A duct connection structure and a deposition furnace

Abstract

This invention belongs to the field of deposition furnace technology. On one hand, it discloses a duct connection structure, comprising a first sleeve, a second sleeve, and a cap, all fitted over the duct. The first sleeve is fixed to the inner liner and extends from the inner liner into the insulation layer. A first gap is provided between the first sleeve and the duct to allow the duct to slide along the extension direction of the first sleeve and to prevent insulation cotton from entering the inner liner. The second sleeve is fixed to the outer shell and extends from the outer shell to the outside. The duct is fixed to the second sleeve by the cap. A second gap is provided between the second sleeve and the duct, communicating with the insulation layer. Insulation cotton is filled in the second gap and can seal the first gap. On the other hand, this invention discloses a deposition furnace including the duct connection structure described above. While ensuring the sealing between the duct and the inner and outer shells, this invention solves the problem of easy cracking at the connection between the duct and the inner and outer shells due to the large thrust of the duct.

Description

Technical Field

[0001] This invention relates to the field of deposition furnace technology, and more particularly to a duct connection structure and a deposition furnace. Background Technology

[0002] Deposition furnaces typically consist of an inner liner, an insulation layer, an outer shell, and ducts for supplying hot air to the inner liner. Currently, the ducts are welded to the inner liner at one end and to the outer shell in the middle. Because the inner liner generates high temperatures, while the insulation layer of the furnace shell is filled with insulating cotton, the outer shell, which is in contact with the atmosphere, remains close to room temperature. This creates a significant temperature gradient between the duct and the outer shell at their connection point, resulting in substantial internal stress. Furthermore, the high-temperature expansion of the inner liner and duct causes the inner liner to expand towards the insulating layer, resulting in significant thrust on the duct at the connection point with the inner liner and outer shell. This stress concentration at the connection point makes the duct prone to cracking.

[0003] If holes are made in the inner liner to allow the air duct to pass directly into it, although the impact of the inner liner on the air duct can be reduced, it will cause hot air to easily blow away the insulation cotton, contaminate the hot air circulation system, cause fan system failure, and affect the efficiency of electric heating.

[0004] Therefore, it is urgent to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a duct connection structure and a deposition furnace that, while ensuring the airtightness between the duct and the inner liner and outer shell, solves the problem that the connection between the duct and the inner liner and outer shell is prone to cracking due to the large thrust of the duct, and prevents the insulation cotton filled in the insulation layer from being carried into the inner liner by the airflow.

[0006] To achieve this objective, the present invention provides a duct connection structure for connecting a duct and a deposition furnace. The deposition furnace includes an inner liner, an outer shell, and a heat insulation layer disposed between the inner liner and the outer shell. The heat insulation layer is filled with insulating cotton. The duct passes through the heat insulation layer and the outer shell sequentially from the inner liner and extends to the outside, connecting with an external pipe. The duct connection structure includes a first sleeve, a second sleeve, and a cap fitted over the duct, wherein:

[0007] The first sleeve is fixed on the inner liner and extends from the inner liner into the insulation layer. A first gap is provided between the first sleeve and the air duct so that the air duct can slide along the extension direction of the first sleeve and can prevent the insulation cotton from entering the inner liner.

[0008] The second sleeve is fixed to the outer shell and extends outward from the outer shell. The air duct is fixed to the second sleeve by a pipe cap. There is a second gap between the second sleeve and the air duct that connects to the heat insulation layer. The heat insulation cotton is filled in the second gap and can seal the first gap.

[0009] Preferably, the cap can seal the second gap, and a sealing part for sealing the second gap is provided between the cap, the second sleeve and the duct.

[0010] Preferably, the second sleeve is provided with a limiting part, which is configured to limit the insulation cotton to the middle section of the second gap, so that a cavity is formed between the insulation cotton in the second gap and the pipe cap.

[0011] Preferably, the limiting part is an annular plate, which is welded to the inner wall of the middle section of the second sleeve.

[0012] As a preferred option, the cap is provided with a leak detection hole.

[0013] Preferably, the cap is welded to the second sleeve and the air duct respectively to form a first weld and a second weld that are both annular, and the sealing part includes the first weld and the second weld.

[0014] Another aspect of the present invention provides a deposition furnace, the deposition furnace including the duct connection structure described above.

[0015] The beneficial effects of this invention are:

[0016] The duct connection structure and deposition furnace provided by this invention, by setting a first sleeve and a first gap, ensures that the duct is not affected by the inner liner when it expands and deforms due to heat, reducing the thrust on the duct, preventing cracking at the connection between the duct and the inner liner and the outer shell, and preventing the insulation cotton from being carried into the inner liner by the airflow, thereby avoiding fan system failure and affecting the electric heating efficiency of the inner liner; by setting a second sleeve and a second gap, and filling the second gap with insulation cotton to seal the first gap, the temperature gradient at the connection between the duct and the outer shell is reduced, thereby satisfying the sealing between the duct and the inner liner and the outer shell and reducing stress concentration at the connection between the duct and the inner liner and the outer shell. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the duct connection structure provided in an embodiment of the present invention;

[0018] Figure 2 yes Figure 1 A magnified view of the area at point R in the middle.

[0019] In the picture:

[0020] 1. Inner liner; 2. Outer shell; 21. Insulation layer; 22. Thermal insulation cotton; 3. Air duct; 31. First gap; 32. Second gap; 4. First sleeve; 5. Second sleeve; 6. Pipe cap; 61. Leak detection hole; 7. Limiting part. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0022] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0023] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0024] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0025] The main function of the deposition furnace is to continuously form deposited products on the catalyst surface from the gaseous material inside the reaction tube. In this process, the gaseous material inside the tube is usually heated by the hot air outside the tube. The hot air is delivered by the air duct 3 to the inner liner 1, which is at 650 degrees Celsius and 700 degrees Celsius, so as to accelerate the deposition reaction rate of the gaseous material.

[0026] A deposition furnace generally includes an inner liner 1 and an outer shell 2. A heat insulation layer 21 is provided between the inner liner 1 and the outer shell 2, and the heat insulation layer 21 is filled with heat insulation cotton 22 to achieve heat insulation and heat preservation of the inner liner 1. One end of the air duct 3 is welded to the inner liner 1 to fix the air duct 3 and seal the interface between the air duct 3 and the inner liner 1. The air duct 3 can pass through the heat insulation layer 21 and the outer shell 2 in sequence from the inner liner 1 and extend to the outside. The air duct 3 is welded to the outer shell 2 to fix the air duct 3 and seal the interface between the air duct 3 and the outer shell 2, thereby enabling external hot air to be delivered to the inner liner 1 for heating.

[0027] Because the insulation layer 21 is filled with thermal insulation cotton 22, the temperature of the outer shell 2, which is in contact with the atmosphere, is close to room temperature. Since the duct 3 runs from the outer shell 2 to the inner liner 1, a large temperature gradient is formed at the connection between the duct 3 and the outer shell 2, resulting in significant internal stress. Furthermore, the heated inner liner 1 expands towards the insulation layer 21 filled with thermal insulation cotton 22, causing the duct 3 to deform relative to the outer shell 2. Because the duct 3 is welded to both the inner liner 1 and the outer shell 2, the weld seams at the connections between the duct 3 and the inner liner 1 and the outer shell 2 are subjected to significant thrust, leading to cracking of the weld seams at these connections.

[0028] To solve the above problems, such as Figure 1 As shown, this embodiment provides a deposition furnace. The deposition furnace and the air duct 3 are provided with an air duct connection structure. The air duct connection structure includes a first sleeve 4, a second sleeve 5, and a cap 6. The first sleeve 4 is fixed on the inner liner 1 and sleeved on the outside of the air duct 3. The first sleeve 4 extends from the inner liner 1 into the heat insulation layer 21, so that a first gap 31 is formed between the first sleeve 4 and the air duct 3. The first gap 31 allows the air duct 3 to slide along the extension direction of the first sleeve 4 and can prevent the heat insulation cotton 22 in the heat insulation layer 21 from entering the inner liner 1 through the first gap 31. When the inner liner 1 is heated, the inner liner 1 expands toward the heat insulation layer 21 filled with heat insulation cotton 22. The air duct 3 can slide relative to the first sleeve 4 in the first gap 31, thereby avoiding the air duct 3 being directly subjected to the force of the inner liner 1 and reducing the thrust on the air duct 3.

[0029] The second sleeve 5 is welded to the outer shell 2 and fitted over the duct 3, extending outward from the outer shell 2 to form a second gap 32 between the second sleeve 5 and the duct 3. A cap 6 is fitted onto the duct 3 and fixed to the outer shell 2. The duct 3 is fixed to the second sleeve 5 by the cap 6 to secure it. The second gap 32 connects to the insulation layer 21, allowing the insulation cotton 22 to fill the gap and seal the first gap 31. This satisfies the sealing requirements between the duct 3 and the inner liner 1 and the outer shell 2, reduces the temperature gradient at the connection between the duct 3 and the cap 6, and consequently reduces the internal stress at the connection between the duct 3 and the cap 6.

[0030] When the inner liner 1 expands due to heat and compresses the insulation cotton 22 in the insulation layer 21, the insulation cotton 22 can transfer the pressure from the inner liner 1 to the outer shell 2. This causes the second sleeve 5 to generate a torque that compresses the tube wall of the second sleeve 5 towards the center line. As a result, bending stress is generated at the connection between the air duct 3 and the outer shell 2, i.e., at the connection between the cap 6 and the second sleeve 5 and the air duct 3, respectively. Since the second gap 32 is also filled with insulation cotton 22, a portion of the torque on the second sleeve 5 can be transferred to the air duct 3, thereby reducing the bending stress generated at the connection between the air duct 3 and the outer shell 2. This reduces the stress concentration at the connection between the air duct 3 and the outer shell 2, preventing cracking at the connection between the air duct 3 and the outer shell 2. Furthermore, the compressed insulation cotton 22 in the second gap 32 improves the sealing of the first gap 31, thus ensuring the sealing between the air duct 3 and the inner liner 1 and the outer shell 2.

[0031] It is understood that the duct connection structure provided in this embodiment is used to solve the problem that when hot air is delivered to the high-temperature inner liner of the deposition furnace, the large temperature gradient at the connection between the duct 3 and the outer shell 2, and the expansion of the inner liner 1, cause stress concentration at the connection between the duct 3 and the deposition furnace, leading to easy breakage at the connection. Duct connection structures with the same conditions that connect to other furnace bodies are also within the scope of protection of this invention. For example, the furnace body is used to heat the cold medium to be heated delivered to the inner liner 1 by the duct 3, or other furnace bodies where stress concentration occurs at the connection between the duct 3 and the furnace body due to the temperature change of the duct 3 from low temperature to high temperature.

[0032] Furthermore, in order to improve the sealing between the duct 3 and the inner liner 1 and the outer shell 2, the duct cap 6 can close the second gap 32, and a sealing part for sealing the second gap 32 is provided between the duct cap 6, the second sleeve 5 and the duct 3, thereby forming a secondary seal for the first gap 31, which in turn improves the sealing between the duct 3 and the inner liner 1 and the outer shell 2.

[0033] Specifically, in this embodiment, the outer periphery of the cap 6 is welded to the outer shell 2 to form a first annular weld, and the inner periphery of the cap 6 is welded to the outer wall of the duct 3 to form a second annular weld. The first weld, the second weld, and the cap 6 together form a sealing part that seals the second gap 32.

[0034] With the above structure, preferably, in order to reduce the temperature gradient of the duct 3 along its extension direction, a limiting part 7 is provided on the second sleeve 5. The limiting part 7 is configured to limit the insulation cotton 22 to be located in the middle section of the second gap 32, so that the insulation cotton 22 located in the second gap 32 and the pipe cap 6 can form a heat-insulating cavity, thereby increasing the buffer length between the high temperature and low temperature outer shell 2 of the duct 3 and significantly reducing the temperature gradient, thereby reducing the internal stress at the connection between the duct 3 and the outer shell 2.

[0035] Specifically, in this embodiment, the limiting part 7 is an annular plate welded to the inner wall of the middle section of the second sleeve 5 to limit the insulation cotton 22 to be located in the middle section of the second gap 32. It is understood that in other embodiments, the limiting part 7 may also be a positioning element welded to a circumferential array on the inner wall of the middle section of the second sleeve 5, or other structures that can play the same role, which are not limited here.

[0036] Preferably, in order to detect the sealing performance between the duct 3 and the inner liner 1 and the outer shell 2, such as Figure 2 As shown, the pipe cap 6 is provided with a leak detection hole 61. The air duct connection structure can detect the sealing between the air duct 3 and the inner liner 1 and the outer shell 2 by pressurizing the leak detection hole 61.

[0037] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A duct connection structure for connecting a duct (3) and a deposition furnace, the deposition furnace comprising an inner liner (1), an outer shell (2), and a heat insulation layer (21) disposed between the inner liner (1) and the outer shell (2), the heat insulation layer (21) being filled with heat insulation cotton (22), the duct (3) passing sequentially from the inner liner (1) through the heat insulation layer (21) and the outer shell (2) and extending to the outside, the duct (3) being used to deliver external hot air to the inner liner (1) for heating; characterized in that, The duct connection structure includes a first sleeve (4), a second sleeve (5), and a cap (6) fitted outside the duct (3), wherein: The first sleeve (4) is fixed on the inner liner (1) and extends from the inner liner (1) into the heat insulation layer (21). A first gap (31) is provided between the first sleeve (4) and the air duct (3) so that the air duct (3) can slide along the extension direction of the first sleeve (4) and can prevent the heat insulation cotton (22) from entering the inner liner (1). The second sleeve (5) is fixed on the outer shell (2) and extends outward from the outer shell (2). The air duct (3) is fixed to the second sleeve (5) by the pipe cap (6). A second gap (32) is provided between the second sleeve (5) and the air duct (3) to the heat insulation layer (21). The heat insulation cotton (22) is filled in the second gap (32) and can seal the first gap (31). The second sleeve (5) is provided with a limiting part (7), which is configured to limit the insulation cotton (22) in the middle section of the second gap (32) so that a cavity is formed between the insulation cotton (22) in the second gap (32) and the cap (6); When the inner liner (1) is heated, the inner liner (1) expands toward the insulation layer (21) filled with insulation cotton (22), and the air duct (3) slides in the first gap (31) relative to the first sleeve (4) to avoid the air duct (3) being directly subjected to the force of the inner liner (1). The insulation cotton (22) transmits the pressure from the inner liner (1) to the outer shell (2), causing the second sleeve (5) to generate a torque that is squeezed from the wall of the second sleeve (5) toward the center line. The insulation cotton (22) filled in the second gap (32) transmits part of the torque on the second sleeve (5) to the air duct (3), reducing the bending stress generated at the connection between the air duct (3) and the outer shell (2).

2. The duct connection structure according to claim 1, characterized in that, The cap (6) can close the second gap (32), and a sealing part for sealing the second gap (32) is provided between the cap (6), the second sleeve (5) and the air duct (3).

3. The duct connection structure according to claim 1, characterized in that, The limiting part (7) is an annular plate, which is welded to the inner wall of the middle section of the second sleeve (5).

4. The duct connection structure according to claim 1, characterized in that, The cap (6) is provided with a leak detection hole (61).

5. The duct connection structure according to claim 2, characterized in that, The cap (6) is welded to the second sleeve (5) and the air duct (3) respectively to form a first weld and a second weld that are both annular. The sealing part includes the first weld and the second weld.

6. A deposition furnace, characterized in that, Includes the duct connection structure as described in any one of claims 1 to 5.

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