Heat preservation well type carburizing furnace

Abstract

The invention relates to the technical field of pit type carburizing furnaces, and discloses a heat preservation pit type carburizing furnace which comprises a furnace body, a heating device is fixedly installed on the inner wall of the furnace body, a containing frame is placed in the furnace body, a furnace cover assembly is arranged outside the furnace body, and a spiral gas ejector pipe is placed in the furnace body. One end of the spiral gas ejector pipe extends out of the furnace body and communicates with a gas inlet pipe, the end, away from the spiral gas ejector pipe, of the gas inlet pipe communicates with a pressurizing gas pump, a check valve is arranged on the gas inlet pipe, and the spiral gas ejector pipe is in a spiral shape from top to bottom and located on the outer side of the containing frame. Carbon-rich gas is sprayed into the furnace at a stable and uniform flow rate through the gas holes uniformly distributed in the spiral gas spraying pipe, so that active carbon atoms can be in all-dimensional and uniform contact with the surface of a workpiece, the carburizing efficiency and uniformity are greatly improved, the carburizing uniformity of the workpiece can be ensured, and the carburizing quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of pit carburizing furnaces, and particularly to a heat-preserving pit carburizing furnace. Background Art

[0002] In modern industrial production, the heat treatment process of metal materials plays a crucial role in improving material properties. Among them, carburizing treatment, as a widely used surface strengthening technology, can significantly improve the surface hardness, wear resistance and fatigue strength of steel materials. The heat-preserving pit carburizing furnace is one of the key equipment to achieve efficient and precise carburizing treatment. In modern industrial production, the heat treatment process of metal materials plays a crucial role in improving material properties. Among them, carburizing treatment, as a widely used surface strengthening technology, can significantly improve the surface hardness, wear resistance and fatigue strength of steel materials. The heat-preserving pit carburizing furnace is one of the key equipment to achieve efficient and precise carburizing treatment. How to design a good gas flow channel to ensure that the temperature deviation in each area of the furnace is extremely small and the carburizing uniformity of the workpiece is guaranteed is one of the key points to improve production quality. Summary of the Invention

[0003] The purpose of the present invention is to provide a heat-preserving pit carburizing furnace to solve the problems raised in the above background art.

[0004] To achieve the above purpose, the present invention provides the following technical solution: A heat-preserving pit carburizing furnace, including a furnace body, a heating device is fixedly installed on the inner wall of the furnace body, a placement rack is placed in the furnace body, a furnace cover assembly is arranged outside the furnace body, a spiral air injection pipe is placed in the furnace body, one end of the spiral air injection pipe extends out of the furnace body, and this end is communicated with an air inlet pipe, the end of the air inlet pipe far from the spiral air injection pipe is communicated with a supercharging air pump, a check valve is arranged on the air inlet pipe, the spiral air injection pipe is spiraled from top to bottom, and the spiral air injection pipe is located outside the placement rack, and air holes are arranged at equal intervals on the spiral air injection pipe; A pressure stabilizing pipe is communicated in the furnace body, one end of the pressure stabilizing pipe far from the furnace body is communicated with a fixed cylinder, a piston is slidably arranged inside the fixed cylinder, an air outlet is arranged at the top of the fixed cylinder, and the inside of the fixed cylinder is communicated with a waste heat recovery assembly through a pipeline.

[0005] As a preferred implementation manner of the heat-preserving pit carburizing furnace provided by the present invention, the connection part of the pressure stabilizing pipe and the furnace body is close to the top of the furnace body, and a one-way valve is arranged on the pressure stabilizing pipe.

[0006] As a preferred embodiment of the heat-insulating well-type carburizing furnace provided by the present invention, the placement rack includes columns and suspension disks. There are three columns, and the three columns are circumferentially and arrayedly distributed. The suspension disks are fixedly connected to the three columns at the same time. There are multiple suspension disks, and they are equidistantly distributed on the columns from top to bottom.

[0007] As a preferred embodiment of the heat-insulating well-type carburizing furnace provided by the present invention, the furnace cover assembly includes a lifting cylinder. The output end of the lifting cylinder is fixedly installed with a mounting seat. The top of the mounting seat is rotationally connected with a rotating shaft through a bearing. The top end of the rotating shaft is fixedly installed with a connecting frame. The inner wall of the connecting frame is rotationally connected with a connecting rod through a bearing. The bottom end of the connecting rod is fixedly installed with a sealing cover. The sealing cover is arranged in the opening at the top of the furnace body.

[0008] As a preferred embodiment of the heat-insulating well-type carburizing furnace provided by the present invention, the outer wall of the fixed cylinder is fixedly sleeved with a heat-insulating outer shell. The inner wall of the fixed cylinder is fixedly installed with a support ring. The support ring is located below the piston and above the connection part between the pressure stabilizing pipe and the fixed cylinder.

[0009] As a preferred embodiment of the heat-insulating well-type carburizing furnace provided by the present invention, the furnace body is of a sandwich structure, and heat-insulating materials are filled between the inner and outer sandwich layers. The outer wall of the furnace body is fixedly installed with temperature sensors. The detection ends of the temperature sensors extend into the furnace body. There are multiple temperature sensors, and they are equidistantly distributed from top to bottom.

[0010] As a preferred embodiment of the heat-insulating well-type carburizing furnace provided by the present invention, a counterweight is fixedly installed on the outer wall of the mounting seat, and a rotating handle is fixedly installed at the top end of the connecting rod.

[0011] As a preferred embodiment of the heat-insulating well-type carburizing furnace provided by the present invention, the waste heat recovery assembly includes an exhaust pipe, a water tank, and a heat exchange pipe. The exhaust pipe is communicated with the inside of the fixed cylinder, and an electromagnetic valve is arranged at the communication part. One end of the exhaust pipe away from the fixed cylinder extends into the water tank. The water tank is filled with water. The heat exchange pipe is immersed in the water in the water tank. The top end of the heat exchange pipe is communicated with the exhaust pipe.

[0012] As a preferred embodiment of the heat-insulating well-type carburizing furnace provided by the present invention, the heat exchange pipe is in a spiral shape from top to bottom, and the bottom end of the heat exchange pipe is communicated with an air purifier.

[0013] As a preferred embodiment of the heat-insulating well-type carburizing furnace provided by the present invention, the outer wall of the water tank is communicated with a water inlet pipe and a water outlet pipe. The water inlet pipe and the water outlet pipe are communicated with the workshop circulating water path.

[0014] Meanwhile, through the above technical solution, the present invention has at least the following beneficial effects: The carbon-rich gas is sprayed into the furnace through the pores evenly distributed on the spiral spray pipe at a stable and uniform flow rate, enabling the active carbon atoms to contact the surface of the workpiece in all directions and evenly, greatly improving the carburizing efficiency and uniformity, ensuring the carburizing uniformity of the workpiece, and improving the carburizing quality; After the carbon-rich gas enters the furnace body, the gas in the furnace body increases. At this time, the air pressure in the furnace body rises, causing some gas to enter the fixed cylinder along the pressure stabilizing pipe, and then pushing up the piston, so that the excess air in the furnace body is stored in the fixed cylinder. This design can not only effectively prevent the air pressure in the furnace body from being too high during the carburizing process, but also keep the high-temperature gas in the same sealed space, preventing the heat of the high-temperature gas from dissipating, and making it more convenient for the temperature control system to control the temperature inside the furnace body; After the workpiece is processed, the solenoid valve is opened, so that the high-temperature gas in the fixed cylinder enters the exhaust pipe from the fixed cylinder, and then enters the heat exchange pipe, and the water in the water tank is heated through the heat exchange pipe to achieve the purpose of waste heat recovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic structural diagram of the present invention; Figure 2 of the present invention Figure 1 is a schematic structural diagram of the rear view; Figure 3 of the present invention Figure 1 is a schematic structural diagram of the front cross-sectional view; Figure 4 is a schematic structural diagram of the right-side cross-sectional view of the furnace body of the present invention; Figure 5 is a schematic structural diagram of the spiral spray pipe of the present invention; Figure 6 is a schematic structural diagram of the placement rack of the present invention; Figure 7 is a schematic structural diagram of the furnace cover assembly of the present invention; Figure 8 is a schematic structural diagram of the side cross-sectional view of the fixed cylinder and the piston of the present invention; Figure 9 is a schematic structural diagram of the waste heat recovery assembly and the fixed cylinder of the present invention; Figure 10 is a schematic structural diagram of the side cross-sectional view of the water tank of the present invention.

[0016] In the figure: 1. Furnace body; 2. Heating device; 3. Placing rack; 301. Column; 302. Hanging disc; 4. Furnace cover assembly; 401. Lifting cylinder; 402. Mounting seat; 403. Rotating shaft; 404. Connecting frame; 405. Connecting rod; 406. Sealing cover; 5. Waste heat recovery assembly; 501. Exhaust pipe; 502. Water tank; 503. Heat exchange tube; 6. Spiral air injection pipe; 7. Intake pipe; 8. Check valve; 9. Boost air pump; 10. Temperature sensor; 11. Voltage stabilizing tube; 12. Fixed cylinder; 13. Piston; 14. Air outlet; 15. One-way valve; 16. Counterweight; 17. Rotating handle; 18. Heat insulation housing; 19. Support ring; 20. Water inlet pipe; 21. Water outlet pipe; 22. Air purifier. Specific implementation mode

[0017] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0018] In order to enable those skilled in the art of this technology to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0019] It should be noted that, without conflict, the embodiments in the present invention and the features and technical solutions in the embodiments can be combined with each other.

[0020] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0021] Embodiment 1 Please refer to Figures 1-8 , the present invention provides a technical solution: a heat-insulated well-type carburizing furnace, including a furnace body 1, a heating device 2 is fixedly installed on the inner wall of the furnace body 1, a placing rack 3 is placed in the furnace body 1, a furnace cover assembly 4 is arranged outside the furnace body 1, a spiral air injection pipe 6 is placed in the furnace body 1, one end of the spiral air injection pipe 6 extends out of the furnace body 1, and this end is communicated with an intake pipe 7, the end of the intake pipe 7 away from the spiral air injection pipe 6 is communicated with a boost air pump 9, a check valve 8 is arranged on the intake pipe 7, the spiral air injection pipe 6 is in a spiral shape from top to bottom, and the spiral air injection pipe 6 is located outside the placing rack 3, and the spiral air injection pipe 6 is provided with equally spaced pores. By improving the common air injection pipe, the rich carbon gas is sprayed into the furnace through the pores evenly distributed on the spiral air injection pipe 6 at a stable and uniform flow rate, so that the active carbon atoms can contact the surface of the workpiece in all directions and evenly, greatly improving the carburizing efficiency and uniformity, ensuring the carburizing uniformity of the workpiece, and improving the carburizing quality; A voltage-stabilizing tube 11 is connected to the furnace body 1. One end of the voltage-stabilizing tube 11 away from the furnace body 1 is connected to a fixed cylinder 12. A piston 13 is slidably arranged inside the fixed cylinder 12. An air outlet 14 is provided on the top of the fixed cylinder 12. The interior of the fixed cylinder 12 is connected to a waste heat recovery component 5 through a pipeline. After the carbon-rich gas enters the furnace body 1, the gas in the furnace body 1 becomes more. At this time, the air pressure in the furnace body 1 rises, causing part of the gas to enter the fixed cylinder 12 along the voltage-stabilizing tube 11. Then, the piston 13 is lifted up, so that the excess air in the furnace body 1 is stored in the fixed cylinder 12. This design can not only effectively avoid excessive air pressure in the furnace body 1 during carburizing, but also allow high-temperature gas to remain in the same sealed space (inside the furnace body 1 and inside the fixed cylinder 12), thereby preventing the heat of the high-temperature gas from dissipating, and making it more convenient for the temperature control system to control the temperature inside the furnace body 1. The connection point between the voltage regulator tube 11 and the furnace body 1 is close to the top of the furnace body 1, so that the carbon-rich gas ejected from the spiral jet pipe 6 does not directly enter the voltage regulator tube 11, but the carbon-rich gas squeezes the original air in the furnace body 1 into the voltage regulator tube 11, thereby avoiding the ineffective consumption of the carbon-rich gas. A one-way valve 15 is provided on the voltage regulator tube 11 to prevent the gas in the fixed cylinder 12 from flowing back into the furnace body 1; The placement rack 3 includes a column 301 and a suspension plate 302. There are three columns 301, and the three columns 301 are arranged in a circular array. The suspension plate 302 is fixedly connected to the three columns 301 at the same time. There are multiple suspension plates 302, and they are evenly spaced from top to bottom on the columns 301. Multiple suspension plates 302 are arranged to suspend multiple workpieces to improve processing efficiency. The furnace cover assembly 4 includes a lifting cylinder 401, the output end of the lifting cylinder 401 is fixedly installed with a mounting seat 402, the top of the mounting seat 402 is rotatably connected to a rotating shaft 403 through a bearing, a connecting frame 404 is fixedly installed on the top of the rotating shaft 403, the inner wall of the connecting frame 404 is rotatably connected to a connecting rod 405 through a bearing, and a sealing cover 406 is fixedly installed on the bottom end of the connecting rod 405. The sealing cover 406 is arranged in the top opening of the furnace body 1, and the lifting power is provided by the lifting cylinder 401, so that the sealing cover 406 can be removed from the furnace body 1 when taking and placing tools, and because the connecting frame 404 is rotatable, the sealing cover 406 can revolve and then stagger with the top opening of the furnace body 1 to prevent the sealing cover 406 from hindering the workers from taking and placing workpieces, and because the connecting rod 405 is rotatably connected to the connecting frame 404, the sealing cover 406 can rotate, which is used to adjust the position and angle of the buckle structure on the sealing cover 406 as needed; The outer wall of the fixed cylinder 12 is fixedly sleeved with a heat-insulating outer shell 18. The inner wall of the fixed cylinder 12 is fixedly installed with a support ring 19. The support ring 19 is located below the piston 13 and above the connection part between the voltage stabilizing tube 11 and the fixed cylinder 12. The heat-insulating outer shell 18 can effectively prevent the heat of the high-temperature gas in the fixed cylinder 12 from dissipating. The support ring 19 can limit the lowest position of the piston 13 to prevent the piston 13 from moving below the bottom end of the voltage stabilizing tube 11, so that the gas in the voltage stabilizing tube 11 directly discharges from the air outlet 14 after entering the fixed cylinder 12; The furnace body 1 has a sandwich structure, and heat-insulating materials are filled between the inner and outer sandwich layers to further improve the heat preservation effect of the furnace body 1. The outer wall of the furnace body 1 is fixedly installed with a temperature sensor 10. The detection end of the temperature sensor 10 extends into the furnace body 1. There are multiple temperature sensors 10, which are evenly distributed at equal intervals from top to bottom. By monitoring the temperature in different depth areas of the furnace body 1, it is convenient for workers to control the temperature in the furnace body 1 and avoid the problem that the processing effect deteriorates due to too large temperature difference between the upper and lower parts of the furnace body 1; A counterweight 16 is fixedly installed on the outer wall of the mounting seat 402 to balance the center of gravity of the entire structure on the mounting seat 402. The top end of the connecting rod 405 is fixedly installed with a rotating handle 17, which is convenient for workers to apply force to rotate the connecting rod 405 or pull the connecting frame 404 to rotate.

[0022] Working principle: When in use, after hanging the workpiece on the hanging disc 302, the sealing cover 406 is snapped into the top opening of the furnace body 1. The heating device 2 is turned on to heat the inside of the furnace body 1. After heating to the set temperature, the pressurized air pump 9 is turned on to pressurize the carbon-rich gas and introduce it into the spiral air pipe 6 from the air inlet pipe 7. The carbon-rich gas is sprayed into the furnace at a stable and uniform flow rate through the evenly distributed air holes on the spiral air pipe 6, so that the active carbon atoms can contact the surface of the workpiece comprehensively and evenly, greatly improving the carburizing efficiency and uniformity, ensuring the carburizing uniformity of the workpiece and improving the carburizing quality. During the process of spraying the carbon-rich gas, the gas in the furnace body 1 increases, and at this time, the air pressure in the furnace body 1 rises, so that part of the gas enters the fixed cylinder 12 along the voltage stabilizing tube 11, and then the piston 13 is pushed up, so that the excess air in the furnace body 1 is stored in the fixed cylinder 12.

[0023] Embodiment 2 Please refer to Figures 1-10, the present invention provides a technical solution: a heat-insulated well-type carburizing furnace, including a furnace body 1, a heating device 2 is fixedly installed on the inner wall of the furnace body 1, a placement rack 3 is placed in the furnace body 1, a furnace cover assembly 4 is arranged outside the furnace body 1, a spiral air injection pipe 6 is placed in the furnace body 1, one end of the spiral air injection pipe 6 extends out of the furnace body 1, and this end is communicated with an air inlet pipe 7, the end of the air inlet pipe 7 far from the spiral air injection pipe 6 is communicated with a booster air pump 9, a check valve 8 is arranged on the air inlet pipe 7, the spiral air injection pipe 6 is spirally arranged from top to bottom, and the spiral air injection pipe 6 is located outside the placement rack 3, and the spiral air injection pipe 6 is provided with pores distributed at equal intervals. By improving the common air injection pipe, the carburizing-rich gas is sprayed into the furnace through the pores uniformly distributed on the spiral air injection pipe 6 at a stable and uniform flow rate, so that the active carbon atoms can contact the surface of the workpiece in all directions and uniformly, greatly improving the carburizing efficiency and uniformity, ensuring the carburizing uniformity of the workpiece, and improving the carburizing quality; A pressure stabilizing pipe 11 is communicated in the furnace body 1, one end of the pressure stabilizing pipe 11 far from the furnace body 1 is communicated with a fixed cylinder 12, a piston 13 is slidably arranged inside the fixed cylinder 12, an air outlet 14 is opened at the top of the fixed cylinder 12, and the inside of the fixed cylinder 12 is communicated with a waste heat recovery assembly 5 through a pipeline. After the carburizing-rich gas enters the furnace body 1, the gas in the furnace body 1 increases, and at this time the air pressure in the furnace body 1 rises, so that part of the gas enters the fixed cylinder 12 along the pressure stabilizing pipe 11, and then the piston 13 is pushed up, so that the excess air in the furnace body 1 is stored in the fixed cylinder 12. This design can not only effectively prevent the air pressure in the furnace body 1 from being too large during the carburizing process, but also keep the high-temperature gas in the same sealed space (inside the furnace body 1 and inside the fixed cylinder 12), avoiding the heat dissipation of the high-temperature gas, and making it more convenient for the temperature control system to control the temperature inside the furnace body 1; The connection between the pressure stabilizing pipe 11 and the furnace body 1 is close to the top of the furnace body 1, so that the carburizing-rich gas sprayed from the spiral air injection pipe 6 will not directly enter the pressure stabilizing pipe 11, but the carburizing-rich gas squeezes the original air in the furnace body 1 into the pressure stabilizing pipe 11, thereby avoiding the ineffective consumption of the carburizing-rich gas. A one-way valve 15 is arranged on the pressure stabilizing pipe 11 to prevent the gas in the fixed cylinder 12 from flowing back into the furnace body 1; The placement rack 3 includes columns 301 and suspension discs 302. There are three columns 301, and the three columns 301 are circumferentially arranged in an array. The suspension discs 302 are fixedly connected to the three columns 301 at the same time. There are multiple suspension discs 302, and they are equally spaced from top to bottom on the columns 301. The multiple suspension discs 302 are provided for hanging multiple workpieces to improve the processing efficiency; The furnace cover assembly 4 includes a lifting cylinder 401, the output end of the lifting cylinder 401 is fixedly installed with a mounting seat 402, the top of the mounting seat 402 is rotatably connected to a rotating shaft 403 through a bearing, a connecting frame 404 is fixedly installed on the top of the rotating shaft 403, the inner wall of the connecting frame 404 is rotatably connected to a connecting rod 405 through a bearing, and a sealing cover 406 is fixedly installed on the bottom end of the connecting rod 405. The sealing cover 406 is arranged in the top opening of the furnace body 1, and the lifting power is provided by the lifting cylinder 401, so that the sealing cover 406 can be removed from the furnace body 1 when taking and placing tools, and because the connecting frame 404 is rotatable, the sealing cover 406 can revolve and then stagger with the top opening of the furnace body 1 to prevent the sealing cover 406 from hindering the workers from taking and placing workpieces, and because the connecting rod 405 is rotatably connected to the connecting frame 404, the sealing cover 406 can rotate, which is used to adjust the position and angle of the buckle structure on the sealing cover 406 as needed; The outer wall of the fixed cylinder 12 is fixedly sleeved with a heat-insulating shell 18, and the inner wall of the fixed cylinder 12 is fixedly installed with a support ring 19, which is located below the piston 13, and above the connection between the voltage-stabilizing tube 11 and the fixed cylinder 12. The provision of the heat-insulating shell 18 can effectively prevent the heat of the high-temperature gas in the fixed cylinder 12 from being dissipated, and the provision of the support ring 19 can limit the lowest position of the piston 13, preventing the piston 13 from moving below the bottom end of the voltage-stabilizing tube 11, thereby causing the gas in the voltage-stabilizing tube 11 to enter the fixed cylinder 12 and be directly discharged from the gas outlet 14; The furnace body 1 is a sandwich structure, and the inner and outer interlayers are filled with heat insulation materials to further improve the heat preservation effect of the furnace body 1. A temperature sensor 10 is fixedly installed on the outer wall of the furnace body 1. The detection end of the temperature sensor 10 extends into the furnace body 1. There are multiple temperature sensors 10, which are evenly spaced from top to bottom. By monitoring the temperature of different depth areas in the furnace body 1, it is convenient for workers to control the temperature in the furnace body 1, avoiding the problem of excessive temperature difference between the upper and lower parts of the furnace body 1, which leads to poor processing effect. A counterweight 16 is fixedly mounted on the outer wall of the mounting seat 402, so that the center of gravity of the entire mounting seat 402 is balanced. A rotating handle 17 is fixedly mounted on the top of the connecting rod 405, so that it is convenient for workers to apply force to rotate the connecting rod 405 or pull the connecting frame 404 to rotate; The waste heat recovery component 5 includes an exhaust pipe 501, a water tank 502, and a heat exchange pipe 503. The exhaust pipe 501 is communicated with the inside of the fixed cylinder 12, and a solenoid valve is arranged at the communication position. One end of the exhaust pipe 501 away from the fixed cylinder 12 extends into the water tank 502. The water tank 502 is filled with water. The heat exchange pipe 503 is immersed in the water in the water tank 502. The top end of the heat exchange pipe 503 is communicated with the exhaust pipe 501. After the workpiece is processed, the solenoid valve is opened, so that the high-temperature gas in the fixed cylinder 12 enters the exhaust pipe 501 from the fixed cylinder 12, and then enters the heat exchange pipe 503. The water in the water tank 502 is heated through the heat exchange pipe 503, achieving the purpose of waste heat recovery; The heat exchange pipe 503 is in a spiral shape from top to bottom, increasing the contact area between the heat exchange pipe 503 and water, improving the heat exchange effect. The bottom end of the heat exchange pipe 503 is communicated with an air purifier 22 to purify the gas after heat exchange; The outer wall of the water tank 502 is communicated with a water inlet pipe 20 and a water outlet pipe 21. The water inlet pipe 20 and the water outlet pipe 21 are communicated with the workshop circulating water path, so that the water in the water tank 502 circulates. That is, cold water enters the water tank 502, and hot water flows out of the water tank 502, so that the heat exchange pipe 503 can maintain a large temperature difference with the water in the water tank 502, thereby ensuring the heat exchange efficiency.

[0024] The use process of an insulating pit-type carburizing furnace provided by the present invention is as follows: Working principle: When in use, after hanging the workpiece on the hanging plate 302, the sealing cover 406 is clamped into the top opening of the furnace body 1. The heating device 2 is turned on to heat the inside of the furnace body 1. After heating to the set temperature, the pressurizing air pump 9 is turned on to pressurize the carbon-rich gas and introduce it into the spiral spray pipe 6 from the air inlet pipe 7. The carbon-rich gas is sprayed into the furnace through the pores uniformly distributed on the spiral spray pipe 6 at a stable and uniform flow rate, so that the active carbon atoms can contact the surface of the workpiece in all directions and uniformly, greatly improving the carburizing efficiency and uniformity, ensuring the carburizing uniformity of the workpiece, and improving the carburizing quality. During the process of spraying the carbon-rich gas, the gas in the furnace body 1 increases, and at this time, the air pressure in the furnace body 1 rises, so that part of the gas enters the fixed cylinder 12 along the pressure stabilizing pipe 11, and then the piston 13 is pushed up, so that the excess air in the furnace body 1 is stored in the fixed cylinder 12. After the workpiece is processed, the solenoid valve is opened, so that the high-temperature gas in the fixed cylinder 12 enters the exhaust pipe 501 from the fixed cylinder 12, and then enters the heat exchange pipe 503. The water in the water tank 502 is heated through the heat exchange pipe 503, achieving the purpose of waste heat recovery.

[0025] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A heat-insulated well-type carburizing furnace, comprising a furnace body (1), wherein a heating device (2) is fixedly installed on the inner wall of the furnace body (1), and a placement rack (3) is placed in the furnace body (1), and is characterized in that: Outside the furnace body (1), a furnace cover assembly (4) is provided. Inside the furnace body (1), a spiral air injection pipe (6) is placed. One end of the spiral air injection pipe (6) extends out of the furnace body (1), and an air inlet pipe (7) is connected to this end. The end of the air inlet pipe (7) far from the spiral air injection pipe (6) is connected to a booster air pump (9). A check valve (8) is provided on the air inlet pipe (7). The spiral air injection pipe (6) is spiraled from top to bottom and is located outside the placement rack (3). The spiral air injection pipe (6) is provided with evenly spaced air holes. Inside the furnace body (1), a pressure stabilizing pipe (11) is connected. One end of the pressure stabilizing pipe (11) far from the furnace body (1) is connected to a fixed cylinder (12). A piston (13) is slidably arranged inside the fixed cylinder (12). An air outlet (14) is provided at the top of the fixed cylinder (12). The inside of the fixed cylinder (12) is connected to a waste heat recovery assembly (5) through a pipeline.

2. The well-type carburizing furnace with heat preservation according to claim 1, wherein: The connection between the pressure stabilizing pipe (11) and the furnace body (1) is close to the top of the furnace body (1). A one-way valve (15) is provided on the pressure stabilizing pipe (11).

3. A heat-insulated pit-type carburizing furnace according to claim 1, characterized in that: The placement rack (3) includes upright columns (301) and suspension discs (302). There are three upright columns (301), and the three upright columns (301) are circumferentially arranged in an array. The suspension disc (302) is fixedly connected to the three upright columns (301) at the same time. There are multiple suspension discs (302), and they are evenly spaced from top to bottom on the upright columns (301).

4. A heat-insulated pit-type carburizing furnace according to claim 1, characterized in that: The furnace cover assembly (4) includes a lifting cylinder (401). The output end of the lifting cylinder (401) is fixedly installed with a mounting seat (402). The top of the mounting seat (402) is rotatably connected to a rotating shaft (403) through a bearing. The top end of the rotating shaft (403) is fixedly installed with a connecting frame (404). The inner wall of the connecting frame (404) is rotatably connected to a connecting rod (405) through a bearing. The bottom end of the connecting rod (405) is fixedly installed with a sealing cover (406). The sealing cover (406) is arranged inside the top opening of the furnace body (1).

5. A heat-insulated pit-type carburizing furnace according to claim 1, characterized in that: An insulating outer shell (18) is fixedly sleeved on the outer wall of the fixed cylinder (12). A support ring (19) is fixedly installed on the inner wall of the fixed cylinder (12). The support ring (19) is located below the piston (13) and above the connection between the pressure stabilizing pipe (11) and the fixed cylinder (12).

6. The well-type carburizing furnace with heat preservation according to claim 1, wherein: The furnace body (1) is of a sandwich structure, and heat insulating materials are filled between the inner and outer sandwich layers. A temperature sensor (10) is fixedly installed on the outer wall of the furnace body (1). The detection end of the temperature sensor (10) extends into the furnace body (1). There are multiple temperature sensors (10), and they are evenly spaced from top to bottom.

7. The well-type carburizing furnace with heat preservation according to claim 4, characterized in that: A counterweight (16) is fixedly installed on the outer wall of the mounting seat (402). A rotating handle (17) is fixedly installed at the top end of the connecting rod (405).

8. A heat-insulated pit-type carburizing furnace according to claim 1, characterized in that: The waste heat recovery component (5) includes an exhaust pipe (501), a water tank (502), and a heat exchange pipe (503). The exhaust pipe (501) is communicated with the inside of the fixed cylinder (12), and a solenoid valve is provided at the communication point. One end of the exhaust pipe (501) away from the fixed cylinder (12) extends into the water tank (502). The water tank (502) is filled with water, and the heat exchange pipe (503) is immersed in the water of the water tank (502). The top end of the heat exchange pipe (503) is communicated with the exhaust pipe (501).

9. The well-type carburizing furnace with heat preservation according to claim 8, wherein: The heat exchange pipe (503) is in a spiral shape from top to bottom, and an air purifier (22) is communicated with the bottom end of the heat exchange pipe (503).

10. A heat-insulated pit-type carburizing furnace according to claim 8, characterized in that: The outer wall of the water tank (502) is communicated with a water inlet pipe (20) and a water outlet pipe (21), and the water inlet pipe (20) and the water outlet pipe (21) are communicated with the workshop circulating water path.

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