专利摘要:
Perforated passive deflection roller of a fiber web machine, which has a casing (21) and suction openings (22) which extend through the casing (21) and are arranged in several rows (23) surrounding the deflection roller (12), with both end regions (25) a groove (26) is arranged on the deflection roller (12) at the suction openings (22), the width (L) of which groove is smaller than the diameter (R) of the suction opening (22).
公开号:AT17352U1
申请号:TGM50035/2021U
申请日:2021-03-04
公开日:2022-01-15
发明作者:
申请人:Valmet Technologies Oy;
IPC主号:
专利说明:

description
PERFORATED PASSIVE DEFLECTION ROLLER OF A FIBER WEB MACHINE AND ARRANGEMENT ON A FIBER WEB MACHINE
The invention relates to a perforated passive deflection roller of a fiber web machine, which includes a jacket and suction openings extending through the jacket, which are arranged in several rows surrounding the deflection roller. The invention also relates to an arrangement on a fiber web machine.
The deflection roller is also called deflection suction roller or vacuum roller. The deflection roll is used in the single-wire draw of the drying section of a fiber web machine, in which a deflection roll is arranged between two drying cylinders. The drying fabric guided over the drying cylinders and deflection rollers presses the fibrous web to be produced against the drying cylinders. The fibrous web then lies on the very outside of the deflection roll, without any external support on the drying fabric.
In the pocket space delimited by the drying cylinders and the deflection roller together with the drying fabric, a runnability component is often also arranged, with which the pocket space is placed under negative pressure. Practically, the vacuum effect extends from the pocket space to the periphery of the perforated deflection roller, thereby preventing the fibrous web from detaching from the deflection roller and flapping of the edge regions of the fibrous web.
A certain combination of rolls and runnability components function properly with certain operating parameters. In order to maximize production, the speed of the fiber web machine should be kept as high as possible. At the deflection roller, the problems generally begin in the edge areas of the fiber web, which are poorer in terms of strength than the rest of the fiber web. Thus, the edge areas stretch and detach from the surface of the dryer fabric more easily than the rest of the fibrous web. The stretching degrades the quality of the end product and often even causes web breaks in the next stages of production. The speed has often been able to be increased by rebuilding the devices, but the problems of the edge areas of the fibrous web nevertheless arise in one phase.
The object of the invention is to provide a novel perforated passive guide roller for a fibrous web machine, in which the loosening and stretching of the edge parts of the fibrous web can be prevented without replacing the guide rollers. The characteristics of the deflection roll according to this invention are evident from claim 1 appended hereto. In addition, the object of the invention is to create a novel arrangement for a fiber web machine, with which the fluttering of the edge areas of the fiber web is prevented. The characteristics of the arrangement according to the invention are evident from claim 6 appended hereto. On the deflection roller according to the invention, the runnability components and suction openings of the deflection roller remain unchanged, but their vacuum effect is extended further than before. Thus, the negative pressure effect increases in the area of the edge parts of the fibrous web even with current runnability components and production parameters. In doing so, the speed limitation caused by the boundary problems is avoided. At the same time, the quality of the end product remains good. However, it is possible to further improve the increasingly stable situation with simple means. In addition, the existing deflection rollers can be used without large investments in devices when the arrangement according to the invention is formed. The composition of the arrangement can be defined on a case-by-case basis. The costs remain low and the problems can be solved locally.
The invention is described in detail below by referring to the accompanying drawings describing an application of the invention, in which
1a shows a drying group of the drying section of a fiber web machine equipped with deflection rollers as a basic drawing,
Fig. 1b shows the partial enlargement on a deflection roller,
Figure 2 shows part of the mantle of the deflection roll seen in the machine direction,
Figure 3a shows part of the mantle of the deflection roll according to the invention seen in the machine direction,
Figure 3b represents a partial cross-section of the mantle of the deflection roller according to the invention,
Figure 3c shows a partial enlargement of Figure 3a.
In Fig. 1a a drying group 10 is shown separately, of which several are arranged one behind the other in the drying section of a fiber web machine, more generally said at least one. The drying group 10 is composed of drying cylinders 11 and deflection rollers 12, over which the drying fabric 13 is guided as an endless loop. At present, a single-wire guide corresponding to the illustration is being used more and more, in which there is only one drying wire for a drying group. In practice, the fibrous web runs between the drying wire and the heated drying cylinder. The fiber web runs accordingly at the deflection roller on the drying fabric. In addition to the deflection roll, part of the arrangement used in the control of the fibrous web is a runnability component 14, which is placed in the pocket space 15 formed by successive drying cylinders 11 and deflection roll 12 (Fig. 1b).
In Fig. 15, a defined by the drying cylinder 11 and the drying fabric 13 gap 16 and correspondingly formed by the drying fabric 13 and the deflection roller 12 closing gap 17 are shown. The air entrained with the drying wire 13 and the fibrous web 18 causes problems particularly in the closing gap 17 where the air tries to escape through the drying wire 13. The peak-like overpressure that forms detaches the fiber web from the drying fabric. In particular, the edge areas of the fiber web detach easily and stretch at the same time. The entry of air into the closing gap 17 is shown here with a straight arrow. In practice, the air collected in the closing gap 17 causes overpressure which attempts to detach the fibrous web 18 from the surface of the drying fabric 13 at the deflection roll 12 . Also shown in Figure 16 are the blows 19 used to hold the tail threading strip to the dryer wire 13. During production, these blowouts are out of order.
The runnability component 14 is used particularly during production. The runnability component 14 has an air stub 20 at at least one end, and the runnability component 14 is open at the bottom. The negative pressure effect caused by the vacuum is directed onto the deflection roller 12, which includes a completely perforated jacket 21. In other words, suction openings 23 extend through the jacket 21 and are arranged in a plurality of rows 23 running around the deflection roller 12 (FIG. 2). The negative pressure effect extends via the suction openings into the deflection roller and from there everywhere in the area of the deflection roller. It is then a passive deflection roller that does not have a suction box or suction nozzle. The runnability component also has seals 24, with which an attempt is made to direct as much of the vacuum as possible into the deflection roller. From the deflection roll, the negative pressure effect in turn extends via the suction openings to the outer surface of the shell, with the fibrous web remaining on the path of the deflection roll on the drying wire.
In the arrangement, at least one deflection roller is a perforated passive deflection roller, in the two end regions 25 of which a groove 26 is arranged at the suction openings 22, the width L of which is smaller than the diameter R of the suction opening 22. Because of the grooves, the vacuum effect can be extended further and more evenly than before over the circumference of the jacket. In this way, air can be effectively removed in the closing gap, particularly in the edge areas of the fibrous web, and secondly, the edge areas on the drying fabric can be held firmly on the circumference of the deflection roller. The stretching of the
Edge areas and thus the fluttering and also later problems are avoided.
In the illustrated application, the opening effect of the opening gap 16 has been reduced. Here, the blowing 27 has been connected to the runnability component 14, which removes the air guided with the drying fabric. A seal can be used in place of or in addition to the blowout. A little air can also be fed into the gap arranged after the deflection roller, but this is now removed into the deflection roller without loosening the edge parts of the fiber web.
In Fig. 2, the perforated and passive deflection roller is shown for an end. As such, the drilling pattern is regular, although the suction openings also form diagonal rows 28 in addition to the rows 23 in the transverse direction, as shown in relation to the deflection roller. The structure is formed by having the suction ports of the parallel rows offset with respect to the subsequent suction ports. In other words, there is also a phase shift of the suction openings in the drilling pattern, which further evens out the distribution of the suction in the region of the deflection roller. There are suction openings and thus the negative pressure effect as evenly as possible over the entire circumference of the deflection roller. The drilling devices also partially produce a regular pattern when several suction openings arranged next to one another are drilled at once in the axial direction, after which the jacket of the deflection roller is rotated a little and the drills are displaced in the axial direction.
In Fig. 3a one end of the deflection roller corresponding to the invention is shown. Generally speaking, a groove 26 runs in the edge regions 25 of the deflection roller 12 at each suction opening 22. The rows of suction openings in the transverse direction are parallel, and there are also grooves next to one another. At the same time, in the end areas of the deflection roller in the area of the edge parts of the fibrous web, an increased negative pressure effect is formed, with which the edge parts of the fibrous web are effectively supported, with fluttering and other problems being avoided.
In the invention, the width W or W' of the grooved portion is 100 ~ 200 mm. Width W is in the application where scoring starts from the outermost row of holes. In the other application, grooves are already in front of the outermost row of holes. The drilling pattern primarily defines the number of grooves. In relation to the overall width of the fibrous web, it is a narrow but effectively vacuumed area. Thus, only a few grooves are needed, but the greatest benefit is gained at the edge portions. In FIG. 3a, grooves 26 are therefore already in front of the outermost row of holes in the application. Just one or two grooves on the smooth surface outside the perforated area from the end portion of the idler roll will help prevent an overpressure spike. Even if these outermost grooves were not even below the edge of the fibrous web, the overpressure peak becomes smaller as the cross flow under the dryer wire is reduced and the negative pressure of the pocket space in the grooves is effective. The arrangement of the drying wire can vary a little laterally, but the fibrous web is narrower than the drying wire, placing the edge parts of the fibrous web in the area with grooves. For example, the unperforated area is approx. 200 mm and the edge of the drying fabric is located in the unperforated area at a distance of approx. 70 mm from the edge of the deflection roll. The grooves are also beneficial in tip performance, although the tip performance stripe is significantly wider than the edge portion and also the grooved area. A part of the drying wire 13 and of the fibrous web 18 is also shown in FIG. 3a. Generally speaking, the scoring extends outside the edge of the fibrous web by at least two flutes. The negative pressure effect is guaranteed during the entire production.
With a groove the width of the diameter of the suction opening, a strong and uniform land between the grooves is ensured. In other words, opening of the suction port between two parallel grooves is avoided. At the same time, the formation of acute angles in the grooves is prevented. Generally speaking, on the way to the next suction opening of the same groove in the parallel grooves there are suction openings in different rows in the transverse direction. A ridge of the groove is then located at the parallel openings mentioned
Closing the suction port.
A narrow groove is also sufficient in practice. In the invention, the width L of the groove 26 is 0.2 - 0.8 times the diameter R of the suction opening. A narrow groove is easy and quick to process. At the same time, a web 29 supporting the drying fabric remains between the grooves. In the invention, a groove runs in the grooved area over each suction opening, advantageously in the middle of the suction opening. Thus, it is easy to process the grooves and the lands remain consistent. The amount of air flowing in the grooves is adjusted with the depth of the groove. In the invention, the depth S of the groove 26 is equal to or greater than the width L of the groove 26. Since the grooves are otherwise narrow, it is possible to machine deeper grooves in width to the surface of the cladding. In addition, grooves are only in the end areas of the idler roll, so the grooves have an insignificant effect on the load-bearing capacity of the idler roll. On the other hand, the vacuum effect is distributed effectively and covers the entire circumference of the deflection roller.
In testing, a suction port was used whose diameter was eight millimeters, the width of the groove was three millimeters and the depth of the groove was four millimeters. At this time, the air present in the groove could surely be removed via the suction openings of the groove when the flow area of the suction opening was several times the cross-sectional area of the groove. However, the width of the groove is smaller than the diameter of the suction opening. Known suction openings are generally 8-8.5 mm in diameter, but 6 mm are also possible. The operating speed of the fiber web machine defines in part the required width of the groove, the faster the operating speed the wider the groove. The depth of the groove acts in a corresponding manner.
Generally speaking, the groove is at least 3mm, but at most 6mm wide. The depth of the groove would be 4 - 5 mm.
In Fig. 3b a part of the jacket 21 is shown in cross section. In the jacket 21 there are suction openings 22 extending through the jacket 21, via which the grooves 26 have been processed. The negative pressure effect created by the suction openings in the deflection roller extends through the drying fabric to the fiber web and is distributed over a wide area via the grooves. The negative pressure removes at least the overpressure created by the closing gap and prevents the formation of an overpressure spike (Fig. 1b).
The deflection roller corresponding to the invention is advantageously formed by an existing perforated deflection roller. The width of the groove is first defined on the basis of the suction openings and their drilling pattern. In the invention, the width is smaller than the diameter of the suction port. The deflection roller can be removed from the fiber web machine and taken to processing. However, the number of grooves required is so small and they are always arranged in the end area of the deflection roller that the grooves can be processed by leaving the roller installed. After removing the dryer fabric, a tool holder is attached near the deflection roll. The tool can also be held in place with a simple tool holder and at the same time the arrangement of the tool can be adjusted both in the axial and in the radial direction when the deflection roller rotates. It is primarily turning, in which the tool is used to process the workpiece by rotating the piece. A cast iron coat is easy to work with. After processing, the grooves are checked and any sharp edges are ground down.
The suction openings are also lowered or rounded at the edges.
On a deflection roller, twenty grooves were processed in the end area, corresponding to that shown in Fig. 3a. After the initial preparations and attachment of the tool holder, the processing of the grooves took almost an hour. This means that several deflection rollers can be processed during a maintenance shutdown. In addition, it is not necessary to process all the deflection rollers. In demanding positions, such as the first deflection rolls of the dryer group and in particular the processing of deflection rolls at the beginning of the dryer section, this can already be sufficient. On new fiber web
machines and machine conversions, the deflection rollers are processed during roller maintenance or during production before installation on the fiber web machine.
Stretching and loosening of the edge parts of the fibrous web can even be detected visually or at least with a video camera. If a problem is identified, changing the production parameters can control the problem. Decreasing the speed and increasing the vacuum effect of the runnability component keeps the edge parts under control. The situation is also made easier by reducing the draw difference between the dryer groups. However, for production reasons, the speed should be kept as high as possible, but the draw difference should be low, with the runnability being able to be compensated for by increasing the draw difference. In addition, the runnability components often function at maximum performance. Sooner or later the problem will come up somewhere. Now, with the deflection roller according to the invention, a quick solution to the problem is achieved without limiting production or rebuilding the devices. By preventing the problem from arising at the outset, it is possible to adjust subsequent dryer sections and their runnability components to lower performance than before, while at the same time saving energy. According to the tests, the runnability of the guide roll was good and the fluttering of the edge parts of the fibrous web was avoided. Based on the test results, the suction effect with the grooving according to the invention is greater than before, precisely in the right places, ie in the edge areas of the fibrous web. After a certain limit, the edge parts of the fibrous web also achieve sufficient strength. This prevents stretching and thus avoids later problems. During production, the fibrous web runs through the dryer sections, even if slight detachment would take place in the edge areas. Passive deflection rollers are even used up to a speed of 1200 meters per minute. Even at this speed, the fiber web ran without fluttering of the edge parts, so the problem could be easily solved.
权利要求:
Claims (6)
[1]
1. Perforated passive deflection roller of a fiber web machine, which has a casing (21) and suction openings (22) extending through the casing (21), which are arranged in several rows (23) surrounding the deflection roller (12), characterized in that in A groove (26) is arranged on both end regions (25) of the deflection roller (12) at the suction openings (22), the width (L) of which groove is smaller than the diameter (R) of the suction opening (22).
[2]
2. Deflection roller according to Claim 1, characterized in that a groove (26) runs in the end regions (25) on the suction opening (22).
[3]
3. Deflection roller according to claim 1 or 2, characterized in that the width (W, W') of the area provided with grooves (26) is 100 - 200 mm.
[4]
4. Deflection roller according to one of Claims 1 - 3, characterized in that the width (L) of the groove (26) is 0.2 - 0.8 times the diameter (R) of the suction opening (22).
[5]
5. Deflection roller according to one of claims 1-4, characterized in that the depth (S) of the groove (26) is equal to or greater than the width (L) of the groove (26).
[6]
6. Arrangement on a fibrous web machine, which has at least one drying group (10), which is formed by drying cylinders (11) and deflection rollers (12), over which a drying fabric (13) is guided as an endless loop in single-wire guidance, and at least one runnability component (14 ), arranged in the pocket space (15) formed by successively arranged drying cylinders (11) and deflection roller (12), wherein in the arrangement at least one deflection roller is a perforated passive deflection roller, which has a jacket (21) and through the jacket (21 ) has extending suction openings (22) which are arranged in several rows (23) running around the deflection roller (12), characterized in that the deflection roller (12) is a deflection roller corresponding to one of claims 1 - 5.
3 sheets of drawings
类似技术:
公开号 | 公开日 | 专利标题
DE3403642C2|1988-03-17|
DE3828743B4|2004-08-05|Method and device in a multi-cylinder paper machine dryer
DE3328162C2|1986-02-20|Paper machine
AT392991B|1991-07-25|DRYING PART FOR A MACHINE FOR THE PRODUCTION OR PROCESSING OF FIBER STRIPS, ESPECIALLY PAPER STRIPS
DE3504820A1|1985-09-12|DEVICE IN THE DRYING SECTION OF A PAPER MACHINE
DE3914761A1|1990-11-15|GUIDE ROLLER FOR A POROUS BAND, FOR EXAMPLE FOR A DRY SCREEN OF A PAPER MACHINE
AT391498B|1990-10-10|AIR GUIDE BOX FOR THE DRYING PART OF A HIGH SPEED PAPER MACHINE
AT508470B1|2012-04-15|METHOD AND DEVICE FOR TRANSMITTING A FIBER TRAIN FROM ONE SUPPORT FABRIC TO ANOTHER
DE3910600C2|1993-10-07|One-sieve dryer group
WO2014026920A1|2014-02-20|Sealing strip
DE3101407A1|1982-07-22|MATERIAL DRAIN DEVICE FOR A PAPER MACHINE
DE4314475A1|1993-12-23|Paper web passage through drying section - has sealing bar structure at deflection roller for roller surface recesses to generate underpressure without roller suction
AT394870B|1992-07-10|DRYING DEVICE
DE4009287B4|2005-02-24|Method and apparatus for drying a wet paper web in a paper machine dryer section
EP0989233A2|2000-03-29|Drying section and convection dryer for such a drying section
AT17352U1|2022-01-15|PERFORATED PASSIVE DEFLECTION ROLLER OF A FIBER WEB MACHINE AND ARRANGEMENT ON A FIBER WEB MACHINE
DE10024296B4|2008-11-20|Machine for producing a material web
DE4311351A1|1993-09-02|
DE4328555A1|1994-03-31|Paper-making machine twin-blanket drying section - has structured gap between suction deflection rollers in upper row of cylinders and blanket path at lower row to reduce web path
DE3220076A1|1983-12-01|AIR BLOWER BOX FOR THE DRYING PART OF A PAPER MACHINE
DE10058543A1|2002-01-24|Method and device for the continuous treatment of synthetic threads in a heat exchange chamber
EP1731665B1|2010-09-08|Impingement drying arrangement
DE4428745A1|1996-02-15|Paper=making machine drying section
DE3220074A1|1983-12-01|Drying section of a paper machine
DE4404726C2|1996-04-25|Pocket ventilation in a two-wire cylinder dryer
同族专利:
公开号 | 公开日
FI12670U1|2020-06-15|
DE202021101087U1|2021-03-12|
CN215625636U|2022-01-25|
引用文献:
公开号 | 申请日 | 公开日 | 申请人 | 专利标题
US4932138A|1988-03-09|1990-06-12|Valmet Paper Machinery Inc.|Method and device for threading a web around drying cylinders|
US6192597B1|1997-04-17|2001-02-27|Voith Sulzer Papiermaschinen Gmbh|Device for treating a fibrous pulp web as well as a sealing device for a device of this kind|
DE102007058728A1|2006-12-12|2008-06-19|Metso Paper, Inc.|Paper/cardboard web travel has an upper belt loop over it, on a carrier belt, with an overpressure unit before the deflection roller to detach the web from the upper belt and lie securely on the carrier belt|
法律状态:
优先权:
申请号 | 申请日 | 专利标题
FIU20204045U|FI12670U1|2020-03-12|2020-03-12|Perforated passive reverse roll in a fibrous web machine, and arrangement in a fibrous web machine|
[返回顶部]