Operating components and devices for a drying section

Abstract

This invention relates to a running component for a drying section of a paper machine, a paperboard machine, etc., and an apparatus including the running component. The running component has an elongated box-shaped body having an inlet side surface and an outlet side surface. The inlet side surface includes at least one sealing element, and the outlet side surface is arranged at a horizontal distance from the inlet side surface. The running component also includes a lower surface and an upper surface. The lower surface extends from the inlet side surface to the outlet side surface and terminates at a first joint, and the upper surface extends from the inlet side surface to the outlet side surface and connects to the outlet side surface at a second joint. The outlet side surface of the running component includes a protruding, oblique shape having a main surface, the protruding, oblique shape being arranged closer to the first joint than the second joint.

Description

Technical Field

[0001] The present invention relates to a runnability component and arrangement for the drying section of a paper machine, a paperboard machine, etc. Background Technology

[0002] The drying section of a paper or paperboard machine includes heated drying cylinders, guide rolls, and running components. The drying cylinders are typically arranged parallel to each other at a first level, and the guide rolls are arranged parallel to each other at a second level. Pocket spaces are formed between every two adjacent drying cylinders and the guide rolls located between the cylinders. Running components are arranged within these pocket spaces. Running components are typically blow boxes or suction boxes, or they can provide both blowing and suction actions to stabilize the web. Typically, running components are elongated, box-like components, including hollow internal spaces and channels for necessary air transfer.

[0003] Operating components are used in the bag-like space to generate and maintain negative pressure, which helps keep the web to be dried in contact with the wire and improves the overall operability of the drying section. Operating components may include one or more air blowing devices, suction devices, one or more sealing members, and / or other structural features that help remove air from or prevent air from entering the bag-like space. Regardless of the existing operating components, there is a need to find a simple and effective way to generate and / or maintain improved negative pressure in the bag-like space. Mechanically uncomplicated solutions that are easy to construct and maintain are preferred. Summary of the Invention

[0004] One object of the present invention is to minimize or even completely eliminate the drawbacks of the prior art.

[0005] One objective is to provide an operational component and apparatus for generating and / or maintaining a high negative pressure in the bag-like space of a drying section.

[0006] Another object of the present invention is to provide an operational component that is not complicated to manufacture.

[0007] These objectives are achieved through the following scheme of the present invention.

[0008] The embodiments mentioned herein relate to all aspects of the invention, even if they are not always mentioned individually. Unless otherwise explicitly stated, different embodiments can be freely combined with each other.

[0009] A typical operating component of the drying section of a paper machine, paperboard machine, etc., according to the present invention has an elongated box-shaped body, said box-shaped body having:

[0010] -Inlet-side surface, including at least one sealing element,

[0011] - The outlet side surface is arranged at a horizontal distance from the inlet side surface.

[0012] - The lower surface extends from the inlet-side surface to the outlet-side surface and terminates at the first junction, and

[0013] - The upper surface extends from the inlet-side surface to the outlet-side surface and connects to the outlet-side surface at the second joint.

[0014] The outlet side surface includes a protruding deviation shape with a main surface, which is arranged closer to the first joint than the second joint.

[0015] A typical apparatus for a drying section of a paper machine, paperboard machine, etc., according to the present invention includes:

[0016] - The first drying cylinder and the second drying cylinder are arranged adjacent to each other at a first height.

[0017] - A guide roller, positioned at a second height in the space between the first and second drying cylinders.

[0018] The guide roller, the first drying cylinder, and the second drying cylinder define a bag-shaped space formed between the first and second drying cylinders and the guide roller.

[0019] - An operational component according to the invention is arranged in a bag-shaped space, wherein the outlet side of the operational component includes a protruding oblique shape having a main surface and is arranged facing a second drying cylinder, wherein the distance between the second drying cylinder and the main surface of the protruding oblique shape is at most 40 mm, preferably at most 30 mm.

[0020] It has now been unexpectedly discovered that air removal from the bag space can be more effectively achieved by arranging the protruding skew shape on the lower part of the outlet-side surface of the running component. The protruding skew shape is simple in construction, provides unexpectedly effective functionality, and is applicable to many different drying sections, even in existing paper and paperboard machines. When the running component according to the invention is installed in the bag space, the main surface of the protruding skew shape is arranged close to the second drying cylinder. This creates a narrow channel between the main surface of the protruding skew shape and the second drying cylinder. During the drying operation of the paper web or paperboard web, the web and support wire move through the narrow channel, where the distance between the second drying cylinder and the main surface of the protruding skew shape is at most 40 mm, preferably at most 30 mm. Air flows freely through the protruding skew shape, and the air removal from the bag space is enhanced and accelerated because the air boundary layer associated with the moving wire facilitates the movement of air in the narrow channel and away from the bag space. Improved air removal reduces suction through the guide rollers and saves overall energy consumption of the running component.

[0021] In this article, high negative pressure means low absolute pressure, and low negative pressure means high absolute pressure. Negative pressure refers to pressure that is approximately 1 bar (i.e., 100 kPa) below normal atmospheric pressure.

[0022] According to the invention, the protruding deflection shape is arranged closer to the first joint, the lower surface of the running component terminates at the first joint, and the lower portion connects from the first joint to the outlet side surface, i.e., at the lower portion of the outlet side surface. The protruding deflection shape preferably forms an integral structural portion of the outlet side surface, i.e., the protruding deflection shape cannot be separated from the outlet side surface. Preferably, the protruding deflection shape is arranged to be immovable and has no spring or other corresponding elasticity-providing device.

[0023] According to one embodiment, apart from the protruding skew shape, the outlet side of the running component preferably has no other protruding shape or flow restriction device, such as scraper blades, air knives, or air nozzles.

[0024] The protruding skew shape can be formed by machining the material on the outlet side surface into the desired protruding shape (e.g., by folding or bending). It has been observed that forming a protruding skew shape from the material on the outlet side surface can increase and improve the structural rigidity of the running component, and thus reduce the risk associated with bending the running component during drying operations. Furthermore, the protruding skew shape can increase the internal volume of the running component, providing more space for flow channels and / or other internal components.

[0025] For example, based on available processing techniques and / or desired functional effects, the protruding skew shape can have any suitable form, and the shape can be freely chosen. The protruding skew shape has at least a main surface arranged in a bag-like space facing the second drying cylinder. The protruding skew shape or its main surface can be curved, can include at least one planar surface portion, can be formed smoothly, and / or can be formed in an alternating or stepped manner.

[0026] Preferably, the main surface of the protruding oblique shape includes at least one flat surface portion. It has been observed that when the protruding oblique shape has a flat surface portion, it is easy to create a narrow channel of suitable length and shape, said narrow channel being formed between the protruding oblique shape and the second drying cylinder. According to one embodiment of the invention, the flat surface portion of the protruding oblique shape can extend 100 mm to 200 mm, preferably 120 mm to 150 mm, in the direction from the first joint to the second joint. It has been observed that this length of the flat surface portion provides effective air removal from the bag-like space.

[0027] Typically, the outlet-side surface of the operating component includes a major surface portion between the second joint and the protruding slant shape. This major surface portion is generally smooth and substantially planar, extending from the second joint to a first inflection point, at which the protruding slant shape begins to protrude from the major surface portion. Viewed along the outlet-side surface from this inflection point to the second joint, the distance between the second joint and the first inflection point, i.e., the length of the major surface portion, can be from 100 mm to 350 mm, preferably from 200 mm to 300 mm. Between the second joint and the inflection point, the distance between the inlet-side surface and the outlet-side surface generally increases in this direction, indicating that the planar major surface portion is generally slanted.

[0028] In some embodiments, the flat main surface portion on the outlet side is continuous in a uniplanar fashion on both sides of the protruding oblique shape. This means that a first portion of the main surface portion is located between the second joint and the first inflection point (as described above), and a second portion of the main surface portion is located between the first joint and the second inflection point. The first portion of the main surface portion is longer than the second portion of the main surface portion. The second portion of the main surface portion may be directly connected to the first joint or connected to the first joint via an intermediate surface.

[0029] According to a preferred embodiment, the protruding slant shape is located near the first joint, such that the main surface portion is discontinuous between the second inflection point and the first joint, but the protruding slant shape and the first joint are directly connected to each other or connected to each other through a second intermediate surface. The second intermediate surface is preferably flat and forms an obtuse angle between the main surface and the second intermediate surface.

[0030] The protruding deflection shape can protrude from the surface plane defined by the main surface portion of the exit side surface by up to 30 mm to 70 mm, preferably 45 mm to 55 mm. This means that the difference between the surface plane defined by the main surface portion and the parallel deviation plane is in the range of 30 mm to 70 mm, preferably in the range of 45 mm to 55 mm, wherein the parallel deviation plane is set through the farthest point of the surface protruding the deflection shape.

[0031] When the main surface of the protruding oblique shape includes at least one flat surface portion, the flat surface portion and the main surface portion of the outlet side surface are substantially arranged in different planes. The main surface portion and the flat surface portion can be arranged in parallel planes or at an angle relative to each other. According to a preferred embodiment, the flat surface portion of the protruding oblique shape and the main surface portion of the outlet side surface are arranged in parallel planes.

[0032] When arranged in a bag-like space, the distance between the drying net and the flat surface portion of the protruding, skewed shape can preferably be constant. The running components can be arranged such that the protruding, skewed shape is preferably located entirely below the point of tangency where the net meets the surface of the second drying cylinder.

[0033] According to another preferred embodiment, when viewed along the outlet side surface in the direction from the first joint to the second joint, the distance between the surface plane defined by the main surface portion and the flat surface portion changes. In other words, the main surface portion and the flat surface portion can be arranged at an angle relative to each other. The angle between the surface plane defined by the main surface portion and the plane of the flat surface portion can be, for example, in the range of 145° to 175°.

[0034] When the main surface portion and the flat surface portion are arranged at an angle relative to each other, the distance between the flat surface portion and the mesh varies along the length of the flat surface portion towards the inflection point. This distance can be reduced, thereby emphasizing that the channel between the skewed shape and the mesh widens in the direction of mesh movement, or the distance can be increased, thereby emphasizing that the channel between the skewed shape and the mesh narrows in the direction of mesh movement. Preferably, the distance is reduced, i.e., the channel widens in the direction of mesh movement.

[0035] The main surface with a prominent skewed shape can be directly connected to the main surface portion at the inflection point, or the flat surface portion of the main surface and the main surface portion can be connected through a first intermediate surface, preferably through a flat intermediate surface.

[0036] In the context of this invention, the running component may be an air-blowing box and / or a suction box. In either case, the running component has an elongated box-shaped body, which may be formed of any suitable metal (such as aluminum or steel). The running component has an inlet-side surface, an outlet-side surface, an upper surface, and a lower surface. The lower and upper surfaces are arranged to engage or connect the inlet-side and outlet-side surfaces at a first engagement and a second engagement. The lower surface of the running component is the surface of the running component closest to the guide roller in the bag-like space and is arranged substantially towards the guide roller. According to one embodiment, at least one mechanical sealing element (such as a labyrinth seal) may be arranged on the lower surface of the running component to restrict and / or prevent air flow from the outlet side to the inlet side and vice versa. The point where the lower surface terminates on the outlet side is designated as the first engagement. Typically, the first engagement constitutes an angle at which the planar orientation of the surface of the running component changes.

[0037] In the apparatus according to the invention, the inlet-side surface of the operating component is arranged to face the first drying cylinder. The inlet-side surface of the operating component includes at least one sealing element arranged to discharge air from the bag-like space and / or prevent air from entering the bag-like space. The sealing element on the inlet-side surface can be a blowing element, a suction element, a mechanical seal element, or any combination of one or more of these elements. For example, the inlet-side surface of the operating component may include a blowing element and one or more mechanical seal elements such as sealing strips and / or labyrinth seals.

[0038] The outlet-side surface of the operating component is arranged to face the second drying cylinder. The outlet-side surface is preferably continuous, i.e., it has no suction element, blowing element and / or sealing element.

[0039] According to the invention, the running components are arranged in a bag-shaped space defined by a first drying cylinder and a second drying cylinder, and a guide roller between them. The first and second drying cylinders are parallel, i.e., their longitudinal axes are parallel to each other, and they are arranged at a distance from each other. Adjacent drying cylinders are arranged horizontally at a first height, and the guide roller is arranged between two adjacent drying cylinders such that the longitudinal axis of the guide roller is substantially parallel to the longitudinal axes of the first and second drying cylinders, but at a second height in the vertical direction. Thus, the guide roller is arranged at a height higher or lower than the first and second drying cylinders, typically at a lower height. Furthermore, the guide roller is positioned between the drying cylinders such that its surface does not contact the surface of the drying cylinders, i.e., it does not contact the surface of the drying cylinders. In a typical paper or paperboard machine, the box-shaped running components, drying cylinders, and guide roller are elongated in the transverse direction of the machine, and they extend substantially over the entire width of the web run. Therefore, the bag-shaped space defined by them is also elongated in the transverse direction of the paper machine. The distance between the first and second ends of the elongated box-shaped body of the operating component can be 5m to 15m, preferably 8m to 12m. The ends of the bag-shaped space are typically sealed, for example, by means of end plates (such as gap plates) according to the prior art. At both ends of the bag-shaped space, vertical end plates are arranged in the machine direction.

[0040] The apparatus according to the invention may preferably include a drying net extending from a first drying cylinder to a second drying cylinder via the outer surface of a guide roller. The drying net supports the web to be dried and forms the web together with the web. Viewed in the direction of movement of the drying net, the channel formed between the drying net and the main surface with the protruding oblique shape may preferably have a length in the range of 100 mm to 200 mm, and more preferably in the range of 120 mm to 150 mm. According to one embodiment of the invention, the distance between the drying net and the main surface with the protruding oblique shape is in the range of 10 mm to 40 mm, and more preferably in the range of 20 mm to 30 mm.

[0041] At the location where the drying net extends to the second drying cylinder, a closed pressure zone is formed between the drying net and the second drying cylinder. The operational components can preferably be arranged in the bag-like space such that the protruding, skewed shape is located before the closed pressure zone.

[0042] The running components and apparatus of the present invention are particularly suitable for the drying section of paper machines or paperboard machines. The running components are particularly suitable for paper machines or paperboard machines with wire speeds greater than 1000 m / min, preferably greater than 1200 m / min, and more preferably greater than 1500 m / min. Attached Figure Description

[0043] Non-limiting examples of the invention are presented in more detail in the following schematic diagrams, wherein

[0044] Figure 1 An apparatus for a drying section of a paper machine, a paperboard machine, etc., according to an embodiment of the present invention is shown. Detailed Implementation

[0045] Figure 1 An apparatus according to an embodiment of the present invention is shown. The apparatus 100 includes a first drying cylinder 2 and a second drying cylinder 3. The drying cylinders 2 and 3 are arranged horizontally adjacent to each other such that their longitudinal axes (not shown) are parallel to each other and are arranged at a first height. A guide roller 4 is arranged at a second height in the space between the drying cylinders 2 and 3. A bag-shaped space 5 is formed between the first drying cylinder 2, the second drying cylinder 3, and the guide roller 4, and a running component 1 is arranged in the bag-shaped space 5.

[0046] The operating component 1 has an elongated box-shaped body 10. The body 10 of the operating component 1 has an inlet-side surface 11, an outlet-side surface 12, a lower surface 13, and an upper surface 14. The inlet-side surface 11 includes at least one sealing element 15, which is arranged toward the first drying cylinder to restrict airflow into and out of the bag-shaped space 5. Another sealing element 15' is arranged to connect with the lower surface 13 of the body 10 of the operating component 1. The sealing element 15' is designed to prevent air from flowing from the outlet side of the bag-shaped space 5 to the inlet side of the bag-shaped space 5. The inlet-side surface 11 of the operating component 1 may include other sealing elements (such as a sealing nozzle 16) designed to exhaust air from the bag-shaped space 5 and prevent air from entering the bag-shaped space 5. The rotation directions of the drying cylinders 3 and 4 are indicated by arrows A and B.

[0047] The lower surface 13 of the operating component 1 extends between the inlet-side surface 11 and the outlet-side surface 12, and terminates at the first joint 20. Similarly, the upper surface 14 extends between the inlet-side surface 11 and the outlet-side surface 12, and connects to the outlet-side surface 12 at the second joint 21.

[0048] The outlet-side surface 12 of the operating component 1 includes a main surface portion 12' and a protruding oblique shape 17 having a main surface 17'. On the outlet-side surface 12, the oblique shape 17 is arranged closer to the first joint 20 than the second joint 21, meaning that in the direction of movement of the net 6, the main surface portion 12' is located behind the oblique shape 17 on the outlet side. The length of the main surface portion 12' is... Figure 1 As indicated by arrow II. The length can be, for example, 100 mm to 350 mm. The main surface 17' and main surface portion 12' of the skewed shape 17 can be connected by the first intermediate surface 18. The skewed shape 17 is directly connected to the first joint 20 by the second intermediate surface 19.

[0049] The main surface 17' of the skew shape 17 is arranged facing the second drying cylinder 3, at a relatively close distance from the surface of the second drying cylinder 3. Therefore, a narrow channel is formed between the main surface 17' of the skew shape 17 and the second drying cylinder 3. A fiber web (such as a paper web) supported by the wire 6 is arranged to extend from the guide roller 4 to the second drying cylinder 3 through the narrow channel. The direction of movement of the web / wire is indicated by arrow C. The distance between the second drying cylinder 3 and the main surface 17' of the skew shape 17, i.e., the width of the narrow channel, is... Figure 1 The distance is indicated by arrow III-III. Typically, this distance is at most 40 mm, preferably at most 30 mm.

[0050] exist Figure 1 In the embodiment presented, the main surface 17' of the skewed shape 17 has a flat surface portion, such as Figure 1 As indicated, the flat surface portion extends by a length D. Typically, when viewed from the first joint 20 to the second joint 21 on the outlet-side surface 12, the length D of the flat portion can be 100 mm to 200 mm, preferably 120 mm to 150 mm. Figure 1 It can also be seen that the flat surface portion of the main surface 17' can be arranged in a plane parallel to the main surface portion 12' of the outlet side surface 12, or the main surface 17' of the oblique shape 17 and the main surface portion 12' of the outlet side surface 12 can be arranged at an angle relative to each other. Figure 1 The dashed lines in the diagram illustrate two possibilities for the following embodiments. When the main surface portion 12' and the flat surface portion 17' are arranged at an angle relative to each other, the narrow channel formed between the flat surface portion 17' and the mesh 6 can become wider or narrower in the direction of mesh movement.

[0051] The tangent point of drying cylinders 2 and 3 is indicated by the dashed line T. At the tangent point, the mesh separates from or meets the surface of drying cylinders 2 and 3. The running component 1 is arranged in the bag-shaped space 5 such that the flat surface portion of the protruding oblique shape 17 is located below the tangent point on the surface of the second drying cylinder 3.

[0052] exist Figure 1 A conventional gap plate is schematically shown in the diagram using dashed lines. Furthermore, the air passage within the operational component 1 is schematically shown.

[0053] Even though the invention has been described with reference to what appears to be the most practical and preferred embodiments, it should be understood that the invention is not limited to the embodiments described above, but is intended to also cover different modifications and equivalents within the scope of the appended claims.

Claims

1. A running component for the drying section of a paper machine or paperboard machine, the running component having an elongated box-shaped body, the box-shaped body having: - The inlet-side surface includes at least one sealing element. - An outlet-side surface, arranged at a horizontal distance from the inlet-side surface, wherein... The outlet side surface has a main surface portion. - The lower surface, extending from the inlet-side surface to the outlet-side surface, and terminating at the first joint, and - An upper surface that extends from the inlet-side surface to the outlet-side surface and connects to the outlet-side surface at the second joint. Its features are, The outlet side surface includes a protruding oblique shape having a main surface, the protruding oblique shape being arranged closer to the first joint rather than the second joint; The protruding, skewed shape protrudes 30-70 mm from the surface plane defined by the main surface portion; Between the second joint and the first inflection point where the protruding oblique shape begins to protrude from the main surface portion, the distance between the inlet-side surface and the outlet-side surface increases; The outlet side surface is not provided with suction elements, air blowing elements and / or sealing elements.

2. The operational component according to claim 1, characterized in that, The protruding skew shape protrudes 45 mm to 55 mm from the surface plane defined by the main surface portion.

3. The operational component according to claim 1, characterized in that, The main surface of the protruding, skewed shape includes at least one flat surface portion.

4. The operational component according to claim 3, characterized in that, Viewed in the direction from the first joint to the second joint, the flat surface portion of the protruding oblique shape extends from 100 mm to 200 mm.

5. The operational component according to claim 4, characterized in that, The flat surface portion of the protruding, skewed shape extends from 120 mm to 150 mm.

6. The operational component according to any one of claims 3 to 5, characterized in that, The main surface portion and the flat surface portion are arranged in parallel planes.

7. The operational component according to any one of claims 3 to 5, characterized in that, The main surface portion and the flat surface portion are arranged at an angle relative to each other.

8. The operational component according to claim 7, characterized in that, The angle between the surface plane defined by the main surface portion and the plane defined by the flat surface portion is in the range of 145° to 175°.

9. The operational component according to any one of claims 3 to 5, characterized in that, The main surface with the protruding skewed shape is directly connected to the main surface portion at the inflection point, or the flat surface portion of the main surface and the main surface portion are connected through a first intermediate surface.

10. The operational component according to any one of claims 1 to 5, characterized in that, From the inflection point to the second joint, the length of the main surface portion is 100mm to 350mm.

11. The operational component according to claim 10, characterized in that, The length of the main surface portion from the inflection point to the second joint is 200 mm to 300 mm.

12. An apparatus for a drying section of a paper machine or a paperboard machine, comprising: - The first drying cylinder and the second drying cylinder are arranged adjacent to each other at a first height. - A guide roller, positioned at a second height in the space between the first drying cylinder and the second drying cylinder. The guide roller, the first drying cylinder, and the second drying cylinder define a bag-like space formed between the first drying cylinder and the second drying cylinder and the guide roller. - An operational component according to any one of claims 1 to 11, arranged in the bag-shaped space, wherein the outlet side of the operational component includes a protruding oblique shape having a main surface and is arranged facing the second drying cylinder. Its features are, The distance between the second drying cylinder and the main surface of the protruding oblique shape is at most 40 mm.

13. The apparatus according to claim 12, characterized in that, The device includes a drying screen that extends from the first drying cylinder to the second drying cylinder via the deflector roller, wherein, viewed in the direction of movement of the drying screen, a channel is formed between the drying screen and the main surface of the protruding oblique shape, the channel having a length in the range of 100 mm to 200 mm.

14. The apparatus according to claim 13, characterized in that, The distance between the drying mesh and the main surface with the protruding oblique shape in the channel is in the range of 10 mm to 40 mm.

15. The apparatus according to claim 13 or 14, characterized in that, The distance between the drying mesh and the main surface of the protruding skew shape in the channel is constant.

16. The apparatus according to claim 13 or 14, characterized in that, The channel between the main surface with the protruding skew shape and the second drying cylinder is arranged to widen in the direction of movement of the mesh.

17. The apparatus according to claim 13 or 14, characterized in that, The protruding skewed shape is located below the point of tangency where the drying mesh meets the surface of the second drying cylinder.

18. The apparatus according to claim 12, characterized in that, The distance between the second drying cylinder and the main surface of the protruding oblique shape is at most 30 mm.

19. The apparatus according to claim 13, characterized in that, The channel has a length ranging from 120mm to 150mm.

20. The apparatus according to claim 14, characterized in that, The distance between the drying mesh and the main surface with the protruding oblique shape in the channel is in the range of 20 mm to 30 mm.

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