FI122416B - Scraping equipment for a fiber web machine and a method for adjusting the scraping equipment of a fiber web machine - Google Patents

Description

SCREENING EQUIPMENT FOR THE FIBER MACHINE AND METHOD FOR ADJUSTING THE SCREENING EQUIPMENT OF THE ΚϋΙΤϋ-PAPER MACHINE

The present invention relates to a scraping apparatus for a fiber web machine 5, which scraping apparatus includes a scraping blade, a blade holder to which a scraping blade is fitted, and a front edge forming plate provided in the blade holder for transferring load to a scraping blade.

The invention also relates to a method for adjusting the scraping apparatus of a fiber web machine.

For fiber web machines, the scraping device serves to remove impurities adhering to the moving surface by scraping the surface. To obtain a satisfactory cleaning result, the scraper on the scraper should touch the moving surface. Usually, the moving surface is a roll or cylinder. For example, the surface shape of the roller, errors in the installation of the scraper apparatus, or malfunctions of the lubricating jets 20 result in uneven wear of the scraper blade. This shortens the life of the scraper blade and results in an uneven scraping result.

The movable surface to be cleaned by the scraper consumes 25 scrapers of the scraper and produces an uneven width profile corresponding to the width of the movable surface,

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Y A scraping apparatus according to FI 119823 0 30 is known in the art, wherein the scraping blade of the scraping apparatus is loaded by means of a loading member. With such hardware

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it is almost impossible to influence the width profile of the scraper blade after installation since the scraper hardware is often ...

^ is located in a narrow space in the middle of rotating parts. Here

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Adjusting the 35 scraper equipment would require stopping or even partially disassembling the fiber web machine. On the other hand, the adjustment possibilities of the scraper apparatus are almost non-existent, with little adjustment potential. Thus, the doctor blade of the doctor blade is subjected to varying surface pressure, which results in poor profiling, resulting in rapid wear of the doctor blade and unnecessary wear of the roll surface. In other words, the scraper blade is affected by an uneven surface pressure, resulting in an uneven scraper blade wear and a further uneven width profile.

The object of the invention is to provide a new type of scraping apparatus for a fiber web machine and a method for adjusting the scraping apparatus of a fiber web machine 10, by which the wear of the scraping apparatus scraper is more uniform and the blade pressure is even. Characteristic features of the scraping apparatus of the present invention are set forth in claim 1 and features of the method of the invention are set forth in claim 6.

This object can be achieved by means of a scraping apparatus which includes a scraper blade, a blade holder and a support edge disposed in the blade holder, which is profiled to achieve a uniform surface pressure. The doctor blade is fitted in the blade holder. A support edge is provided in the blade holder to transfer the load to the doctor blade.

The scraping apparatus of the fiber web machine according to the invention may serve to remove impurities adhering to the moving surface by scraping the surface. The function may also be to remove the fibrous web from the t-movable surface (creping scraper) or to apply a coat, or similar layer, to the chamfer (coating blade). For sufficient cleaning, V creping or coating results,

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° The scraper blade of the machine must contact the moving surface with a surface pressure suitable for the purpose x £ 30.

Preferably, the width profile of the support edge is in accordance with the calculated and / or δ measured width profile of the doctor blade. The width profile profile of the support edge is profiled horizontally inverted with respect to the width profile 35 of the doctor blade. The profiled support edge provides even wear on the 3 scraper blades. At the same time, the blade pressure is constant.

According to one embodiment, the support edge is a front plate 5 which is removably attached. The blade holder and support edge may be made of fiber-reinforced plastic composite. The supporting edge may be profiled at the chamfer in the scraper assembly.

In the method of the invention for adjusting the scraping apparatus of a fiber web machine, a width profile of a scraping blade fitted to the blade holder is determined, which is the basis for adjusting the scraping apparatus. The adjustment is made by profiling the support edge provided in the blade holder, which transmits the load from the blade holder to the scraper blade.

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According to one embodiment of the method, the support edge is profiled by water cutting, which is a preferred machining method. In the method, the supporting edge of the doctoring apparatus according to the invention can be used as the supporting edge. The width-20 profile of the scraper blade fitted to the blade holder can be determined by removing the worn scraper blade from the scraper apparatus and measuring the wear with the measuring apparatus.

More specifically, the doctoring apparatus according to the invention is characterized in that the faceplate bevel is profiled to achieve a uniform surface pressure. The method according to the invention is characterized in that the adjustment is made by profiling a support edge arranged in the blade holder, which transmits the load from the blade holder to the doctor blade.

I 30 (M A significant 00 is obtained with the scraping apparatus according to the invention

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m advantage of even wear on the doctor blade scraper, which in part is due to more even blade pressure. Kaavinlait-

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the repetition can be designed without taking into account the roller surface diameter differences or the distortion of the mounting of the holder, for example 35 rollers. Scraper blades last longer and 4 work better. This results in longer blade replacement intervals and savings in scraper blade costs. In addition, the scraping result of the scraping apparatus according to the invention is superior to prior art apparatus. In other words, the scraper hardware corrects the 5 errors with the profiled support edge, whatever the cause. In this way, the operation of the scraper equipment can be optimized without searching for the parameters of the scraper equipment, which saves time and costs.

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

Fig. 1 is a sectional view of an assembly of the inventive inventive apparatus;

Figure 2 is an axonometric view of an end-supported scraper assembly as a whole, Figure 3 is a graph showing the calculated and / or measured width pro-20 of the scraper apparatus according to the invention,

Fig. 4 is a graph showing the width profile of the support edge of a scraping device according to the invention.

Fig. 1 shows an embodiment of the scraping apparatus 25 according to the invention, in a side elevational view, with the scraping apparatus 16 of the scraping apparatus in contact with the roll surface 26.

The purpose of the scraping apparatus 10 is to scrape the surface V of the roll 26 so that impurities adhering to the roll 26 are removed from the scraper.

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° on the ridge. The scraping apparatus preferably comprises a body 12,

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In addition, the scraper assembly has a support edge 18 connected to the blade holder 14 00 S, which transmits the load to the doctor blade o 16. This support edge 18 is a sideways movable front panel 18 '. The front panel can also be referred to as a presser 35.

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In the embodiment of Figure 1, pressure is exerted on the scraper blade 16 by a loading member 24 between the body portion 12 of the scraper device 10 and the blade holder 14, which tends to pivot the blade holder 14 around the support portion 46 5. The general structure of the scraper apparatus may be similar to that of FI 119823.

The body 12, the blade holder 14 and the supporting edge 18 can be made of, for example, fiber-reinforced plastic composite. When fiber-reinforced composites are used as materials for making the scraper apparatus, the deflection of the scraper apparatus itself also necessitates a profiling of the support edge. The body portion 12 is attached, for example, to the scraper bar 36 shown in Figure 2. 15 The blade holder 14 forms a functional scraper bar supported only at its ends 27. The individual deflection of the blade holder 14 can then be taken into account when profiling the support edge 18. The product name of the prior art scraper apparatus of the applicant shown in Figure 2 is FiberDocLite, Finnish Patent FI 120461.

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Further, in Fig. 1, the loading member 24 is secured to the counter-shapes 48 of the blade holder 14 and the body 12 by means of the fastening shapes 30 of the loading member 24. The wall 28 of the applied load member 24 has a curved cross section of more than 70% of the area, preferably more than 90% of the area. The loading member 24 is preferably a loading hose.

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V Typically, the loading member is pushed from the end of the blade holder and

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° between the frame. Removing the blade holder is a loading member

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£ 30 makes it quick and easy. For example, the blade holder can be removed for cleaning or completely replaced more quickly.

ίο The curved surface of the loading member does not collect dirt in the same way as o angular shapes. In addition, the curved surface is easier to clean

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over them. Also, the doctor blade 16 and / or the front plate 18 'can be changed 35 by lateral movement.

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In the scraping apparatus 10 according to the invention shown in Fig. 1, the loading member 24 has a substantially circular cross-section. Preferably, the load member at some point has a substantially circular load. Preferably, the loading member has a silicone structure, whereby it slides into place more easily. The loading member 24 is depressurized to disengage the doctor blade 16 from the roll surface 26. The forces coming from shrinking the loading member under reduced pressure are applied to the body and blade holder by opposing attachment designs. In addition, the fasteners-10 also hold the predominantly curved-wall loading member in place even when the loading member is pressurized.

There is a space 38 between the scraper blade 16 and the roll surface 26 between the blade holder 14 and the body 12, allowing the pivoting member 34 to be pivoted, and the loading member 24 on the opposite side of the pivotable connection 34 perpendicular to the blade blade. here the direction from the tip 31 of the doctor blade 16 to the base 33 of the doctor blade is indicated by the double-headed arrow 32.

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In the scraping apparatus 10 according to the invention shown in Fig. 1, the gap 38 between the scraper blade 16 and the roll surface 26 is formed between the roll surface 26 and the tip 31 of the scraper blade 16. Although the tip 31 is fixed to the roll surface, it is possible to talk between the scraper blade and the roll surface 25 38. When the scraper blade is in contact with the roll surface, the loading force of the scraper blade roller C 1 is adjusted between the scraper blade and the roll surface. The doctor blade 16 is attached to the blade holder 14, which is further supported by the frame member 12. In addition, the load securing member 24 is between the blade holder 14 and the frame member 12 so that the distance between the blade holder 14 and the frame member 12 is the coupling on its side of the load member 24 decreases under vacuum

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g load member 24. The joint 34 allows the blade holder 14 to rotate with respect to the body member 12. As the blade holder 14 rotates with respect to the body portion 12 ci j when the loading member 24 is depressurized, the scraper blade 16 35 disengages from the roll surface 26. In the scraping apparatus 10, the distance a between the blade holder 14 and 7 body 12 increases.

The support edge 18 of the scraper apparatus 10 may be a front plate 18 'which is securely locked to the blade holder 14 5 through which the load is directed to the doctor blade 16. According to the method of the invention, the support edge 18 can be profiled according to computational and / or measured width profile. The width profile as used herein refers to the width variation of the supporting edge 10 and / or the doctor blade along its length S, i.e. how the width parallel to the travel direction of the supporting edge and / or the fibrous web of the doctor blade changes parallel to the drive side.

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The support surface is profiled on its face against the doctor blade, i.e. preferably the profile is made on the bevel 17 of the front plate (Figure 1). The calculated and / or measured width profile is a prediction of the wear of the doctor blade of the doctoring apparatus, on the basis of which the supporting edge 20 is profiled. The calculated and / or measured width profile can be obtained, for example, from a worn scraper blade of a scraper apparatus, the width of which is utilized in the design of the scraper face front plate. The width profile 30 of the worn scraper blade is shown in Fig. 3. The geometry of the scraping position may also be taken into account in the calculation profile. For example, the effects of roll barrel and deflection of the scraper apparatus can be offset.

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° The width profile can be measured from worn, ie profiled

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£ 30 using known devices in the art of scraping steel, such as the applicant's prior art device under the trade name Bladeoo S Profile, which is disclosed in FI 111413. The device measures the wear of the scraper blade and draws on it a graph can be used directly for profiling the support edge 35 as a computed and / or measured width profile. The calculated or measured width profile can also be obtained from the width profile of the 8 rolls. For example, measuring a worn scraper blade provides a very accurate description of the width profile of a worn scraper blade, which facilitates the design and dimensioning of the profiling edge.

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As shown in Fig. 3, the width of the worn scraper blade in the scraper apparatus can vary considerably in the longitudinal direction S. The figures shown in Figures 3 and 4 are in millimeters. The width of the new non-abrasive doctor blade would be S 75 mm along its entire length 10, so that the doctor blade of Fig. 3 has been worn in the middle about 20 mm. From the width profile of the worn scraper blade, it can be directly interpreted where the surface pressure of the scraper apparatus on the rotating roller was too high. The narrower the worn scraper blade at a certain point, the more it has had surface pressure per roll and the more the supporting edge has to be profiled at that point to ensure that the new scraper blade is worn evenly.

According to the invention, a width profile is profiled on the support edge of the scraper apparatus on the basis of the calculated and / or measured width profile. According to the preferred embodiment shown in Figures 3 and 4, the face plate 32 'of Figure 4 is profiled based on the calculated and / or measured width profile 30 of Figure 3. most in the middle. In this way, the wear is compensated, while the blade pressure is evened out. The numbers on the vertical axis in Figure 4 indicate how much of the support edge

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° profiling at this point the length of the support edge S. The width profile of a fully x £ 30 non-profiled support would go in a straight cm line with a profiling depth of 0 at all times.

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o Profiling of the support edge can be performed e.g.

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with a period which is advantageous to perform as a machining technique. 35 In addition, the front plate can be detached from the blade holder, which greatly facilitates profiling the front plate. The front panel is removable 9 by pulling it sideways out of the blade holder, which makes changing it quick and easy.

According to a preferred embodiment, the front plate is profiled horizontally inverted with respect to the computed and / or measured width profile. Horizontally, due to the width profile of the inverted support edge, the doctor blade of the doctor blade follows the surface to be scraped, for example the width profile of the roll, so that the surface pressure between the doctor blade and the roll is uniform. This also results in a very good scraping result for the scraper equipment and even wear on the scraper blade.

When converting the support edge profile, a conversion factor of 15 is used between the calculated and / or measured width profile and the desired width profile, by which the dimensions in the pre-profile are converted to fit the support edge width profile. The conversion factor can be determined empirically by experimentation or based on past experience. The conversion factor may be, for example, 1/9 or 1/10, i.e., 1 cm of wear in the calculated and / or measured width pro-20 profile of the doctor blade corresponds to a profiling depth of 1 mm at the corresponding point of the support edge. The conversion factor should be set so that the support edge is not profiled too much, which would leave the scraper blade off the surface of the roll. This would significantly reduce the effectiveness of scraping.

The width profile of the support edge provided by the profiling of the support edge preferably extends over the entire width of the support edge. Profiled V shapes can only be a few millimeters in height -

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° size range, but this is enough to even out the wear of the doctor blade x £ 30. In addition, the small profiling depths in cm do not weaken the strength of the support edge. Scraper blade oo ίο bends under load to support width width profile, o δ

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The scraping apparatus according to the invention can be used in conjunction with disposable scraper blades or continuous gear scraper blades. The scraper apparatus may also be located in demanding positions of the fiber web machine, such as the breast roller. The supporting edge may be, for example, a front plate with rivets or the like.

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Claims (9)

A fiber web machine maker, comprising: (5) a blade (16), a blade holder (14) in which the blade (16) is arranged, and a front plate (18 ') mounted on the blade holder (14); forming a support edge (18) for transferring the load to the blade (16), the front plate (18 ') having a bevel (17), characterized in that the bevel (17') of the front plate (18 ') is profiled to achieve a uniform surface pressure . Creator apparatus according to claim 1, characterized in that the width profile (32) of said support edge (18) is in accordance with the width profile (30) of the calculated and / or measured creator blade (16). Creator apparatus according to claim 2, characterized in that the width profile (32) of said support edge (18) is profiled horizontally inversely in relation to the width profile (30) of the blade (16). Creator apparatus according to any one of claims 1-3, characterized in that said support edge (18) is a front plate CVJ (18 ') which is removably attached to the blade holder (14). in Ovi ° 5. Creator apparatus according to any of claims 1 - 4, x 30 characterized in that the blade holder (14) and the supporting edge (18) are made of fiber-reinforced plastic composite. CD m o o A method for adjusting the blade pressure of a fiber web machine's CJ J apparatus, according to which method the width profile is determined for a blade blade arranged in the blade holder, on the basis of which the blade pressure of the blade apparatus is adjusted, characterized in that the adjustment is carried out by profiling the blade guard 14. (18), which transfers the load from the blade holder (14) to the blade (16). 5 Process according to claim 6, characterized in that the supporting edge (18) is profiled by water cutting. Method according to claim 6 or 7, characterized in that as a support edge (18) a support edge is used according to any of claims 2-5. Method according to any of claims 6 to 8, characterized in that the width profile (30) of the cabinet blade (16) arranged in the blade holder (14) is determined by detaching the used blade from the cabinet apparatus (10) and measuring the wear by means of measuring devices. δ (M (M O X cc CL CM 00 CO m o δ CM