Joule heat tube furnace capable of rapidly heating and cooling

Abstract

The utility model provides a Joule hot tube furnace capable of quickly heating and cooling. The Joule hot tube furnace comprises a case, a high-temperature reaction chamber and a vacuum pump, an electrical system is installed in the case, the high-temperature reaction chamber comprises a quartz tube, a graphite heating tube and graphite conductive stations are installed in the quartz tube, the two ends of the graphite heating tube are arranged in mounting holes in one ends of the centers of the two graphite conductive stations respectively, and the other ends of the two graphite conductive stations are each fixedly provided with a metal conductive rod; the two metal conducting rods are connected with an electrical system, the two ends of the high-temperature reaction chamber are sealed through flange assemblies, air channels are machined in the flange assemblies and the graphite conducting tables to communicate the interior of the graphite heating pipe with the exterior of the high-temperature reaction chamber, the air channels in the two flange assemblies are connected with an air inlet valve and an air outlet valve through air pipes respectively, and the air outlet valve is connected with a vacuum pump. The graphite heating tube is a heating device and a device for containing materials, the rapidly-increased temperature can directly act on the materials, and the material calcination efficiency is greatly improved.

Description

Technical Field

[0001] The utility model relates to a Joule heat pipe furnace which can quickly heat up and cool down. Background Art

[0002] High-temperature calcination of materials in a vacuum or various atmospheres is a common research method in chemical and chemical experiments, and the tubular furnace is a commonly used device in such research. At present, most tubular furnaces place the materials to be calcined into the furnace tube, and then use resistance wires to heat the furnace tubes and then heat the materials in the furnace tubes; however, such tubular furnaces often have slow heating and cooling speeds, and the maximum operating temperature of the tubular furnace is limited by the heat resistance temperature of the furnace tube and the resistance wire, and the operating temperature is often below 1600°C. Compared with traditional tubular furnaces, the heating element of the Joule heat device uses graphite tubes / graphite paper, and the material is directly installed in the graphite tube / graphite paper. It has a small heat capacity and can achieve rapid heating and cooling, and can be heated to a higher temperature. Although some manufacturers have developed Joule heat devices, their structures are often more complicated and the manufacturing cost is high, which restricts the promotion and application of Joule heat devices in chemical and chemical laboratories. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a Joule heat pipe furnace which can quickly heat up and cool down.

[0004] The utility model is realized through the following technical solutions.

[0005] The utility model provides a Joule heat tube furnace capable of rapidly heating and cooling, comprising a chassis, a high-temperature reaction chamber, and a vacuum pump; an electrical system is installed in the chassis, the high-temperature reaction chamber comprises a quartz tube, a graphite heating tube and a graphite conductive table are installed in the quartz tube, two ends of the graphite heating tube are respectively placed in one end of a central air guide hole of two graphite conductive tables, a metal conductive rod is fixedly installed at the other end of the two air guide holes, and the two metal conductive rods are connected to the electrical system; the two ends of the high-temperature reaction chamber are closed by a flange assembly, air ducts are machined on the flange assembly and the graphite conductive table to conduct the inside of the graphite heating tube with the outside of the high-temperature reaction chamber, the air ducts on the two flange assemblies are respectively connected to the air inlet valve and the air outlet valve through air pipes, and the air outlet valve is connected to the vacuum pump.

[0006] The flange assembly includes a flange cover and an outer flange. A sealing ring is provided between the inner wall of the flange cover and the outer wall of the high-temperature reaction chamber. The flange end of the flange cover is connected to the outer flange by bolts. The outer flange cover is on the outlet of the high-temperature reaction chamber. A through hole is processed at the center of the outer flange, and one end of the metal conductive rod extends out of the high-temperature reaction chamber from the through hole.

[0007] A truncated cone is processed at each of the two ends of the graphite conductive table, and the outer wall of the truncated cone is tightly matched with the inner wall of the high-temperature reaction chamber.

[0008] The air passage includes an air outlet, an air inlet, and a small air hole. The air outlet is processed on the end face of the outer flange, the air inlet is processed on a circular table of a graphite conductive table adjacent to one end of the outer flange, and the small air hole is processed on the side wall of the graphite conductive table and is connected to the air guide hole.

[0009] The high temperature reaction chamber is supported on the chassis through a support column, the bottom of the support column is fixed to the top of the chassis, and the top of the support column is provided with a hoop, which embraces the outer wall of the high temperature reaction chamber.

[0010] The electrical system includes: a pressure gauge, a temperature control instrument, and a power switch installed on the front panel of the chassis, a high-power AC / DC switching power supply and a switching power supply installed at the bottom of the chassis, and an infrared temperature sensor installed on the top of the chassis and directly below the graphite heating tube. The input end of the power switch is connected to the power supply through a cable, and the output end of the power switch is respectively connected to the temperature control instrument, the high-power AC / DC switching power supply and the switching power supply. The output end of the switching power supply is connected to the power line of the infrared temperature sensor, the signal output end of the infrared temperature sensor is connected to the signal input end of the temperature control instrument, the signal output end of the temperature control instrument is connected to the signal input end of the high-power AC / DC switching power supply, and the power output end of the high-power AC / DC switching power supply is respectively connected to the metal conductive rods at both ends of the high-temperature reaction chamber.

[0011] The output end of the temperature controller is connected to a wire nose through a cable. Two wire noses extend from the top of the chassis and are fixed on two metal conductive rods through nuts.

[0012] The pressure gauge is connected to the air pipe between the air intake valve and the high temperature reaction chamber. A three-way joint is provided on the air pipe between the air intake valve and the high temperature reaction chamber. The pressure gauge is connected to the three-way joint through the air pipe.

[0013] A handle is also installed on the outer walls of both sides of the chassis respectively.

[0014] The air inlet valve and the air outlet valve are both fixed on the two side walls of the chassis through mounting ears, and the mounting ears are L-shaped plates.

[0015] The beneficial effect of the utility model is that the graphite heating tube is a heating device and also a device for containing materials. The rapidly rising temperature can directly act on the materials, greatly improving the calcination efficiency of the materials. After the calcination is completed, the cooling speed is also improved due to the small mass of the heating tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the utility model;

[0017] Figure 2 It is a schematic diagram of the right side structure of the utility model;

[0018] Figure 3 This is a schematic diagram of the back plate structure of the utility model;

[0019] Figure 4 This is a schematic diagram of the electrical system principle of the utility model;

[0020] Figure 5 This is a schematic diagram of the high temperature reaction chamber structure of the utility model;

[0021] Figure 6 This is a schematic diagram of the gas circuit principle of the utility model;

[0022] In the figure: 1-chassis, 2-high temperature reaction chamber, 3-vacuum pump, 4-air pipe, 5-tee joint, 6-inlet valve, 7-pressure gauge, 8-exhaust valve, 9-temperature control instrument, 10-power switch, 11-handle, 12-gland head, 13-wire nose, 14-air outlet, 15-infrared temperature sensor, 16-support column, 17-hoop, 18-mounting ear, 19-cable inlet, 20-cooling fan, 21-high power AC / DC power converter, 22-switching power supply, 23-sealing ring, 24-air outlet, 25-small air hole, 26-quartz tube, 27-air inlet, 28-flange cover, 29-outer flange, 30-air outlet, 31-metal conductive rod, 32-graphite conductive table, 33-graphite heating tube, 34-round table, 35-ring groove, 36-air guide hole. DETAILED DESCRIPTION

[0023] The technical solution of the utility model is further described below, but the scope of protection required is not limited to the description.

[0024] like Figure 1As shown, a Joule heat tube furnace capable of rapid heating and cooling comprises a chassis 1, a high temperature reaction chamber 2 and a vacuum pump 3; an electrical system is installed in the chassis 1, the high temperature reaction chamber 2 comprises a quartz tube 26, a graphite heating tube 33 and a graphite conductive platform 32 are installed in the quartz tube 26, two ends of the graphite heating tube 33 are respectively placed in one end of the central air guide holes 36 of the two graphite conductive platforms 32, and a metal conductive rod 31 is fixedly installed at the other end of the two air guide holes 36, the two metal conductive rods 31 are connected to the electrical system, the two ends of the high temperature reaction chamber 2 are closed by flange assemblies, the flange assembly and the graphite conductive platform 32 are machined with air ducts to conduct the inside of the graphite heating tube 33 with the outside of the high temperature reaction chamber 2, the air ducts on the two flange assemblies are respectively connected to the air inlet valve 6 and the air outlet valve 8 through air pipes, and the air outlet valve 8 is connected to the vacuum pump 3. During the use of the Joule heat tube furnace, the graphite conductive table, metal conductive rod, graphite heating tube and DC power supply are connected to form a closed circuit with wires; the high-power AC / DC power converter converts 220-380V AC power into 5-48V DC power; the infrared temperature probe can measure the temperature of the graphite heating tube and transmit its electrical signal to the temperature controller, which can display the measured temperature and control the current output of the DC power supply, thereby controlling the temperature of the graphite heating tube.

[0025] In order to ensure the sealing of the high-temperature reaction chamber, the flange assembly includes a flange cover 28 and an outer flange 29. A sealing ring 23 is provided between the inner wall of the flange cover 28 and the outer wall of the high-temperature reaction chamber 2. The flange end of the flange cover 28 is connected to the outer flange 29 by bolts. The outer flange 29 covers the outlet of the high-temperature reaction chamber 2. A through hole is processed at the center of the outer flange 29, and one end of the metal conductive rod 31 extends out of the high-temperature reaction chamber 2 from the through hole.

[0026] A truncated cone 34 is processed at each end of the graphite conductive platform 32, and the outer wall of the truncated cone 34 is tightly matched with the inner wall of the high temperature reaction chamber 2. The graphite conductive platform 32 supports the graphite heating tube and the metal conductive rod in the quartz tube.

[0027] Since it is necessary to ensure that the high-purity reaction gas is in the high-temperature reaction chamber during the experiment, the gas passage includes an outlet 30, an inlet 27, and a small air hole 25. The outlet 30 is processed on the end face of the outer flange 29, the inlet 27 is processed on the graphite conductive platform 32 adjacent to the truncated platform 34 at one end of the outer flange 29, and the small air hole 25 is processed on the side wall of the graphite conductive platform 32 and connected to the gas guide hole 36. The vacuum pump evacuates the high-temperature reaction chamber through the outlet, and the steel cylinder filled with reaction gas is connected to the inlet through the air pipe. After the pure gas is filled into the high-temperature reaction chamber, the outlet valve is closed, and the steel cylinder containing gas is removed. The purity of the reaction gas in the high-temperature reaction chamber is ensured.

[0028] The high temperature reaction chamber 2 is supported on the chassis 1 by a support column 16, the bottom of the support column 16 is fixed to the top of the chassis 1, and a clamp 17 is provided on the top of the support column 16, and the clamp 17 is surrounded on the outer wall of the high temperature reaction chamber 2. The opening of the clamp is a movable opening, and the high temperature reaction chamber can be removed for filling and cleaning before and after the experiment.

[0029] like Figure 5 As shown, the temperature control instrument 9 adopts YUDIAN AI-858 temperature controller, in which the red color is AC live wire, the black color is AC neutral wire, and the blue color is ground wire. The electrical system includes a pressure gauge 7, a temperature control instrument 9, a power switch 10 installed on the front panel of the chassis 1, a high-power AC / DC power converter 21 and a switching power supply 22 installed at the bottom of the chassis 1, and an infrared temperature sensor 15 installed on the top of the chassis 1 and directly below the graphite heating tube 33. The input end of the power switch 10 is connected to the power supply through a cable, and the output end of the power switch 10 is respectively connected to the temperature control instrument 9, the high-power AC / DC power converter 21, and the switching power supply 22. The output end of the switching power supply 22 is connected to the infrared temperature sensor 15, and the signal end of the infrared temperature sensor 15 is connected to the signal input end of the temperature control instrument 9. The signal output end of the temperature control instrument 9 is connected to the signal input end of the high-power AC / DC power converter 21, and the power output end of the high-power AC / DC power converter 21 is respectively connected to the metal conductive rods 31 at both ends of the high-temperature reaction chamber 2. The power switch 10 is a main switch, and the high-power AC / DC power converter 21 outputs an adjustable current of 50A to 500A.

[0030] The output end of the high-power AC / DC power converter 21 is connected to the wire nose 13 through a cable. Two wire noses 13 extend from the top of the chassis 1 and are fixed to two metal conductive rods 31 through nuts. A gland is installed on the top of the chassis. The cable passes through the gland and is connected to the wire nose. The gland ensures the sealing of the top of the chassis.

[0031] The pressure gauge 7 is connected to the air pipe between the air intake valve 6 and the high temperature reaction chamber 2. A three-way joint 5 is provided on the air pipe between the air intake valve 6 and the high temperature reaction chamber 2. The pressure gauge 7 is connected to the three-way joint 5 through the air pipe. The pressure in the high temperature reaction chamber is detected by the pressure gauge. When the negative pressure is too low, the air intake valve is opened to release the pressure.

[0032] In order to facilitate the staff to move the chassis, a handle 11 is installed on the outer walls of both sides of the chassis 1.

[0033] The air inlet valve 6 and the air outlet valve 8 are both fixed to the two side walls of the chassis 1 through mounting ears 18, and the mounting ears 18 are L-shaped plates.

[0034] Example:

[0035] The wall thickness of the graphite tube used is 0.5-10 mm, and the inner diameter of the graphite tube is 3-100 mm; the resistance of the graphite tube is much greater than the sum of the resistances of the graphite conductive table, the metal conductive rod and the special cable.

[0036] (1) Loading: Remove the quartz tube and take out the graphite heating tube. After loading the material to be calcined into the graphite heating tube, fix the graphite heating tube between two graphite conductive tables, fix the metal conductive rod, graphite conductive table, graphite heating tube and graphite tube in the quartz tube, and fix the special sealing flange of the tube furnace on the quartz tube. Connect the wire noses to the two metal conductive rods respectively to form an energized circuit.

[0037] (2) Experimental process

[0038] ①Evacuation: Turn on the vacuum pump, open the right valve and close the left valve to start evacuating the tube furnace; after the evacuation is completed, close the outlet valve; open the cylinder valve (the pressure reduction valve should not exceed 0.3MPa), open the inlet valve to inflate the quartz tube; after the vacuum gauge returns to 0MPa, close the inlet valve, open the outlet valve and vacuum pump to evacuate the tube for the second time. Repeat this process to evacuate and inflate the quartz tube three times.

[0039] ②Power start: When the pressure gauge shows -0.075MPa and no longer changes, connect the power and turn on the power switch.

[0040] ③Set the heating program: set the required temperature and heating time on the temperature controller.

[0041] ④Material calcination: Click the run button on the temperature controller to start heating the graphite heating tube and the material inside it.

Claims

1. A Joule heat pipe furnace capable of rapid heating and cooling, comprising a chassis (1), a high temperature reaction chamber (2), and a vacuum pump (3), characterized in that: An electrical system is installed in the chassis (1); the high-temperature reaction chamber (2) comprises a quartz tube (26); a graphite heating tube (33) and a graphite conductive platform (32) are installed in the quartz tube (26); two ends of the graphite heating tube (33) are respectively placed in one end of a central air guide hole (36) of two graphite conductive platforms (32); a metal conductive rod (31) is fixedly installed at the other end of each of the two air guide holes (36); the two metal conductive rods (31) are respectively connected to the electrical system; the two ends of the high-temperature reaction chamber (2) are closed by a flange assembly; air channels are machined on the flange assembly and the graphite conductive platform (32) to connect the inside of the graphite heating tube (33) with the outside of the high-temperature reaction chamber (2); the air channels on the two flange assemblies are respectively connected to an air inlet valve (6) and an air outlet valve (8) through air pipes; and the air outlet valve (8) is connected to a vacuum pump (3).

2. The Joule heat tube furnace capable of rapid heating and cooling as claimed in claim 1, characterized in that: The flange assembly comprises a flange cover (28) and an outer flange (29), a sealing ring (23) is provided between the inner wall of the flange cover (28) and the outer wall of the high-temperature reaction chamber (2), the flange end of the flange cover (28) is connected to the outer flange (29) by bolts, the outer flange (29) covers the outlet of the high-temperature reaction chamber (2), a through hole is processed at the center of the outer flange (29), and one end of the metal conductive rod (31) extends out of the high-temperature reaction chamber (2) from the through hole.

3. The Joule heat tube furnace capable of rapid heating and cooling as claimed in claim 1, characterized in that: A truncated cone (34) is processed at each of the two ends of the graphite conductive cone (32), and the outer wall of the truncated cone (34) is tightly matched with the inner wall of the high-temperature reaction chamber (2).

4. The Joule heat tube furnace capable of rapid heating and cooling as claimed in claim 1, characterized in that: The air passage comprises an air outlet (30), an air inlet (27), and a small air hole (25); the air outlet (30) is processed on the end surface of the outer flange (29); the air inlet (27) is processed on a graphite conductive platform (32) adjacent to a truncated platform (34) at one end of the outer flange (29); and the small air hole (25) is processed on the side wall of the graphite conductive platform (32) and is connected to the air guide hole (36).

5. The Joule heat tube furnace capable of rapid heating and cooling as claimed in claim 1, characterized in that: The high temperature reaction chamber (2) is supported on the chassis (1) via a support column (16); the bottom of the support column (16) is fixed to the top of the chassis (1); a clamp (17) is provided on the top of the support column (16); and the clamp (17) surrounds the outer wall of the high temperature reaction chamber (2).

6. The Joule heat tube furnace capable of rapid heating and cooling as claimed in claim 1, characterized in that: The electrical system comprises: a pressure gauge (7), a temperature control instrument (9), and a power switch (10) installed on the front panel of the chassis (1); a high-power AC / DC switching power supply (21) and a switching power supply (22) installed at the bottom of the chassis (1); and an infrared temperature sensor (15) installed on the top of the chassis (1) and directly below the graphite heating tube (33); the input end of the power switch (10) is connected to the power supply via a cable; the output end of the power switch (10) is respectively connected to the temperature control instrument (9), the high-power AC / DC switching power supply (21) and the switching power supply (22); the output end of the switching power supply (22) is connected to the power line of the infrared temperature sensor (15); the signal output end of the infrared temperature sensor (15) is connected to the signal input end of the temperature control instrument (9); the signal output end of the temperature control instrument (9) is connected to the signal input end of the high-power AC / DC switching power supply (21); and the power output end of the high-power AC / DC switching power supply (21) is respectively connected to the metal conductive rods (31) at both ends of the high-temperature reaction chamber (2).

7. The Joule heat tube furnace capable of rapid heating and cooling as claimed in claim 6, characterized in that: The output end of the high-power AC / DC switching power supply (21) is connected to a wire nose (13) via a cable. Two wire noses (13) extend from the top of the chassis (1) and are respectively fixed to two metal conductive rods (31) via nuts.

8. The Joule heat tube furnace capable of rapid heating and cooling as claimed in claim 6, characterized in that: The pressure gauge (7) is connected to the air pipe between the air intake valve (6) and the high-temperature reaction chamber (2); a three-way joint (5) is provided on the air pipe between the air intake valve (6) and the high-temperature reaction chamber (2); and the pressure gauge (7) is connected to the three-way joint (5) via the air pipe.

9. The Joule heat tube furnace capable of rapid heating and cooling as claimed in claim 1, characterized in that: A handle (11) is also installed on the outer walls of both sides of the chassis (1).

10. The Joule heat tube furnace capable of rapid heating and cooling as claimed in claim 1, characterized in that: The air inlet valve (6) and the air outlet valve (8) are both fixed on the two side walls of the chassis (1) via mounting ears (18), and the mounting ears (18) are L-shaped plates.

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