A new type of furnace door

Abstract

This utility model relates to a novel furnace door, comprising an outer frame and a stainless steel inner frame welded to the inside of the furnace door. The stainless steel inner frame and the outer frame form an annular cavity structure. V-shaped pins are welded to the flue gas contact surface of the stainless steel inner frame. The annular cavity between the stainless steel inner frame and the outer frame, as well as the flue gas side surface of the stainless steel inner frame, are filled with a layer of ramming material, forming a double-layer isolation structure that wraps the furnace tubes. This can solve the problem of corrosion of the furnace tubes in the upper furnace door area of ​​the waste heat boiler radiant chamber due to long-term contact with flue gas, leading to boiler tube rupture accidents.

Description

Technical Field

[0001] This utility model relates to a novel furnace door and belongs to the field of non-ferrous metallurgical technology. Background Technology

[0002] This invention belongs to the field of non-ferrous metallurgy and is applicable to the upper furnace door of the radiant chamber of a waste heat boiler. The working conditions in the upper furnace door area of ​​the radiant chamber are harsh, characterized by high flue gas temperature, high dust content, rapid wear, and severe low-temperature corrosion, making it the area most prone to tube rupture accidents in waste heat boilers. During boiler manufacturing, the furnace tubes at the furnace door of the radiant chamber are typically bent outwards on a flat heating surface to form a three-dimensional cavity. After the heating surface is installed, a channel is formed connecting the flue gas side to the outside, facilitating cleaning of flue gas and observation of slagging and deformation on the flue gas side heating surface after the boiler is put into operation. After the overall boiler installation is completed, the space between the furnace tubes and the furnace door frame needs to be filled and compacted with ramming material as a protective barrier for the furnace tubes. After the boiler is put into operation, the ramming material will be worn down or cracked and fall off due to the scouring of high-temperature flue gas and frequent changes in flue gas temperature. At this time, the exposed furnace tubes will be in direct contact with flue gas and dust. The flue gas and dust generated by the smelting process often contain strong acids. Due to the need for cleaning and inspection, the furnace door needs to be opened frequently. In addition, during boiler operation, vibration of the heating surface, aging and wear of the furnace door sealing packing, and leakage of cold air will all cause dilute acid (sulfuric acid) to form in the furnace door area, which will react with the exposed furnace tubes (mainly composed of iron) to form low-temperature corrosion. Over time, the furnace tubes will become thinner and their pressure-bearing capacity will be insufficient, leading to tube rupture accidents. To reduce the risk of tube rupture, innovative furnace tube protection methods are needed. Utility Model Content

[0003] In order to solve the above-mentioned problems in the existing technology, this utility model provides a new type of furnace door, which can solve the problem that the furnace tubes in the upper furnace door area of ​​the waste heat boiler radiant chamber are corroded due to long-term contact with smoke and dust, resulting in boiler tube rupture accidents.

[0004] The technical solution of this utility model is as follows:

[0005] A novel furnace door includes an outer frame and a stainless steel inner frame welded to the inside of the furnace door. The stainless steel inner frame and the outer frame form an annular cavity structure. V-shaped pins are welded to the flue gas contact surface of the stainless steel inner frame. The annular cavity between the stainless steel inner frame and the outer frame, as well as the flue gas side surface of the stainless steel inner frame, are filled with a ramming material layer to form a double-layer isolation structure that wraps around the furnace tube.

[0006] The bottom two feet of the V-shaped pin extend into the ramming material layer, and the ends of the feet are provided with hook-shaped anchoring parts that bend to both sides, forming an interlocking structure with the ramming material layer.

[0007] The stainless steel inner frame has a composite anti-deformation structure on the side wall away from the flue gas contact surface. The composite anti-deformation structure includes spaced wavy protrusions, and a dovetail groove is provided between adjacent wavy protrusions. An expansion gap is reserved between the crest of the wavy protrusion and the inner wall of the furnace door outer frame. The wavy protrusions are formed by locally extruding and deforming the base material of the stainless steel inner frame through a stamping process. The dovetail groove is embedded with a ceramic fiber strip that is solidified with the ramming material layer, and a gap is left between the ceramic fiber strip and the bottom of the dovetail groove.

[0008] The wavy protrusion and the dovetail groove are smoothly connected by rounded corners.

[0009] The annular cavity is provided with at least one set of deformable buffer components. The deformable buffer components include metal partitions, which are composed of multiple continuous V-shaped metal plates. The two ends of the metal partitions are welded to the walls of the furnace door outer frame and the stainless steel inner frame, respectively. The interior of the V-shaped metal plates is filled with ceramic fiber boards, and the cross-section of the V-shaped metal plates and the ceramic fiber boards forms a triangle. Elastic connecting rods are provided through the metal partitions and the ceramic fiber boards. The two ends of the elastic connecting rods are connected to the furnace door outer frame and the stainless steel inner frame, respectively, through ball joints. The middle of the elastic connecting rods is provided with a corrugated tube-type telescopic section.

[0010] This utility model has the following beneficial effects:

[0011] This invention utilizes a ring-shaped cavity structure formed by the outer frame of the furnace door and the inner stainless steel frame, combined with a double-layer ramming material layer, to achieve composite wrapping and isolation of the furnace tubes, effectively blocking the penetration of high-temperature flue gas and dispersing thermal stress. The hook-shaped anchoring part of the V-shaped pins and the interlocking structure of the ramming material layer achieve deep anchoring of the refractory material, preventing surface peeling and stress concentration. The composite anti-deformation structure of corrugated protrusions, dovetail grooves, and ceramic fiber strips achieves dynamic absorption of thermal expansion, suppressing frame compression deformation. The synergistic effect of the V-shaped metal plate and the corrugated elastic connecting rod in the deformable buffer assembly achieves absorption of lateral displacement differences and compensation for longitudinal thermal expansion, maintaining the structural integrity and sealing of the furnace door. These structures work together to form a thermal expansion gradient buffer system, ultimately solving the problem of furnace tube corrosion damage and significantly improving anti-knock capability and equipment service life. Attached Figure Description

[0012] Figure 1 This is a cross-sectional view of the overall structure of this utility model;

[0013] Figure 2 This utility model Figure 1 Enlarged view of point A in the middle.

[0014] The reference numerals in the figure are as follows:

[0015] 1. Furnace door outer frame; 2. Stainless steel inner frame; 3. V-shaped pins; 4. Ramming material layer; 5. Furnace tube; 21. Corrugated protrusion; 22. Dovetail groove; 51. Metal partition; 52. Ceramic fiber board; 53. Elastic connecting rod; 54. Corrugated tube type telescopic section. Detailed Implementation

[0016] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0017] Please see Figures 1 to 2 The utility model provides a technical solution:

[0018] The novel furnace door of this embodiment includes an outer frame 1 and a stainless steel inner frame 2 welded to the inside of the furnace door. The stainless steel inner frame 2 and the outer frame 1 form an annular cavity structure. V-shaped pins 3 are welded to the flue gas contact surface of the stainless steel inner frame 2. The annular cavity between the stainless steel inner frame 2 and the outer frame 1, as well as the flue gas side surface of the stainless steel inner frame 2, are filled with a ramming material layer 4, forming a double-layer isolation structure that wraps around the furnace tube 5. Specifically, this solution uses the stainless steel inner frame 2 welded to the inside of the outer frame 1 to form an annular cavity structure, which serves as a core for thermal expansion buffering and heat insulation. In the core area, V-shaped pins 3 are welded to the flue gas contact surface of the stainless steel inner frame 2. The bifurcated structure of the pins enhances the adhesion of the ramming material layer 4. At the same time, ramming material layers 4 are also provided on the flue gas side surface of the annular cavity and the outer frame 1 of the furnace door, which can form a composite wrapping and isolation of the furnace tube 5: the outer ramming material layer 4 resists the direct impact of the furnace flame, and the inner layer is anchored by the V-shaped pins 3 to achieve a flexible combination with the stainless steel inner frame 2. The structure of the double-layer ramming material layer 4 not only blocks the penetration of high-temperature flue gas, but also reduces the interface thermal stress through the gradient matching of the thermal expansion coefficient of the material, which significantly improves the furnace door's anti-knock shock capability.

[0019] As a preferred embodiment, the bottom two feet of the V-shaped pin 3 extend into the interior of the ramming layer 4, and the ends of the feet are provided with hook-shaped anchoring parts that bend to both sides, forming an interlocking structure with the ramming layer 4; the hook-shaped anchoring parts of the V-shaped pin 3 form a barb structure by bending to both sides at the ends, which interlocks with the refractory material during the curing process of the ramming layer 4. When the furnace door is heated, the V-shaped pin 3 restricts the axial displacement of the ramming layer 4 through the hook structure, and its two-foot extension design disperses the thermal stress to the depth of the ramming layer, preventing surface peeling;

[0020] The stainless steel inner frame 2 has a composite anti-deformation structure on the side wall away from the flue gas contact surface. The composite anti-deformation structure includes wavy protrusions 21 distributed at intervals. Dovetail grooves 22 are also provided between adjacent wavy protrusions 21. An expansion gap is reserved between the crest of the wavy protrusions 21 and the inner wall of the outer frame 1 of the furnace door. The wavy protrusions 21 are formed by locally extruding and deforming the base material of the stainless steel inner frame 2 through a stamping process. The dovetail grooves 22 are embedded with ceramic fiber strips that are fixed to the ramming material layer 4. A gap is left between the ceramic fiber strips and the bottom of the dovetail grooves 22. The wavy protrusions 21 and the dovetail grooves 22 are smoothly connected by rounded corners.

[0021] On the non-heated side of the stainless steel inner frame 2, wave-shaped protrusions 21 and dovetail grooves 22 are stamped and alternately arranged. The wave-shaped protrusions 21 have a dynamic expansion gap reserved between the crest and the outer frame 1 of the furnace door. When heated, the crest extends towards the gap, which prevents the stainless steel inner frame 2 from expanding as a whole and squeezing the outer frame 1 of the furnace door. The dovetail groove 22 is embedded with ceramic fiber strips. At the same time, there is a gap between the ceramic fiber strips and the bottom of the dovetail groove 22, which allows the lateral expansion to be absorbed by the dovetail groove 22.

[0022] At least one set of deformable buffer components is provided in the annular cavity. The deformable buffer components include a metal partition 51, which is composed of multiple continuous V-shaped metal plates. The two ends of the metal partition 51 are welded to the walls of the furnace door outer frame 1 and the stainless steel inner frame 2, respectively. The interior of the V-shaped metal plates is filled with ceramic fiber plates 52. The cross-section of the V-shaped metal plates and the ceramic fiber plates 52 forms a triangle. The surface of the ceramic fiber plates 52 is provided with honeycomb-shaped through holes. An elastic connecting rod 53 is provided through the metal partition 51 and the ceramic fiber plates 52. The two ends of the elastic connecting rod 53 are connected to the furnace door outer frame 1 and the stainless steel inner frame 2, respectively, through ball joints. A corrugated tube-type telescopic section 54 is provided in the middle of the elastic connecting rod 53.

[0023] The deformable buffer assembly is horizontally welded between the outer frame 1 and the stainless steel inner frame 2 of the furnace door through a continuous V-shaped metal plate of the metal partition 51. Utilizing the expandable / contractable characteristics of the V-shaped metal plate, it absorbs the lateral displacement difference between the outer frame 1 and the stainless steel inner frame 2 caused by the temperature difference. At the same time, the honeycomb-perforated ceramic fiber board 52 filled inside further buffers high-frequency vibrations through the deformation of the pores. The elastic connecting rod 53 that runs through the assembly achieves multi-degree-of-freedom adjustment through ball joints at both ends, while the corrugated tube-type telescopic section 54 in the middle dynamically compensates for the longitudinal thermal expansion, which not only prevents the ramming material layer 4 from cracking but also maintains the overall sealing of the furnace door.

[0024] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A new type of oven door comprising an oven door outer frame (1), characterized in that: It also includes a stainless steel inner frame (2) welded to the inside of the furnace door, the stainless steel inner frame (2) and the furnace door outer frame (1) forming an annular cavity structure; the flue gas contact surface of the stainless steel inner frame (2) is welded with V-shaped pins (3); the annular cavity between the stainless steel inner frame (2) and the furnace door outer frame (1) and the flue gas side surface of the stainless steel inner frame (2) are filled with ramming material layer (4) to form a double-layer isolation structure that wraps the furnace tube (5).

2. A novel furnace door as claimed in claim 1, wherein: The bottom two feet of the V-shaped pin (3) extend into the interior of the ramming material layer (4), and the ends of the feet are provided with hook-shaped anchoring parts that bend to both sides, and the hook-shaped anchoring parts form an interlocking structure with the ramming material layer (4).

3. A novel furnace door as claimed in claim 2, wherein: The stainless steel inner frame (2) has a composite anti-deformation structure on the side wall away from the flue gas contact surface. The composite anti-deformation structure includes wavy protrusions (21) distributed at intervals. A dovetail groove (22) is also provided between adjacent wavy protrusions (21). An expansion gap is reserved between the crest of the wavy protrusion (21) and the inner wall of the furnace door outer frame (1). The wavy protrusion (21) is formed by locally extruding and deforming the base material of the stainless steel inner frame (2) through a stamping process. The dovetail groove (22) is embedded with a ceramic fiber strip that is fixed with the ramming material layer (4). A gap is left between the ceramic fiber strip and the bottom of the dovetail groove (22).

4. A novel furnace door as claimed in claim 3, wherein: The wavy protrusion (21) and the dovetail groove (22) are smoothly connected by rounded corners.

5. A novel furnace door as claimed in claim 4, characterized in that: At least one set of deformable buffer components is provided in the annular cavity. The deformable buffer components include a metal partition (51), which is composed of multiple continuous V-shaped metal plates. The two ends of the metal partition (51) are respectively welded to the walls of the furnace door outer frame (1) and the stainless steel inner frame (2). The interior of the V-shaped metal plate is filled with ceramic fiber board (52). The cross-section of the V-shaped metal plate and the ceramic fiber board (52) forms a triangle. An elastic connecting rod (53) is provided through the metal partition (51) and the ceramic fiber board (52). The two ends of the elastic connecting rod (53) are respectively connected to the furnace door outer frame (1) and the stainless steel inner frame (2) through ball joints. A corrugated tube telescopic section (54) is provided in the middle of the elastic connecting rod (53).

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