Glue return prevention collecting tank of pressureless sintering silicon carbide vacuum furnace

Abstract

The utility model discloses a non-pressure sintering silicon carbide vacuum furnace glue return prevention collecting tank, the vacuum furnace comprises a furnace body, a muffle box is arranged in the furnace body, the technical scheme is that the non-pressure sintering silicon carbide vacuum furnace glue return prevention collecting tank comprises a dewaxing cap, a dewaxing pipe and a collecting tank, the dewaxing cap, the dewaxing pipe and the collecting tank are sequentially communicated from top to bottom, the dewaxing pipe comprises a dewaxing pipe I, a dewaxing pipe II and a dewaxing pipe III, and the dewaxing pipe I, the dewaxing pipe II and the dewaxing pipe III are communicated in sequence. The dewaxing pipe II is fixed on the inner wall of the bottom of the furnace body, the dewaxing pipe I is in butt joint with the dewaxing pipe II from top to bottom in the muffle box, the dewaxing pipe III is fixed on the outer wall of the bottom of the furnace body and is aligned with the center of the dewaxing pipe II, the dewaxing pipe III is provided with a cooling water jacket, the cooling water jacket is welded with a flow blocking disc, the flow blocking disc is communicated with the cooling water jacket, and the flow blocking disc is filled with cooling water. And the collecting tank is sequentially connected with the condensing tank, the roots pump and the mechanical pump through pipelines, so that the evacuation rate during vacuum rubber discharging is not influenced, and graphite parts and carbon felts of the heating chamber are greatly protected from being oxidized.

Description

Technical Field

[0001] This utility model belongs to the technical field, specifically relating to a non-pressure sintering silicon carbide vacuum furnace anti-backflow collection tank. Background Technology

[0002] Silicon carbide sintering is divided into reaction sintering, pressureless sintering, and recrystallization sintering. Pressureless sintering mostly uses a debinding and sintering integrated furnace. In the whole process, debinding and sintering are completed in a vacuum sintering furnace. Before the temperature reaches 900 degrees, a vacuum state is maintained. In order to form the green body, glue and other components are added. These components will volatilize and be eliminated as the temperature changes. After the temperature reaches 900 degrees, it enters the reaction sintering state.

[0003] Currently, conventional high-temperature vacuum sintering furnaces are equipped with a dedicated degumming system. The connection between the degumming system and the high-temperature vacuum furnace is a straight pipe. During the degumming stage before 900 degrees Celsius, the temperature at this location is relatively low, and the volatilized glue, water vapor, etc., will condense here. As the furnace temperature continues to rise, when the furnace temperature reaches 2300 degrees Celsius, the temperature radiation reaching this location will be around 300 degrees Celsius. The remaining moisture, glue, and other volatile substances will turn into gaseous substances and enter the furnace body, corroding high-temperature components such as graphite. Over time, the insulation layer (mostly graphite felt) will lose its insulation effect due to increased oxidation, and the graphite and other heating components will break due to oxidation, greatly increasing the maintenance cycle and cost. Utility Model Content

[0004] In order to overcome the above-mentioned technical problems in the existing technical field, the purpose of this utility model is to provide a pressureless sintering silicon carbide vacuum furnace anti-backflow collection tank, which does not affect the air extraction state during the glue discharge stage, and can effectively prevent the corrosion problem caused by the volatilization of water vapor and glue gas into the furnace body due to high temperature radiation.

[0005] This utility model provides a pressureless sintering silicon carbide vacuum furnace anti-rebound collection tank. The vacuum furnace includes a furnace body, and a muffle box is provided inside the furnace body. The technical solution of this utility model includes a dewaxing cap, a dewaxing tube collection tank, and the dewaxing cap, dewaxing tube, and collection tank are connected sequentially from top to bottom. The dewaxing tube includes dewaxing tube I, dewaxing tube II, and dewaxing tube III. Dewaxing tube II is fixed to the inner wall of the bottom of the furnace body. Dewaxing tube I is connected to dewaxing tube II from the inside of the muffle box from top to bottom. Dewaxing tube III is fixed to the outer wall of the bottom of the furnace body and aligned with the center of dewaxing tube II. Dewaxing tube III is provided with a cooling water jacket, and a baffle plate is welded to the cooling water jacket. The baffle plate is connected to the cooling water jacket and is filled with cooling water. The collection tank is connected to a condenser, a Roots pump, and a mechanical pump in sequence through pipes.

[0006] The dewaxing tube III is made of metal and is connected to the furnace body via a flange, with a vacuum seal in the middle via a sealing ring.

[0007] The flow deflector is provided in several units, which are inclined downwards at 45 degrees and arranged alternately.

[0008] The dewaxing cap is screwed onto the dewaxing tube I by threads, and the dewaxing cap has an inverted conical tube inside.

[0009] The collection tank is connected to the bottom of the dewaxing pipe III via a flange. The collection tank is tilted at 45 degrees and a baffle is installed inside the collection tank.

[0010] The anti-backflow collection tank for the pressureless sintering silicon carbide vacuum furnace provided by this utility model has the following advantages: it does not affect the evacuation rate during vacuum debinding, and it greatly protects the graphite components, carbon felt and other materials in the heating chamber that are not resistant to oxidation, thus extending the service life of the heating element and insulation material. It also protects the downstream mechanical pump group and greatly reduces maintenance costs. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the present utility model;

[0012] The image is labeled as follows:

[0013] 1. Furnace body; 2. Muffle box; 3. Dewaxing cap; 4. Inverted conical tube; 5. Dewaxing tube I; 6. Dewaxing tube II; 7. Cooling water outlet; 8. Dewaxing tube III; 9. Collection tank; 10. Condensate tank; 11. Roots pump; 12. Mechanical pump; 13. Baffle B; 14. Baffle A; 15. Cooling water inlet; 16. Baffle plate. Detailed Implementation

[0014] The following detailed description of the anti-backflow collection tank for pressureless sintering silicon carbide vacuum furnace provided by this utility model, with reference to the accompanying drawings and an embodiment, will be provided in detail.

[0015] Example

[0016] Reference Figure 1This embodiment describes a pressureless sintering silicon carbide vacuum furnace anti-return collection tank, applied to a vacuum furnace. The vacuum furnace includes a furnace body 1, and a muffle box 2 is provided inside the furnace body 1. The present invention includes a dewaxing cap 3, a dewaxing tube, and a collection tank 9. The dewaxing cap 3, the dewaxing tube, and the collection tank 9 are connected sequentially from top to bottom. The dewaxing tube includes a dewaxing tube I5, a dewaxing tube II6, and a dewaxing tube III8. The dewaxing tube II6 is fixed to the inner wall of the bottom of the furnace body 1. The dewaxing tube I5 is connected from the inside of the muffle box 2 to the dewaxing tube II6 from top to bottom. The dewaxing tube III8 is fixed to the outer wall of the bottom of the furnace body 1 and aligned with the center of the dewaxing tube II6. The dewaxing tube III8 is provided with a cooling water jacket, and a baffle plate 16 is welded to the cooling water jacket. The baffle plate 16 is connected to the cooling water jacket and is filled with cooling water. The collection tank 9 is connected sequentially to a condenser 10, a Roots pump 11, and a mechanical pump 12 through pipes.

[0017] The dewaxing tube III8 is made of metal and is connected to the furnace body 1 via a flange, with a vacuum seal in the middle via a sealing ring.

[0018] The baffle plate 16 is provided in several parts, and the baffle plate 16 is inclined downward at 45 degrees to the outer wall of the cooling water jacket and is arranged alternately.

[0019] The cooling water jacket is provided with a cooling water inlet 15 and a cooling water outlet 7 on its outer side.

[0020] Furthermore, the cooling water inlet 15 is located on the lower part of the outer side of the cooling water jacket, and the cooling water outlet 7 is located on the upper part of the outer side of the cooling water jacket.

[0021] The dewaxing cap 3 is screwed onto the dewaxing tube I by threads, and the dewaxing cap 3 has an inverted conical tube 4 inside.

[0022] The collection tank 9 is connected to the dewaxing pipe III8 via a flange. The collection tank 9 is tilted to one side at a 45-degree angle to the horizontal. Two baffles are installed inside the collection tank: one baffle A14 is installed on the upper inner wall of the collection tank, and the other baffle B13 is installed on the lower inner wall of the collection tank. The baffle A14 installed on the upper inner wall of the collection tank is also tilted to the opposite side of the tilting direction of the collection tank at a 45-degree angle to the horizontal. The baffle B13 fixed on the lower inner wall of the collection tank is arranged parallel to the baffle A14.

[0023] Furthermore, the length of the baffle A14 is not shorter than that of the guide plate B13.

[0024] When installing and using the anti-backflow collection tank for the pressureless sintering silicon carbide vacuum furnace, first fix the dewaxing tube II6 to the furnace body 1. When fixing, ensure that the centers of the dewaxing tube II6 and the dewaxing tube III8 are aligned. Then, connect the dewaxing tube I5 from the inside of the muffle box to the dewaxing tube II6 from top to bottom. Then, screw the dewaxing cap 3 onto the dewaxing tube I5. The dewaxing cap 3 has an inverted conical tube 4 inside, which does not affect the efficiency of vacuuming and can prevent the probability of glue gas entering the furnace body from bottom to top at high temperatures.

[0025] The dewaxing tube III8 is equipped with a cooling water jacket and an internally welded 45-degree baffle plate 16. The glue gas can pass smoothly from top to bottom, but at high temperatures, the glue gas, water vapor, etc., which radiate heat from top to bottom, are blocked by the baffle plate 16 when they enter the furnace body from bottom to top. The baffle plate contains cooling water, which is at a lower temperature, so the gas is cooled and then returns to the collection tank. Even if a small amount of gas enters the furnace body, it will pass through the inverted cone structure inside the dewaxing cap, which will only cause oxidation of the inverted cone structure, thus protecting other graphite components in the heating chamber. The dewaxing tube is a metal component, which further ensures the heat conduction efficiency and cooling effect.

[0026] The collecting tank 9 is connected to the dewaxing pipe III8 by a flange at a 45-degree angle, and an internal baffle plate is also installed at a 45-degree angle. During the lower temperature discharge stage, after the glue and moisture are extracted, they quickly enter the downward-sloping front half of the collecting tank, leaving only a very small amount of glue at the rear. This further reduces the amount of glue gas and water vapor entering the furnace body due to heat radiation at high temperatures. The collecting tank is connected to the condenser, Roots pump, and mechanical pump via pipes. The main function of the condenser is to condense the extracted glue and other gases here, preventing them from entering the Roots pump and mechanical pump, thus better protecting the pump body.

Claims

1. A pressureless silicon carbide sintering vacuum furnace anti-backflow collection tank, the vacuum furnace comprising a furnace body, the furnace body being equipped with a muffle box, characterized in that: The system includes a dewaxing cap, a dewaxing tube collection tank, and the dewaxing cap, dewaxing tube, and collection tank connected sequentially from top to bottom. The dewaxing tube includes dewaxing tube I, dewaxing tube II, and dewaxing tube III. Dewaxing tube II is fixed to the inner wall of the bottom of the furnace body. Dewaxing tube I is connected to dewaxing tube II from the inside of the muffle furnace from top to bottom. Dewaxing tube III is fixed to the outer wall of the bottom of the furnace body and aligned with the center of dewaxing tube II. Dewaxing tube III is equipped with a cooling water jacket, and a baffle plate is welded to the cooling water jacket. The baffle plate is connected to the cooling water jacket and filled with cooling water. The collection tank is connected to a condenser, a Roots pump, and a mechanical pump in sequence through pipes.

2. The anti-backflow collection tank for pressureless sintering silicon carbide vacuum furnace according to claim 1, characterized in that: The dewaxing tube III is made of metal and is connected to the furnace body via a flange, with a vacuum seal in the middle via a sealing ring.

3. The anti-backflow collection tank for pressureless sintering silicon carbide vacuum furnace according to claim 1, characterized in that: The flow deflector is provided in several units, which are inclined downwards at 45 degrees and arranged alternately.

4. The anti-backflow collection tank for pressureless sintering silicon carbide vacuum furnace according to claim 1, characterized in that: The dewaxing cap is screwed onto the dewaxing tube I by threads, and the dewaxing cap has an inverted conical tube inside.

5. The anti-backflow collection tank for pressureless sintering silicon carbide vacuum furnace according to claim 1, characterized in that: The collection tank is connected to the bottom of the dewaxing pipe III via a flange. The collection tank is tilted at 45 degrees and a baffle is installed inside the collection tank.

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