WO2012056095A1

WO2012056095A1 - Method and device for winding of fiber webs, especially of paper and board webs

Info

Publication number: WO2012056095A1
Application number: PCT/FI2011/050899
Authority: WO
Inventors: Jarmo Malmi
Original assignee: Metso Paper, Inc.
Priority date: 2010-10-29
Filing date: 2011-10-17
Publication date: 2012-05-03
Also published as: CN103189290A; AT514371A1; FI20106132A0; DE112011103574B4; FI20106132A; AT514371B1; FI122980B; CN103189290B; DE112011103574T5

Abstract

The invention relates to a method for winding fiber webs, particularly paper and board webs, in which method, partial web rolls (R1...Rn) are wound in a winding device, where partial webs (W1...Wn) are guided to rolls (R1...Rn) via a nip between a winding roll (12; 13) and the rolls (R1...Rn). In the method, substantially all partial webs (W1...Wn) are guided to the first winding roll (12) and substantially every second partial web (W1...W5) is guided to the second winding roll (13). The invention also relates to a device for winding fiber webs, particularly paper and board webs, which device comprises a winding roll (12; 13) for winding partial webs (W1... Wn) into partial web rolls (R1...Rn) via a nip between the winding roll (12; 13) and the roll being formed (R1...Rn). The device comprises the first winding roll (12), via which substantially all partial webs (W1...Wn) are arranged guidable, and the second winding roll (13), to which substantially every second partial web (W1...W5) is arranged guidable.

Description

Method and device for winding of fiber webs, especially of paper and board webs

The invention relates to a method according to the preamble of claim 1 for winding fiber webs, particularly paper and board webs, in which method, partial web rolls are wound in a winding device where partial webs are guided onto rolls via a nip between a winding roll and the rolls.

The invention also relates to a device according to the preamble of claim 8 for winding fiber webs, particularly paper and board webs, which device comprises a winding roll for winding partial webs into partial web rolls via a nip between the winding roll and the roll being formed.

It is known that a fiber web, e.g. paper, is manufactured in machines which together constitute a paper-manufacturing line which can be hundreds of metres long. Modern paper machines can produce over 450,000 tons of paper per year. The speed of the paper machine can exceed 2,000 m/min and the width of the paper web can be more than 11 metres.

In paper-manufacturing lines, the manufacture of paper takes place as a continuous process. A paper web completing in the paper machine is wound by a reel-up around a reeling shaft i.e. a reel spool into a parent roll the diameter of which can be more than 5 metres and the weight more than 160 tons. The purpose of reeling is to modify the paper web manufactured as planar to a more easily processable form. On the reel-up located in the main machine line, the continuous process of the paper machine breaks for the first time and shifts into periodic operation. The parent roll web produced in paper manufacture is full-width and even more than 100 km long so it must be slit into partial webs with suitable width and length for the customers of the paper mill and wound around cores into so-called customer rolls before delivering them from the paper mill. This slitting and winding up of the web takes place as known in an appropriate separate machine i.e. a slitter-winder.

On the slitter- winder, the parent roll is unwound, the wide web is slit on the slitting section into several narrower partial webs which are wound up on the winding section around winding cores, such as spools, into customer rolls. When the customer rolls are completed, the slitter-winder is stopped and the rolls i.e. the so- called set is removed from the machine. Then, the process is continued with the winding of a new set. These steps are repeated periodically until paper runs out of the parent roll, whereby a parent roll change is performed and the operation starts again as the unwinding of a new parent roll.

Slitter-winders employ winding devices of different types depending on, inter alia, on the type of the fiber web being wound. On slitter-winders of the multistation winder type, the web is guided from the unwinding via guide rolls to the slitting section where the web is slit into partial webs which are further guided to the winding roll/rolls on the winding stations into customer rolls to be wound up onto cores. Adjacent partial webs are wound up on different sides of the winding roll/rolls.

When winding up webs on winding stations, it is important that the web stays fast without sliding on the surface of the winding roll when entering the winding nip of the winding station, whereby the tension of the entering web remains in control. If/when sliding in practice occurs, it is important that possible surrounding distances of different lengths of the partial webs i.e. wrap angles of different sizes on the periphery of the winding roll are either eliminated or, if this is not possible, tension differences of the partial webs caused by the surrounding distances of different lengths have to be compensated by means of the winding technique using different winding parameters. If sliding on different winding stations is different, the partial web rolls are formed different of their hardness.

On some slitters of the multistation winder type known of prior art, the winding up of partial webs occurs on both sides of one winding roll, having the diameter of typically 1 ,200 mm or 1 ,500 mm. In these, the surrounding distances of partial webs are different on the winding stations positioned on different sides of the winding roll. As a solution for this, patent specification EP0478719 describes the use of a separate so-called tension interruption roll. By the tension interruption roll, the partial webs are locked onto the surface of the winding roll thus aiming to eliminate the effect of sliding. When the web tension provided by the unwinding device is this way interrupted before winding up, the winding up requires additional devices, e.g. centre drives of winding stations, which then again provide the web with tension required for winding up. Such a method is not cost-effective in terms of power consumption. A similar arrangement is described by patent specification US4508283. On some other multistation winder types known of prior art, the so-called three-roll winders, which are described e.g. by patent specification FI71708 and patent specification EP0711245, the winding up of partial webs occurs by means of two winding rolls, typically having the diameter of 850 mm or 1 ,000 mm, and a guide roll positioned between them. Partial webs are guided separate from each other before guiding to the winding rolls. In these, the roll surrounding distances of partial webs guided on different sides of the winder are optimised such that the distances on the periphery of the winding rolls and the periphery of the guide roll are substantially the same on the winding stations on both sides of the slitter- winder. To ensure uniform winding, the winding rolls and the guide roll are mechanically connected together and this group is driven by one electric motor. Such an arrangement prerequisites a tight mutual diameter tolerance in the manufacture of winding and guide rolls, thus making the manufacture of rolls require high precision. An object of the invention is to create a method and a device for winding fiber webs where problems caused by sliding are eliminated or at least minimised.

An object of the invention is to introduce an arrangement where different surrounding distances do not incur additional requirements for winding / the winder device. To achieve the above-mentioned objects and those which come out later, a method according to the invention is mainly characterised by what is presented in the characterising part of claim 1. A device according to the invention is mainly characterised by what is presented in the characterising part of claim 8.

According to the invention, substantially all partial webs pass via a first winding roll and substantially every second partial web is guided further to a second winding roll.

According to an advantageous embodiment of the invention, the winding up occurs by means of at least two winding rolls. The slitted partial webs are brought together, most suitably parallelly by means of the guide roll/rolls to the inner/rearmost winding roll, where every second partial web is wound up on its winding station, and the rest of the partial webs are guided to the outer/frontmost winding roll to be wound up on their own winding stations. The winding rolls advantageously have their own, separate drives and, according to an advantageous additional characteristic, the drive of the inner roll is the so-called master i.e. main drive and the drive of the outer roll is the so-called slave i.e. auxiliary drive.

Using the method and device according to the invention enables the winding of partial web rolls of different widths on the winding stations. When applying the invention, it is possible to use as the second winding roll of the multistation winder a roll having a shorter shell than the first winding roll.

According to an advantageous additional characteristic of the invention, the large wrap angle of the first winding roll, 60-270 degrees, most suitably 90-180 degrees, provides a tension interruption, whereby sliding causes no problems. Applying the method and device according to the invention provides considerable advantages. Compared to one-roll multistation winders known of prior art, it is possible to use winding rolls of smaller diameters, having the diameter of 800- 1 ,200 mm, most suitably 850-1 ,050 mm. In connection with the invention, there is no need for a tension interruption roll, because the partial webs guided onto the outer winding roll surround the inner winding roll at a wrap angle so large that this forms a natural tension interruption. Furthermore, the auxiliary drive of the outer roll according to an advantageous additional characteristic of the invention can tension or loosen the partial webs entering the winding stations of the roll when required. Additionally, compared to three-roll multistation winders known of prior art, the winding rolls are separately run according to an advantageous additional characteristic of the invention, whereby the production tolerances of the rolls are not so critical, thus facilitating the manufacture. Furthermore, the threading of the web is more simple and quick of its operations, because the web can be threaded via both winding rolls and there is no need to divide it or guide separately like on the three-roll multistation winder.

Next, the invention will be described in more detail with reference to the figure of the enclosed drawing, to the details of which the invention is intended by no means to be narrowly limited.

The figure schematically shows an implementation example of the invention. In the schematic example according to the figure, a parent roll 10 is on the unwinding section from where a full-width web W unwinding from the parent roll 10 is guided by guide rolls 11 to the slitting section. For clarity, slitting means, e.g. slitter blades, laser or water jet slitting means, have been omitted from the example of the figure but, in the slitting, the web W is slit in the longitudinal direction into partial webs W1... Wn, of which there are six (6) in the example of the figure. The figure shows the change of the full-width web W into partial webs W1...Wn at the point of the slitting section. From the slitting, the partial webs W1...Wn are further guided via the guide rolls towards winding rolls 12, 13 and to the first winding roll 12, on which a second partial web W2...W6 is guided for winding up into partial web rolls R2...R6 via the first winding roll 12 and every second partial web W1...W5 is guided for winding up into partial web rolls R1 ...R5 via the second winding roll. This arrangement according to the invention, where partial webs W1...W5 guided to the second, outer winding roll 13 surround the first, inner winding roll 12 at a wrap angle so large that this forms a natural tension interruption, requires no separate tension interruption roll.

In this description, partial webs are designated with reference W1...Wn and the example of the figure includes six partial webs W1...W6 which are wound into partial web rolls R1 ...Rn, in the example of the figure R1 ...R6. In the example of the figure, partial web rolls having an even reference number are wound on the first winding roll 12 and ones having an odd reference number are wound on the second winding roll 13 and equivalent partial web rolls are designated by an equivalent number index. However, this is not intended to limit the invention in any way. There can be less or more of the partial webs W1...Wn and naturally equivalently the number of partial web rolls being wound can be smaller or larger. According to the invention, the second partial web is wound on the first winding roll and equivalently every second on the second winding roll and the guiding order of partial webs for different winding rolls is not bound to the example of the figure. Furthermore, the widths of the partial webs can be the same and/or different for providing partial web rolls of the same and/or different width.

As evident from the figure, substantially all partial webs W1...Wn pass via the first winding roll 12 and every second partial web W1 , W3, W5 is guided to the second winding roll 13 and the winding up thus occurs via two winding rolls 12, 13. The slitted partial webs W1 ...Wn are brought together, most suitably parallelly by means of the guide roll/rolls 11 to the first/inner/rearmost winding roll 12, where every second partial web W2, W4, W6 is wound up on its winding station, and the rest of the partial webs W1 , W3, W5 are guided to the second/outer/frontmost winding roll 13 to be wound up on their own winding stations. The winding rolls 12, 13 advantageously have their own drives and the drive of the inner roll 12 is the so-called master i.e. main drive and the drive of the outer roll 13 is the so-called slave i.e. auxiliary drive. This auxiliary drive of the outer roll 13 can tension or loosen the partial webs W1...W5 entering the winding stations of the roll 13 when required.

The diameters of the winding rolls 12, 13 are 800-1 ,200 mm, most suitably 850- 1 ,050 mm. The wrap angle of the first winding roll 12 is advantageously large and the wrap angle is 60-270 degrees, most suitably 90-180 degrees.

The length of the first winding roll 12 and the second winding roll 13, advantageously their shell length, can be the same or different. Advantageously, as the second winding roll 13 is used a roll having a shorter shell than the first winding roll 12.

Between the first winding roll 12 and the second winding roll 13, there can be a tension measurement device of partial webs (not shown in the figure). This exterior tension measurement device of partial webs can be a measuring device not contacting the partial webs, e.g. a device based on ultrasonic sensors, or a contacting measuring device, e.g. a roll provided with tension measurement sensors.

The invention was described above referring to only one of its advantageous exemplifying embodiments to the details of which the invention is not intended to be narrowly limited but many modifications and variations are possible.

Claims

1. A method for winding fiber webs, particularly paper and board webs, in which method, partial web rolls (R1...Rn) are wound in a winding device, where partial webs (W1...Wn) are guided to rolls (R1 ...Rn) via a nip between a winding roll (12; 13) and the rolls (R1...Rn), in which method, substantially all partial webs (W1...Wn) are guided to the first winding roll (12) and substantially every second partial web (W1...W5) is guided to the second winding roll (13), characterised by, in the method, using the winding rolls (12; 13) by separate drives.

2. A method according to claim 1 , characterised by, in the method, slitting a full-width web (W) unwound on an unwinder (10) into partial webs (W1 ...Wn), bringing the slitted partial webs (W1 ...Wn) together, most suitably parallelly by means of a guide roll/rolls (11 ) to the first winding roll (12), where every second partial web (W2...W6) is wound up on its winding station, and the rest of the partial webs (W1...W5) are guided to the second winding roll (13) to be wound up on their own winding stations.

3. A method according to claim 1 , characterised by, in the method, operating the first winding roll (12) by a main drive and the second winding roll (13) by an auxiliary drive.

4. A method according to claim 3, characterised by, in the method, the auxiliary drive of the second winding roll (13) controlling the tension of the partial webs.

5. A method according to claim 1 , characterised by, in the method, winding at least two partial web rolls (R1 ... Rn) of different widths.

6. A method according to claim 1 , characterised by, in the method, winding at least two partial web rolls (R1 ... Rn) of the same width.

7. A method according to claim 1 , characterised by, in the method, the partial webs (W1 ...Wn) wrapping the first winding roll (12) at a wrap angle of 60-270 degrees, most suitably at a wrap angle of 90-180 degrees.

8. A device for winding fiber webs, particularly paper and board webs, which device comprises a winding roll (12; 13) for winding partial webs (W1... Wn) into partial web rolls (R1 ...Rn) via a nip between the winding roll (12; 13) and the roll being formed (R1 ...Rn), which device comprises the first winding roll (12), via which substantially all partial webs (W1...Wn) are arranged guidable, and the second winding roll (13), to which substantially every second partial web (W1...W5) is arranged guidable, characterised in that the winding rolls (12; 13) have their own drives.

9. A device according to claim 8, characterised in that the device further comprises an unwinder (10) for unwinding a full-width web (W) and slitting means for slitting the full-width web (W) into partial webs (W1...Wn), that the device further comprises a guide roll/rolls (11 ) for bringing the slitted partial webs (W1...Wn) together, most suitably parallelly to the first winding roll (12), where there are winding stations for winding partial web rolls (R2...R6), and that the second winding roll (13) of the device comprises winding stations for winding partial web rolls (R1...R5).

10. A device according to claim 8, characterised in that the drive of the first winding roll (12) is a main drive and the drive of the second winding roll (13) is an auxiliary drive.

1 1. A device according to claim 8, characterised in that the shell of the first winding roll (12) is longer than the shell of the second winding roll (13).

12. A device according to claim 8, characterised in that the diameter of the winding roll is 800-1 ,200 mm, most suitably 850-1 ,050 mm.