Degreasing and sintering vacuum system and degreasing and sintering method

Abstract

The invention discloses a degreasing and sintering vacuum system and a degreasing and sintering method, and belongs to the technical field of hard alloy production. The degreasing and sintering vacuum system comprises a heat treatment furnace, a first air exhaust circuit, a second air exhaust circuit, an air exhaust pump assembly and a pressure detection assembly, the heat treatment furnace comprises a furnace shell and an inner furnace, the inner furnace is located in the furnace shell, and a heating gap is formed between the inner furnace and the furnace shell. The interior of the inner furnace and the heating gap in the furnace shell can be vacuumized through the first air exhaust path and the second air exhaust path correspondingly, so that the double-layer structure of the heat treatment furnace can be in a double-layer vacuum state. According to the degreasing sintering vacuum system, gas in the heating gap can be prevented from permeating into the inner furnace, the vacuum degree in the inner furnace can be maintained, the gas in the inner furnace can be inhibited from permeating into the heating gap, the risk of process pollution is reduced, and therefore the vacuum sealing reliability of the degreasing sintering vacuum system is enhanced.

Description

Technical Field

[0001] The present application relates to the technical field of cemented carbide production, and in particular to a degreasing and sintering vacuum system and a degreasing and sintering method. Background Art

[0002] A heat treatment furnace is a device used to heat, insulate, and cool metal materials to improve their properties or transform their specific microstructure. Heat treatment furnaces can include vacuum sintering furnaces and vacuum degreasing and sintering furnaces. Vacuum degreasing and sintering furnaces are heat treatment furnaces that perform protective degreasing and sintering on the heated object in a vacuum environment. For example, vacuum degreasing and sintering furnaces can be used for the degreasing and sintering of metal powder compacts.

[0003] A vacuum degreasing sintering furnace usually includes a furnace shell, an inner furnace and a heating element. The inner furnace is located inside the furnace shell. The heating element is usually located in the heating gap between the furnace shell and the inner furnace. The chamber of the inner furnace can be used to place the material to be heated, and the heating element is used to heat the material in the chamber of the inner furnace.

[0004] Currently, when using a vacuum debinding and sintering furnace to heat materials, there is a risk of process contamination during the processing due to the poor reliability of the vacuum seal of the vacuum debinding and sintering furnace;

[0005] In addition, in the process of vacuum debinding and sintering furnace, although the debinding step and the sintering step both require a vacuum environment, due to the significant differences in vacuum requirements, heating conditions and process objectives between the two, the core technical challenge lies in how to achieve it through optimized vacuum piping system design: precise step-by-step control to meet the vacuum level, pumping speed and gas load requirements of different stages; efficient switching and isolation to avoid cross contamination and reduce transition time; system compatibility and reliability to take into account both high-throughput exhaust in the debinding stage and high vacuum stability in the sintering stage. Summary of the Invention

[0006] The present invention provides a degreasing sintering vacuum system and a degreasing sintering method. The technical solution is as follows:

[0007] According to one aspect of the present application, a debinding and sintering vacuum system is provided, comprising:

[0008] Heat treatment furnace, first air extraction path, second air extraction path, air extraction pump assembly and pressure detection assembly;

[0009] The heat treatment furnace comprises a furnace shell and an inner furnace, wherein the inner furnace is located within the furnace shell and has a heating gap with the furnace shell, and the inner furnace is permeable to gas;

[0010] The intake end of the first air extraction path communicates with the heating gap, and the outlet end of the first air extraction path communicates with the air extraction pump assembly;

[0011] The intake end of the second air extraction path communicates with the interior of the inner furnace, and the outlet end of the second air extraction path communicates with the air extraction pump assembly;

[0012] The pressure detection assembly is used to detect the internal pressure of the furnace shell and the internal pressure of the inner furnace.

[0013] Optionally, the intake end of the first air extraction path communicates with the heating gap from the top of the heat treatment furnace, and the intake end of the second air extraction path communicates with the interior of the inner furnace from the lower part of the heat treatment furnace; the inner furnace is made of graphite.

[0014] Optionally, the first air extraction path includes a first pipeline and a first valve. The intake port of the first pipeline is located between the furnace shell and the inner furnace, the outlet port of the first pipeline communicates with the air extraction pump assembly, and the first valve is installed on the first pipeline;

[0015] The second air extraction path includes a second pipeline and a second valve. The intake port of the second pipeline is located in the inner furnace, the outlet port of the second pipeline communicates with the air extraction pump assembly, and the second valve is installed on the second pipeline;

[0016] The air extraction pump assembly includes a Roots pump and a rotary vane pump connected in series. One end of the Roots pump communicates with the outlet ports of the first pipeline and the second pipeline, and the other end of the Roots pump communicates with the rotary vane pump.

[0017] Optionally, the degreasing and sintering vacuum system further includes: a first communication air path and a first adjustment air path connected in parallel;

[0018] The intake ends of the first communication air path and the first adjustment air path are both connected to the outlet ports of the first pipeline and the second pipeline, and the outlet ends of the first communication air path and the first adjustment air path are both connected to the Roots pump;

[0019] The first adjustment air path is used to adjust the gas flow rates of the first pipeline and the second pipeline.

[0020] Optionally, the first communication air path includes a third pipeline and a third valve. The intake port of the third pipeline is connected to the outlet ports of the first pipeline and the second pipeline, the outlet port of the third pipeline is connected to the Roots pump, and the third valve is installed on the third pipeline;

[0021] The first regulating gas path includes a fourth pipeline, a fourth valve, and a proportional valve. The inlet of the fourth pipeline is communicated with the outlets of the first pipeline and the second pipeline. The outlet of the fourth pipeline is communicated with the Roots pump. The fourth valve and the proportional valve are installed in parallel on the fourth pipeline.

[0022] Optionally, the degreasing and sintering vacuum system further includes: a gas storage tank, an inflation gas path, a second communication gas path and a second regulating gas path connected in parallel;

[0023] The gas storage tank is used for storing inert gas;

[0024] The inlet ends of the second communication gas path and the second regulating gas path are both communicated with the gas storage tank. The outlet ends of the second communication gas path and the second regulating gas path are both communicated with the inner furnace through the inflation gas path. The second regulating gas path is used for regulating the gas flow rate of the inflation gas path.

[0025] Optionally, the inflation gas path includes a fifth pipeline and a fifth valve. The outlet of the fifth pipeline is communicated with the inner furnace. The fifth valve is installed on the fifth pipeline;

[0026] The second communication gas path includes a sixth pipeline and a sixth valve. The inlet of the sixth pipeline is communicated with the gas storage tank. The outlet of the sixth pipeline is communicated with the inlet of the fifth pipeline. The sixth valve is installed on the sixth pipeline;

[0027] The second regulating gas path includes a seventh pipeline and a mass flow controller. The inlet of the seventh pipeline is communicated with the gas storage tank. The outlet of the seventh pipeline is communicated with the inlet of the fifth pipeline. The mass flow controller is installed on the seventh pipeline.

[0028] Optionally, the degreasing and sintering vacuum system further includes: an intake pipeline, a seventh valve, a wax collecting cylinder, an outlet pipeline, an eighth valve and a mold temperature controller;

[0029] Both ends of the intake pipeline are respectively communicated with the inner furnace and the wax collecting cylinder. The seventh valve is installed on the intake pipeline;

[0030] Both ends of the outlet pipeline are respectively communicated with the wax collecting cylinder and the rotary vane pump. The eighth valve is installed on the outlet pipeline;

[0031] The mold temperature controller is communicated with the wax collecting cylinder.

[0032] Optionally, the heat treatment furnace further includes: a heating element. The degreasing and sintering vacuum system further includes: a cooling fan, cooling fins and a cooling water path;

[0033] The heating element is located in the heating gap;

[0034] The cooling fan is located inside the furnace shell and at one end of the inner furnace;

[0035] The cooling fins are located between the cooling fan and the inner furnace;

[0036] The cooling water path is in communication with the cooling fins.

[0037] According to another aspect of the present application, there is provided a degreasing and sintering method for use in the above-mentioned degreasing and sintering vacuum system, the method comprising:

[0038] Opening the first air extraction path to evacuate the interior of the heat treatment furnace;

[0039] Performing a vacuum test on the heat treatment furnace through the pressure detection component;

[0040] Turning on the heating element in the heat treatment furnace to heat the material, and turning on at least one of the first air extraction path and the second air extraction path to perform vacuum sintering treatment on the material;

[0041] Turning off the heating element and the at least one air extraction path in the heat treatment furnace.

[0042] The beneficial effects brought by the technical solution provided in the embodiments of the present application at least include:

[0043] There is provided a degreasing and sintering vacuum system including a heat treatment furnace, a first air extraction path, a second air extraction path, an air extraction pump assembly, and a pressure detection component. Among them, the heat treatment furnace includes a furnace shell and an inner furnace. The inner furnace is located inside the furnace shell and has a heating gap therebetween. The intake end of the first air extraction path can be in communication with the heating gap, and the intake end of the second air extraction path can be in communication with the interior of the inner furnace. The outlet ends of the first air extraction path and the second air extraction path are both in communication with the air extraction pump assembly. In this way, through the first air extraction path and the second air extraction path, the interior of the inner furnace and the heating gap inside the furnace shell can be evacuated respectively, so that the double-layer structure of the heat treatment furnace can be in a double-layer vacuum state. It can prevent the gas in the heating gap from penetrating into the inner furnace, maintain the vacuum degree in the inner furnace, and also inhibit the gas in the inner furnace from penetrating into the heating gap, reducing the risk of process pollution, thereby enhancing the vacuum sealing reliability of the degreasing and sintering vacuum system.

[0044] Moreover, if the material can release combustible gas during sintering, the second air extraction path can timely extract the combustible gas, which can prevent the accumulation of combustible gas in the heating gap, reduce the risk of explosion of the heat treatment furnace, and improve the safety of the debinding and sintering vacuum system. In addition, the double-layer vacuum state can form a double heat insulation barrier. That is, by evacuating the inside of the inner furnace, the gas convection and heat conduction in the heat-insulated inner box can be reduced, and the heat loss on the material can be reduced; by evacuating the heating gap, the heat radiation and conduction paths to the outside of the furnace shell can be further blocked, and the temperature uniformity inside the heat treatment furnace can be improved.

[0045] Moreover, by combining a roots pump and a rotary vane pump into an air extraction pump group, with the rotary vane pump as the fore pump and the roots pump as the booster pump, first the rotary vane pump is used to evacuate the heat treatment furnace from atmospheric pressure to the starting pressure of the roots pump, and then the roots pump is used to quickly increase the vacuum degree to the target vacuum degree, which can improve the air extraction efficiency. The rotary vane pump can be equipped with an air ballast valve, which can improve the efficiency of the rotary vane pump in handling condensable gases (such as water vapor, solvent vapor, etc.) and prevent the condensable gases from condensing and contaminating the pump oil in the rotary vane pump.

[0046] In addition, the intake end of the first air extraction path communicates with the heating gap from the top of the heat treatment furnace, and the intake end of the second air extraction path communicates with the inside of the inner furnace from the lower part of the heat treatment furnace. Thus, it is possible to evacuate the upper part of the heating gap to efficiently capture the heating gas, conform to the natural convection law, and reduce the air extraction energy consumption; evacuating the lower part of the inner furnace can stably extract denser gases or particulate matters (such as unevaporated sediments).

[0047] Furthermore, by additionally setting up a debinding component for vacuum debinding, it is independently set relative to the vacuum pipelines (the first air extraction path and the second air extraction path) used in the sintering step, which can prevent the oil wax from contaminating the vacuum pipelines and affecting the service life of the vacuum pipelines and the vacuum detection components; and the roots pump can be used as both the vacuum pump of the debinding component and the fore pump for the high vacuum conditions required for vacuum debinding. Thus, step-by-step precise control can be achieved to meet the vacuum degree, pumping speed, and gas load requirements in different stages; efficient switching and isolation can be realized to avoid a large amount of pollution generated during debinding and reduce the transition time; and the high-throughput exhaust during the debinding stage and the high vacuum stability during the sintering stage can be taken into account. Description of the Drawings

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0049] Figure 1It is a schematic structural diagram of a degreasing sintering vacuum system provided by an embodiment of the present application;

[0050] Figure 2 It is a schematic structural diagram of a heat treatment furnace provided by an embodiment of the present application;

[0051] Figure 3 It is a schematic structural diagram of another degreasing sintering vacuum system provided by an embodiment of the present application;

[0052] Figure 4 It is a schematic flow diagram of a degreasing sintering method provided by an embodiment of the present application;

[0053] Figure 5 It is a schematic flow diagram of another degreasing sintering method provided by an embodiment of the present application;

[0054] Figure 6 It is a schematic diagram of gas flow in a vacuum test provided by an embodiment of the present application;

[0055] Figure 7 It is a schematic diagram of gas flow in another vacuum test provided by an embodiment of the present application;

[0056] Figure 8 It is a schematic diagram of gas flow in a dewaxing treatment provided by an embodiment of the present application;

[0057] Figure 9 It is a schematic diagram of gas flow in a sintering treatment under vacuum extraction provided by an embodiment of the present application;

[0058] Figure 10 It is a schematic diagram of gas flow in a full vacuum extraction sintering treatment provided by an embodiment of the present application;

[0059] Figure 11 It is a schematic diagram of gas flow in an upper vacuum extraction sintering treatment provided by an embodiment of the present application;

[0060] Figure 12 It is a schematic diagram of gas flow in a partial pressure sintering treatment provided by an embodiment of the present application;

[0061] Figure 13 It is a schematic diagram of gas flow in a partial pressure sintering treatment provided by an embodiment of the present application. Detailed implementation manners

[0062] To make the objectives, technical solutions, and advantages of the present application clearer, the following will further describe the embodiments of the present application in detail with reference to the accompanying drawings.

[0063] Although the present application can be easily embodied in various forms of embodiments, only some specific embodiments are shown in the drawings and will be described in detail in this specification. At the same time, it can be understood that this specification should be regarded as a demonstrative illustration of the principles of the present application and is not intended to limit the present application to what is described herein.

[0064] Thus, a feature pointed out in this specification will be used to illustrate one of the features of an embodiment of the present application, rather than implying that each embodiment of the present application must have the feature described. In addition, it should be noted that this specification describes many features. Although some features can be combined together to show possible system designs, these features can also be used in other combinations not explicitly described. Thus, unless otherwise stated, the described combinations are not intended to be limiting.

[0065] In the embodiments shown in the drawings, the indication of directions (such as up, down, left, right, front and back) is used to explain that the structures and movements of various elements of the present application are not absolute but relative. When these elements are in the positions shown in the drawings, these explanations are appropriate. If the description of the positions of these elements changes, then the indication of these directions also changes accordingly.

[0066] Please refer to Figure 1 and Figure 2 , Figure 1 is a schematic structural diagram of a degreasing sintering vacuum system provided by an embodiment of the present application, Figure 2 is a schematic structural diagram of a heat treatment furnace 101 provided by an embodiment of the present application. The degreasing sintering vacuum system may include: a heat treatment furnace 101, a first pumping path 102, a second pumping path 103, a pumping pump assembly 104 and a pressure detection assembly 105.

[0067] The heat treatment furnace 101 may include a furnace shell 1011 and an inner furnace 1012. The inner furnace 1012 is located inside the furnace shell 1011 and has a heating gap x1 between it and the furnace shell 1011. The inner furnace 1012 can permeate gas. The inner furnace 1012 can be called a muffle furnace. The heat treatment furnace 101 may further include a heating element 1013 and a heat insulation layer. The heating element 1013 may be located outside the inner furnace 1012, that is, in the heating gap x1. The heat insulation layer may be located between the heating element 1013 and the furnace shell 1011, and also in the heating gap x1. The inner furnace 1012 has a certain air permeability at high temperature or in a vacuum state. That is, some of the gas in the inner furnace 1012 may permeate into the heating gap x1 through the inner furnace 1012, and the gas in the heating gap x1 may also permeate into the inner furnace 1012.

[0068] The intake end of the first air extraction path 102 can communicate with the heating gap x1, and the outlet end of the first air extraction path 102 communicates with the air extraction pump assembly 104. The intake end of the first air extraction path 102 can be located in the heating gap x1 between the furnace shell 1011 and the inner furnace 1012. When the air extraction pump assembly 104 extracts air through the first air extraction path 102, the gas in the heating gap x1 between the furnace shell 1011 and the inner furnace 1012 can be extracted and discharged into a preset space, which can refer to the exhaust duct or the external environment.

[0069] The intake end of the second air extraction path 103 can communicate with the interior of the inner furnace 1012, and the outlet end of the second air extraction path 103 communicates with the air extraction pump assembly 104. The intake end of the second air extraction path 103 can be located inside the inner furnace 1012. When the air extraction pump assembly 104 extracts air through the second air extraction path 103, the gas inside the inner furnace 1012 can be extracted and discharged into a preset space.

[0070] The pressure detection assembly 105 can be used to detect the internal pressure of the furnace shell 1011 and the internal pressure of the inner furnace 1012. The heat treatment furnace 101 can be of a double-layer structure, and the pressure detection assembly 105 can detect the pressure in each layer structure of the heat treatment furnace 101. Exemplarily, the pressure detection assembly 105 can include multiple pressure sensors or multiple pressure transmitters.

[0071] In the degreasing and sintering vacuum system of the embodiments of the present application, the interior of the inner furnace 1012 and the heating gap x1 inside the furnace shell 1011 can be evacuated separately through the first air extraction path 102 and the second air extraction path 103, so that the double-layer structure of the heat treatment furnace 101 is in a double-layer vacuum state. It can be understood that in the degreasing and sintering process, the first air extraction path 102 or the second air extraction path 103 can be used alone, or the first air extraction path 102 and the second air extraction path 103 can be used simultaneously, which can improve the process flexibility of the degreasing and sintering vacuum system.

[0072] In summary, the embodiment of the present application provides a degreasing and sintering vacuum system including a heat treatment furnace 101, a first air extraction path 102, a second air extraction path 103, an air extraction pump assembly 104, and a pressure detection assembly 105. Among them, the heat treatment furnace 101 includes a furnace shell 1011 and an inner furnace 1012. The inner furnace 1012 is located inside the furnace shell 1011 and has a heating gap x1 between it and the furnace shell 1011. The intake end of the first air extraction path 102 can be communicated with the heating gap x1, and the intake end of the second air extraction path 103 can be communicated with the inside of the inner furnace 1012. The outlet ends of the first air extraction path 102 and the second air extraction path 103 are both communicated with the air extraction pump assembly 104. In this way, through the first air extraction path 102 and the second air extraction path 103, the inside of the inner furnace 1012 and the heating gap x1 inside the furnace shell 1011 can be evacuated respectively, so that the double-layer structure of the heat treatment furnace 101 can be in a double-layer vacuum state. It can prevent the gas in the heating gap x1 from penetrating into the inner furnace 1012, maintain the vacuum degree in the inner furnace 1012, and also inhibit the gas in the inner furnace 1012 from penetrating into the heating gap x1, reducing the risk of process pollution, thereby enhancing the vacuum sealing reliability of the degreasing and sintering vacuum system.

[0073] Moreover, if the material 30 can release combustible gas during sintering, the first air extraction path 102 can timely extract the combustible gas. The first air extraction path 102 can prevent the combustible gas from accumulating in the heating gap x1, reduce the risk of explosion of the heat treatment furnace 101, and improve the safety of the degreasing and sintering vacuum system. In addition, the double-layer vacuum state can form a double heat insulation barrier. That is, by evacuating the inside of the inner furnace 1012, the gas convection and heat conduction in the heat-insulating inner box can be reduced, and the heat loss on the material 30 can be reduced; by evacuating the heating gap x1, the heat radiation and conduction paths to the outside of the furnace shell 1011 can be further blocked, and the temperature uniformity inside the heat treatment furnace 101 can be improved.

[0074] Please refer to Figure 2 , in an optional embodiment, the material of the inner furnace 1012 may include graphite. Graphite has good stability and heat conduction performance at high temperatures. Since graphite is sintered from carbon particles, there are micron-sized pores on the inner furnace 1012 made of graphite material. Therefore, at normal temperature and pressure, the pores on the inner furnace 1012 may cause trace gas penetration, and at high temperature or high vacuum state, the gas permeability of the inner furnace 1012 will be increased.

[0075] In an alternative embodiment, the intake end of the first air extraction path 102 communicates with the heating gap x1 from the top of the heat treatment furnace 101, and the intake end of the second air extraction path 103 communicates with the interior of the inner furnace 1012 from the lower part of the heat treatment furnace 101. In this way, it is possible to evacuate the upper part of the heating gap x1 to efficiently capture the heating gas, conforming to the natural convection law and reducing the air extraction energy consumption; evacuating the lower part of the inner furnace 1012 can stably extract denser gases or particulate matters (such as unevaporated deposits).

[0076] In an exemplary embodiment, the inner furnace 1012 may include a cylindrical box body t1 and end caps t2 located at both ends of the box body t1. The cylindrical box body t1 and the two end caps t2 may both be made of graphite.

[0077] Please refer to Figure 1 , in an alternative real-time mode, the first air extraction path 102 may include a first pipeline 1021 and a first valve 1022. The intake port of the first pipeline 1021 is located between the furnace shell 1011 and the inner furnace 1012. The outlet of the first pipeline 1021 is communicated with the air extraction pump assembly 104, and the first valve 1022 is installed on the first pipeline 1021. The intake port of the first pipeline 1021 is communicated with the heating gap x1, and the first valve 1022 can control the shut-off and opening of the first pipeline 1021. Exemplarily, the first valve 1022 may include an electromagnetic valve, a pneumatic valve, etc.

[0078] The second air extraction path 103 may include a second pipeline 1031 and a second valve 1032. The intake port of the second pipeline 1031 is located in the inner furnace 1012. The outlet of the second pipeline 1031 is communicated with the air extraction pump assembly 104, and the second valve 1032 is installed on the second pipeline 1031. The intake port of the second pipeline 1031 is communicated with the interior of the inner furnace 1012, and the second valve 1032 can control the shut-off and opening of the second pipeline 1031. Exemplarily, the second valve 1032 may include an electromagnetic valve, a pneumatic valve, etc.

[0079] The air extraction pump assembly 104 may include a Roots pump 1041 and a rotary vane pump 1042 connected in series. One end of the Roots pump 1041 is communicated with the outlet of the first pipeline 1021 and the outlet of the second pipeline 1031. The other end of the Roots pump 1041 is communicated with the rotary vane pump 1042. The intake end of the rotary vane pump 1042 is communicated with the Roots pump 1041, and the outlet end of the rotary vane pump 1042 is communicated with the exhaust pipeline or the external environment.

[0080] Due to the phenomenon that the pumping speed of the rotary vane pump 1042 can decrease as the pressure drops, the roots pump 1041 cannot be started alone from atmospheric pressure. Therefore, by combining the roots pump 1041 and the rotary vane pump 1042 into a pumping pump, with the rotary vane pump 1042 as the fore pump and the roots pump 1041 as the booster pump, first use the rotary vane pump 1042 to pump the heat treatment furnace 101 from atmospheric pressure to the starting pressure of the roots pump 1041, and then use the roots pump 1041 to quickly increase the vacuum degree to the target vacuum degree, which can improve the pumping efficiency.

[0081] The rotary vane pump 1042 can be equipped with a gas ballast valve z1, which can improve the efficiency of the rotary vane pump 1042 in handling condensable gases (such as water vapor, solvent vapor, etc.) and prevent the condensable gases from condensing and contaminating the pump oil in the rotary vane pump 1042.

[0082] In an exemplary embodiment, the furnace shell 1011 has a first through hole, and the intake port of the first pipeline 1021 extends into the furnace shell 1011 through the first through hole; the furnace shell 1011 also has a second through hole, and the inner furnace 1012 has a third through hole, and the intake port of the second pipeline 1031 extends into the inner furnace 1012 through the second through hole and the third through hole; wherein, the first through hole is located on the side of the furnace shell 1011 away from the ground, the second through hole is located on the side of the furnace shell 1011 close to the ground, and the third through hole is located on the side of the inner furnace 1012 close to the ground.

[0083] Please refer to Figure 3 , Figure 3 FIG. is a schematic structural diagram of another degreasing and sintering vacuum system provided by an embodiment of the present application. In an optional embodiment, the degreasing and sintering vacuum system may further include: a first communication gas path 106 and a first adjustment gas path 107 connected in parallel. The intake ends of the first communication gas path 106 and the first adjustment gas path 107 are both connected to the outlet of the first pipeline 1021 and the outlet of the second pipeline 1031, and the outlet ends of the first communication gas path 106 and the first adjustment gas path 107 are both connected to the roots pump 1041; the first adjustment gas path 107 is used to adjust the gas flow rates of the first pipeline 1021 and the second pipeline 1031. Both the first pipeline 1021 and the second pipeline 1031 can be connected to the pumping pump assembly 104 through at least one of the first communication gas path 106 and the first adjustment gas path 107, which can improve the flexibility of the pumping direction.

[0084] Please refer to Figure 3, in an alternative embodiment, the first communication gas path 106 may include a third pipeline 1061 and a third valve 1062. The inlet of the third pipeline 1061 is communicated with the outlets of the first pipeline 1021 and the second pipeline 1031. The outlet of the third pipeline 1061 is communicated with the Roots pump 1041. The third valve 1062 is installed on the third pipeline 1061. The third valve 1062 can control the shut-off and opening of the third pipeline 1061. Exemplarily, the third valve 1062 may include a solenoid valve, a pneumatic valve, etc.

[0085] The first regulating gas path 107 may include a fourth pipeline 1071, a fourth valve 1072, and a proportional valve 1073. The inlet of the fourth pipeline 1071 is communicated with the outlets of the first pipeline 1021 and the second pipeline 1031. The outlet of the fourth pipeline 1071 is communicated with the Roots pump 1041. The fourth valve 1072 and the proportional valve 1073 are installed in parallel on the fourth pipeline 1071. The fourth valve 1072 can control the shut-off and opening of the fourth pipeline 1071. Exemplarily, the fourth valve 1072 may include a solenoid valve, a pneumatic valve, etc. The proportional valve 1073 can be used to control the gas flow rate in the fourth pipeline 1071. Exemplarily, the proportional valve 1073 may include an electromagnetic proportional valve 1073, an electric proportional valve 1073, etc.

[0086] Please refer to Figure 3 , in an alternative embodiment, the degreasing and sintering vacuum system may further include an inflation assembly. The inflation assembly may include: a gas storage tank 108, an inflation gas path 109, a second communication gas path 110 and a second regulating gas path 111 connected in parallel; the gas storage tank 108 is used for storing inert gas; the inlet ends of the second communication gas path 110 and the second regulating gas path 111 are both communicated with the gas storage tank 108, and the outlet ends of the second communication gas path 110 and the second regulating gas path 111 are both communicated with the inner furnace 1012 through the inflation gas path 109. The second regulating gas path 111 is used for regulating the gas flow rate of the inflation gas path 109. Among them, the inert gas may include argon (Ar). When it is necessary to adjust the inflation flow rate of the inert gas, a preset flow rate of gas can be delivered to the inflation gas path 109 through the second regulating gas path 111. When it is not necessary to adjust the inflation flow rate of the inert gas, a preset flow rate of gas can be delivered to the inflation gas path 109 through the second communication gas path 110. In this way, the operating cost can be reduced.

[0087] Please refer to Figure 3, in an alternative embodiment, the inflation gas path 109 may include a fifth pipeline 1091 and a fifth valve 1092. The outlet of the fifth pipeline 1091 communicates with the inner furnace 1012, and the fifth valve 1092 is installed on the fifth pipeline 1091; the fifth valve 1092 can control the shut-off and opening of the fifth pipeline 1091. Exemplarily, the fifth valve 1092 may include an electromagnetic valve, a pneumatic valve, etc.

[0088] The second communication gas path 110 includes a sixth pipeline 1101 and a sixth valve 1102. The inlet of the sixth pipeline 1101 communicates with the gas storage tank 108, the outlet of the sixth pipeline 1101 communicates with the inlet of the fifth pipeline 1091, and the sixth valve 1102 is installed on the sixth pipeline 1101. The sixth valve 1102 can control the shut-off and opening of the sixth pipeline 1101. Exemplarily, the sixth valve 1102 may include an electromagnetic valve, a pneumatic valve, etc.

[0089] The second adjustment gas path 111 includes a seventh pipeline and a mass flow controller 1112. The inlet of the seventh pipeline communicates with the gas storage tank 108, the outlet of the seventh pipeline communicates with the inlet of the fifth pipeline 1091, and the mass flow controller 1112 is installed on the seventh pipeline. The mass flow controller 1112 is a device for precisely measuring and controlling the gas flow rate. It can automatically control the gas flow rate and keep the flow rate unchanged at the set value even when the system pressure fluctuates or the ambient temperature changes. The mass flow controller 1112 can be used to adjust the gas flow rate in the seventh pipeline.

[0090] Please refer to Figure 3 , in an alternative embodiment, the debinding and sintering vacuum system may further include a wax collection assembly. The wax collection assembly may include: an intake pipeline 112, a seventh valve 113, a wax collection cylinder 114, an outlet pipeline 115, an eighth valve 116, and a mold temperature controller 117; both ends of the intake pipeline 112 communicate with the inner furnace 1012 and the wax collection cylinder 114 respectively, and the seventh valve 113 is installed on the intake pipeline 112; both ends of the outlet pipeline 115 communicate with the wax collection cylinder 114 and the rotary vane pump 1042 respectively, and the eighth valve 116 is installed on the outlet pipeline 115; the mold temperature controller 117 communicates with the wax collection cylinder 114. When the debinding and sintering vacuum system in the embodiment of the present application works, the high-temperature gas in the inner furnace 1012 first enters the wax collection cylinder 114 from the intake pipeline 112 for cooling and liquefaction, and then is discharged from the outlet pipeline 115; the liquefied liquid is collected in the wax collection cylinder 114 and discharged from the drain pipe of the wax collection cylinder 114. The mold temperature controller 117 controls the temperature inside the wax collection cylinder 114 by circulating a heat transfer medium (oil or water) to ensure that the temperature inside the wax collection cylinder 114 is uniform.

[0091] Please refer to Figure 2, in an alternative embodiment, the heat treatment furnace 101 may further include: a heating element 1013. The degreasing and sintering vacuum system may further include a cooling assembly, and the cooling assembly may include: a cooling fan 118, cooling fins 119, and a cooling water circuit 120. The heating element 1013 may include a graphite rod, a molybdenum-tungsten alloy rod, a silicon carbide rod, etc.

[0092] The heating element 1013 is located in the heating gap x1 and is used to supply heat to the inner furnace 1012; the cooling fan 118 is located inside the furnace shell 1011 and at one end of the inner furnace 1012; the cooling fins 119 are located between the cooling fan 118 and the inner furnace 1012; the cooling water circuit 120 is in communication with the cooling fins 119. Both the cooling fan 118 and the cooling fins 119 may be installed inside the furnace shell 1011. Exemplarily, both the cooling fan 118 and the cooling fins 119 may be bolted to the furnace shell 1011. The cooling water circuit 120 may be in communication with a cooling water source, and the cooling water source may include a water storage tank or a water supply pipe.

[0093] Please refer to Figure 3 , in an exemplary embodiment, the pressure detection assembly 105 may include a first pressure sensor 1051, a second pressure sensor 1052, a third pressure sensor 1053, a fourth pressure sensor 1054, and a fifth pressure sensor 1055. The first pressure sensor 1051, the second pressure sensor 1052, and the third pressure sensor 1053 are all in communication with the heating gap x1 to detect the pressure in the heating gap x1. The first pressure sensor 1051, the second pressure sensor 1052, and the third pressure sensor 1053 are three pressure sensors with different ranges. Among them, the unit of the measurement result of the first pressure sensor 1051 is pascal (Pa), the unit of the measurement result of the second pressure sensor 1052 is millibar (mbar), and the unit of the measurement result of the third pressure sensor 1053 is kilopascal (kPa). The fourth pressure sensor 1054 is installed on the intake pipe 112 to detect the pressure in the inner furnace 1012, and the unit of the measurement result of the fourth pressure sensor 1054 is millibar (mbar). The fifth pressure sensor 1055 is installed on the outlet pipe 115 to detect the pressure in the wax collection cylinder 114, and the unit of the measurement result of the fifth pressure sensor 1055 is millibar (mbar).

[0094] The debinding sintering vacuum system may further include a temperature detection component. The temperature detection component may include a first temperature sensor 1211, a second temperature sensor 1212, and a third temperature sensor 1213. The first temperature sensor 1211 is installed on the intake pipeline 112 for detecting the internal temperature of the intake pipeline 112. The second temperature sensor 1212 is installed on the wax collection cylinder 114 for detecting the internal temperature of the wax collection cylinder 114. The third temperature sensor 1213 is installed on the rotary vane pump 1042 for detecting the internal temperature of the rotary vane pump 1042.

[0095] The debinding sintering vacuum system further includes a PLC control component and a touch display interaction terminal. The PLC control component may store a preset process flow and may be electrically connected to multiple valves, the heating element 1013, the temperature detection component, the wax collection cylinder 114, and other components, so that the debinding sintering vacuum system operates according to the preset process flow. The touch display interaction terminal may have a parameter setting interface, and an operator may input process parameters through the parameter setting interface.

[0096] Please refer to Figure 4 and Figure 1 , Figure 4 is a schematic flow chart of a debinding sintering method provided by an embodiment of the present application. The embodiment of the present application further provides a debinding sintering method, which is used for the debinding sintering vacuum system in any of the above embodiments. The method includes the following steps:

[0097] Step 201: Open the first air extraction path to evacuate the inside of the heat treatment furnace.

[0098] Step 202: Conduct a vacuum test on the heat treatment furnace through the pressure detection component.

[0099] Step 203: Turn on the heating element in the heat treatment furnace to heat the material, and turn on at least one of the first air extraction path and the second air extraction path to conduct vacuum sintering on the material.

[0100] Step 204: Turn off the heating element and at least one air path in the heat treatment furnace.

[0101] Please refer to Figure 5 , Figure 5 is a schematic flow chart of another debinding sintering method provided by an embodiment of the present application. The embodiment of the present application further provides a debinding sintering method, which is used for the debinding sintering vacuum system in any of the above embodiments. The method includes the following steps:

[0102] Step 301: Open the first air extraction path to evacuate the inside of the heat treatment furnace.

[0103] Please refer to Figure 6 , Figure 6It is a schematic diagram of gas flow for vacuum testing provided by an embodiment of the present application. An operator can manually start the rotary vane pump 1042, open the first valve 1022 on the first pipeline 1021, and open the fourth valve 1072 and the proportional valve 1073 on the fourth pipeline 1071 to extract the air inside the heat treatment furnace 101. At this time, the furnace shell 1011 in the heat treatment furnace 101 is in a closed state, and the inner furnace 1012 is in an open state, that is, the end cover t2 of the inner furnace 1012 is in an open state so that the inner furnace 1012 is connected to the heating gap x1. Meanwhile, open the eighth valve 116 on the air outlet pipeline 115 to extract the residual gas in the wax collecting cylinder 114.

[0104] Please refer to Figure 7 , Figure 7 It is another schematic diagram of gas flow for vacuum testing provided by an embodiment of the present application. When the pressure inside the heat treatment furnace 101 is detected by the second pressure sensor 1052 to reach 20 mbar, open the third valve 1062 on the third pipeline 1061, and close the fourth valve 1072 and the proportional valve 1073 on the fourth pipeline 1071.

[0105] When the pressure inside the heat treatment furnace 101 continuously remains lower than 20 mbar, close the eighth valve 116 on the air outlet pipeline 115, and after a 30 - second delay, start the roots pump 1041.

[0106] Step 302: Conduct a vacuum test on the heat treatment furnace through the pressure detection component.

[0107] When the pressure inside the heat treatment furnace 101 is detected by the first pressure sensor 1051 to reach the vacuum test vacuum degree, close the third pipeline 1061, the third valve 1062, and the roots pump 1041, and conduct a 1 - minute leak test on the heat treatment furnace 101 through the pressure detection component 105; among them, the vacuum test vacuum degree can be preset by the operator in the touch - screen parameter setting interface. Exemplarily, the vacuum test vacuum degree is 1 Pa - 3 Pa.

[0108] If the pressure inside the heat treatment furnace 101 rises by less than or equal to the vacuum test allowable leakage value after 1 minute, it indicates that the test is qualified, and execute step 303; if the pressure inside the heat treatment furnace 101 rises by more than the vacuum test allowable leakage value after 1 minute, execute step 301 and step 302 again after a 1 - minute delay. If the test is qualified, execute step 303, otherwise send a vacuum test failure signal to the PLC control component. Among them, the vacuum test allowable leakage value can be preset by the operator in the touch - screen parameter setting interface. Exemplarily, the vacuum test allowable leakage value is 1 Pa.

[0109] Step 303: Turn on the heating element and the wax collecting component to perform dewaxing treatment on the material.

[0110] Please refer to Figure 8 , Figure 8 which is a schematic diagram of gas flow for dewaxing treatment provided by an embodiment of the present application. First, the air ballast valve z1 on the rotary vane pump 1042 can be opened, the rotary vane pump 1042 can be started, the roots pump 1041 can be closed, and the eighth valve 116 on the air outlet pipe 115 can be opened to evacuate the wax collection cylinder 114 to a vacuum state. That is, when the pressure value of the measurement result of the fifth pressure sensor 1055 is lower than 2 mbar, it can be considered that the wax collection cylinder 114 is in a vacuum state.

[0111] Then, the fifth valve 1092 on the fifth pipeline 1091 is opened. When the measurement value of the fifth pressure sensor 1055 is lower than 2 mbar and the measurement value of the fourth pressure sensor 1054 is less than 3 mbar, the seventh valve 113 on the air inlet pipe 112 and the sixth valve 1102 on the sixth pipeline 1101 are opened to fill argon into the heat treatment furnace 101 through the air inlet above the heat treatment furnace 101. Exemplarily, a flow meter can be provided at the outlet of the gas storage tank 108, and the flow rate of the gas entering the heat treatment furnace 101 can be adjusted through the flow meter.

[0112] When it is detected by the second pressure sensor 1052 that the pressure in the heat treatment furnace 101 is greater than 4 mbar, the heating element 1013 is started to heat the inside of the heat treatment furnace 101. The degreasing sintering vacuum system can also include a program regulator, which can be electrically connected to the PLC control component. The program regulator pre-stores a degreasing process program, and the dewaxing treatment of the material 30 can be carried out by starting the process program in the program regulator. The temperature rise curve can be recorded and displayed on the touch display interactive terminal to facilitate the operator to observe the operation of the equipment.

[0113] Step 304: Start the heating element and the second air extraction path to perform vacuum under-pumping sintering treatment on the material.

[0114] Please refer to Figure 9 , Figure 9 which is a schematic diagram of gas flow for vacuum under-pumping sintering treatment provided by an embodiment of the present application. First, the rotary vane pump 1042 is opened, the fourth valve 1072 and the proportional valve 1073 on the fourth pipeline 1071 are opened, the eighth valve 116 on the air outlet pipe 115 is opened, and the second valve 1032 on the second pipeline 1031 is opened. When it is detected by the second pressure sensor 1052 that the pressure in the heat treatment furnace 101 reaches 20 mbar, the fourth valve 1072 and the proportional valve 1073 on the fourth pipeline 1071 are closed, the eighth valve 116 on the air outlet pipe 115 is closed, the third valve 1062 on the third pipeline 1061 is opened, and the roots pump 1041 is started after a delay of 10 s until the vacuum sintering process is completed.

[0115] Step 305: Turn on the heating element, the first air extraction path, and the second air extraction path, and perform vacuum full-extraction sintering treatment on the material.

[0116] Please refer to Figure 10 , Figure 10 FIG. is a schematic diagram of gas flow in a vacuum full-extraction sintering process provided by an embodiment of the present application. First, turn on the rotary vane pump 1042, open the fourth valve 1072 and the proportional valve 1073 on the fourth pipeline 1071, open the eighth valve 116 on the air outlet pipeline 115, open the second valve 1032 on the second pipeline 1031, and open the first valve 1022 on the first pipeline 1021. When the pressure in the heat treatment furnace 101 detected by the second pressure sensor 1052 reaches 20 mbar, close the fourth valve 1072 and the proportional valve 1073 on the fourth pipeline 1071, close the eighth valve 116 on the air outlet pipeline 115, open the third valve 1062 on the third pipeline 1061, and start the roots pump 1041 after a 10S delay until the vacuum sintering process is completed.

[0117] Step 306: Turn on the heating element and the first air extraction path, and perform vacuum upward-extraction sintering treatment on the material.

[0118] Please refer to Figure 11 , Figure 11 FIG. is a schematic diagram of gas flow in a vacuum upward-extraction sintering process provided by an embodiment of the present application. First, turn on the rotary vane pump 1042, open the fourth valve 1072 and the proportional valve 1073 on the fourth pipeline 1071, open the eighth valve 116 on the air outlet pipeline 115, and open the first valve 1022 on the first pipeline 1021. When the pressure in the heat treatment furnace 101 detected by the second pressure sensor 1052 reaches 20 mbar, close the fourth valve 1072 and the proportional valve 1073 on the fourth pipeline 1071, close the eighth valve 116 on the air outlet pipeline 115, open the third valve 1062 on the third pipeline 1061, and start the roots pump 1041 after a 10S delay until the vacuum sintering process is completed.

[0119] Step 307: Turn on the heating element, the gas charging assembly, and the first regulating air path, and perform partial-pressure sintering treatment on the material.

[0120] Among them, partial-pressure sintering is a sintering process carried out under specific atmosphere conditions. This process controls the partial pressure of the gas in the sintering environment to regulate the sintering behavior, microstructure, and final properties of the material.

[0121] Please refer to Figure 3, in an exemplary embodiment, when the temperature in the heat treatment furnace 101 rises and it is in a vacuum state, the inner furnace 1012 made of graphite will thermally expand, causing the pores on the inner furnace 1012 to slightly expand. Moreover, the mean free path of gas molecules increases, making it easier for gas to diffuse through the graphite pores. That is, the gas permeability on both sides of the inner furnace 1012 is improved. In this case, argon can be filled into the heating gap x1 through the second communication gas path 110 or the second adjustment gas path 111. The argon located in the heating gap x1 can penetrate into the interior of the inner furnace 1012 under the action of the pressure difference to stably adjust the gas pressure in the sintering atmosphere in the inner furnace 1012. Thus, the function of partial pressure sintering can be achieved, and the sudden change of the vacuum degree in the inner furnace 1012 can be avoided, which can enhance the safety of the debinding sintering vacuum system.

[0122] Please refer to Figure 12 , Figure 12 is a schematic diagram of gas flow for a partial pressure sintering process provided by an embodiment of the present application. First, turn on the rotary vane pump 1042, open the fifth valve 1092 on the fifth pipeline 1091, open the sixth valve 1102 on the sixth pipeline 1101, and open the fourth valve 1072 and the proportional valve 1073 on the fourth pipeline 1071. The opening degree of the proportional valve 1073 is controlled by the second pressure sensor 1052 and the vacuum degree control instrument to control the pressure in the heat treatment furnace 101 within a set range.

[0123] It can be understood that since the material of the inner furnace 1012 is graphite, when argon is filled into the furnace shell 1011 through the sixth pipeline 1101 and the fifth pipeline 1091, the argon in the furnace shell 1011 can penetrate into the inner furnace 1012, thereby uniformly adjusting the gas pressure in the inner furnace 1012 and avoiding the sudden change of the gas pressure in the inner furnace.

[0124] It can be understood that when actually using the debinding sintering method of the embodiment of the present application, the operator can adaptively select and adjust the process steps according to the materials and production environment, and the embodiment of the present application does not limit this. Exemplarily, in the same process, any one of the above steps 304, 305, 306, and 307 can be selected to perform the sintering process; or, at least two of the above steps 304, 305, 306, and 307 can be selected for combination, and the combined process steps can be executed.

[0125] Exemplarily, in one process, step 304 can be first executed to perform vacuum under-drawing sintering treatment on the material. After step 304 has been executed for a period of time, step 306 is executed while step 304 is being executed to simultaneously perform vacuum under-drawing sintering treatment and vacuum over-drawing sintering treatment on the material, so as to avoid process contamination caused by the gas permeating out of the inner furnace. Then, the execution of step 304 and step 306 is stopped, and step 307 is executed to perform partial pressure sintering on the material, so as to improve the mechanical properties (such as hardness and strength) of the sintered part through partial pressure sintering treatment.

[0126] Step 308: Turn on the inflation component and the cooling component to perform cooling treatment on the material.

[0127] Please refer to Figure 13 and Figure 2 , Figure 13 is a schematic diagram of gas flow for a cooling treatment provided by an embodiment of the present application. First, when the temperature inside the heat treatment furnace 101 drops to the set temperature at which the end cover t2 of the inner furnace 1012 can be opened, the solenoid valve (not shown in the figure) on the cooling water circuit 120 is opened. After 10S, the end cover t2 of the inner furnace 1012 is opened, the fifth valve 1092 on the fifth pipeline 1091 is opened, and the mass flow controller 1112 on the seventh pipeline is opened to fill argon into the heat treatment furnace 101, and the pressure inside the heat treatment furnace 101 is monitored in real time through the third pressure sensor 1053, and the pressure inside the heat treatment furnace 101 is maintained between -16KPa and -13KPa.

[0128] When the temperature inside the heat treatment furnace 101 drops to the set temperature for starting the cooling fan 118, and the pressure inside the heat treatment furnace 101 is lower than -16KPa, the cooling fan 118 is started after a one-minute delay until the temperature inside the heat treatment furnace 101 drops to the preset cooling temperature.

[0129] When the pressure inside the heat treatment furnace 101 is higher than -13KP during the cooling treatment stage, the mass flow controller 1112 is closed. When the pressure inside the heat treatment furnace 101 is higher than -9kPa during the cooling treatment stage, an alarm prompt is issued. When the cooling water temperature in the heat dissipation fins 119 exceeds the preset temperature (such as, exceeding 70°C), the cooling fan 118 is stopped and an alarm prompt is issued. The above set temperatures can all be preset by the operator in the touch screen parameter setting interface. Exemplarily, the heat treatment furnace 101 can be provided with an audible and visual alarm 1014, and this alarm prompt can be issued by the audible and visual alarm 1014.

[0130] In summary, the embodiment of the present application provides a degreasing and sintering method, which can evacuate the interior of the inner furnace 1012 and the heating gap x1 in the furnace shell 1011 through at least one of the first air extraction path 102 and the second air extraction path 103. In the degreasing and sintering process, the first air extraction path 102 or the second air extraction path 103 can be used alone, or the first air extraction path 102 and the second air extraction path 103 can be used simultaneously, which can improve the process flexibility of the degreasing and sintering vacuum system.

[0131] Exemplarily, if the material 30 can release combustible gas during sintering, the first air extraction path 102 can timely extract the combustible gas, and the second air extraction path 103 can prevent the combustible gas from accumulating in the heating gap x1, which can reduce the risk of explosion of the heat treatment furnace 101 and improve the safety of the degreasing and sintering vacuum system. In addition, the interior of the inner furnace 1012 and the heating gap x1 in the furnace shell 1011 can be evacuated through the first air extraction path 102 and the second air extraction path 103 respectively. The double vacuum state can form a double heat insulation barrier. That is, by evacuating the interior of the inner furnace 1012, the gas convection and heat conduction in the heat-insulated inner box can be reduced, and the heat loss on the material 30 can be reduced; by evacuating the heating gap x1, the heat radiation and conduction paths to the outside of the furnace shell 1011 can be further blocked, which can improve the temperature uniformity inside the heat treatment furnace 101.

[0132] It should be noted that in the drawings, the dimensions of the regions may be exaggerated for clarity of illustration. In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, and the indirect coupling or communication connection of the devices or units may be in an electrical, mechanical or other form.

[0133] In the present application, the terms "first", "second", "third", "fourth", "fifth", "sixth", "seventh" and "eighth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. The term "plurality" means two or more, unless otherwise clearly defined.

[0134] Those of ordinary skill in the art can understand that all or part of the steps to implement the above embodiments can be completed by hardware, or can be completed by instructing relevant hardware through a program. The program can be stored in a computer-readable storage medium. The storage medium mentioned above can be a read-only memory, a magnetic disk, an optical disc, etc.

[0135] The above are only alternative embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included within the protection scope of the present application.

Claims

1. A degreasing and sintering vacuum system, characterized in that, Comprising: A heat treatment furnace, a first air extraction path, a second air extraction path, an air extraction pump assembly, and a pressure detection assembly; The heat treatment furnace includes a furnace shell and a heating inner box. The heating inner box is located inside the furnace shell and has a heating gap therebetween. The heating inner box is capable of permeating gas; The intake end of the first air extraction path is communicated with the heating gap, and the outlet end of the first air extraction path is communicated with the air extraction pump assembly; The intake end of the second air extraction path is communicated with the interior of the heating inner box, and the outlet end of the second air extraction path is communicated with the air extraction pump assembly; The pressure detection assembly is used to detect the internal pressure of the furnace shell and the internal pressure of the heating inner box.

2. The degreasing sintering vacuum system according to claim 1, wherein, The intake end of the first air extraction path is communicated with the heating gap from the top of the heat treatment furnace, and the intake end of the second air extraction path is communicated with the interior of the inner furnace from the lower part of the heat treatment furnace; The material of the inner furnace includes graphite.

3. The degreasing sintering vacuum system according to claim 1, wherein The first air extraction path includes a first pipeline and a first valve. The intake port of the first pipeline is located between the furnace shell and the inner furnace, the outlet port of the first pipeline is communicated with the air extraction pump assembly, and the first valve is installed on the first pipeline; The second air extraction path includes a second pipeline and a second valve. The intake port of the second pipeline is located inside the inner furnace, the outlet port of the second pipeline is communicated with the air extraction pump assembly, and the second valve is installed on the second pipeline; The air extraction pump assembly includes a roots pump and a rotary vane pump connected in series. One end of the roots pump is communicated with the outlet ports of the first pipeline and the second pipeline, and the other end of the roots pump is communicated with the rotary vane pump.

4. The degreasing sintering vacuum system according to claim 3, wherein The degreasing and sintering vacuum system further includes: a first communication air path and a first regulating air path connected in parallel; The intake ends of the first communication air path and the first regulating air path are both communicated with the outlet ports of the first pipeline and the second pipeline, and the outlet ends of the first communication air path and the first regulating air path are both communicated with the roots pump; The first regulating air path is used to regulate the gas flow rates of the first pipeline and the second pipeline.

5. The degreasing sintering vacuum system according to claim 4, characterized in that, The first communication air path includes a third pipeline and a third valve. The intake port of the third pipeline is communicated with the outlet ports of the first pipeline and the second pipeline, the outlet port of the third pipeline is communicated with the roots pump, and the third valve is installed on the third pipeline; The first regulating air path includes a fourth pipeline, a fourth valve, and a proportional valve. The intake port of the fourth pipeline is communicated with the outlet ports of the first pipeline and the second pipeline, the outlet port of the fourth pipeline is communicated with the roots pump, and the fourth valve and the proportional valve are installed in parallel on the fourth pipeline.

6. The degreasing sintering vacuum system according to claim 3, characterized in that, The degreasing and sintering vacuum system further includes: a gas storage tank, an inflation air path, a second communication air path and a second regulating air path connected in parallel; The gas storage tank is used to store inert gas; The intake end of the second communication air path and the intake end of the second regulating air path are both connected to the air storage tank. The outlet end of the second communication air path and the outlet end of the second regulating air path are both connected to the inner furnace through the inflation air path. The second regulating air path is used to regulate the gas flow rate of the inflation air path.

7. The degreasing sintering vacuum system according to claim 6, wherein, The inflation air path includes a fifth pipeline and a fifth valve. The outlet of the fifth pipeline is connected to the inner furnace, and the fifth valve is installed on the fifth pipeline. The second communication air path includes a sixth pipeline and a sixth valve. The intake of the sixth pipeline is connected to the air storage tank, the outlet of the sixth pipeline is connected to the intake of the fifth pipeline, and the sixth valve is installed on the sixth pipeline. The second regulating air path includes a seventh pipeline and a mass flow controller. The intake of the seventh pipeline is connected to the air storage tank, the outlet of the seventh pipeline is connected to the intake of the fifth pipeline, and the mass flow controller is installed on the seventh pipeline.

8. The degreasing sintering vacuum system according to claim 3, characterized in that, The degreasing and sintering vacuum system further includes: an intake pipeline, a seventh valve, a wax collecting cylinder, an outlet pipeline, an eighth valve, and a mold temperature controller. Both ends of the intake pipeline are respectively connected to the inner furnace and the wax collecting cylinder, and the seventh valve is installed on the intake pipeline. Both ends of the outlet pipeline are respectively connected to the wax collecting cylinder and the rotary vane pump, and the eighth valve is installed on the outlet pipeline. The mold temperature controller is connected to the wax collecting cylinder.

9. The degreasing sintering vacuum system according to claim 1, wherein, The heat treatment furnace further includes: a heating element. The degreasing and sintering vacuum system further includes: a heat dissipation fan, heat dissipation fins, and a cooling water path. The heating element is located in the heating gap. The heat dissipation fan is located inside the furnace shell and at one end of the inner furnace. The heat dissipation fins are located between the heat dissipation fan and the inner furnace. The cooling water path is connected to the heat dissipation fins.

10. A degreasing and sintering method, characterized in that, The method is used for the degreasing and sintering vacuum system according to any one of claims 1 to 9, and the method includes: Opening the first air extraction path to perform vacuum pumping on the interior of the heat treatment furnace. Performing a vacuum test on the heat treatment furnace through a pressure detection component. Turning on the heating element in the heat treatment furnace to heat the material, and turning on at least one of the first air extraction path and the second air extraction path to perform vacuum sintering on the material. Turning off the heating element and the at least one air path in the heat treatment furnace.

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