FI123973B - Arrangement and method for threading a fiber web machine - Google Patents

Description

COMPOSITION AND METHOD FOR FIXING BY FIBER MACHINERY

The invention relates to an arrangement for threading with a fiber web machine comprising one or more rope nips formed by a thread rope for inserting a thread strap between the thread ropes and a threading means for inserting a thread strap into the rope nail, followed by a thread. The invention also relates to a method for threading 10 with a fiber web machine.

Still, at least some of the web threading utilizes fibrous web machines for threading ropes. Such parts include, for example, unsupported clearances. In successful threading, the 15 threading straps are first fed into a rope nipple where the threading ropes are closed and the threading strap is trapped between the threading ropes. The threading ropes travel at the speed of the fiber web machine and pass the thread web through the fiber web machine to the next holding point, such as a roll nipple. The threading strap 20 is fed between the threading ropes by any suitable threading device. An arrangement for threading is disclosed, for example, in European Patent No. 1431454. The threading ropes are typically in fibrous web machines adjacent to the web at some distance from the edge of the web. Hereby, the head-cut ribbon cut from the edge of the web must be pushed to the side of the rope nipple by means of a thread-cutting cutter co1 and possibly subsequent threading devices.

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^ European Patent Application Nos. 1580319 and 1783272 also disclose x 30 arrangements for threading.

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ld However, there are problems with the cable entries. With the threading device, an angle is formed between the threading device and the export direction of the threading ropes when inserting the threading strap into the rope nip. The stem-35 also has a cardboard filament strap which is stiff and starts to follow the filament rope at the same angle at which it is introduced. In practice, the angle determines how far the head-tin strap is between the head-ropes. The angle is usually so large that the length of the threading strap between the threading ropes is at most one meter, often even much less. This length of 5 is often inadequate, especially in long cable runs, to achieve a reliable threading, even if there are three threads. In practice, the threading strap may even slip between the threading ropes during threading, whereby it may drip off between the threading ropes thereby failing the threading. Another problem is the ribs forming on the headband, which can lead to a breakage of the headband in the middle of the head extension.

The object of the invention is to provide a novel arrangement for the export of the head-15 of a fiber web machine, which is simple in design and which avoids the problems caused by the lateral displacement of the headband. It is a further object of the invention to provide a novel method of threading a fiber web machine that can secure and even adjust the threading. Characteristic features of the arrangement according to the invention are that in the arrangement the threading ropes are arranged such that the direction of the tensioning ropes before the rope nip substantially corresponds to the direction of the tensioning strap defined by the threading means. Correspondingly, the feature of the method according to the invention is that the threading ropes are arranged so that

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^ before the rope nip, the direction of threading of the threading ropes substantially corresponds to the thread of the threading thread defined by the threading means. incoming direction. The arrangement is reliable and easily the smallest

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^ with modifications to fit different positions to ensure the threading success x x 30. The method can be widely applied to various cd fiber web machines without the need for major modifications. In addition, the 't S method offers versatile adjustment of the head opening. The remainder of the club with probability.

o As a result, the successful hair removal is much larger-

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The invention will now be described in detail with reference to the accompanying drawings, which illustrate some embodiments of the invention, in which a plan view of the prior art is shown in principle,

Figure Ib shows a partial magnification of the arrangement of image la a moment later,

Figure 2a is a side view of an arrangement according to the invention,

Figure 2b is a top view of the arrangement of Figure 2a,

Fig. 2c is a cross-sectional view of a threading strap treated with the method of the invention,

Fig. 3a is a side view of another embodiment of an arrangement according to the invention,

Figure 3b is a top view of the arrangement of Figure 3a,

Fig. 3c is a side view of an arrangement according to the invention,

Figure 3d is a plan view of the arrangement of Figure 3c.

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Figure 1a shows in principle an arrangement known per se for threading a fiber web machine. Fiber web machines are, for example, paper and board machines, where production is started with the help of a threading tape.

In practice, the threading strap is passed through a fiber web machine and then applied to the web. Fig. 1a shows only one position of a fiber web machine where the arrangement according to the invention? is realized. Similar positions may be present in the fiber web machine

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00 several. After forming the thread, the rest of the web x £ 30 is lowered.

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The fiber web machine includes one or more threading ropes (O) for feeding the threading strap (13) between the threading ropes (10) and (11). The threading ropes are endless and supported by loops on a plurality of rope pulleys 14, illustrating the rope nipples 12 formed in Figs.

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4 only part. Tail ropes form rope shafts that can be several tens of meters long and tether ropes can form very diverse routes. Typically, the thread ropes are offset from the actual web path, which allows the web to pass despite the thread ropes. Paper machines use two and, on board machines, typically three threading ropes to form one rope passage. The fiber web machine also includes a threading means 15 for feeding the tuft-strap 13 to the rope nipple 12. In Fig. 1a, the tuft-strapping means 15 consist of a non-pressurized belt conveyor, although other suitable devices may be used. It is also common to use various blowing means, such as blowing dampers, which are located in connection with the threading means for cutting the thread.

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Figure Ib illustrates the situation shortly after the end of the threading strap 13 has hit the rope nipple or, more specifically, the rope wedge formed by the preceding threading rope. The oblique upstream direction of the threading strap determines the length of the threading strap between the threading ropes 20. The length depends mainly on the width of the strap and the geometry of the position without any adjustment.

According to the invention, in the arrangement the threading ropes 10 and 11 are arranged so that before the rope nip 12 the

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The direction of direction of the lines 11 and 11 corresponds substantially to the direction of direction of the direction of the thread 13 which is defined by the threading means 15. In Figure 2b, the main? the direction of the tin strip 13 in the downward direction is indicated by an arrow. In this case, the headband coil goes without interruption to the rope nipple and continues to run between the x £ 30 rope ropes. Thus, slipping of the threading rib co is avoided. In addition, there is a sufficient length of S between the thread ropes for long thread ropes.

Oh with the threading equipment that brings the threading cord to the thread.

o The direction of entry of the main ropes is practically the same as that of the ropes

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35 5 Threading ropes can be run on a very complicated route to a rope wheel or other guide. However, after the rope nip, the direction of exportation of the tapping ropes substantially corresponds to the longitudinal direction of the fiber web machine. The export direction 5 of the threading ropes 10 and 11 is shown by the arrow in Figure 1a. The cable entry is not linear, but has oblique, curved and even vertical sections as shown in Figure 2a. Thus, the export direction refers to the main direction, ie from the beginning of the fiber web towards the end. This export direction is thus generally substantially parallel to the fiber web machine 10.

In Figure 2a, the first filament rope 10 comes from the top inclined with the second filament rope 11 coming down. The tensioning ropes 10 and 11 meet with the rope pulley 14, thereby forming a rope nip 15 12. Forward of the rope nip, the tensioning ropes 10 and 11 pass through one another to a holding point, such as a roll nip (not shown). Figure 2a illustrates a situation in which the threading strap 13 extends between the threading ropes 10 and 11. Theoretically, the threading strap goes continuously to the threading ropes 20 without ever leaving it. Figure 2b shows only the upper rope pulley 14. In addition, in reality, the thread strap lives as it progresses.

Thus, problems of the prior art can be solved by matching the upstream direction of the threading ropes and the upstream direction of the threading rope 25. In addition, it has been found that a small difference in angles of upstream direction can be influenced by the N-? between the length of the strap. According to the invention before

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The rope nip has an angle difference of 0 ° to 10 ° between the direction of the threading ropes and the direction of the £ 30 of the threading rope. Within this angular range ό, the length of the threading strap S which is fed between the threading ropes can be significantly influenced. The greater- σ> between the ropes.

35 o pi the angular difference, the shorter the length of the tongue left in the headband c \ j 6

In the embodiment shown, the threading ropes are supported at the beginning by a rope sheave. Later, the rope passage may pass through, for example, paper guide rollers. Here, at the rope nip 12, the threading ropes 10 and 11 are supported by a rope pulley 14 arranged at an angle to the longitudinal axis of the fiber web machine. In other words, the rope pulley 14 is simply pivoted, which is particularly evident from Figure 2b. If necessary, other ropes will also be modified to reflect the new geometry. Preferably, the direction and / or position of the rope pulley is adapted to be adjustable. Here, for example, the angle difference between the direction of the tensioning ropes and the direction of the tensioning strap can be adjusted simply by turning the rope pulley. Even with a slight change in the angle difference, the length of the tension strap between the tensioning ropes can be adjusted.

15 Adjusting the direction of tensioning of the ropes may require additional arrangements unless the geometry of the ropes allows it. In the embodiment of Fig. 2a, the arrangement includes the following rope pulley 16 which is arranged parallel to the longitudinal axis of the fiber web machine and arranged in a vertical line with respect to the rope pulley 14. Here, the following rope pulley 16 is below the rope pulley 14 forming the rope nip 14 with the rope outlet vertical.

Regardless of the structure of the arrangement, according to the invention, the threading eo · - ropes are arranged such that, before the rope nipple,

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The direction of entry substantially corresponds to the determination of the threading means between the threading ropes. When sufficient length is reached, the angle difference is increased, whereby the threading strap gradually begins to come out between the threading ropes. Another means is to remove the threading strap from the rope nip 12 by turning and / or moving the threading means 15 5. The turns of the threading means 15 are shown in principle with a double-headed arrow in Figure 1a. A third way is illustrated in Figure 2b, wherein the arrangement includes means 17 for removing the threading strap 13 from the rope nip 12. Here, the rope nip has an air blow to guide the tensioning strap 10 of the ropes without going into the rope nip.

Figures 3a and 3b show another embodiment of the arrangement according to the invention. Here, a threading device 15, such as a cutting device, puts the threading belt 15 into a rope nip 12 on a rope line with a rope wheel 14. The next rope wheel 16 is also located on a rope line. If the tapping rope 10 is vertical, then the rope pulley 14 would only be angled with respect to the centerline of the fiber web machine so that the axis 18 of the rope pulley 14 is horizontal. In Fig. 3a, the vertical tethering rope is shown with a dashed line. If the tensioning rope 10 is at another angle, such as that shown in Figure 3a, the rope pulley 14 is inclined such that the axis 18 of the rope pulley 14 is perpendicular to the plane defined by the rope line to and from the rope pulley 14. It is essential that, viewed from above, the direction of the co> rope line before the rope nip is substantially the same

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, the direction of threading of the thread defined by the threading means.

? For adjusting the length of the threading strap with the threading ropes

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deliberately deflecting the direction of the rope line, i.e. the direction of the rope wheel 14 x 30, with respect to the threading means 15, is 0 to 10 °.

co LO Figures 3c and 3d show a third embodiment of an arrangement according to the invention, for example, a cutting device for inserting a threading strap into a rope nip 12 35 with a rope pulley 14. The next rope pulley 16 is also located on the rope line. In this case, the rope pulley 14 is now tilted o application. Here, a threading means 15 parallel to the machine line, such as

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8 such that its axis 18 is perpendicular to the rope line entering and exiting the rope pulley 14. Correspondingly, the following rope pulley 16 is inclined such that its axis 18 'is perpendicular to the rope line 5 entering and exiting that rope pulley. These inclines, depending on the layout of the cable entry, result in the axles of the cable wheels not being generally horizontal or transverse to the vertical. Transverse vertical plane means any vertical plane transverse to the machine.

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The third embodiment described above can be further modified by fitting the rope nipple directly directly to the rope pulley adapted to the threading means parallel to the machine line. Thereafter, the rope wheels 15 of the third embodiment would be inclined according to the rope outlet layout.

In a further embodiment of the method according to the invention, the headband is treated prior to being introduced into the rope nip so that the thickness profile of the headband at least in one edge region 20 is smaller than in the middle region of the headband. Figure 2c shows a cross-sectional view of the treated thread 13. The treatment improves the durability of the headband so that it can withstand even the longest high speed cable runs. Typically, at the edge of the tensioning strap that touches the tensioning ropes, since the said edge carries the forces exerted on the tensioning strap, at least the rope side of the tensioning strap is treated so that the middle region r-- S5 of the tensioning strap is carried. Because the middle ground

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00 tearing is significantly harder at the edges, resistant to head-

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The £ 30 tin ribbon now improves on the forces applied to it and improves the reliability of the head piercing. In edge treatment, the edge of the headband S is extended longer than the center of the headband.

In other words, the length profile of the threading strap is changed from uniform to uneven. The treatment may be performed, for example, by sharpening the edge of the tongue of the fish-35 or by moistening the edge. The center of the strip thus treated receives the forces exerted on the strip while the edge remains loose. Of course, changing the length profile can be done in ways other than calendering.

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Claims (9)

An arrangement for threading with a fiber web machine comprising one or more rope nipples (12) formed by the threading ropes (10, 11) on the side of the web path for feeding the threading strap (13) between the threading ropes (10, 11) and the threading means (15). ) for feeding the tensioning strap (13) into the rope nip (12), after which the direction of export of the tensioning ropes (10, 11) substantially corresponds to the length 10 of the fiber web machine, characterized in that the tensioning ropes (10, 11) arranged at an angle to the longitudinal axis of the fiber web machine, whereby the direction of inlet of the tensioning ropes (10, 11) before the rope nip (12) substantially corresponds to the direction of tensioning of the tensioning strap (13). Arrangement according to Claim 1, characterized in that, before the rope nip (12), the angle difference between the direction of entry of the tensioning ropes (10, 11) and the direction of tensioning of the tensioning strap (13) is 0 ° to 20 °. Arrangement according to Claim 1 or 2, characterized in that the arrangement comprises an additional rope pulley (16) arranged parallel to the longitudinal axis of the fiber web machine and arranged in a vertical line with respect to the rope pulley (14), co δ c \ j Arrangement according to one of Claims 1 to 3, characterized in that the direction and / or position of the rope pulley (14) is CD_ adapted to be adjusted. £ 30 φ Arrangement according to one of Claims 1 to 4, characterized in that the arrangement comprises means (17) for removing the strap-to-tin strap (13) from the rope nip (12). CM A method of threading a fiber web machine comprising one or more rope nipples (12) formed from the end thread ropes (10, 11) on the side of the web path such that the direction of export of the thread ropes (10, 11) substantially corresponds to the longitudinal direction of the fiber web machine in turn, the threading means (15) are fed in turn by threading straps (13), characterized in that the tensioning ropes (10, 11) are supported at the rope nip (12) by a rope pulley (14) arranged at an angle to the longitudinal axis (12) of the 10, 11) substantially corresponds to the direction of direction of the threading strip (13) as defined by the threading lines (15). Method according to Claim 6, characterized in that the threading strap (13) is removed from the rope nip (12) by turning and / or moving the threading means (15). 15 A method according to claim 6 or 7, characterized in that the method uses an arrangement according to any one of claims 2 to 5. Method according to one of Claims 6 to 8, characterized in that, before being introduced into the rope nipple (12), the threading strap (13) is treated such that the thickness profile of the threading strap (13) is at least one edge region smaller than the middle region. co δ CM N- o CD CM X X Q. CD LO O O O CM