Device for supporting boiler

Abstract

The invention relates to a boiler (1) comprising a furnace (2). The furnace (2) comprises at least two end walls (3), at least two side walls (4), a furnace top (5) and a furnace bottom (6). The device further comprises at least one beam (7) extending in a depth direction (Dd). A beam (7) is located below the furnace floor (6) to support the furnace floor (6), the beam (7) being further located between the at least two side walls (4) and at a distance from each side wall (4). The ends (7a) of the beams (7) extend below the vertical portions (3a) of the at least two end walls (3). The device further comprises at least one rod (8) located between each end (7a) of the beam and a corresponding vertical portion (3a) of the end wall. The rod (8) is substantially vertical, the rod (8) being attached to an end (7a) of the at least one beam and a corresponding vertical portion (3a) of the end wall. Thereby, the rod (8) is arranged to transfer a load from the beam (7) to the vertical portion (3a) of the end wall.

Description

Technical Field

[0001] This invention relates to a boiler, and more particularly to a device for supporting the boiler. Background Technology

[0002] Boiler structures (such as those of circulating fluidized bed boilers) are typically very large and heavy. Therefore, boiler support requirements are high and important. Summary of the Invention

[0003] Therefore, the object of the present invention is to provide a novel device for supporting a boiler. This object is characterized by the contents of the independent claims. Some embodiments of the invention are disclosed in the dependent claims.

[0004] In the proposed solution, the boiler includes a furnace. The boiler can be, for example, a circulating fluidized bed boiler or a bubbling fluidized bed boiler. The furnace includes at least two side walls, at least two end walls, a furnace top, and a furnace bottom. The furnace may include two side walls and two end walls, such that the furnace has a rectangular horizontal cross-section having four corner portions. However, the furnace may also include more than two side walls and / or more than two end walls, such that the furnace has a polygonal horizontal cross-section having more than four corner portions. The distance between the at least two side walls defines the width of the furnace, the distance between the at least two end walls defines the depth of the furnace, and the direction between the at least two end walls is the depth direction. Each of the at least two end walls has a generally vertical portion and an inwardly sloping bottom portion, thereby the depth of the furnace at the bottom portion is less than the depth of the furnace at the vertical portion.

[0005] The proposed device also includes at least one beam extending in the depth direction. The beam is positioned below the furnace bottom to support it, and is also positioned between and at a distance from at least two sidewalls. The beam is longer than the depth of the furnace at the furnace bottom, and the ends of the beam extend below the vertical portions of at least two endwalls. The device also includes at least one rod located between each end of the beam and the corresponding vertical portion of the endwall. The rod is substantially vertical and is attached to the end of at least one beam and the corresponding vertical portion of the endwall. Thus, the rod is arranged to transfer the load from the beam to the vertical portion of the endwall. This arrangement provides simple and reliable support for the boiler. For example, it eliminates the need for baffles to support the furnace bottom inside the furnace. Furthermore, the inwardly sloping bottom portion of the endwall does not necessarily need to transfer at least substantially the load from the furnace bottom.

[0006] According to an embodiment, the device includes at least two rods located between the end of the beam and the corresponding vertical portion of the end wall. Thus, the load from the beam is effectively and uniformly transferred to the vertical portion of the end wall.

[0007] According to one embodiment, the upper portion of the rod is attached to the edge located between the vertical portion of the end wall and the inwardly sloping bottom portion of the end wall. Therefore, it is not necessary to transfer the load substantially across the edge, and the connection between the furnace structure and the edge can be very simple.

[0008] According to one embodiment, the ends of the beam are flatter than the rest of the beam. This provides space for the lower end of the rod and its fixing elements. Therefore, the ends of the rod do not extend at least substantially below the lowest part of the beam.

[0009] According to one embodiment, the ends of the beam are wider than the rest of the beam. This provides adequate space for attaching two or more rods to the ends of the beam if needed. Furthermore, widening the ends of the beam compared to the rest of the beam increases the stiffness of the ends.

[0010] According to one embodiment, the device includes a resilient element connected to the rod to allow thermal expansion between the rod and the furnace wall. Allowing for thermal expansion makes the structure more reliable. Furthermore, the rod can be positioned in an environment cooler than the furnace wall, and the rod can remain cool during boiler operation.

[0011] According to an embodiment, the elastic element includes a spring. Using a spring to form the elastic element provides a simple and reliable structure for the elastic element.

[0012] According to one embodiment, a rod is arranged to pass through the end of at least one beam. The device includes a support structure (such as a plate) at the lower end of the rod, and an elastic element is positioned between the support structure and the lower surface of the end of at least one beam. Thus, the lower end of the rod is connected or attached to the end of the beam in a simple and reliable manner.

[0013] According to an embodiment, the device includes a fastening rod located between the lower surface of the support structure and the end of the beam to limit the maximum distance between them. This prevents the elastic element from over-expanding and avoids lifting the end of the beam beyond permissible limits.

[0014] According to an embodiment, the device includes a support element located between the support structure and the lower surface of the beam end to limit the minimum distance between the support structure and the lower surface of the beam end. Thus, even very high loads on the beam will not compress the elastic element beyond the allowable limit of the support element. The support element maintains the minimum distance between the support structure and the lower surface of the beam end. Attached Figure Description

[0015] In the following description, the invention will be illustrated in more detail with reference to the accompanying drawings and some embodiments, in which...

[0016] Figure 1The diagram schematically shows the bottom portion of the boiler viewed from above at an angle;

[0017] Figure 2 schematically shown Figure 1 A partial side view of the bottom portion of the boiler, shown in cross-section;

[0018] Figure 3 schematically shown Figure 1 An end view of the bottom portion of the boiler;

[0019] Figure 4 schematically shown Figure 3 A magnified view of a portion of detail A in cross-section; and

[0020] Figure 5 The bottom portion of a boiler, viewed obliquely from above, is schematically shown according to another embodiment. Detailed Implementation

[0021] Figure 1 Boiler 1 is schematically shown. Boiler 1 may be, for example, a circulating fluidized bed boiler or a bubbling fluidized bed boiler. Boiler 1 includes a furnace 2. Furnace 2 includes two end walls 3, two side walls 4, a furnace top 5, and a furnace bottom 6. Figure 1 Only the bottom portion of boiler 1 is shown in general. However, the upper portion of boiler 1 and the furnace roof 5 are shown in... Figure 1 The figure is schematically shown in dashed lines. Boiler 1 may include additional equipment related to the boiler but not shown in the figure. This additional equipment may include, for example, the boiler and steam circulation system, flue gas passage, superheater, economizer, back pass, fly ash collection system, and one or more cyclone separators.

[0022] When the furnace 2 includes two end walls 3 and two side walls 4, the furnace 2 has a rectangular horizontal cross-section with four corner portions. However, the furnace 2 may also include more than two end walls 3 and / or more than two side walls 4, such that the furnace has a polygonal horizontal cross-section with more than four corner portions.

[0023] The distance between the side walls 4 defines the width W of the furnace 2. The distance between the end walls 3 defines the depth D of the furnace 2. The direction between the end walls 3 is the depth direction Dd. Typically, as shown, the width W of the furnace 2 is greater than the depth D of the furnace 2. However, in some embodiments, the width W of the furnace 2 can be almost equal to the depth D of the furnace 2, thereby providing the furnace 2 with an almost square horizontal cross-section. Typically, the width W of the furnace 2 is between 8 meters and 20 meters, the depth D of the furnace 2 is between 4 meters and 10 meters, and the height of the furnace 2 is between 15 meters and 40 meters.

[0024] The end wall 3 has a generally vertical portion 3a and an inwardly sloping bottom portion 3b. The depth D of the furnace 2 at the bottom portion 3b is less than the depth D of the furnace 2 at the vertical portion 3a. For example, this is in Figure 2 As clearly shown, an edge 3c is formed between the vertical portion 3a of the end wall 3 and the inwardly inclined bottom portion 3b of the end wall 3.

[0025] The boiler 1 also includes a beam 7 extending in the depth direction Dd. The beam 7 is positioned below the furnace bottom 6 to support the furnace bottom 6. The beam 7 may contact the furnace bottom 6 directly or indirectly. Indirect contact between the beam 7 and the furnace bottom 6 means that there is a solid structure (such as a beam) between the furnace bottom 6 and the beam 7.

[0026] The boiler 1 may also include one or more beams 18 extending in the width direction of the furnace 2. The one or more beams 18 may be attached to the lower end of the sidewall 4 via an attachment device 19. The attachment device 19 may include lugs, brackets, bolts, nuts, welds, and / or support beams, or any other suitable device for attaching the beam 18 to the lower end of the sidewall 4. In the embodiment shown in the figures, a beam 7 extending in the depth direction Dd is positioned below the beam 18 extending in the width direction. Thus, the beam 7 extending in the depth direction Dd prevents the beam 18 extending in the width direction from excessive bending.

[0027] A beam 7 extending in the depth direction Dd is positioned between and at a distance from each of the sidewalls 4. In the embodiment shown in the figure, the beam 7 extending in the depth direction Dd is positioned at the center of the furnace 2 in the width direction. The embodiment shown in the figure includes only one beam 7 extending in the depth direction Dd. However, the boiler 1 may also include two or more beams 7 extending in the depth direction Dd to support the furnace bottom 6.

[0028] The beam 7 extending in the depth direction Dd is longer than the depth D of the furnace 2 at the furnace bottom 6. The end 7a of the beam extends below the vertical portion 3a of the end wall 3.

[0029] A rod 8 exists between each end 7a of the beam and the corresponding vertical portion 3a of the end wall 3. The rod 8 is attached to the end 7a of the beam and the corresponding vertical portion 3a of the end wall 3. Thus, the rods 8 are arranged to transfer the load from the beam 7 to the vertical portion 3a of the end wall 3. The rods 8 can also be referred to as suspension rods because they hang from the end wall 3 and remain attached to the beam 7 extending in the depth direction Dd. The rods 8 do not need to be supported from below.

[0030] The rod is substantially vertical. "Substantially vertical" means that the rod 8 deviates from the vertical direction by less than 15 degrees. Preferably, the direction of the rod 8 is substantially the same as the direction of the vertical portion 3a of the end wall 3. Furthermore, according to an embodiment, the direction of the rod 8 is substantially the same as the direction of the vertical tube in the end wall 3.

[0031] The upper portion of rod 8 is attached to edge 3c located between the vertical portion 3a of the end wall and the inwardly sloping bottom portion 3b of the end wall. The upper portion of rod 8 can be attached to the end wall 3 using any device suitable for the attachment purpose. In the embodiment shown in the figures, the attachment devices include lugs 9, plates 10, bolts 11, and brackets 12. The bracket 12 is attached to the upper portion of rod 8, for example, by welding. The bracket 12 is attached to the plate 10, for example, by bolts 11. Multiple rods 8 can be attached to a single plate 10. The plate 10 can be attached to the end wall 3 using multiple lugs 9. The plate 10 can be attached to the lugs 9, for example, by welding. The lugs 9 can be attached to the end wall 3, for example, by welding.

[0032] The end wall 3 and the side wall 4 are formed in a conventional manner by a vertical tube 20 and fins welded between the vertical tube 20. Figure 3 A portion of some tubes 20 is schematically depicted. Lugs 9 may be welded to vertical tubes 20 and / or to fins between vertical tubes 20.

[0033] According to the embodiment shown in the figure, there are two rods 8 between the end 7a of the beam and the corresponding vertical portion 3a of the end wall. It is also possible that more than two rods 8 may be arranged between the end 7a of the beam and the corresponding vertical portion 3a of the end wall.

[0034] As from Figure 2 It is clear, for example, that the end 7a of the beam is flatter than the rest of the beam 7. Therefore, the height of the beam 7 at the end 7a is lower than the height of the rest of the beam 7. Consequently, the lowest end of the member 8 is not significantly lower than the lowest part of the beam 7.

[0035] The end 7a of the beam is wider than the rest of the beam 7. This provides adequate space for attaching two or more rods 8 to the end 7a of the beam if needed. Furthermore, making the end 7a wider than the rest of the beam 7 increases the stiffness of the end 7a of the beam.

[0036] The boiler 1 also includes an elastic element 13 connected to the rod 8 to allow thermal expansion between the rod 8 and the wall of the furnace 2. The elastic element 13 is positioned between the rod 8 and the end 7a of the beam. Specifically, during boiler 1 operation, the elastic element 13 allows the bottom portion 3b of the end wall to expand thermally more than the rod 8. Therefore, the rod 8 can be positioned in a cooler environment than the wall of the furnace 2, and the rod 8 can remain cool during boiler 1 operation.

[0037] exist Figure 4 Details of the elastic element 13 are shown. The elastic element 13 includes a spring 14. In one embodiment, the spring 14 is a cup spring.

[0038] The rod 8 is arranged to pass through the end 7a of the beam 7. Therefore, a through hole for the rod 8 exists in the beam 7. In the through hole, there is a gap between the rod 8 and the beam 7, such that the rod 8 and the beam 7 can move relative to each other in the axial direction of the rod 8 within the through hole.

[0039] At the lower end of the rod 8, there is a support structure such as plate 15. Plate 15 can be attached to the lower end of the rod 8 such that the plate is located on a nut 21 that is screwed around the threaded lower end of the rod 8.

[0040] Spring 14 is positioned around rod 8 and on plate 15. Thus, spring 14 extends between plate 15 and the lower surface of end 7a of beam. Therefore, the lower end of rod 8 is connected or attached to end 7a of beam in a simple and reliable manner.

[0041] A fastening rod 16 exists between the plate 15 and the lower surface of the beam end 7a. For example, the fastening rod 16 can be attached to the lower surface of the beam end 7a by welding. The fastening rod 16 can be arranged to pass through the plate 15. Therefore, a through hole for the fastening rod 16 can exist in the plate 15. In the through hole, a gap can exist between the fastening rod 16 and the plate 15, such that the fastening rod 16 and the plate 15 can move relative to each other in the axial direction of the fastening rod 16 within the through hole.

[0042] Spring 14 attempts to push the lower surfaces of plate 15 and beam end 7a further away from each other. However, at the lower end of fastening rod 16, plate 15 is attached to fastening rod 16 in a manner that prevents plate 15 from moving any lower relative to fastening rod 16. Therefore, this structure limits the maximum distance between plate 15 and the lower surface of beam end 7a. For example, a nut 22 may be present at the lower end of fastening rod 16 to prevent plate 15 from moving further away from the lower surface of beam end 7a. Thus, spring 14 cannot over-inflate and will not lift beam end 7a beyond the permissible level.

[0043] The lower end of the fastening rod 16 may be threaded. Thus, the nut 22 can be used to adjust the maximum distance between the plate 15 and the lower surface of the end 7a of the beam.

[0044] A sleeve 17 is attached to plate 15. Sleeve 17 is positioned around rod 8 and inside spring 14. However, sleeve 17 may also be positioned in other locations. The length of sleeve 17 is less than the maximum distance between plate 15 and the lower surface of end 7a of beam. It is also possible to attach sleeve 17 to the lower surface of end 7a of beam instead of attaching sleeve 17 to plate 15.

[0045] Sleeve 17 is a support element located between the supporting structure (such as plate 15) and the lower surface of the end 7a of the beam. Sleeve 17 defines a minimum distance between plate 15 and the lower surface of the end 7a of the beam. When the load on beam 7 becomes larger, it compresses spring 14. When the load is sufficiently high, the lower surface of the end 7a of the beam contacts the upper end of sleeve 17. Thus, sleeve 17 prevents beam 7 from moving further toward plate 15. Therefore, sleeve 17 maintains a minimum distance between plate 15 and the lower surface of the end 7a of the beam. Thus, even if the load on beam 7 is very high, spring 14 will not be compressed beyond the extent permitted by sleeve 17.

[0046] The length of sleeve 17 can be less than the maximum distance between plate 15 and the lower surface of end 7a of beam, such that the difference between the length of sleeve 17 and the maximum distance is equal to the difference between the thermal expansion of the furnace wall and rod 8. The difference between thermal expansion can be, for example, 5 mm to 30 mm.

[0047] After the thermal expansion of the wall has occurred, the load from beam 7 is rigidly transferred to rod 8. Furthermore, when sand accumulates in furnace 2, for example, spring 14 will not excessively yield, but the load is rigidly transferred from beam to sidewall 3 via beam.

[0048] Spring 14 is sized to withstand long-term loads. Spring 14 is never fully compressed because sleeve 17 prevents this. Furthermore, spring 14 is never released because fastening rod 16 prevents this. Fastening rod 16 keeps spring 14 in a slightly compressed state.

[0049] The end wall 3 transfers the load from the rod 8 upwards. The furnace 2 can be top-supported, whereby the furnace top 5 of the furnace 2 can be provided with beams and other supporting structures to support the furnace and transfer the load of the furnace 2 to other supporting structures. The furnace 2 can also be mid-supported.

[0050] Figure 5 Another embodiment of boiler 1 is shown. The lower portion of boiler 1 includes additional support structures 23 (such as beams) for supporting the end walls 3 and side walls 4. Otherwise, Figure 5 The scheme shown corresponds to Figures 1 to 4 The scheme shown is as follows.

[0051] It will be apparent to those skilled in the art that, with advancements in technology, the inventive concept can be realized in various ways. The present invention and its embodiments are not limited to the examples described above, but can be varied within the scope of the claims.

Claims

1. An apparatus for supporting a boiler, the apparatus comprising: Boiler (1), The boiler (1) includes: Stove (2), The furnace (2) includes: At least two end walls (3), At least two sidewalls (4), Furnace top (5), and Furnace bottom (6), The distance between the at least two side walls (4) defines the width (W) of the furnace (2), the distance between the at least two end walls (3) defines the depth (D) of the furnace (2), and the direction between the at least two end walls (3) is the depth direction (Dd). Each of the at least two end walls (3) has a generally vertical portion (3a) and an inwardly sloping bottom portion (3b), such that the depth (D) of the furnace (2) at the bottom portion (3b) is less than the depth (D) of the furnace (2) at the vertical portion (3a). The device further includes: At least one beam (7) extending along the depth direction (Dd), The at least one beam (7) is located below the furnace bottom (6) to support the furnace bottom (6). The at least one beam (7) is located between the at least two side walls (4) and is a distance away from each side wall (4). The at least one beam (7) is longer than the depth (D) of the furnace (2) at the furnace bottom (6), and The end (7a) of at least one beam extends below the vertical portion (3a) of at least two end walls (3), and At least one rod (8) is located between each end (7a) of the at least one beam and the corresponding vertical portion (3a) of the end wall. The rod (8) is basically vertical. The rod (8) is attached to the end (7a) of the at least one beam and the corresponding vertical portion (3a) of the end wall, and The rod (8) is arranged to transfer the load from the at least one beam (7) to the vertical portion (3a) of the end wall.

2. The apparatus according to claim 1, wherein, At each end (7a) of the at least one beam, there are at least two rods (8) located between the end (7a) of the at least one beam and the corresponding vertical portion (3a) of the end wall.

3. The apparatus according to claim 1 or 2, wherein, The upper part of the rod (8) is attached to the edge (3c) between the vertical part (3a) of the end wall and the inwardly inclined bottom part (3b) of the end wall.

4. The apparatus according to any one of the preceding claims, wherein, Rod (8) is a suspension rod.

5. The apparatus according to any one of the preceding claims, wherein, The end (7a) of the at least one beam is flatter than the rest of the at least one beam (7).

6. The apparatus according to any one of the preceding claims, wherein, The end (7a) of the at least one beam is wider than the rest of the at least one beam (7).

7. The apparatus according to any one of the preceding claims, wherein, The device includes an elastic element (13) connected to a rod (8) to allow thermal expansion between the rod (8) and the wall of the furnace (2).

8. The apparatus according to claim 7, wherein, The elastic element (13) includes a spring (14).

9. The apparatus according to claim 7 or 8, wherein, The rod (8) is arranged to pass through the end (7a) of the at least one beam, the device includes a support structure at the lower end of the rod (8), and an elastic element (13) is located between the support structure and the lower surface of the end (7a) of the at least one beam.

10. The apparatus according to claim 9, wherein, The device includes a fastening rod (16) located between the support structure and the lower surface of the end (7a) of the at least one beam to limit the maximum distance between the support structure and the lower surface of the end (7a) of the at least one beam.

11. The apparatus according to claim 9 or 10, wherein, The device includes a support element located between the support structure and the lower surface of the end (7a) of the at least one beam, to limit the minimum distance between the support structure and the lower surface of the end (7a) of the at least one beam.

12. The apparatus according to any one of the preceding claims, wherein, The boiler (1) is a fluidized bed boiler.

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