Vacuum sintering furnace capable of discharging coke uniformly and easy to clean

Abstract

The invention belongs to the technical field of vacuum furnaces, and particularly relates to a vacuum sintering furnace uniform in coke discharge and easy to clean, which comprises a furnace body, a nitrogen heating shunt box is arranged at a furnace door of the furnace body, and nitrogen introduced from the furnace door is heated and uniformly discharged into the furnace body; a carbon felt, a graphite plate and a heating body group are sequentially arranged on the inner side of the furnace body, the heating body group is connected with an external power supply through a power connection device, and the power connection device is used for electrifying and heating the heating body group and adjusting the position of the heating body group according to the filling amount of nitrogen; a coke discharging device is arranged in the middle of the furnace body, and coke gas generated by heating in the furnace body bursts through a sealing device of a coke discharging pipeline in the furnace of the coke discharging device and is discharged from an external coke discharging pipeline through a check valve; the invention solves the problems of non-uniform distribution of injected nitrogen in the furnace chamber, cold impact of injected normal-temperature nitrogen on local workpieces at the furnace door, incomplete coke discharge, low efficiency, difficult maintenance and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of vacuum furnaces, and in particular relates to a vacuum sintering furnace which is uniform in coke removal and easy to clean. Background Art

[0002] Vacuum furnaces are widely used in metal heat treatment, ceramic sintering, brazing and other fields because of their non-oxidizing working environment, uniform temperature and high controllability.

[0003] During the sintering process of silicon carbide workpieces in a vacuum furnace, a large amount of coke gas will be generated due to chemical reactions. During the heating process, a large amount of protective gas nitrogen must be flushed into the furnace door to quickly clean up the volatile gaseous coke. Existing vacuum furnaces have problems such as uneven distribution of the injected nitrogen in the furnace cavity, cold shock to local workpieces at the furnace door caused by the injected nitrogen at room temperature, incomplete coke removal and low efficiency, and difficult maintenance, which seriously affect the quality and production efficiency of the products. Therefore, it is urgent to design a new type of vacuum sintering furnace to improve the coke removal efficiency, workpiece sintering quality, and the sealing, universality and adjustability of the furnace structure, reduce maintenance costs, and meet the requirements of modern production. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention proposes a vacuum sintering furnace with uniform coke removal and easy cleaning, which solves the problems of uneven distribution of injected nitrogen in the furnace chamber, cold shock of injected nitrogen at normal temperature on local workpieces at the furnace door, incomplete coke removal and low efficiency, and difficult maintenance.

[0005] A vacuum sintering furnace with uniform coke discharge and easy cleaning comprises a furnace body, wherein a nitrogen heating shunt box is arranged at a furnace door of the furnace body, the nitrogen heating shunt box is connected to an external power supply, and the nitrogen introduced at the furnace door is heated and uniformly discharged into the furnace body; a carbon felt, a graphite plate and a heating body group are arranged in sequence on the inner side of the furnace body, and the heating body group is connected to an external power supply through an electric connection device, and the electric connection device is used for energizing and heating the heating body group and adjusting the position of the heating body group according to the nitrogen charging amount; a coke discharge device is arranged at the middle part of the furnace body, and a detachable sealing device is arranged at an inner coke discharge port of an inner coke discharge pipe of the coke discharge device, and a check valve is arranged at the outer side of an outer coke discharge port of the inner coke discharge pipe, and only nitrogen in the furnace can pass through the check valve, and the outer coke discharge port of the inner coke discharge pipe of the furnace is connected to an external coke discharge pipe through a flange plate through the check valve, and the coke gas generated by heating in the furnace body breaks the sealing device of the inner coke discharge pipe and is discharged from the external coke discharge pipe through the check valve.

[0006] The nitrogen heating diverter box comprises a nitrogen inlet graphite collecting plate, a honeycomb carbon-carbon composite material heating plate, and a nitrogen outlet carbon-carbon dispersion plate. The nitrogen inlet graphite collecting plate, the honeycomb carbon-carbon composite material heating plate, and the nitrogen outlet carbon-carbon dispersion plate are sequentially arranged from the outside to the inside of the furnace door. The top of the honeycomb carbon-carbon composite material heating plate is provided with an electrical port for connecting an external power supply; four inflation holes are arranged on the nitrogen inlet graphite collecting plate, and external nitrogen is gathered into the furnace body through the inflation holes, and the honeycomb carbon-carbon composite material heating plate heats and disperses the nitrogen that rushes in; the dispersion holes of the nitrogen outlet carbon-carbon dispersion plate and the honeycomb holes of the honeycomb carbon-carbon composite material heating plate are staggered to evenly disperse the dispersed nitrogen into the furnace body.

[0007] The coke discharge port of the coke discharge pipe in the furnace is a trumpet-shaped structure, which is used to expand the output of coke gas; the sealing device is embedded in the coke discharge port in the furnace, and the sealing device includes a trumpet-shaped silicon carbide ceramic and a single-end fixed molybdenum sheet. A connecting rod is provided at the bottom of the trumpet-shaped silicon carbide ceramic, one end of the connecting shaft is clamped on the connecting rod, and the other end is fixedly connected to the single-end fixed molybdenum sheet. The coke gas discharged from the furnace acts on the single-end fixed molybdenum sheet, and the single-end fixed molybdenum sheet rotates on the connecting rod through the connecting shaft, and the single-end fixed molybdenum sheet is opened, and the coke gas passes through.

[0008] The check valve includes a fixed plate, which has a circular structure. Four molybdenum sheets are arranged on the fixed plate, of which two molybdenum sheets I are semicircular arc structures and are arranged on the left and right sides of the fixed plate with a gap in the middle. The other two molybdenum sheets II are fixed to the upper and lower sides of the fixed plate through a fixed shaft, located on the rear side of the molybdenum sheet I, and fill the gap between the molybdenum sheets I with partial overlap; a handle is provided on the top of the fixed plate to facilitate insertion and removal.

[0009] The heating body group includes multiple groups of heating bodies, and the heating bodies include graphite heating tubes, left-side powered plates, right-side powered plates and connecting components. The graphite heating tubes are slidably connected to the left-side powered plates, right-side powered plates and graphite heating tube power connection plates. At the same time, the graphite heating tubes are detachably connected to the left-side powered plates, right-side powered plates and graphite heating tube power connection plates through the connecting components. The graphite heating tube power connection plates are electrically connected to the graphite heating tubes. The graphite heating tube power connection plates are used to energize the graphite heating tubes. The graphite heating tubes are used to energize and generate heat and conduct electrical energy to the left-side powered plates, so that the electrical energy is conducted to other graphite heating tubes through the left-side powered plates and the right-side pass-band plates.

[0010] The power connection device includes an electrode, an electrode power-on plate, a power-on bolt, and a graphite heating tube power-on plate. One end of the electrode power-on plate is connected to the electrode, which is connected to an external power source, and the other end is connected to the power-on bolt. The power-on nut fixes the graphite heating tube power-on plate on the power-on bolt. The graphite heating tube power-on plate is connected to the graphite heating tube of the heating body group. The external power source supplies power to the graphite heating tube power-on plate through the electrode, the power-on bolt, and the power-on nut. Furthermore, a slide groove is provided on the electrode power-on plate, and the power-on bolt drives the graphite heating tube power-on plate to move on the electrode power-on plate.

[0011] The left-side power-carrying plate includes four corner porous power-carrying plates and two first porous power-carrying straight plates, the first porous power-carrying straight plates are arranged between the corner porous power-carrying plates, and the four corner porous power-carrying plates and the two first porous power-carrying straight plates are combined to form a first square shape; the corner porous power-carrying plate is provided with a first slot, and the shape of the first slot is adapted to the shape of the corner porous power-carrying plate; the first porous power-carrying straight plate is provided with a second slot, and the shape of the second slot is adapted to the shape of the first porous power-carrying straight plate, and the first slot and the second slot are used to accommodate the port of the graphite heating tube.

[0012] The right-side power-carrying plate includes three second porous power-carrying straight plates, three graphite heating tube power-carrying plates and three second porous power-carrying straight plates are alternately spliced ​​to form a second square shape, and the area of ​​the first square shape is the same as that of the second square shape; the second porous power-carrying straight plate is provided with a third slot, and the shape of the third slot is adapted to the shape of the second porous power-carrying straight plate; the graphite heating tube power-carrying plate is provided with a fourth slot, and the shape of the fourth slot is adapted to the shape of the graphite heating tube power-carrying plate; the third slot and the fourth slot are used to accommodate the ports of the graphite heating tube.

[0013] Threaded interfaces are provided at both ends of the graphite heating tube; the connecting assembly includes graphite heating tube port fixing nuts and bolts, and multiple groups of bolt fixing reserved openings are provided on both sides of the first slot, the second slot, the third slot and the fourth slot. The two ends of the graphite heating tube are threadedly positioned by the graphite heating tube port fixing nuts, and the graphite heating tube port fixing nuts are fixed in the bolt fixing reserved openings by bolts, so that the graphite heating tube is fixed in the corner multi-porous power-carrying plate, the first multi-porous power-carrying straight plate, the second multi-porous power-carrying straight plate and the graphite heating tube power connection plate.

[0014] The beneficial effects of the present invention are:

[0015] 1. A nitrogen heating diverter box is provided at the furnace door of the present application, which effectively solves the problems of cold impact of room temperature nitrogen on part of the workpiece at the furnace door during heat treatment, uneven distribution of the injected nitrogen in the furnace cavity, limited nitrogen filling rate and uneven temperature at the furnace door.

[0016] 2. The trumpet-shaped structure of the coke discharge port in the furnace can increase the size of the coke discharge port and the rate of coke discharge. The assembly of the openable and closable single-end fixed molybdenum sheet and trumpet-shaped silicon carbide ceramic with the coke discharge port in the detachable sealing device can improve the sealing and radiation capacity of the furnace chamber, and facilitate the maintenance, replacement and cleaning of the coke discharge port. The check valve can solve the problem of reflux of coke gas discharged after coke discharge, and facilitates the maintenance, replacement and cleaning of the coke discharge pipe outside the furnace body.

[0017] 3. The position of the heating body is adjusted through the power connection device, which effectively solves the influence of the adjustment of the nitrogen injection rate on the temperature uniformity of the furnace body.

[0018] 4. In the adjustable graphite heating device for the vacuum furnace of the present application, the graphite heating tube can be slidably adjusted on the left-side powered plate and the right-side powered plate according to the heating demand. After the position of the graphite heating tube is determined, the connection of the graphite heating tube is completed through the connecting assembly, thereby improving the stability of power connection and the convenience of installation and disassembly.

[0019] 5. It effectively solves the problem that when the graphite heating tube is damaged during heat treatment and reaches the end of its service life and needs to be replaced, the entire heating system needs to be disassembled before replacement. The position and quantity of the graphite heating tube can be adjusted according to different heating requirements, thereby improving the adaptability and flexibility of the equipment, improving the temperature uniformity and heating efficiency of the heated workpiece during heat treatment, and saving energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a front view of the vacuum furnace of the present invention;

[0021] Figure 2 A top view of the vacuum furnace of the present invention;

[0022] Figure 3 It is a structural schematic diagram of a nitrogen heating manifold box of a vacuum furnace of the present invention;

[0023] Figure 4 A schematic diagram of the structure of a vacuum furnace door equipped with a nitrogen heating shunt box;

[0024] Figure 5 It is a structural schematic diagram of a coke removal device of a vacuum furnace of the present invention;

[0025] Figure 6 It is a structural schematic diagram of the sealing device of the vacuum furnace of the present invention;

[0026] Figure 7 It is a structural schematic diagram of a check valve of a vacuum furnace of the present invention;

[0027] Figure 8 It is a structural schematic diagram of a fixing method of the molybdenum sheet II of the check valve of the vacuum furnace of the present invention;

[0028] Fig. 9 It is a schematic diagram of the position relationship between the molybdenum sheet I and the molybdenum sheet II of the check valve of the vacuum furnace of the present invention;

[0029] Fig.10 It is a structural schematic diagram of the power connection device of the vacuum furnace of the present invention;

[0030] Fig.11 It is a schematic diagram of the structure of the connection between the electrode power supply plate and the electrode of the vacuum furnace of the present invention;

[0031] Fig.12 It is a structural schematic diagram of the power connection bolts and power connection nuts of the vacuum furnace of the present invention;

[0032] Fig.13 It is a structural schematic diagram of the heating body of the vacuum furnace of the present invention;

[0033] Fig.14 It is a schematic diagram of the connection between the heating body and the power supply device of the vacuum furnace of the present invention;

[0034] Fig.15 It is a structural schematic diagram of a fixing nut of a vacuum furnace of the present invention;

[0035] Fig.16 It is an enlarged view of the connection between the graphite heating tube connecting plate and the graphite heating tube of the vacuum furnace of the present invention;

[0036] In the attached drawings: 1. furnace body; 2. carbon felt; 3. graphite plate; 4. heating body; 401. graphite heating tube; 402. corner multi-hole power plate; 403. first multi-hole power straight plate; 404. second multi-hole power straight plate; 405. graphite heating tube port fixing nut; 406. bolt; 407. bolt fixing reserved opening; 5. nitrogen heating manifold box; 501. nitrogen inlet graphite collecting plate; 5011. charging hole; 502. honeycomb carbon-carbon composite material heating plate; 5021. power connection port; 503. nitrogen outlet carbon-carbon dispersion plate; 6. power connection device; 601. electrode ; 602, electrode power plate; 603, power bolt; 604, graphite heating tube power plate; 605, power nut; 7, coke discharge device; 701, coke discharge pipe in the furnace; 702, coke discharge port in the furnace; 703, sealing device; 7031, trumpet-shaped silicon carbide ceramic; 7032, single-end fixed molybdenum sheet; 7033, connecting rod; 7034, connecting shaft; 704, coke discharge port outside the furnace; 705, check valve; 7051, fixing plate; 7052, molybdenum sheet I; 7053, handle; 7054, fixed shaft; 7055, molybdenum sheet II; 706, external coke discharge pipe. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0038] like Figures 1 to 16 As shown, a vacuum sintering furnace with uniform coke discharge and easy cleaning comprises a furnace body 1, a furnace door of the furnace body 1 is provided with a nitrogen heating shunt box 5, the nitrogen heating shunt box 5 is connected to an external power supply, and the nitrogen introduced at the furnace door is heated and uniformly discharged into the furnace body 1; the nitrogen heating shunt box 5 comprises a nitrogen inlet graphite collecting plate 501, a honeycomb carbon-carbon composite material heating plate 502, and a nitrogen outlet carbon-carbon dispersion plate 503, and the nitrogen inlet graphite collecting plate 501, the honeycomb carbon-carbon composite material heating plate 502, and the nitrogen outlet carbon-carbon dispersion plate 503 are arranged in sequence from the outside to the inside of the furnace door, and the top of the honeycomb carbon-carbon composite material heating plate 502 is provided with an electrical port 5021 for connecting External power supply; 4 inflation holes 5011 are arranged on the nitrogen inlet graphite collecting plate 501, and the external nitrogen is gathered into the furnace body 1 through the inflation holes 5011, and the honeycomb carbon-carbon composite material heating plate 502 heats and disperses the nitrogen rushing in, so as to alleviate the direct cold impact of cold air on some workpieces at the furnace door. The power of the honeycomb carbon-carbon composite material heating plate 502 can be adjusted according to the nitrogen rushing rate, so as to balance the temperature in the furnace; the dispersion holes of the nitrogen outlet carbon-carbon dispersion plate 503 and the honeycomb holes of the honeycomb carbon-carbon composite material heating plate 502 are staggered, so as to evenly disperse the dispersed nitrogen into the furnace body 1, and solve the problem of uneven distribution of the rushing nitrogen in the furnace cavity;

[0039] The inner side of the furnace body 1 is provided with a carbon felt 2, a graphite plate 3, and a heating body group in sequence. The heating body group is connected to an external power source through a power connection device 6. The power connection device 6 is used for heating the heating body group by electricity and adjusting the position of the heating body group according to the amount of nitrogen charged.

[0040] At present, the structural design of the graphite heating tube of the vacuum furnace is fixed in the furnace body by tightening bolts and nuts. When the graphite heating tube is damaged or expires and needs to be replaced, the heating system of the entire vacuum furnace needs to be disassembled before replacement. This replacement not only has a large workload, but also may cause damage to the intact graphite heating tube during disassembly; and the spacing, position and number between the existing graphite heating tubes are not easy to change, which leads to uneven temperature and low heating efficiency in the vacuum furnace during heat treatment. The adaptability and flexibility are poor and cannot meet the requirements of modern production. At the same time, due to the different workpieces to be processed, mutual interference may occur between a single group of heating bodies.

[0041] The heating body group setting of the present application effectively solves the problem that when the graphite heating tube is damaged during heat treatment and needs to be replaced after reaching the end of its service life, the entire heating system needs to be disassembled for replacement. The position and number of the graphite heating tube can be adjusted according to different heating requirements, thereby improving the adaptability and flexibility of the equipment, improving the temperature uniformity and heating efficiency of the heated workpiece during heat treatment, saving energy, and avoiding interference between processed workpieces by setting up multiple groups of heating bodies. At the same time, the position of the heating body group can be adjusted according to changes in the heating temperature at the furnace door.

[0042] In the present application, the heating body group includes multiple groups of heating bodies 4, and in this embodiment, there are three groups of heating bodies 4. The heating body 4 includes a graphite heating tube 401, a left-side power-on plate, a right-side power-on plate, and a connecting assembly. The graphite heating tube 401 is slidably connected to the left-side power-on plate, the right-side power-on plate, and the graphite heating tube power-on plate 604. At the same time, the graphite heating tube 401 is detachably connected to the left-side power-on plate, the right-side power-on plate, and the graphite heating tube power-on plate 604 through the connecting assembly. The graphite heating tube power-on plate 604 is electrically connected to the graphite heating tube 401. The graphite heating tube power-on plate 604 is used to energize the graphite heating tube 401. The graphite heating tube 401 is used to energize and generate heat and conduct electrical energy to the left-side power-on plate, so that the electrical energy is conducted to other graphite heating tubes 401 through the left-side power-on plate and the right-side passband plate; the power connection device 6 It includes an electrode 601, an electrode power-on plate 602, a power-on bolt 603, and a graphite heating tube power-on plate 604. One end of the electrode power-on plate 602 is connected to the electrode 601, the electrode 601 is connected to an external power source, and the other end is connected to the power-on bolt 603. The power-on nut 605 fixes the graphite heating tube power-on plate 604 on the power-on bolt 603. The graphite heating tube power-on plate 604 is connected to the graphite heating tube 401 of the heating body group. The external power source supplies power to the graphite heating tube power-on plate 604 through the electrode 601, the power-on bolt 603, and the power-on nut 605. Furthermore, a slide groove is provided on the electrode power-on plate 602, and the power-on bolt 603 drives the graphite heating tube power-on plate 604 to move on the electrode power-on plate 602 to adjust the position of the heating component, and a screw is used to fix the graphite heating tube power-on plate 604 to the electrode power-on plate 602.

[0043] In this embodiment, the graphite heating tube 401 is the core heating element in the vacuum furnace. The working temperature of the graphite heating tube 401 is between 80 and 2000 degrees Celsius. It converts electrical energy into thermal energy through the principle of resistance heating. It is made of high-purity graphite material, has excellent high temperature resistance and good electrical conductivity, and can directly heat the material in the furnace to provide the required temperature environment.

[0044] The left-side powered plate and the right-side powered plate are respectively located at the two ends of the graphite heating tube 401. They serve as channels for current transmission and support structures of the graphite heating tube 401. They are made of highly conductive and high-temperature resistant graphite materials, providing a stable power supply for the graphite heating tube; and can ensure that the graphite heating tube maintains a stable position and shape during the heating process to prevent damage caused by thermal expansion or vibration.

[0045] The power connection device 6 is a part that connects the external power source with the graphite heating tube 401 , and is usually made of highly conductive graphite, and is used to introduce the external power source into the graphite heating tube 401 for heating.

[0046] The connecting assembly is used to detachably mount the graphite heating tube 401 on the left-side powered plate and the right-side powered plate, ensuring good electrical contact and mechanical connection between the graphite heating tube 401 and the powered plate; and allowing the operator to adjust the position and quantity of the graphite heating tube 401 as needed to adapt to the heating requirements of materials of different sizes and shapes; and when the graphite heating tube 401 is damaged or needs to be replaced, it can be easily disassembled and installed to reduce maintenance costs and time.

[0047] The middle part of the furnace body 1 is provided with a coke discharge device 7, and the coke discharge port 702 of the coke discharge pipe 701 of the coke discharge device 7 is provided with a detachable sealing device 703, and the outer coke discharge port 704 of the coke discharge pipe 701 is provided with a non-return valve 705, and only nitrogen in the furnace can pass through the non-return valve 705. The coke discharge port 704 of the coke discharge pipe 701 in the furnace is connected to the external coke discharge pipe 706 through the non-return valve 705 through the flange, and the coke gas generated by heating in the furnace body 1 breaks the sealing device 703 of the coke discharge pipe 701 in the furnace and is discharged from the external coke discharge pipe 706 through the non-return valve 705; the coke discharge port 704 of the coke discharge pipe 701 in the furnace is provided with a non-return valve 705, and the coke discharge port 704 of the coke discharge pipe 701 in the furnace is connected to the external coke discharge pipe 706 through the non-return valve 705; 702 is a trumpet-shaped structure, which is used to expand the output of coke gas; the sealing device 703 is embedded in the coke discharge port 702 in the furnace, and the sealing device 703 includes a trumpet-shaped silicon carbide ceramic 7031 and a single-end fixed molybdenum sheet 7032. A connecting rod 7033 is provided at the bottom of the trumpet-shaped silicon carbide ceramic 7031. One end of the connecting shaft 7034 is clamped on the connecting rod 7033, and the other end is fixedly connected to the single-end fixed molybdenum sheet 7032. The coke gas discharged from the furnace acts on the single-end fixed molybdenum sheet 7032, and the single-end fixed molybdenum sheet 7032 rotates on the connecting rod 7033 through the connecting shaft 7034, and the single-end fixed molybdenum sheet 7032 is opened, and the coke gas passes through;

[0048] The check valve 705 includes a fixed plate 7051, which is a circular structure. Four molybdenum sheets are arranged on the fixed plate 7051, of which two molybdenum sheets I 7052 are semicircular structures and are arranged on the left and right sides of the fixed plate 7051 with a gap in the middle. The other two molybdenum sheets II 7055 are fixed to the upper and lower sides of the fixed plate 7051 through a fixed shaft 7054, located on the rear side of the molybdenum sheet I 7052, and fill the gap between the molybdenum sheets I 7052 and partially overlap. The check valve 705 only allows the coke gas in the furnace to pass through. When discharging coke, the molybdenum sheet II 7055 is opened to allow the coke gas to pass through, and the discharged coke gas cannot return to the furnace body 1 from the molybdenum sheet II 7055. A handle 7053 is provided on the top of the fixed plate 7051 to facilitate insertion and removal.

[0049] The trumpet-shaped structural design of the coke discharge port 702 in the furnace can increase the size of the coke discharge port and the coke discharge rate. The assembly of the openable and closable single-end fixed molybdenum sheet 7032 and the trumpet-shaped silicon carbide ceramic with the coke discharge port in the detachable sealing device 703 can improve the sealing and radiation capacity of the furnace chamber, and facilitate the maintenance, replacement and cleaning of the coke discharge port. The check valve 705 can solve the problem of backflow of coke gas discharged after coke discharge is completed, and facilitates the maintenance, replacement and cleaning of the coke discharge pipe outside the furnace body.

[0050] In this embodiment, the left side power-carrying plate includes four corner porous power-carrying plates 402 and two first porous power-carrying straight plates 403, and the first porous power-carrying straight plates 403 are arranged between the corner porous power-carrying plates 402. The four corner porous power-carrying plates 402 and the two first porous power-carrying straight plates 403 are combined to form a first square shape; specifically, the left side power-carrying plate serves as a component for supporting one end of the graphite heating tube 401 and transmitting current. The left side power-carrying plate includes four corner porous power-carrying plates 402 and two first porous power-carrying straight plates 403, wherein the four corner porous power-carrying plates 402 are respectively located at the four corners of the first square shape, playing a role in supporting and fixing the entire structure, and the two first porous power-carrying straight plates 403 ... and the four corner porous power-carrying plates 402 are respectively located at the four corners of the first square shape, playing a role in supporting and fixing the entire structure, and the two first porous power-carrying straight plates The electric straight plates 403 are arranged in parallel and are located between the four corner multi-porous electric plates 402, and together with the corner multi-porous electric plates 402, they form a complete first square shape; the left electric plate serves as a supporting structure at one end of the graphite heating tube 401, and can withstand the thermal stress and mechanical stress generated by the graphite heating tube at high temperature, ensuring the stability and safety of the graphite heating tube 401 during the heating process; one end of the graphite heating tube 401 is detachably mounted on the corner multi-porous electric plate 402 and the first multi-porous electric straight plate 403 through the connecting assembly, and the graphite heating tubes 401 on the corner multi-porous electric plate 402 and the first multi-porous electric straight plate 403 are arranged at equal intervals;

[0051] In the embodiment of the present application, the connecting assembly is used to connect the graphite heating tube 401 with the corner porous power-carrying plate 402 and the first porous power-carrying straight plate 403, so that the graphite heating tube 401 can be firmly installed on the corner porous power-carrying plate 402 and the first porous power-carrying straight plate 403, and ensure that the current can pass smoothly; the detachable design makes it possible to conveniently remove or reinstall the graphite heating tube 401 from the corner porous power-carrying plate 402 and the first porous power-carrying straight plate 403 at an angle when necessary, so as to facilitate maintenance, replacement or adjustment of the position of the graphite heating tube 401.

[0052] On the corner multi-hole conductive plate 402 and the first multi-hole conductive straight plate 403, the spacing between the graphite heating tubes 01 is equal, which means that the distance between each graphite heating tube 401 and its adjacent graphite heating tube 401 is consistent. The equal spacing setting helps to achieve uniform distribution of temperature in the furnace. Since the distance between the graphite heating tubes 401 is equal, the heating effect of each graphite heating tube 401 on the material in the furnace is also similar, thereby avoiding material quality problems caused by uneven heating. And the equal spacing setting also helps to optimize the heat conduction efficiency, thereby improving the heating efficiency of the entire furnace body.

[0053] The right-side powered plate includes three second porous powered straight plates 404, three graphite heating tube power plates 604 and three second porous powered straight plates 404 are alternately spliced ​​to form a second square shape, and the first square shape and the second square shape have the same area size; in the embodiment of the present application, the second porous powered straight plates 404 and the graphite heating tube power plates 604 are both designed as porous structures, and the second square shape and the first square shape are the same in area size, that is, the powered plates on the left and right sides are consistent in geometric dimensions, and the symmetrical design helps to ensure uniform distribution of heat during heating and reduce the problem of uneven heating caused by structural asymmetry.

[0054] The right side powered plate forms a stable square structure, which not only enhances the stability of the right side powered plate itself, but also helps to improve the heating stability of the entire vacuum furnace;

[0055] The other ends of the graphite heating tubes 401 are detachably mounted on the second multi-hole straight plate 404 and the graphite heating tube connection plate 604 through a connecting assembly, and the graphite heating tubes 401 on the second multi-hole straight plate 404 and the graphite heating tube connection plate 604 are arranged at equal intervals;

[0056] The other end of the graphite heating tube 401 is detachably connected to the second multi-hole electrified straight plate 404 and the graphite heating tube electrical connection plate 604 through a connecting assembly. The detachable connection method not only ensures close contact and good electrical conductivity between the graphite heating tube 401 and the second multi-hole electrified straight plate 404 and the graphite heating tube electrical connection plate 604, but also enables the graphite heating tube 401 to be easily disassembled from the second multi-hole electrified straight plate 404 by tilting when necessary, which is convenient for maintenance, replacement or position adjustment;

[0057] On the second multi-hole electric straight plate 404 and the graphite heating tube connecting plate 604, the spacing between the graphite heating tubes 401 is equal, that is, the distance between each graphite heating tube 401 and its adjacent graphite heating tube 401 is consistent, thereby ensuring the uniform transfer of heat between the graphite heating tubes 401 and the uniform distribution of the temperature in the furnace. In addition, in a high temperature environment, the graphite heating tube 401 may undergo slight deformation due to thermal expansion and contraction, and the equal spacing setting can alleviate the influence of such deformation on the overall stability of the heating system to a certain extent.

[0058] The detachable connection assembly makes it easier to maintain and replace the graphite heating tube 401; when the graphite heating tube 401 fails or needs to be cleaned, the operator can quickly remove it from the second porous straight plate 404 and the graphite heating tube power board 604 for processing without disassembling the entire furnace body.

[0059] A first slot is provided on the corner multi-porous conductive plate 402, and the shape of the first slot matches the shape of the corner multi-porous conductive plate 402. A second slot is provided on the first multi-porous conductive straight plate 403, and the shape of the second slot matches the shape of the first multi-porous conductive straight plate 403. The first slot and the second slot are used to accommodate the port of the graphite heating tube 401, and the port portion thereof will be embedded in the corresponding slot, and a stable connection between the graphite heating tube 401 and the graphite heating tube conductive plate 604 is realized through the graphite heating tube port fixing nut 405 and bolt 406;

[0060] A third slot is provided on the second multi-porous straight plate 404, and the shape of the third slot is adapted to the shape of the second multi-porous straight plate 404. A fourth slot is provided on the graphite heating tube power connection plate 604, and the fourth slot is divided into two parts, and the shape of the fourth slot is adapted to the shape of the graphite heating tube power connection plate 604. The third slot and the fourth slot are used to accommodate the port of the graphite heating tube 401. When the graphite heating tube 401 is installed on the second multi-porous straight plate 404 and the graphite heating tube power connection plate 604, its port part will be embedded in the third slot and the fourth slot, and the graphite heating tube port fixing nut 405 and bolt 406 are used to realize the stable connection between the graphite heating tube 401 and the second multi-porous straight plate 404 and the graphite heating tube power connection plate 604.

[0061] The two ends of the graphite heating tube 401 are provided with threaded interfaces, so that the graphite heating tube 401 can be closely matched with the graphite heating tube port fixing nut 405 through threaded connection, so as to achieve positioning; the connection component includes the graphite heating tube port fixing nut 405 and the bolt 406, and the first slot, the second slot, the third slot and the fourth slot are provided with multiple groups of bolt fixing reserved openings 407 on both sides, and the two ends of the graphite heating tube 401 are threadedly positioned by the graphite heating tube port fixing nut 405, and the graphite heating tube port fixing nut 405 is fixed in the bolt fixing reserved opening 407 by the bolt 406, so that the graphite heating tube 401 is fixed in the corner multi-hole electrified plate 402, the first multi-hole electrified straight plate 403, the second multi-hole electrified straight plate 404 and the graphite heating tube power connection plate 604;

[0062] During installation, first align the port of the graphite heating tube 401 with the corresponding slot and embed it therein, then tighten the graphite heating tube port fixing nut 405 on the threaded interface of the port of the graphite heating tube 401 to perform preliminary thread positioning; finally, use the bolt 406 to pass through the bolt fixing reserved opening 407 to tightly fix the graphite heating tube port fixing nut 405, thereby completing the installation of the graphite heating tube 401.

[0063] Through the dual fixing effects of the graphite heating tube port fixing nut 405 and bolt 406, the graphite heating tube 401 can be firmly installed on the graphite heating tube power board 604. This stable connection not only ensures the stability of the graphite heating tube 401 during the heating process, but also avoids safety accidents caused by loosening or falling off.

[0064] Optionally, a three-phase triangle power connection method is adopted between the graphite heating tube power connection plates 604, and three graphite heating tube power connection plates 604 are arranged between two of the graphite heating tubes 401, and are connected in parallel with the graphite heating tubes 401 in pairs and then in series.

[0065] The three graphite heating tube connection plates 604 are connected by a three-phase triangle connection method, which connects the three phases of the three-phase power supply to the three connection plates respectively to form a closed triangle loop.

[0066] The three graphite heating tube connection plates 604 are not directly connected, but are respectively arranged between two graphite heating tubes 401, and each connection plate is connected to the adjacent graphite heating tube 401 through a wire to form a parallel relationship. Then, these parallel-connected graphite heating tubes 401 are connected in series to the entire circuit system.

[0067] In the present application, the graphite heating tubes 401 are first connected in parallel in pairs, that is, one end of each two graphite heating tubes 401 is connected to a graphite heating tube power board 604, and the other end is connected to another graphite heating tube power board 604. In this way, each two graphite heating tubes 401 form a parallel unit. Then, these parallel units are connected in series to connect the entire circuit system.

[0068] The three-phase triangle connection method can ensure that the three-phase power supply distributes current evenly among the three connection boards, which helps to reduce equipment damage and safety hazards caused by current imbalance. In addition, the graphite heating tubes 401 are connected in parallel and then in series, so that each graphite heating tube 401 can obtain relatively uniform current and voltage. This balanced power distribution helps to improve heating efficiency and make the heating process faster and more stable.

[0069] The working process of the vacuum furnace in this application is as follows:

[0070] First, according to the size of the heated workpiece in the furnace body 1 and the process requirements such as the input amount of external nitrogen, the graphite heating tube connection plate 604 is driven to move on the electrode power plate 602 through the power connection bolt 603, so as to move the heating body 4 as a whole, and adjust the distance between the three groups of heating bodies 4. When the amount of nitrogen introduced at the furnace door is large, the heating body 4 at the furnace door can be moved into the furnace body 1. At the same time, according to the heating temperature and the process requirements of the workpiece, the number and spacing of the graphite heating tubes 401 are adjusted by removing or adjusting the position of the connection components on the left power plate and the right power plate;

[0071] Then a certain amount of nitrogen is introduced, and the nitrogen passes through the nitrogen heating shunt box 5 at the furnace door, and the honeycomb carbon-carbon composite material heating plate 502 provides heat to balance the temperature in the furnace. At the same time, its honeycomb design heats and disperses the nitrogen that rushes in, alleviating the direct cold impact of cold air on some workpieces at the furnace door. The dispersed nitrogen is evenly dispersed into the furnace body 1 through the dispersion holes staggered with the honeycomb holes on the nitrogen outlet carbon-carbon dispersion plate 503;

[0072] Finally, the coke gas generated in the furnace body 1 passes through the trumpet-shaped furnace coke discharge port 702. The trumpet-shaped design increases the output of the coke gas. Nitrogen passes through the single-end fixed molybdenum sheet 7032 of the sealing device 703. The single-end fixed molybdenum sheet 7032 rotates on the connecting rod 7033 through the connecting shaft 7034. The single-end fixed molybdenum sheet 7032 is opened, and the coke gas passes through. Finally, the coke gas is discharged from the external coke discharge pipe 706 through the check valve 705. The check valve 705 prevents external air from entering. The setting of the sealing device 703 improves the sealing and radiation capacity of the furnace chamber. The check valve 705 solves the problem of backflow of the discharged coke gas after the coke discharge is completed.

[0073] The vacuum furnace of the present application can realize the input of a large amount of nitrogen through the nitrogen heating diverter box 5, the setting of the coke removal device 7 and the mobility of the heating body 4, thereby improving the coke removal efficiency, the sintering quality of the workpiece and the sealing, universality and adjustability of the furnace structure, reducing maintenance costs and meeting modern production requirements.

Claims

1. A vacuum sintering furnace with uniform coke removal and easy cleaning, characterized in that: The invention comprises a furnace body, wherein a nitrogen heating shunt box is arranged at the furnace door of the furnace body, the nitrogen heating shunt box is connected to an external power supply, and the nitrogen introduced at the furnace door is heated and uniformly discharged into the furnace body; a carbon felt, a graphite plate and a heating body group are arranged in sequence on the inner side of the furnace body, and the heating body group is connected to an external power supply through an electric connection device, and the electric connection device is used for energizing and heating the heating body group and adjusting the position of the heating body group according to the nitrogen charging amount; a coke discharge device is arranged in the middle of the furnace body, and a detachable sealing device is arranged at the inner coke discharge port of the inner coke discharge pipe of the coke discharge device, and a non-return valve is arranged at the outer side of the outer coke discharge port of the inner coke discharge pipe, and only nitrogen in the furnace can pass through the non-return valve, and the outer coke discharge port of the inner coke discharge pipe of the furnace is connected to the external coke discharge pipe through a flange plate through the non-return valve, and the coke gas generated by heating in the furnace body breaks the sealing device of the inner coke discharge pipe and is discharged from the external coke discharge pipe through the non-return valve.

2. A vacuum sintering furnace with uniform coke removal and easy cleaning according to claim 1, characterized in that: The nitrogen heating shunt box comprises a nitrogen inlet graphite collecting plate, a honeycomb carbon-carbon composite material heating plate, and a nitrogen outlet carbon-carbon dispersion plate. The nitrogen inlet graphite collecting plate, the honeycomb carbon-carbon composite material heating plate, and the nitrogen outlet carbon-carbon dispersion plate are sequentially arranged from the outside to the inside of the furnace door. The top of the honeycomb carbon-carbon composite material heating plate is provided with an electrical port for connecting an external power supply; the nitrogen inlet graphite collecting plate is provided with 4 inflation holes, and the external nitrogen is gathered into the furnace body through the inflation holes, and the honeycomb carbon-carbon composite material heating plate heats and disperses the nitrogen that rushes in; The dispersion holes of the nitrogen outlet carbon-carbon dispersion plate and the honeycomb holes of the honeycomb carbon-carbon composite material heating plate are arranged in a staggered manner, so that the dispersed nitrogen is evenly dispersed into the furnace body.

3. The vacuum sintering furnace with uniform coke removal and easy cleaning according to claim 1, characterized in that: The coke discharge port of the coke discharge pipe in the furnace is a trumpet-shaped structure, which is used to expand the output of coke gas; the sealing device is embedded in the coke discharge port in the furnace, and the sealing device includes a trumpet-shaped silicon carbide ceramic and a single-end fixed molybdenum sheet. A connecting rod is provided at the bottom of the trumpet-shaped silicon carbide ceramic, one end of the connecting shaft is clamped on the connecting rod, and the other end is fixedly connected to the single-end fixed molybdenum sheet. The coke gas discharged from the furnace acts on the single-end fixed molybdenum sheet, and the single-end fixed molybdenum sheet rotates on the connecting rod through the connecting shaft, and the single-end fixed molybdenum sheet is opened, and the coke gas passes through.

4. The vacuum sintering furnace with uniform coke removal and easy cleaning according to claim 1, characterized in that: The check valve includes a fixed plate, which has a circular structure. Four molybdenum sheets are arranged on the fixed plate, of which two molybdenum sheets I are semicircular arc structures and are arranged on the left and right sides of the fixed plate with a gap in the middle. The other two molybdenum sheets II are fixed to the upper and lower sides of the fixed plate through a fixed shaft, located on the rear side of the molybdenum sheet I, and fill the gap between the molybdenum sheets I with partial overlap; a handle is provided on the top of the fixed plate to facilitate insertion and removal.

5. The vacuum sintering furnace with uniform coke removal and easy cleaning according to claim 1, characterized in that: The power connection device includes an electrode, an electrode power-on plate, a power-on bolt, and a graphite heating tube power-on plate. One end of the electrode power-on plate is connected to the electrode, which is connected to an external power source, and the other end is connected to the power-on bolt. The power-on nut fixes the graphite heating tube power-on plate on the power-on bolt. The graphite heating tube power-on plate is connected to the heating body group. The external power source supplies power to the graphite heating tube power-on plate through the electrode, the power-on bolt, and the power-on nut. Furthermore, a slide groove is provided on the electrode power-on plate, and the power-on bolt drives the graphite heating tube power-on plate to move on the electrode power-on plate.

6. A vacuum sintering furnace with uniform coke removal and easy cleaning according to claim 5, characterized in that: The heating body group includes multiple groups of heating bodies, and the heating bodies include graphite heating tubes, left-side powered plates, right-side powered plates and connecting components. The graphite heating tubes are slidably connected to the left-side powered plates, right-side powered plates and graphite heating tube power connection plates. At the same time, the graphite heating tubes are detachably connected to the left-side powered plates, right-side powered plates and graphite heating tube power connection plates through the connecting components. The graphite heating tube power connection plates are electrically connected to the graphite heating tubes. The graphite heating tube power connection plates are used to energize the graphite heating tubes. The graphite heating tubes are used to energize and generate heat and conduct electrical energy to the left-side powered plates, so that the electrical energy is conducted to other graphite heating tubes through the left-side powered plates and the right-side pass-band plates.

7. A vacuum sintering furnace with uniform coke removal and easy cleaning according to claim 6, characterized in that: The left-side power-carrying plate includes four corner porous power-carrying plates and two first porous power-carrying straight plates, the first porous power-carrying straight plates are arranged between the corner porous power-carrying plates, and the four corner porous power-carrying plates and the two first porous power-carrying straight plates are combined to form a first square shape; the corner porous power-carrying plate is provided with a first slot, and the shape of the first slot is adapted to the shape of the corner porous power-carrying plate; the first porous power-carrying straight plate is provided with a second slot, and the shape of the second slot is adapted to the shape of the first porous power-carrying straight plate, and the first slot and the second slot are used to accommodate the port of the graphite heating tube.

8. The vacuum sintering furnace with uniform coke removal and easy cleaning according to claim 7, characterized in that: The right-side power-carrying plate includes three second porous power-carrying straight plates, three graphite heating tube power-carrying plates and three second porous power-carrying straight plates are alternately spliced ​​to form a second square shape, and the area of ​​the first square shape is the same as that of the second square shape; the second porous power-carrying straight plate is provided with a third slot, and the shape of the third slot is adapted to the shape of the second porous power-carrying straight plate; the graphite heating tube power-carrying plate is provided with a fourth slot, and the shape of the fourth slot is adapted to the shape of the graphite heating tube power-carrying plate; the third slot and the fourth slot are used to accommodate the ports of the graphite heating tube.

9. The vacuum sintering furnace with uniform coke removal and easy cleaning according to claim 8, characterized in that: Threaded interfaces are provided at both ends of the graphite heating tube; the connecting assembly includes graphite heating tube port fixing nuts and bolts, and multiple groups of bolt fixing reserved openings are provided on both sides of the first slot, the second slot, the third slot and the fourth slot. The two ends of the graphite heating tube are threadedly positioned by the graphite heating tube port fixing nuts, and the graphite heating tube port fixing nuts are fixed in the bolt fixing reserved openings by bolts, so that the graphite heating tube is fixed in the corner multi-porous power-carrying plate, the first multi-porous power-carrying straight plate, the second multi-porous power-carrying straight plate and the graphite heating tube power connection plate.

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