabrication de bandes de fibres |
-
2018
- 2018-01-29 WO PCT/EP2018/052064 patent/WO2018171959A1/fr unknown
- 2018-01-29 EP EP18702468.2A patent/EP3601666B1/fr active Active
- 2018-01-29 CN CN201880019679.5A patent/CN110446811B/zh active Active
Also Published As
Publication number | Publication date |
---|---|
WO2018171959A1 (fr) | 2018-09-27 |
CN110446811B (zh) | 2021-06-04 |
CN110446811A (zh) | 2019-11-12 |
EP3601666A1 (fr) | 2020-02-05 |
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