A furnace wall structure for absorbing thermal expansion of an annular furnace

Abstract

A furnace wall structure for absorbing thermal expansion of an annular furnace comprises: an outer column (1), a lower longitudinal beam (2), an upper longitudinal beam (3), a furnace top beam (4), an inner column (5), a side wall small column (6), an outer furnace shell baffle (7), a furnace wall steel plate (8), a locking block (9), a locking bolt (10), a locking nut (11), a locking angle steel (12), an inner furnace shell baffle (13), a V-shaped expansion joint (14), and a furnace wall refractory material (15). The advantages are that the structure is simple and durable, and the problem of deformation of the side wall steel plate of an annular heating furnace or an annular annealing furnace when it expands due to heat is solved. The deformation of the furnace shell structure is well prevented from damaging the overall structure of the furnace wall refractory material, and the friction between the furnace body and the workbench caused by the deformation of the furnace body structure is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of annular heating furnaces and annular annealing furnaces in steel plants, and in particular relates to a side wall structure used for absorbing heat expansion of annular furnaces. Background Art

[0002] The furnace wall structure of the annular heating furnace or annular annealing furnace in a steel plant is usually composed of a casting material layer, a lightweight brick layer, a fiberboard or a calcium silicate board layer, and the outermost layer is a furnace wall steel plate. The anchoring bricks for fixing the casting material are fixed with anchor hooks welded to the furnace wall steel plate. The annular furnace wall steel plate is welded to the annular furnace body column to form an outer ring furnace wall steel plate and an inner ring furnace wall steel plate. Since the expansion of the furnace wall refractory material is considered when the furnace wall refractory material is built, the outermost furnace wall steel plate is welded to the inner and outer ring columns of the annular furnace and cannot absorb thermal expansion, resulting in the furnace body refractory material being able to expand freely, while the furnace wall steel plate cannot expand freely, thereby causing the furnace body refractory material to crack, the furnace wall steel plate to deform, and the column to bend. In order to prevent the side wall steel plate of the annular heating furnace or annular annealing furnace from causing the above-mentioned deformation when it is heated and expanded, its thermal expansion needs to be absorbed. Based on this concept, after many tests in the project, the furnace wall structure of the present invention was developed. Summary of the invention

[0003] The purpose of the present invention is to provide a side wall structure for absorbing heat expansion of an annular furnace, which solves the problem that the side wall steel plate of an annular heating furnace or annular annealing furnace deforms when it expands due to heat. It well prevents the deformation of the furnace shell structure from damaging the overall structure of the furnace wall refractory material, and at the same time avoids the friction between the furnace body and the workbench caused by the deformation of the furnace body structure.

[0004] The present invention mainly includes an outer column 1, a furnace top beam 4, an inner column 5, an outer furnace shell baffle 7, a locking block 9, a locking bolt 10, a locking nut 11, a locking angle steel 12, an inner furnace shell baffle 13, and a V-shaped expansion joint 14.

[0005] The furnace space of the annular furnace is constructed into a "door" structure by the side walls and the furnace roof. The side walls are divided into the outer wall and the inner wall. The side wall structure of the annular furnace is composed of refractory materials, furnace wall steel plates, and furnace body steel structures from the furnace combustion space outward. The invention is applied to the side wall steel plates and the furnace body steel structure. First, the inner and outer walls of the annular furnace are divided into two concentric regular N-gons according to different diameters. According to the direct changes of the annular furnace, different N-gons are generally taken. The corresponding regular polygon internal angle is (N-2)×180° / N. It is necessary to ensure that the external angle of N deformation is ≤15°, and the external angle is usually 5°~12°.

[0006] For example, a circular furnace with a diameter of 50 meters has its outer wall and inner wall divided into 36-sided or 30-sided polygons, with an outer angle of 10° or 12°. The outer column 1 is arranged at the vertex of the N-sided polygon of the outer wall, and the inner column 5 is arranged at the vertex of the N-sided polygon of the inner wall. The outer column 1 and the inner column 5 are collinear with the diameter of the circular furnace. The outer column 1 is connected to the corresponding inner column 5 through the furnace top beam 4, and the bolt connection method is adopted. Every two outer columns 1 are connected to each other as a whole by the lower longitudinal beam 2 and the upper longitudinal beam 3, and the connection method is welding; similarly, the lower longitudinal beam 2 and the upper longitudinal beam 3 are connected to each other between two adjacent inner columns 5. The furnace shell structure includes a total of 2×N independent block furnace wall steel plates 8 according to the divided N-sided polygons, and the outer ring of the circular furnace has N blocks and the inner ring has N blocks. As in the previous example, the diameter of the circular furnace is 50 meters, and the furnace wall steel plates are 72 or 60. A furnace wall steel plate 8 is arranged between every two outer columns 1 or every two inner columns 5. The side wall small columns 6 are arranged on the furnace wall steel plate 8 along the circumferential direction, with a spacing of 1 meter to 1.5 meters, and are welded to the furnace wall steel plate 8 to support the furnace wall steel plate 8 and strengthen the strength of the furnace wall steel plate 8. The upper part of the side wall small columns 6 is fixed to the upper longitudinal beam 3, and the lower part of the side wall small columns 6 is fixed to the lower longitudinal beam 2, all of which adopt a bolt connection structure. For the outer side of the annular furnace, the locking angle steel 12 is arranged at both ends of the furnace wall steel plate 8 close to the outer column 1, and one of its corners is vertical to the furnace wall steel plate 8 and is continuously fully welded. The arrangement of the locking angle steel 12 of the furnace wall steel plate 8 on the inner side of the annular furnace is the same as that on the outer side of the annular furnace.

[0007] The outer furnace shell baffle 7 is arranged on the furnace side of the outer column 1, and the inner furnace shell baffle 13 is arranged on the furnace side of the inner column 5. The outer furnace shell baffle 7 and the outer column 1, and the inner furnace shell baffle 13 and the inner column 5 are welded. After the connection is completed, the outer furnace shell baffle 7 and the inner furnace shell baffle 13 are completely parallel along the diameter direction of the annular furnace and parallel to the furnace wall steel plate 8. The side spacing between the locking angle steel 12 and the outer furnace shell baffle 7 or the inner furnace shell baffle 13 is 25-30mm.

[0008] The locking angle steel 12, the locking block 9, the locking nut 11, and the locking bolt 10 together form a locking structure. One end of the locking block 9 is connected to the locking angle steel 12 by bolts, and the other end is provided with a threaded hole, which is connected with the locking bolt 10 and the locking nut 11. After the locking bolt 10 is screwed in, the furnace wall steel plate 8 is fixed to the outer furnace shell baffle 7 or the inner furnace shell baffle 13, and the locking bolt 10 is fixed with the locking nut 11. The locking structure is arranged at intervals of 300 to 350 mm along the height direction of the annular furnace. After the locking structure is installed, the joints of two adjacent furnace wall steel plates 8 are welded at the position of each outer column 1 or inner column 5 with a V-shaped expansion joint 14. After the furnace shell structure is fixed, the furnace wall refractory material 15 is arranged on the side wall steel plate 8 in a conventional manner near the furnace side.

[0009] The V-shaped expansion joint 14 is made of SUS304, with a width of 70mm and the same height as the furnace wall steel plate 8. It is formed by stamping and bending a V-shaped stainless steel plate as a whole, and the width of both sides of the V-shaped is 20mm. For the inner or outer furnace wall steel plate of the annular furnace, the two sides of the V-shaped expansion joint 14 are respectively welded to the furnace wall steel plate 8 with interval welding, with an interval of 100-150mm and a weld length of 100mm to form the entire annular furnace shell.

[0010] The outer furnace shell baffle 7 and the inner furnace shell baffle 13 of the annular furnace are both in a "V" shape, and are welded to the outer column 1 and the inner column 5. The angle between each and the end face of the column is 6° (the angle varies depending on the number of polygons divided by the annular furnace).

[0011] The advantages of the present invention are: simple structure, durability, can be used in steel mill steel rolling annular heating furnace or annular furnace annealing furnace, V-shaped expansion joint absorbs the thermal expansion of furnace body steel plate along the circumferential direction, so that the furnace shell steel plate and furnace body steel structure are not deformed. When the annular furnace is heated, the side wall steel plate 8 is heated and expanded along the circumferential direction, which is well absorbed by the structure of the invention, and the effect is obvious. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a cross-sectional view of the furnace wall of the annular furnace, wherein the furnace body columns 1, the lower longitudinal beams 2, the upper longitudinal beams 3, the furnace top beams 4, the inner columns 5, and the furnace wall refractory materials 15.

[0013] Figure 2 for Figure 1 AA view in. Among them, the outer furnace shell baffle 7, furnace wall steel plate 8, locking block 9, locking bolt 10, locking nut 11, locking angle steel 12, inner furnace shell baffle 13, V-type expansion joint 14.

[0014] Figure 3 It is the external view of the annular furnace. Among them, the side wall small column 6, the outer furnace shell baffle 7, and the locking block 9.

[0015] Figure 4 This is an enlarged view of the locking device. DETAILED DESCRIPTION

[0016] The annular furnace wall structure of the present invention is specifically implemented as follows in conjunction with the accompanying drawings. The present invention comprises an outer column 1, a lower longitudinal beam 2, an upper longitudinal beam 3, a furnace top beam 4, an inner column 5, a side wall small column 6, an outer furnace shell baffle 7, a furnace wall steel plate 8, a locking block 9, a locking bolt 10, a locking nut 11, a locking angle steel 12, an inner furnace shell baffle 13, a V-shaped expansion joint 14, and a furnace wall refractory material 15.

[0017] The outer column 1 and the inner column 5 are 250-300mm hot-rolled H-shaped steel, the lower longitudinal beam 2 and the upper longitudinal beam 3 are 100-150mm small hot-rolled H-shaped steel, and the furnace top beam 4 is 250-300mm hot-rolled H-shaped steel, all of which are made of carbon steel. The outer column 1 and the inner column 5 are installed on the concrete foundation on both sides of the inner and outer sides of the annular furnace according to the pre-set positions. The outer columns 1 of each furnace body are connected by the lower longitudinal beam 2 and the upper longitudinal beam 3, and the inner column 5 is installed in the same way as the outer column 1. The furnace top beam 4 is connected between the outer furnace body columns 1 and the inner columns 5 along the furnace width direction to form a steel structure frame of the annular furnace body.

[0018] The outer furnace shell baffle 7 is made of 10-12mm thick ordinary carbon steel, 220-250mm wide, and the same height as the furnace wall steel plate 8, in a V shape, with an angle of 180°-(360°÷N), such as 170° or 168° in the previous example.

[0019] The pre-made outer furnace shell baffle 7 is welded to the furnace side of the outer column 1 to ensure that the angle between the outer furnace shell baffle 7 and the two sides of the outer column 1 is 5° or 6° (same as the previous example), and the inner furnace shell baffle 13 is welded to the inner column 5. After the installation is completed, the outer furnace shell baffle 7 and the inner furnace shell baffle 13 are parallel to the diameter direction of the annular furnace and parallel to the furnace wall steel plate 8.

[0020] The small columns 6 of the furnace wall side wall are I10 I-beams, the furnace wall steel plate 8 is a 6-8mm ordinary carbon steel plate, the locking angle steel is ∟65x65x5, made of ordinary carbon steel, and the locking angle steels 12 are welded on both sides of the furnace wall steel plate 8 away from the furnace side, and one side of the locking angle steel 12 is vertically welded to the furnace wall steel plate 8; the locking angle steel 12 is 130-150mm away from the edge of the furnace wall steel plate, and the small columns 6 of the furnace wall side wall are welded on the furnace wall steel plate 8 at intervals of 200-400mm along the circumferential direction of the annular furnace.

[0021] The furnace wall side wall small columns 6, furnace wall steel plates 8, and locking angle steels 12 are pre-processed and welded into independent block structures according to appropriate sizes, ensuring that the joint width of all furnace wall steel plates 8 is 30-60 mm, and the joint is located at the flange center line of the outer column 1 or the inner column 5. The lower part of the furnace wall side wall small columns 6 are supported on the lower longitudinal beam 2 and fixed with oblong hole bolts, and the upper part of the side wall small columns 6 and the upper longitudinal beam 3 are fixed with oblong hole bolts. All furnace wall steel plates 8 are installed according to the above operations and fixed to the annular furnace steel structure frame.

[0022] The material of the V-shaped expansion joint 14 is SUS304, with a width of 70mm, a height the same as the furnace wall steel plate 8, a thickness of 4.5mm, an angle of 55-60°, and is formed by integrally stamping and bending a V-shaped stainless steel plate. The sharp angles of the V-shaped stainless steel plate are rounded, and the width of both sides of the V-shape is 20mm. The welding of the two sides of the V-shaped expansion joint 14 to the furnace wall steel plate 8 is performed by interval welding, with an interval of 100-150mm and a weld of 100mm. The joints between all the annular furnace wall steel plates 8 are connected by the V-shaped expansion joint 14 to form an annular furnace shell as a whole.

[0023] The locking block 9 is 120-130 mm long, 50-60 mm wide, 18-20 mm thick, and made of carbon steel. A φ18 hole is opened at one end, and the locking block 9 is fixed to the locking angle steel 12 with ordinary bolts. An M16 threaded hole is opened at the other end for screwing in the locking bolt 10. The distance between the two holes is 70-80 mm, and one is installed every 200-210 mm along the height direction of the furnace.

[0024] The locking bolt 10 is an M16 common bolt with a length of 120 to 150 mm, and the locking nut 11 is matched with the locking bolt 10 .

[0025] During installation, first connect the locking block 9 and the locking angle steel 12 with bolts, match the locking bolt 10 with the locking nut 11, and screw it into the threaded hole. After the edges of the furnace wall steel plate 8 are all in contact with the outer furnace shell baffle 7, tighten the locking nut 11 to fix the furnace wall steel plate 8. After each of the remaining locking blocks is adjusted and fixed according to the above method, the inner and outer shell structure of the annular furnace is finally formed.

[0026] After the inner and outer furnace shells are installed, the furnace is built with refractory materials 15 in a conventional manner. The annular furnace roof is a conventional hanging furnace roof, and finally the annular furnace hearth space is formed, and the side walls that can absorb heat expansion are installed.

[0027] Finally, it should be noted that: Obviously, the above examples are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from them are still within the scope of protection of the present invention.

Claims

1. A furnace wall structure for absorbing thermal expansion of an annular furnace, wherein the inner and outer walls of the annular furnace are divided into two concentric regular N-gons according to different diameters, and different N-gons are directly changed according to the annular furnace, and the corresponding regular polygon interior angle is (N-2)×180° / N; characterized in that: include: An outer column (1), a lower longitudinal beam (2), an upper longitudinal beam (3), a furnace top beam (4), an inner column (5), a side wall small column (6), an outer furnace shell baffle (7), a furnace wall steel plate (8), a locking block (9), a locking bolt (10), a locking nut (11), a locking angle steel (12), an inner furnace shell baffle (13), a V-shaped expansion joint (14), and a furnace wall refractory material (15); An outer column (1) is arranged at the vertex position of the N-gon of the outer wall, and an inner column (5) is arranged at the vertex position of the N-gon of the inner wall. The outer column (1) and the inner column (5) are collinear with the diameter of the annular furnace. The outer column (1) and the corresponding inner column (5) are connected via a furnace top beam (4) by bolt connection. Every two outer columns (1) are connected to each other as a whole by a lower longitudinal beam (2) and an upper longitudinal beam (3) by welding. Two adjacent inner columns (5) are connected to each other by a lower longitudinal beam (2) and an upper longitudinal beam (3). The furnace shell structure includes a total of 2×N independent block furnace wall steel plates (8) according to the divided N-gon, N outer rings of the annular furnace, and N inner rings. Every two outer columns (1) or every two inner columns (5) are connected to each other by a lower longitudinal beam (2) and an upper longitudinal beam (3). A furnace wall steel plate (8) is arranged between the inner side columns (5), and the side wall small columns (6) are arranged on the furnace wall steel plate (8) along the circumferential direction, with a spacing of 1 meter to 1.5 meters, and are welded to the furnace wall steel plate (8) to support the furnace wall steel plate (8) and strengthen the strength of the furnace wall steel plate (8). The upper part of the side wall small columns (6) is fixed to the upper longitudinal beam (3), and the lower part of the side wall small columns (6) is fixed to the lower longitudinal beam (2), and both are connected by bolts; for the outer side of the annular furnace, the locking angle steel (12) is arranged at the two ends of the furnace wall steel plate (8) close to the outer side columns (1), and one of its corners is in a vertical state with the furnace wall steel plate (8), and is continuously and fully welded. The arrangement of the locking angle steel (12) of the furnace wall steel plate (8) on the inner side of the annular furnace is the same as that on the outer side of the annular furnace; The outer furnace shell baffle (7) is arranged on the side of the outer column (1) close to the furnace chamber, and the inner furnace shell baffle (13) is arranged on the side of the inner column (5) close to the furnace chamber. The outer furnace shell baffle (7) and the outer column (1), and the inner furnace shell baffle (13) and the inner column (5) are all connected by welding. The outer furnace shell baffle (7) and the inner furnace shell baffle (13) are completely parallel along the diameter direction of the annular furnace and parallel to the furnace wall steel plate (8). The side spacing between the locking angle steel (12) and the outer furnace shell baffle (7) or the inner furnace shell baffle (13) is 25 to 30 mm. The locking angle steel (12), the locking block (9), the locking nut (11) and the locking bolt (10) together form a locking structure. One end of the locking block (9) is connected to the locking angle steel (12) by bolts, and the other end is provided with a threaded hole for connecting with the locking bolt (10) and the locking nut (11). After the locking bolt (10) is screwed in, the furnace wall steel plate (8) is fixed to the outer furnace shell baffle (7) or the inner furnace shell baffle (13), and the locking bolt (10) is fixed by the locking nut (11). The locking structure is arranged at intervals of 300 to 350 mm along the height direction of the annular furnace. After the locking structure is installed, the joints of two adjacent furnace wall steel plates (8) are welded at the position of each outer column (1) or inner column (5) by a V-shaped expansion joint (14). After the furnace shell structure is fixed, a furnace wall refractory material (15) is arranged on the furnace wall steel plate (8) near the furnace chamber side.

2. The furnace wall structure for absorbing thermal expansion of an annular furnace according to claim 1, characterized in that: The V-shaped expansion joint (14) is made of SUS304, has a width of 70 mm, and is the same height as the furnace wall steel plate (8). It is formed by integrally stamping and bending a V-shaped stainless steel plate, and the width of both sides of the V-shape is 20 mm. For the inner or outer furnace wall steel plate of the annular furnace, the two sides of the V-shaped expansion joint (14) are respectively welded to the furnace wall steel plate (8) by spacer welding, with a spacing of 100 to 150 mm and a weld length of 100 mm, so as to form the entire annular furnace shell.

3. The furnace wall structure for absorbing thermal expansion of an annular furnace according to claim 1, characterized in that: The outer furnace shell baffle (7) and the inner furnace shell baffle (13) of the annular furnace are both in a "V" shape and are welded to the outer column (1) and the inner column (5), and the angle between each and the end face of the column is 6°.

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