FI118481B - Procedure and arrangement for bank check in a connection point for a sheet forming machine sub-assemblies - Google Patents

Description

1 18481

METHOD AND APPLICATION IN CONSTRUCTION MANAGEMENT AT THE INTERFACE OF THE MACHINE MAKING COMPONENTS

The invention relates to a method of controlling a web at a junction of a subassembly of a web forming 5, wherein, depending on the need for control, the web is either: transfer link. The invention also relates to an arrangement in web control at the junction of a subassembly of a web forming machine.

U.S. Patent No. 5,281,308 discloses an arrangement according to the preamble. From the web passing over the forming tissue which is the presenting tissue, the thread is first cut. At the start of the threading, the threading tape is transferred to a press fabric constituting a tissue taken from the forming fabric by a vacuum formed by a vacuum pick-up roll. When the tympanic * "is successful, the tympanic strip is spread to a full-width web, which at the same time moves to the press fabric. During production ·· · * V 25, the full-width web moves from the forming fabric with the help of the pressurized fabric. own tools are required to cut the edge band.

• * · ϊ ,,. Ϊ Surgery can also easily fail, requiring the entire head to be restarted from the beginning.

: 30 • φ ·

Nowadays, the press section uses what is known as a closed: export and thus the press section lacks threading means.

* ·· *, ···, in which case the above method is not applicable. Thus, at present, the * * [·] web is transferred at full width from the forming fabric to the * · · '· · · 35 dock. In practice, when starting the transfer, the pick-up roller and • * *. ·· * are thus moved towards the forming fabric, whereby the web is intercepted according to the press fabric. However, in the course of the transfer, the pathway is vaguely detached from the forming tissue and folds many times. Also, the part of the web that has been lowered before the transfer from the forming wire to the pulper is often ejected. Thus, the track 5 enters the press nip on the press member in vague and even bulky pulps. Although the press nipple is usually unloaded or so-called open during the head stroke, the mass jigs cause point shocks to the press nip. Especially the long nip roll belt belt is sensitive to such impacts. In practice, a mass mite, even when exposed to an open puris-10 tinnitus, causes a puncture pressure stroke on the belt diaper. At this pressure stroke, the lubricating oil film between the load shoe and the belt sheath disappears, causing the belt sheath to be damaged or at least locally worn faster than the rest of the area. The same problem occurs with track cutting, whereby, during production, it is necessary to lift the pick-up roll off the forming wire and again drive the track down to the pulper. Often, the track cut has to be made unexpectedly, which can cause the press nip to be loaded despite the quick release. Thus, even small local pressure shocks cause the aforementioned problems. Also in web cutting, web tearing is vague and pulp enters web parts into the press nip.

It is an object of the present invention to provide a novel method of controlling the track at a junction of · · · · 25 web forming machine subassemblies which can be implemented in various track control situations without damage to the subassemblies. It is also an object of the invention to provide a novel arrangement for the control of the web at a junction of a web-forming machine subassembly ϊ,., Ϊ having a simple and durable arrangement, which can be located at various junctions. The characteristic features of the process of the present invention are disclosed in the appended claim 1. Corresponding ···. The features of the arrangement according to the invention are evident from the appended claim 6. According to the invention, in various transition stages, the track is cut in a controlled manner, thus avoiding the problems of the prior art. Cutting can be achieved • · 1 1 8481 3 simply and inexpensively without presets. In such cases, even in unexpected situations, the cut-off will work as planned. The arrangement according to the invention is simple and it is possible to place it in existing web forming machines without major modifications. It is also important to prevent additional track sections from getting into subassemblies. For example, damage to the long nip rollers forming the press nip is avoided. This especially increases the life of the belt diapers and avoids sudden belt breakages. 10 At the same time, headaches and track cuts can be made more worry-free if the reason requires it. At the same time, threading and trimming are accelerated and the junction remains even more tight. In this case, the need for cleaning is reduced, so that after the web break, the threading can be started earlier, which improves the efficiency of the forming machine.

The invention will now be described in detail with reference to the accompanying drawings, in which:

Fig. 1 shows one position of the arrangement of the invention at the junction of the web forming part and the press part, Fig. 2 shows another position of the arrangement of the invention: 25: the web forming part and the press part at the junction, «··

Figures 3a-d show various successive steps of a first embodiment of the method of the invention,

Fig. 3e shows an enlarged phase of Fig. 3d, ··· 30 Figures 4a-d show another of the method according to the invention: various successive stages, »· ·« ·· ·. * ··. Figure 4e shows an enlarged phase of Figure 4d, • ·

Fig. 5 shows a third position of the arrangement of the invention at the junction of the press section and dryer section 35.

4, 118481

Figures 1, 2 and 5 show three known press sections 10 as well as a portion of the preceding web forming members 11. Figure 5 further shows a horizontal overflow unit 13 following the press section 10 which starts the drying section 12. 5 All three press sections are subassemblies of three large web forming machines paper or board machine. Typically, the web forming member includes at least one forming fabric that supports and conveys the web to be manufactured. Correspondingly, the press section includes at least 10 one press fabric, one also supporting the web and carrying it forward. The web forming machine is deliberately divided into sub-assemblies which, in addition to the forming and pressing parts, include a drying section and a post-treatment section. Between successive subassemblies, the web may be lowered to pulper or other wreck handling. In this case, for example, in the event of an outage, the threading can start from the subassembly preceding the problem point. For example, if the web is broken by the press section, the web can be run down at the end of the forming section and resumed production by threading the press section.

20

So it is a matter of track management and its need varies. The web forming machine also includes means for establishing and removing the necessary transfer link between the forming fabric ***** and the press fabric for controlling the web at the junction according to the particular control need. In other words, M · • *,! depending on the need for control, the transfer link is formed and the web is · · ·, · · transferred from the forming fabric to the press fabric. On the other hand, it | t! the transfer link can be removed to lower the track to the pulp • · 1. The different management needs will be described in more detail later. In practice, in most cases, the means 19 are connected to a press fabric: * · .. to support a matched pick-up roll 20 which is adjustable: 2 relative to the forming fabric 16 (Figures 1 and 2). More generally, the orbit is detached from the predisposing subassembly * and transferred to the next adjoining subassembly *, · · · · t S · *, whereby a graft is formed between the two tissues. On the other hand, the pathway is cut off by removing the tissue transfer link. Thus, this operation can be carried out at the junctions of the various subassemblies, mainly depending on the structure of the forming machine.

5

Figures 3a-e illustrate the first need for control, which is here to start a threading process, also called packaging or picking. Herein, an embodiment is contemplated in which the web is moved from the forming section to the press section. In other words, the web 18 is detached from the forming fabric 16 and transferred to the press fabric 17, whereby a transfer connection is formed between the forming fabric 16 and the press fabric 17. In Fig. 3a, the web 18 is supported by the forming fabric 16 and is lowered to the pulper. When starting the threading, the pick-up * roll 20 is moved toward the track 18 on the forming fabric 16 as shown in Figure 3b. Due to the adhesion of the press fabric 16 and the vacuum effect created by the pick-up roll 20, the track 18 moves to follow the press fabric 17. At the same time, the track 18 is detached from the forming fabric 16. In the prior art, this step is very vague. Instead, according to the invention, the web is further cut off by guiding the web toward an obstacle which, in the direction of movement of the pressed fabric, is positioned at a distance from the presser web after the web release point. More generally, the M ·: V barrier is adapted to take up the tissue in the direction of movement of the web after the point of separation of the web from the uptake tissue. In Figures 1, 2 m and 5 the location of the barrier 22 according to the invention is shown in principle in a rectangle. When colliding with an obstacle, the course is cut in a controlled way and has a clear edge. In some applications, * ^, 5 ^ the truncated end of the web may go twice, however, the effect of !!! !!! 30 on the press nip and its load is, however: 1 *. nonexistent. In other words, controlled truncation avoids the »» ·, ···. the disadvantages of technology. In Figure 3d, the track 18 is already broken and advances on the underside of the press fabric 17. The truncated section • · · * · * · * drips down into the pulper without entering the press nipple. Figure 3e ·· * • * * ··· * 35 illustrates the situation in Figure 3d, enlarged. The solid 1 1 8481 6 thin line represents the position of the track 18 at the moment of impact. Otherwise, lane 18 is depicted by a dashed line.

Figures 4a-e show another need for control, which here is a 5 track cut. Again, an embodiment is contemplated in which the web is moved from the forming section to the press section. In other words, the web is cut off by removing the transfer link between the forming fabric and the press fabric. In Fig. 4a, during production, the web 18 runs from the forming fabric 16 to the press fabric 17. If necessary, such as a web break with a press member, the pick-up roll 20 is lifted off the forming fabric 16 as shown in Fig. 4b. In addition, the depressurization of the pick-up roller 20 is usually removed, whereby the track 18 proceeds to follow the forming tissue 16. After a short while, the possibly slightly folded track 18 collides with the barrier 22 according to the invention and breaks in a controlled manner. In this case, the end of the track becomes flat, thus avoiding the disadvantages of the prior art. In Figure 4d, both parts of the track follow their own tissues without harmful mass mites. Figure 4e shows a situation according to Figure 4d in which the track 18 collides with the barrier 22 and 20 in a controlled manner.

... According to the invention, regardless of the need for control, the track can be · · · · * cut off, thus avoiding, for example, pin punching of the press nip. At the same time, the contamination and thus the need for cleaning • · · * ·· · 25 are reduced. The barrier according to the invention is arranged in the direction of movement of the uptake tissue * · · * ··· * after the web release point, at a distance from the extruded tissue. Preferably, the barrier is disposed below the tissue receiving gravity. This provides the advantageous operation described above, in which the truncated parts of the web are • · · * ... · 30 gravitationally down into the pulper.

# · • · · • · · ··· ·. ***. At other points, the web forming machine can also utilize the method and arrangement of the invention. In Figure 5, the barrier according to the invention is placed at the juncture 21 of the press section 10 and the drying section 12 * * ***** 35. Here, the delivering fabric 14 is a lower blanket 23 arranged to pass through the press nip. on transfer wire 24. Again, picking is based on the under-pressure effect of the pick-up roll 20. At the same time, blowing 5 25 can also easily be fitted inside the transfer wire 24 which is more permeable to felt 23, which also functions on at least certain types of felt. More generally, blowing is fitted to the barrier, whereby the web is guided through the tissue by blowing better to cut the blade. In other words, the cut of the track is ensured by blowing. In Figure 5, the blow 25 is illustrated with an arrow pointing down. 10 When in contact with the blowing unit, the paper moths could block the blowing air outlet holes, thus impairing the smooth operation of the blowing unit.

The method and arrangement of the invention can also be applied, for example, in connection with a calender forming in a forming machine, especially in intermediate calendering. In this subset, the pathway is picked up from calender transfer tissue as donor tissue to calender transfer tissue. Conventional techniques can cause problems, particularly on a shoe or belt calender, in which the shoe belt strap may be damaged similarly to the press member. Similarly, the steel calender belt of the belt calender may be subjected to mass deformation requiring repair, which would be copied to the web in the calender nip. Also in the calender application ♦ ♦ ·, 25 can be used for blowing as a cutting aid.

: In practice, the barrier is placed surprisingly close to the tissues.

* ϊ During the transmission, the interval is adjusted so that the obstacle becomes * t «; ***: proximal tissue. For example, the spacing can be less than 50 mm.

M »30 This avoids long sections of track and almost obstructs the barrier. In its simplest form, the barrier is fixed, t · *** ·, making the structure very simple. However, production conditions may often vary, so the barrier may include support means 26 for adjusting the position and / or position of the barrier 22. In Figures 3e and 4e, different directions of motion are shown by arrows ·· *: *. * La. Significant adjustments include adjusting the barrier location for the tissue • · 8 118481 opening kidney and adjusting the tissue. In addition to or instead of the aforementioned adjustments, the support members may be arranged such that the barrier has an operating position and a resting position. In this case, the barrier is rotated to 5 operating positions when required, and when necessary, the barrier is rotated to a rest position (not shown). This improves occupational safety while avoiding tissue damage. At the same time, the barrier remains clean. On the other hand, the supporting members can be arranged in a compassionate manner. In this case, if the tissue could strike the barrier, the barrier would avoid the direction of travel of the tissue, thereby avoiding the immediate risk of tissue rupture. On the other hand, preferably, the sharp barrier may be turned perpendicular to the tissue. This avoids tissue damage but achieves sufficient web shear, especially if blasting on the opposite side of the tissue is used.

In practical tests, the barrier is arranged as a blade 22 'which is turned against the direction of movement of the web 18. In other words, the web is cut by cutting according to the invention. In the embodiments shown, the blocked blade remains in place and the moving web intersects when it hits the blade. This solution is simple 'ί' * 1 and reliable. In addition, the blade extends substantially over the entire width of the track i ·· ί.,. Ί. This will cut the entire course at once. The blade can: * ti consist of several blades or even single prongs.

Preferably, the blade is serrated, whereby the tooth tips ϊ S * i make small holes in the web, which easily breaks the web.

* · · • t • · • «t

Figures 3e and 4e show, in principle, the support member • · * of the barrier 22; met 26, which according to the invention is arranged as a protective wall 27 ··· · * '* ♦ 30 or at least part of a protective wall. In one application, · «·. *. the trunk blade holder body extends straight or curved downward • · · • · · * 11. * toward the pulper (not shown). In this case, the body acts as a guiding • · • · * ”protective wall to prevent unwanted mass mites • · *. ·. · From rising underneath the cutter blade and its holder, for example ··· · ... * 35 first press nip raised by lower felt with felt. In addition, a downwardly extending wall 28 provided with lubricating jets 29 may be connected to the holder body 9 118481. The lubricating jets guide the web to the pulverizer and keep the wall and even the guide wall clean.

The method and arrangement of the invention are advantageous in applications in which the web is conveyed by a press fabric to a press nip forming part of the press section, one of which is formed by a long nip roll. Obstacle cleavage prevents the formation of mass moles, which further eliminates problems in the 10 press nipples. In practice, the straight cut end of the track lifts the entire load shoe at a time, thereby avoiding pointy pressure shocks on the belt. This will increase the life of the belt diaper. On the other hand, there is less need for replacement belt diapers, which is utilized as a cost saving. Significantly, there is also a reduction in extra unscheduled belt diaper changes, which increases production time on a web forming machine. Similar advantages are obtained in the above-described blowing and belt calender applications.

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Claims (14)

10 1 18481 A method of controlling a web at a junction of web forming machine subassemblies, comprising, depending on the control need, either - detaching the web (18) from the delivering tissue (14) preceding the junction (21) and transferring the junction (21) to the following junction. or (15), the transmitting connection between the tissues (14, 15) being interrupted by removing the transfer connection between the tissues (14, 15), characterized in that, regardless of the need for control, (18) is further cut off by guiding the web (18) toward an obstacle (22) which, in the direction of travel of the receiving web (15), is spaced from the web (15) upstream of the web (18). Method according to Claim 1, characterized in that the web (18) is cut off by cutting. The method according to claim 1 or 2, characterized in that the cutting of the web (18) is ensured by blowing (25). • ♦ • · ♦ 25 «·· · Method according to one of Claims 1 to 3, characterized in that the take-up fabric (15) is arranged as a press fabric (17) for transferring the web (18) to a press nip forming part of the subassembly (10), of which: 30 long nip rolls. A method according to any one of claims 1 to 3, characterized in that the uptake tissue (15) is arranged as a drying fabric (24), whereby the track (18) is transferred to the blowing unit (13) of the sub-assembly (12) * · · · ... · 35 11 118481 6. An arrangement of track control at the junction of web forming machine subassemblies, comprising: - a subunit (10-12) preceding the junction (21) and a tissue (14) therethrough, - a subunit (10-12) following the junction (21) and ( Means for establishing a transfer connection between or removing tissues (14, 15) between the tissues (14, 15) for controlling the web 10 (18) at the junction (21) according to the respective control need, characterized in that the receiving tissue (15) in the movement direction, after the web (18) has been released, a barrier (22) is provided from the intervening tissue (15) for cutting the web (18) towards the barrier (22) regardless of the control need. Arrangement according to Claim 6, characterized in that the barrier (22) is arranged below the tissue (15) receiving the gravity. Arrangement according to claim 6 or 7, characterized in that the barrier (22) comprises support means (26) for adjusting the position and / or position of the barrier (22). • i: 25 I ·· | :. ·, Ϊ An arrangement according to claim 8, characterized in that • · *. : „.. ί that the support members (26) are arranged such that the barrier (22) has an operating position and a rest position. • ♦ ♦ • · · ·· *: *: 30 10. An arrangement according to claim 8 or 9. known · ♦ · '': in that the support members (26) are arranged in a positive manner. An arrangement according to any one of claims 8 to 10, characterized in that the support members (26) are arranged as a protective wall (27) or into the protective wall (27). 12 118481 Arrangement according to one of Claims 8 to 11, characterized in that the supporting elements (26) comprise a wall (28) arranged near the barrier (22), in which lubricating jets (29) are arranged. 5 Arrangement according to one of Claims 6 to 12, characterized in that the barrier (22) is arranged as a blade (22 ') which is turned against the direction of movement of the web (18). An arrangement according to claim 13, characterized in that the blade (22 ') extends substantially over the entire width of the web (18). 15