Distributed air inlet device for tubular furnace

Abstract

The utility model relates to the field of gas inlet devices of tube furnaces, in particular to a distributed gas inlet device for a tube furnace. Comprising a furnace tube system, the furnace tube system comprises a furnace tube body, flanges are fixedly connected to the two ends of the furnace tube body, a heat insulation furnace plug is arranged in the furnace tube body, a distributed air inlet device is arranged in the heat insulation furnace plug, the distributed air inlet device comprises an air inlet pipe, and the air inlet pipe is installed in the heat insulation furnace plug. A flow guide base disc is installed at the end, close to the furnace tube body, of the air inlet pipe, a distributed air inlet disc is installed on the arc face of the flow guide base disc, a transmission shaft is installed in the distributed air inlet disc, a plurality of flow guide rotary pieces are installed on the arc face of the transmission shaft, and a connecting ring is installed on the arc face of the transmission shaft. The distributed air inlet device for the tubular furnace has the advantages that the uniformity and the stability of air inlet of the tubular furnace are improved, and the process effect and the product quality are improved.

Description

Technical Field

[0001] This utility model relates to the field of air intake devices for tubular furnaces, and more particularly to a distributed air intake device for tubular furnaces. Background Technology

[0002] In processes such as material synthesis and sintering, chemical vapor deposition, and semiconductor annealing, tube furnaces are commonly used equipment, and their gas inlet method has a significant impact on the process results. Existing tube furnaces have simple gas inlet methods, employing single-point or straight-tube inlet structures, resulting in uneven gas distribution and a large radial velocity gradient. This leads to varying degrees of material contact at different locations, resulting in uneven material reactions. Furthermore, concentrated airflow easily agitates powdery materials, causing them to adhere to the inner wall of the furnace tube, leading to shortened furnace tube life and material loss.

[0003] To address the above problems, this utility model provides a distributed air intake device that improves the uniformity and stability of air intake in tubular furnaces, thereby enhancing process efficiency and product quality. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing technologies.

[0005] To solve the above-mentioned technical problems, this utility model provides a distributed air intake device for a tubular furnace, comprising: a furnace tube system, the furnace tube system including a furnace tube body, flanges fixedly connected to both ends of the furnace tube body, a heat-insulating furnace plug disposed inside the furnace tube body, a distributed air intake device disposed inside the heat-insulating furnace plug, the distributed air intake device including an air intake pipe installed inside the heat-insulating furnace plug, a flow guide base plate installed at the end of the air intake pipe near the furnace tube body, a distributed air intake disc installed on the arc surface of the flow guide base plate, a drive shaft installed inside the distributed air intake disc, a plurality of flow guide vanes installed on the arc surface of the drive shaft, a connecting ring installed on the arc surface of the drive shaft, a plurality of connecting rods fixedly connected to the arc surface of the connecting ring, the connecting rods being fixedly connected to the distributed air intake disc, an air intake channel being opened inside the flow guide base plate, a diversion cover plate being installed at the end of the distributed air intake disc away from the air intake pipe, and a plurality of secondary diversion holes being opened on the inner wall of the diversion cover plate.

[0006] The effects achieved by the above components are as follows: the channel shape of the main flow channel can be radial, spiral, spider web, etc., and the secondary flow guide hole can be cylindrical, trapezoidal, spiral, etc. The shape of the flow guide channel and the shape of the secondary flow guide hole in different main flow channels can be selected according to the specific application scenario and process requirements to achieve the best gas distribution effect.

[0007] Preferably, the air inlet side surface of the guide base plate (23) is provided with N radial main flow grooves, N≥24 and satisfying N=360° / θ, where θ is the central angle of adjacent guide grooves and satisfies 5°≤θ≤30°. The air inlet side surface of the guide base plate is provided with guide vanes. The vane group consists of at least 6 arc-shaped blades evenly distributed along the circumference. The rotation axis of each blade is parallel to the central axis of the guide base plate (23). The tilt angle of the blades is designed to be 5°-30°. The air inlet side surface of the guide base plate (23) is provided with N radial main flow grooves, N≥24 and satisfying N=360° / θ, where θ is the central angle of adjacent guide grooves and satisfies 5°≤θ≤30°.

[0008] The aforementioned components achieve the following effects: the blades are spiral or arc-shaped, used to adjust the airflow diffusion path and break up airflow clusters. The guide vanes adjust the airflow direction by passive rotation (driven by airflow) or active rotation (driven by a motor), the specific choice depending on the actual application scenario and process requirements. This design ensures that after the gas enters the guide base, it can be evenly distributed along each main flow channel, thereby optimizing the airflow diffusion path, reducing the radial velocity gradient, and improving the uniformity of gas distribution.

[0009] Preferably, the guide plate (23) and the diversion cover are made of alumina-silicon carbide composite ceramic, the mass ratio of alumina to silicon carbide is 1.2:0.5, the bending strength is ≥480MPa, and the coefficient of thermal expansion is ≤5.0×10⁻⁶. -6 ℃ -1 .

[0010] Preferably, the synthesis of doped titanium oxide is conducted using a distributed tubular furnace gas inlet device. The ratio of the radius of curvature to the diameter of the guide plate is 0.5:1. After the gas enters the distributed gas inlet plate through the inlet pipe, it is evenly distributed and discharged through several secondary guide holes on the surface of the diversion cover. The gas enters the furnace tube at a uniform speed and flow rate, and the gas velocity distribution is uniform (standard deviation σ = 0.15 m / s). The material adhesion rate on the inner wall of the furnace tube is reduced to 0.3%.

[0011] Preferably, in the 1200℃ tin oxide powder sintering process, the experimental results show that: velocity uniformity: the standard deviation of the radial flow velocity at each point was σ = 0.23 m / s, measured by a hot-wire anemometer; material loss: the powder adhesion rate was 0.7%, measured by weighing method.

[0012] Preferably, in the 1200℃ tin oxide powder sintering process, the following tests were conducted: velocity uniformity: the standard deviation of the radial flow velocity at each point was measured using a hot-wire anemometer, σ = 1.85 m / s; material loss: the powder adhesion rate was measured to be 12.3% by weighing method; compared with Example 2, Example 3 shows a significant problem of uneven airflow distribution in the ordinary straight pipe air inlet.

[0013] Preferably, after the gas is evenly discharged through several secondary guide holes of the diversion cover plate, the gas has a good diversion effect and the airflow can be evenly distributed along each main flow channel, reducing the radial velocity gradient and improving the uniformity of gas distribution. After using the distributed tubular furnace gas inlet device of this utility model, the differences in composition and performance of different parts of the sintered target material can be significantly reduced, and the product quality stability can be greatly improved. The density uniformity of the target material after testing is improved by 30%, and the hardness deviation is reduced by 20%, effectively improving the product qualification rate and production efficiency.

[0014] Compared with related technologies, the distributed air intake device for a tubular furnace provided by this utility model has the following advantages:

[0015] This invention provides a distributed air intake device for a tubular furnace. Through an integrated structure, the shape of the guiding channels in the main flow channels can be radial, spiral, spiderweb-like, etc., while the secondary guiding holes can be cylindrical, trapezoidal, spiral, etc. The shapes of the guiding channels in the main flow channels and the secondary guiding holes can be selected according to specific application scenarios and process requirements to achieve optimal gas distribution. The blades are spiral or arc-shaped, used to adjust the airflow diffusion path and break up airflow clusters. The guiding vanes adjust the airflow direction through passive rotation (driven by airflow) or active rotation (driven by a motor), the specific choice depending on the actual application scenario and process requirements. This design ensures that after entering the guiding base plate, the gas can be evenly distributed along each main flow channel, thereby optimizing the airflow diffusion path, reducing the radial velocity gradient, and improving the uniformity of gas distribution. Attached Figure Description

[0016] Figure 1 A schematic diagram of a distributed air intake device for a tubular furnace provided by this utility model;

[0017] Figure 2 for Figure 1 The diagram shows the internal structure.

[0018] Figure 3 for Figure 2 The diagram shows a partial structural representation.

[0019] Figure 4 for Figure 3 The enlarged view of point A shown.

[0020] The following are the labels in the diagram: 1. Furnace tube system; 11. Furnace tube body; 12. Flange; 13. Insulated furnace plug; 2. Distributed air intake device; 21. Air intake pipe; 22. Distributed air intake disc; 23. Guide base plate; 24. Air intake channel; 25. Guide vane; 26. Diverter cover plate; 27. Secondary diverter hole; 3. Connecting ring; 4. Connecting rod; 5. Drive shaft. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0022] The specific implementation of this utility model will be described in detail below with reference to specific embodiments.

[0023] Please see Figures 1 to 4This utility model provides a distributed air intake device for a tubular furnace, comprising: a furnace tube system 1, the furnace tube system 1 including a furnace tube body 11, flanges 12 fixedly connected to both ends of the furnace tube body 11, a heat-insulating furnace plug 13 disposed inside the furnace tube body 11, a distributed air intake device 2 disposed inside the heat-insulating furnace plug 13, the distributed air intake device 2 including an air intake pipe 21, the air intake pipe 21 being installed inside the heat-insulating furnace plug 13, a flow guide base plate 23 being installed at one end of the air intake pipe 21 near the furnace tube body 11, the flow guide base plate 23 being circular A distributed air intake disc 22 is installed on the arc surface. A drive shaft 5 is installed inside the distributed air intake disc 22. Several guide vanes 25 are installed on the arc surface of the drive shaft 5. A connecting ring 3 is installed on the arc surface of the drive shaft 5. Several connecting rods 4 are fixedly connected to the arc surface of the connecting ring 3. The connecting rods 4 are fixedly connected to the distributed air intake disc 22. An air intake channel 24 is opened inside the guide base disc 23. A diversion cover plate 26 is installed at the end of the distributed air intake disc 22 away from the air intake pipe 21. Several secondary diversion holes 27 are opened on the inner wall of the diversion cover plate 26. The main flow channel shape can be radial, spiral, spider web, etc., and the secondary flow guide hole can be cylindrical, trapezoidal, spiral, etc. The shapes of the flow guide channels and secondary flow guide holes in different main flow channels can be selected according to specific application scenarios and process requirements to achieve the best gas distribution effect. The inlet side surface of the flow guide base plate 23 is provided with N radial main flow channels, N≥24 and satisfying N=360° / θ, where θ is the central angle between adjacent flow guide channels and satisfies 5°≤θ≤30°. The inlet side surface of the flow guide base plate 23 is provided with flow guide vanes 25. The vane group consists of at least 6 arc-shaped blades evenly distributed along the circumference. The rotation axis of each blade is parallel to the central axis of the flow guide base plate 23, and the tilt angle of the blades is designed to be 5°-30°. The inlet side surface of the flow guide base plate 23 is provided with N radial main flow channels. N ≥ 24 and satisfies N = 360° / θ, where θ is the central angle between adjacent guide slots and satisfies 5° ≤ θ ≤ 30°. The blades are spiral or arc-shaped, used to adjust the airflow diffusion path and break up airflow clusters. The guide vanes 25 adjust the airflow direction by passive rotation (driven by airflow) or active rotation (driven by a motor), the specific choice depending on the actual application scenario and process requirements. This design ensures that after the gas enters the guide base 23, it can be evenly distributed along each main flow slot, thereby optimizing the airflow diffusion path, reducing the radial velocity gradient, and improving the uniformity of gas distribution. The guide base 23 and the diversion cover 26 are made of alumina-silicon carbide composite ceramic, with a mass ratio of alumina to silicon carbide of 1.2:0.5, a bending strength ≥ 480 MPa, and a coefficient of thermal expansion ≤ 5.0 × 10⁻⁶. -6 ℃ -1In the synthesis of doped titanium oxide, a distributed tubular furnace gas inlet device was used for the experiment. The ratio of the radius of curvature to the diameter of the guide plate 23 was 0.5:1. After the gas entered the distributed gas inlet plate 22 through the gas inlet pipe 21, it was evenly distributed and discharged through several secondary guide holes on the surface of the diversion cover plate 26. The gas entered the furnace tube with a uniform velocity and flow rate, and the gas velocity distribution was uniform (standard deviation σ = 0.15 m / s). The material adhesion rate on the inner wall of the furnace tube decreased to 0.3%. In the sintering process of tin oxide powder at 1200℃, the experimental results showed: velocity uniformity: the standard deviation of the radial velocity at each point was σ = 0.23 m / s, measured by a hot-wire anemometer; material loss: the powder adhesion rate was 0.7%, measured by weighing method. In the sintering process of tin oxide powder at 1200℃, the velocity uniformity was tested: the standard deviation of the radial velocity at each point was σ = 0.23 m / s, measured by a hot-wire anemometer. The standard deviation of the flow velocity σ = 1.85 m / s; material loss: the powder adhesion rate measured by weighing method is 12.3%; compared with Example 2, Example 3 shows that the uneven airflow distribution of ordinary straight pipe air inlet is significant. After the gas is evenly discharged through several secondary guide holes of the diversion cover plate 26, the diversion effect is good and the airflow can be evenly distributed along each main flow channel. Reducing the radial velocity gradient can improve the uniformity of gas distribution. After using the distributed tubular furnace air inlet device of this utility model, the differences in composition and performance of different parts of the sintered target material can be significantly reduced and the product quality stability can be greatly improved. After testing, the density uniformity of the target material increased by 30% and the hardness deviation decreased by 20%, which effectively improved the product qualification rate and production efficiency.

[0024] The working principle of the distributed air intake device for a tubular furnace provided by this utility model is as follows: The shape of the guiding channel in the main flow channel can be radial, spiral, spider web, etc., and the secondary guiding hole can be cylindrical, trapezoidal, spiral, etc. The shapes of the guiding channels in different main flow channels and the secondary guiding holes can be selected according to the specific application scenario and process requirements to achieve the best gas distribution effect. The blade shape is spiral or arc-shaped, used to adjust the airflow diffusion path and break up airflow clusters. The guiding vane 25 adjusts the airflow direction by passive rotation (driven by airflow) or active rotation (driven by motor). The specific selection is determined according to the actual application scenario and process requirements. This design can ensure that after the gas enters the guiding base plate 23, it can be evenly distributed along each main flow channel, thereby optimizing the airflow diffusion path, reducing the radial velocity gradient, and improving the uniformity of gas distribution.

[0025] The circuits and controls involved in this utility model are all existing technologies, and will not be described in detail here.

[0026] 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 distributed air intake device for a tubular furnace, characterized in that, include: The furnace tube system (1) includes a furnace tube body (11), both ends of which are fixedly connected to flanges (12). A heat-insulating furnace plug (13) is provided inside the furnace tube body (11), and a distributed air intake device (2) is provided inside the heat-insulating furnace plug (13). The distributed air intake device (2) includes an air intake pipe (21), which is installed inside the heat-insulating furnace plug (13). A flow guide plate (23) is installed at one end of the air intake pipe (21) near the furnace tube body (11), and a distributed air intake plate (22) is installed on the arc surface of the flow guide plate (23). The distributed air intake disk (22) is equipped with a drive shaft (5). Several guide vanes (25) are installed on the arc surface of the drive shaft (5). A connecting ring (3) is installed on the arc surface of the drive shaft (5). Several connecting rods (4) are fixedly connected to the arc surface of the connecting ring (3). The connecting rods (4) are fixedly connected to the distributed air intake disk (22). An air intake channel (24) is opened inside the guide base disk (23). A diversion cover plate (26) is installed at the end of the distributed air intake disk (22) away from the air intake pipe (21). Several secondary diversion holes (27) are opened on the inner wall of the diversion cover plate (26).

2. A distributed air intake device for a tubular furnace according to claim 1, characterized in that, The air intake side surface of the guide base plate (23) is provided with N radial main flow grooves, N≥24 and satisfy N=360° / θ, where θ is the central angle of adjacent guide grooves and satisfies 5°≤θ≤30°. The air intake side surface of the guide base plate (23) is provided with guide vanes (25), and the vane group consists of at least 6 arc-shaped blades evenly distributed along the circumference. The rotation axis of each blade is parallel to the central axis of the guide base plate (23), and the tilt angle of the blades is designed to be 5°-30°.

3. A distributed air intake device for a tubular furnace according to claim 1, characterized in that, The guide plate (23) and the diversion cover (26) are made of alumina-silicon carbide composite ceramic, with a mass ratio of alumina to silicon carbide of 1.2:0.5, a bending strength ≥480 MPa, and a coefficient of thermal expansion ≤5.0×10⁻⁶. -6 ℃ -1 .

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