Elastic supporting structure of heat preservation and insulation layer in steel chimney

Abstract

The invention discloses an elastic supporting structure for heat preservation and insulation layers in a steel chimney, the steel chimney comprises an upper steel chimney section and a lower steel chimney section, heat preservation and insulation layers are arranged on the inner wall of the upper steel chimney section and the inner wall of the lower steel chimney section, and an annular supporting base is arranged between the heat preservation and insulation layers of the upper steel chimney section and the lower steel chimney section. The heat preservation and insulation layer of the upper section of steel chimney is supported on the top of the annular supporting base, the outer wall of the annular supporting base is fixedly connected with the inner wall of the steel chimney, and a connecting flange for connecting the upper section of steel chimney and the lower section of steel chimney together is arranged on the outer cylinder wall at the joint of the upper section of steel chimney and the lower section of steel chimney. An uncompressed refractory fiber felt is arranged between the bottom of the annular supporting base and the top of the heat preservation and insulation layer of the lower section of steel chimney, and a compressed refractory fiber felt is arranged between the top of the annular supporting base and the bottom of the heat preservation and insulation layer of the upper section of steel chimney. The problems that a traditional heat preservation layer is prone to falling off, heat stress is concentrated, and installation is complex are solved. And the times of shutdown inspection and replacement and maintenance caused by falling of the thermal insulation layer are reduced.

Description

Technical Field

[0001] The invention relates to an elastic supporting structure of a heat preservation and insulation layer in a steel chimney, belonging to the technical field of industrial chimney structures. Background Art

[0002] Traditional steel chimney insulation layers are often fixed with welded anchors or straps. This fixing method has the following problems: 1. Rigid connection causes the insulation layer to crack or fall off easily during thermal expansion and contraction; 2. Welded connection easily damages the anti-corrosion coating of the steel chimney, thereby accelerating the corrosion of the steel chimney; 3. The installation process of using welded anchors or straps for fixing is complicated, and later maintenance is difficult. Therefore, it is a technical problem that the industry urgently needs to solve to involve a thermal insulation layer support structure that can adapt to thermal deformation, reduce thermal bridge effects, and is easy to construct, improve the heat resistance temperature of the chimney, and extend the service life of the chimney. Summary of the invention

[0003] The purpose of the present invention is to provide an elastic support structure for the thermal insulation layer in a steel chimney, which can adapt to thermal deformation, reduce thermal bridge effect, and facilitate construction, thereby not only improving the heat resistance temperature of the chimney, but also extending the service life of the chimney.

[0004] The technical solution of the present invention is as follows: an elastic supporting structure of a thermal insulation layer in a steel chimney, wherein the steel chimney comprises an upper steel chimney section and a lower steel chimney section which are adjacently arranged, the inner walls of the upper steel chimney section and the lower steel chimney section are both provided with a thermal insulation layer, an annular support base is provided between the thermal insulation layers of the upper steel chimney section and the lower steel chimney section, the thermal insulation layer of the upper steel chimney section is supported on the top of the annular support base, the outer wall of the annular support base is fixedly connected to the inner wall of the steel chimney, a connecting flange for connecting the upper steel chimney section and the lower steel chimney section is provided on the outer cylinder wall at the joint of the upper steel chimney section and the lower steel chimney section, an uncompressed refractory fiber felt is provided between the bottom of the annular support base and the top of the thermal insulation layer of the lower steel chimney section, and a compressed refractory fiber felt is provided between the top of the annular support base and the bottom of the thermal insulation layer of the upper steel chimney section; The top surface of the annular support base is provided with a single-layer annular stiffening rib, the middle of which is provided with a double-layer annular stiffening rib, and compressed refractory fiber felt is provided between the middle double-layer annular stiffening ribs, the center line of the refractory fiber felt is just in the same plane as the end surface of the joint of the upper steel chimney and the lower steel chimney, and the end of the annular stiffening rib is welded and fixed to the inner wall of the steel chimney; A plurality of vertical stiffening ribs are arranged in a circular manner inside the annular support base.

[0005] In the aforementioned elastic support structure of the thermal insulation layer in a steel chimney, an upward convex ring is provided on the inner side of the top end of the annular support base, which wraps the lower end of the outer wall of the thermal insulation layer of the upper section of the steel chimney, and uncompressed refractory fiber felt is arranged between the convex ring and the thermal insulation layer.

[0006] In the aforementioned elastic support structure for the thermal insulation layer in a steel chimney, the thickness of the annular support base is at least 200 mm greater than the thickness of the thermal insulation layer; and the height of the convex ring is ≥200 mm.

[0007] In the aforementioned elastic support structure of the thermal insulation layer inside a steel chimney, the vertical stiffening ribs are provided with two layers, which are respectively arranged in the upper and lower annular support bases with the plane at the joint of the upper steel chimney and the lower steel chimney as the boundary, and the outer side surfaces of the vertical stiffening ribs are welded and fixed to the inner wall of the steel chimney.

[0008] In the aforementioned elastic support structure of the thermal insulation layer in a steel chimney, the annular support base is cast by refractory castables, and a radial and annular steel mesh is arranged inside the refractory castables. The ends of the radial and annular steel mesh are welded and fixed to the inner wall of the steel chimney.

[0009] Beneficial effects of the invention: Compared with the prior art, the invention adopts the above technical solution to form a thermal insulation layer support structure that can adapt to thermal deformation, reduce thermal bridge effect, and is easy to construct. It can be combined with the actual needs of the project to focus on solving the problems of easy shedding of the traditional thermal insulation layer, concentrated thermal stress, and complex installation. Reduce the number of shutdown inspections and replacement repairs caused by the fall of the thermal insulation layer. It is suitable for high-temperature chimneys such as graphitization and power plants (flue gas temperature> 600°C), especially suitable for high-humidity corrosive environments along the coast. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a plan view of the connection between the upper and lower sections of the steel chimney; Figure 3 for Figure 2 Schematic cross-section diagram of .

[0011] Figure numerals: 1-upper section of steel chimney, 2-lower section of steel chimney, 3-thermal insulation layer, 4-annular support base, 5-connecting flange, 6-refractory fiber felt, 7-convex ring, 8-annular stiffening rib, 9-vertical stiffening rib, 10-refractory castable, 11-radial annular steel mesh. DETAILED DESCRIPTION

[0012] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0013] An embodiment of the present invention: An elastic supporting structure for a thermal insulation layer in a steel chimney, the steel chimney comprising an upper steel chimney section 1 and a lower steel chimney section 2 which are adjacently arranged, the inner walls of the upper steel chimney section 1 and the lower steel chimney section 2 are both provided with a thermal insulation layer 3, an annular support base 4 is provided between the thermal insulation layer 3 of the upper steel chimney section 1 and the lower steel chimney section 2, the annular support base 4 is arranged inside the steel chimney, the thermal insulation layer 3 of the upper steel chimney section 1 is supported on the top of the annular support base 4, the outer wall of the annular support base 4 is fixedly connected to the inner wall of the steel chimney to prevent the annular support base 4 from pressing on the thermal insulation layer 3 of the lower steel chimney section 2, and a connecting flange 5 is provided on the outer cylinder wall at the joint of the upper steel chimney section 1 and the lower steel chimney section 2, and the upper steel chimney section 1 and the lower steel chimney section 2 can be fixedly connected together by bolts passing through the connecting flanges 5 of the two. An uncompressed refractory fiber felt 6 is arranged between the bottom of the annular support base 4 and the top of the thermal insulation layer 3 of the lower steel chimney 2, while a compressed refractory fiber felt 6 is arranged between the top of the annular support base 4 and the bottom of the thermal insulation layer 3 of the upper steel chimney 1.

[0014] Among them, when the thermal insulation layer 3 of the lower section steel chimney 2 is completed, a gap of 20 mm is left between the bottom of the annular support base 4 and the thermal insulation layer 3 of the lower section steel chimney 2, and the gap is used to fill the uncompressed refractory fiber felt 6. Since the annular support base 4 is fixed on the inner wall of the steel chimney, the refractory fiber felt 6 at the bottom of the annular support base 4 and the top of the thermal insulation layer 3 of the lower section steel chimney 2 will not be compressed by the annular support base 4. Since the refractory fiber felt 6 is provided, the gap between the thermal insulation layer 3 and the bottom of the annular support base 4 can be filled. At the same time, since the refractory fiber felt 6 is not compressed, it has a certain elasticity. When the thermal insulation layer 3 of the lower section steel chimney 2 is heated and expanded, the refractory fiber felt 6 provides the thermal insulation layer 3 with a certain expansion and deformation space. When the thermal insulation layer 3 cools and shrinks, the refractory fiber felt 6 can fill the gap and achieve sealing.

[0015] A compressed refractory fiber felt 6 is arranged between the top of the annular support base 4 and the bottom of the thermal insulation layer 3 of the upper steel chimney 1. After the refractory fiber felt 6 is arranged, the thermal insulation layer 3 of the upper steel chimney 1 needs to be built on it. Since the refractory fiber felt 6 is compressed, the thermal insulation layer 3 can be guaranteed to be stable. At the same time, the refractory fiber felt 6 can fill the gap between the annular support base 4 and the thermal insulation layer 3 of the upper steel chimney 1 to achieve sealing. The annular support base 4 is fixed on the inner wall of the steel chimney, so it can support the thermal insulation layer 3 of the upper steel chimney 1.

[0016] An upward convex ring 7 is provided on the inner side of the top end of the annular support base 4, and the convex ring 7 wraps the lower end of the outer wall of the thermal insulation layer 3 of the upper steel chimney 1. An uncompressed refractory fiber felt 6 is provided between the convex ring 7 and the thermal insulation layer 3. The inner side of the thermal insulation layer 3 can be protected and sealed by the convex ring 7, and the compressed refractory fiber felt 6 can fill the gap between the two to ensure the sealing performance, and the side of the thermal insulation layer 3 can be well supported and protected by the convex ring 7, while giving the thermal insulation layer 3 a certain expansion and deformation space after heating.

[0017] The thickness of the annular support base 4 is at least 200 mm greater than the thickness of the thermal insulation layer 3, so that the annular support base 4 has a better fire protection effect. The height of the convex ring 7 is ≥ 200 mm, so that the convex ring 7 has a better protective sealing effect.

[0018] The top surface of the annular support base 4 is provided with a single-layer annular stiffening rib 8, and the middle part is provided with a double-layer annular stiffening rib 8. A compressed refractory fiber felt 6 is provided between the middle double-layer annular stiffening ribs 8. The center line of the refractory fiber felt 6 is just in the same plane as the end face of the joint of the upper steel chimney 1 and the lower steel chimney 2. The end of the annular stiffening rib 8 is welded and fixed to the inner wall of the steel chimney. The annular stiffening rib 8 can enhance the structural strength of the annular support base 4. The reason why the middle part is provided with a double-layer annular stiffening rib 8 is mainly to clamp and fix the middle refractory fiber felt 6 by two annular stiffening ribs 8. The refractory fiber felt 6 is mainly used to seal the joint gap between the upper steel chimney 1 and the lower steel chimney 2. At the same time, since the annular support base 4 will not be deformed when heated, the compressed refractory fiber felt 6 is provided between the double-layer annular stiffening ribs 8, which can better achieve sealing. The end of the annular stiffening rib 8 is welded and fixed to the inner wall of the steel chimney, and the annular stiffening rib 8 is fixedly connected to the annular support base 4, so that the annular support base 4 is better connected and fixed to the steel chimney.

[0019] A plurality of vertical stiffening ribs 9 are arranged in a ring shape inside the annular support base 4 to improve the structural strength of the annular support base 4 .

[0020] The vertical stiffening ribs 9 are provided with two layers, and are respectively provided in the annular support base 4 above and below the upper steel chimney 1 and the lower steel chimney 2, with the plane at the joint as the boundary, and the outer side of the vertical stiffening ribs 9 is welded and fixed to the inner wall of the steel chimney. The vertical stiffening ribs 9 with two layers can better improve the structural strength of the annular support base 4, and the annular support base 4 is firmly fixed to the steel chimney by welding the vertical stiffening ribs 9 to the inner wall of the steel chimney.

[0021] The annular support base 4 is cast by refractory castable 10, so that the annular support base 4 has good fire resistance. A radial and annular steel mesh 11 is arranged inside the refractory castable 10, so that the cast annular support base 4 has good structural stability. The end of the radial and annular steel mesh 11 is welded and fixed to the inner wall of the steel chimney to ensure that the annular support base 4 and the steel chimney can be well fixed together to avoid the downward displacement of the annular support base 4 under the action of gravity.

[0022] During the construction process, taking a 60-80m high-temperature steel chimney as an example, the cylinder wall of the steel chimney will be divided into several sections during the design, each section is about 5m, and the annular stiffening ribs 8 and vertical stiffening ribs 9 of each cylinder wall section are directly welded to the inner cylinder wall of the steel chimney on the ground or in the factory. The steel chimneys of sections 1 and 2 are hoisted and installed first, and the radial annular steel mesh 11 and refractory castables 10 of the annular support base 4 are constructed after the steel chimneys of sections 1 and 2 are installed. Finally, after the annular support base 4 reaches the design strength, the thermal insulation layer 3 of the steel chimneys of sections 1 and 2 are built, and then the steel chimney of section 3 is hoisted, and then the annular support base 4 between sections 2 and 3 is constructed, and then the thermal insulation layer 3 of the steel chimney of section 3 is constructed, and so on.

Claims

1. An elastic support structure for a heat insulation layer in a steel chimney, the steel chimney comprising an upper steel chimney (1) and a lower steel chimney (2) arranged adjacent to each other, characterized in that: The inner walls of the upper steel chimney (1) and the lower steel chimney (2) are both provided with a thermal insulation layer (3), an annular support base (4) is provided between the thermal insulation layer (3) of the upper steel chimney (1) and the lower steel chimney (2), the thermal insulation layer (3) of the upper steel chimney (1) is supported on the top of the annular support base (4), the outer wall of the annular support base (4) is fixedly connected to the inner wall of the steel chimney, a connecting flange (5) is provided on the outer cylinder wall at the joint of the upper steel chimney (1) and the lower steel chimney (2) to connect the two together, an uncompressed refractory fiber felt (6) is provided between the bottom of the annular support base (4) and the top of the thermal insulation layer (3) of the lower steel chimney (2), and a compressed refractory fiber felt (6) is provided between the top of the annular support base (4) and the bottom of the thermal insulation layer (3) of the upper steel chimney (1); The top surface of the annular support base (4) is provided with a single-layer annular stiffening rib (8), the middle portion of which is provided with a double-layer annular stiffening rib (8), and a compressed refractory fiber felt (6) is provided between the middle double-layer annular stiffening rib (8), the center line of the refractory fiber felt (6) is exactly in the same plane as the end surface of the joint of the upper steel chimney (1) and the lower steel chimney (2), and the end of the annular stiffening rib (8) is welded and fixed to the inner wall of the steel chimney; A plurality of vertical stiffening ribs (9) are arranged in a circular manner inside the annular support base (4).

2. The elastic support structure of the thermal insulation layer in a steel chimney according to claim 1, characterized in that: An upward convex ring (7) is provided on the inner side of the top end of the annular support base (4), and the convex ring (7) wraps the lower end of the outer wall of the thermal insulation layer (3) of the upper steel chimney (1). An uncompressed refractory fiber felt (6) is provided between the convex ring (7) and the thermal insulation layer (3).

3. The elastic support structure of the thermal insulation layer in a steel chimney according to claim 2, characterized in that: The thickness of the annular support base (4) is at least 200 mm greater than the thickness of the thermal insulation layer (3); and the height of the convex ring (7) is ≥ 200 mm.

4. The elastic support structure of the thermal insulation layer in a steel chimney according to claim 1, characterized in that: The vertical stiffening ribs (9) are provided in two layers, with the plane at the joint of the upper steel chimney (1) and the lower steel chimney (2) as the boundary, and are respectively arranged in the annular support bases (4) above and below them, and the outer side surfaces of the vertical stiffening ribs (9) are welded and fixed to the inner wall of the steel chimney.

5. The elastic support structure of the thermal insulation layer in a steel chimney according to claim 1, characterized in that: The annular support base (4) is cast by refractory castable (10), a radial and annular steel mesh (11) is arranged inside the refractory castable (10), and the ends of the radial and annular steel mesh (11) are welded and fixed to the inner wall of the steel chimney.

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