Intelligent temperature control sintering furnace for powder sintered products
By using composite isolation components and a multi-dimensional temperature measurement system, combined with nitrogen curtain and PID control, the problems of large temperature fluctuations and inaccurate temperature measurement in traditional sintering furnaces have been solved, achieving efficient densification and stable cooling of powder sintered products and improving product quality.
Patent Information
- Application Number
- CN202511103869.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-07
- Publication Date
- 2025-10-31
AI Technical Summary
Traditional sintering furnaces lack efficient heat insulation and isolation design in the pre-sintering and sintering zones, resulting in large temperature fluctuations, which affect the diffusion and densification of powder particles. Furthermore, the temperature measurement is not accurate enough, leading to uneven hardness and mechanical properties of the products.
The system employs composite isolation components and a multi-dimensional temperature measurement system. It uses a nitrogen curtain to isolate heat convection, combines K-type and B-type thermocouples with a PID controller to adjust the heating power, and achieves zone temperature control. It also ensures temperature stability through stepped cooling and hot air insulation slow cooling components.
It effectively reduces temperature fluctuations, improves powder particle diffusion and densification, reduces porosity, enhances product hardness and mechanical property consistency, and avoids internal stress generation.
Smart Images
Figure CN120861809A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of powder sintering technology, specifically to an intelligent temperature-controlled sintering furnace for powder sintering products. Background Technology
[0002] Metal powder sintering is a key process that uses high temperatures to diffuse and fuse metal powder particles to form products with specific mechanical properties. The material usually passes through a pre-sintering zone in the sintering equipment to remove impurities such as organic binders and lubricants from the billet, so as to avoid the generation of harmful gases at high temperatures that would affect the quality of the product. Then, it passes through the sintering zone to sinter the powder particles at high temperatures to achieve densification of the billet. Finally, natural cooling or forced air cooling is used to cool the sintered product from high temperature to room temperature to complete the sintering process.
[0003] Traditional sintering furnaces often separate the pre-sintering and sintering zones with simple partitions, lacking efficient heat insulation and isolation designs. The pre-sintering zone is easily affected by the high-temperature radiation and heat convection of the sintering zone, and the actual temperature is often higher than the set value. This causes the organic binder to volatilize at a rate far exceeding the process requirements, resulting in a large number of bubbles forming inside the blanks and increasing porosity. At the same time, the sintering zone experiences cooling due to the infiltration of low-temperature airflow from the pre-sintering zone, especially at the junction of the two zones, where temperature fluctuations are large, resulting in insufficient diffusion of powder particles and inadequate densification of the blanks. Traditional sintering furnaces often use single-point thermocouple temperature measurement, which can only reflect local temperatures and cannot capture the temperature distribution differences within the area. In the sintering zone, the temperature difference between the upper and lower surfaces is too large, resulting in uneven heating of the upper and lower surfaces of the material, inconsistent sintering degrees, and excessive deviations in the hardness of the products, as well as large dispersion in mechanical properties. Summary of the Invention
[0004] The purpose of this invention is to provide an intelligent temperature-controlled sintering furnace for powder sintering products, so as to solve the problems mentioned in the background art.
[0005] To achieve the above objectives, the present invention provides the following technical solution: an intelligent temperature-controlled sintering furnace for powder sintering products, comprising a symmetrically arranged base and a protective shell fixed on the base, a material preparation component at the inlet of the protective shell, a material pushing component on one side of the material preparation component, a material conveying component between the bases, a composite isolation component above the material conveying component, a multi-dimensional temperature measuring component on one side of the protective shell, and a cooling component at the outlet of the protective shell; The base is fixed with a side plate by screws, and the protective shell is fixed to the base by bolts. The interior of the protective shell includes a pre-firing zone, a sintering zone, and a cooling zone. The composite isolation assembly includes a nitrogen tank, a solenoid valve, an annular pipe, an isolation plate, a jet pipe, and pipe connectors. The nitrogen tank is located outside the protective shell. The nitrogen tank outlet pipe is connected to one end of the solenoid valve. The other end of the solenoid valve is connected to the annular pipe through the pipe connectors. The annular pipe is nested outside the isolation plate and locked to the isolation plate with screws. Furthermore, the isolation plate is made of mullite fiber, and the pipe connector includes a main pipe and branch pipes. The main pipes are provided in pairs and connected by pipes. The upper main pipe is fixed to the top of the protective shell with screws, and the lower main pipe is fixed to the plate between the side plates with screws.
[0006] Furthermore, the main pipe is connected to a solenoid valve on one side, the branch pipe is vertically arranged and connected between the main pipe and the annular pipe, and several jet pipes are provided and are equidistantly arranged on one side of the annular pipe.
[0007] Open the solenoid valve on the nitrogen tank, and nitrogen gas flows from the main pipe into the branch pipe, then into the annular pipe, and finally is sprayed from the jet pipe along the upper and lower directions towards the mesh belt in the middle, forming an air curtain between the pre-firing zone and the sintering zone, as well as between the sintering zone and the cooling zone. This blocks heat convection and airflow exchange, significantly reducing heat crosstalk between the zones. At the same time, the mullite fiber isolation plate has the characteristics of high temperature resistance and low thermal conductivity, providing good thermal insulation performance. It divides the zones, thereby avoiding the impact of high temperature on the pre-firing zone and low temperature on the sintering zone, thus improving the sintering quality.
[0008] Furthermore, the multidimensional temperature measurement component includes a K-type thermocouple, a B-type thermocouple, a quartz heating tube plate, a silicon molybdenum rod, and a PID control box. The K-type thermocouples are provided in two sets and are symmetrically arranged in the pre-burning area. The quartz heating tube plate is located outside the K-type thermocouples.
[0009] The pre-firing zone uses quartz heating tubes on a quartz heating tube sheet to heat the metal billet from both above and below. K-type hot spot couplers collect heating temperatures from above and below the metal billet in real time and feed them back to the PID control box to adjust the heating power of the quartz heating tube sheet, so as to avoid excessive temperature causing the binder to evaporate too quickly and the porosity to increase.
[0010] Furthermore, the type B thermocouples are provided in three sets and are symmetrically arranged in the sintering zone. The silicon molybdenum rods are arranged outside the type B thermocouples and correspond to them one by one. The PID control box is equipped with ten PID controllers and eight thyristor power controllers. The PID controllers are electrically connected to the thyristor power controllers.
[0011] Furthermore, the thyristor power controller is electrically connected to the quartz heating tube sheet and the silicon molybdenum rod, and the PID controller is electrically connected to the K-type thermocouple and the B-type thermocouple.
[0012] The silicon molybdenum rod is electrically heated to sinter the metal billet at high temperature. A type B hot electrode monitors the temperature from various areas above and below and provides real-time feedback to the PID controller. The PID controller compares the feedback temperature with the preset temperature and adjusts the heating power of the silicon molybdenum rod in a timely manner through the thyristor power controller to minimize heating fluctuations and ensure that the billet powder particles are fully diffused.
[0013] Furthermore, the material preparation assembly includes a belt conveyor, a storage platform on one side of the belt conveyor, the storage platform being located at the entrance of the protective shell, and a mesh material box being provided on both the belt conveyor and the storage platform, the mesh material box containing several metal billets.
[0014] Furthermore, the pushing assembly includes a hydraulic cylinder, one end of which is provided with a push rod. The hydraulic cylinder is connected to an electric valve via an oil pipe, and the electric valve is located on the oil tank.
[0015] The hollow bottom of the mesh material box allows the metal billet to be sintered from both the top and bottom. The belt conveyor carries the metal billet to be sintered and slides it onto the platform. Then, the electric valve is activated, and the hydraulic oil in the oil tank is drawn into the oil cylinder, causing the push rod to extend forward and push the mesh material box carrying the metal billet onto the mesh belt.
[0016] Furthermore, the material conveying assembly includes steel wheels symmetrically arranged at the inlet and outlet of the protective shell. The steel wheels have rotating shafts at both ends, and the rotating shafts are fitted with bearings and rotate in cooperation. The bearings are fixed to the base by screws. A mesh belt is nested on the outside of the steel wheel and rotates in cooperation. One end of the rotating shaft is connected to a reducer through a coupling, and the reducer is connected to a motor.
[0017] The motor uses a speed reducer to reduce the speed, thereby increasing the torque. It drives the steel wheel to rotate through the shaft, and the steel wheel uses a mesh belt to carry the metal billet into the pre-firing zone.
[0018] Furthermore, the cooling assembly includes a cooling fan, which is connected to the cooling zone through a fan shroud. A water chiller is provided on one side of the cooling fan, and the water chiller is connected to a pipe sleeve through a conduit. The pipe sleeve is located above the mesh belt.
[0019] The cooling fan blows out a high-speed airflow through the fan shroud. The airflow impacts the billet, causing the high-temperature billet to cool down rapidly. Then the billet enters the area below the tube sleeve, where the water chiller supplies cold water to the tube sleeve to absorb the heat emitted by the billet. Through two-stage cooling, the billet is cooled in a stepped manner to avoid the generation of internal stress.
[0020] Furthermore, a hot air insulation and slow cooling component is added to the cooling zone. The hot air insulation and slow cooling component includes a wind box, with fans symmetrically arranged on the inner wall of the wind box. A heating grid block is arranged on the opposite side of the fans. The heating grid block includes a conductive plate, with folded aluminum alloy heat sinks arranged between the conductive plates. PTC heating ceramics are arranged between the folded aluminum alloy heat sinks. An air outlet is provided on one side of the heating grid block, and the air outlet is connected to the cooling zone area before the ventilation hood.
[0021] The PTC heating ceramic is heated by a conductive plate, and the PTC heating ceramic dissipates heat through folded aluminum alloy heat sinks. When the fan rotates, the hot air is blown onto the metal billet, forming hot air insulation, slowing down the cooling rate, and gradually reducing the temperature gradient between the inside and outside of the workpiece to avoid instantaneous stress accumulation. The resistance of the PTC heating ceramic increases with the increase of temperature. When the heating temperature reaches the jump temperature, the resistance remains constant, thereby keeping the heat output constant and achieving automatic constant temperature, thus ensuring the stability of the hot air insulation of the billet.
[0022] Compared with the prior art, the present invention provides an intelligent temperature-controlled sintering furnace for powder sintering products, which has the following beneficial effects: 1. The intelligent temperature-controlled sintering furnace for this powder sintering product monitors the temperature of the pre-sintering zone and the sintering zone from the top and bottom and in each area using K-type and B-type thermocouples. Combined with the PID control box and thyristor power controller, the heating power is adjusted in real time to reduce temperature fluctuations. At the same time, the design of the isolation plate and air curtain blocks thermal crosstalk and avoids mutual influence between the two zones, ensuring that the binder volatilizes at a suitable rate during pre-sintering and that the powder can diffuse fully during sintering, thereby reducing porosity and improving the densification of the blank.
[0023] 2. The intelligent temperature-controlled sintering furnace for this powder sintering product adopts a two-stage stepped cooling system in the cooling zone. For thin-walled parts with holes, a hot air insulation cooling component is added to avoid internal stress or cracking caused by improper cooling rate, thereby reducing the dispersion of product hardness and mechanical properties. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the external structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the present invention; Figure 3 This is a schematic diagram of the composite isolation component structure of the present invention; Figure 4 This is a schematic diagram of the multidimensional temperature measurement component structure of the present invention; Figure 5 This is a schematic diagram of the PID control box structure of the present invention; Figure 6 This is a schematic diagram of the material preparation component structure of the present invention; Figure 7This is a schematic diagram of the feeding assembly structure of the present invention; Figure 8 This is a schematic diagram of the cooling component structure of the present invention; Figure 9 This is a schematic diagram of the hot air insulation and slow cooling component structure of the present invention; Figure 10 This is a schematic diagram of the heating mesh block structure of the present invention; Figure 11 This is a schematic diagram of the material conveying component structure of the present invention.
[0025] In the diagram: 1. Base; 2. Protective shell; 3. Material preparation assembly; 4. Pushing assembly; 5. Material conveying assembly; 6. Composite isolation assembly; 7. Multi-dimensional temperature measurement assembly; 8. Cooling assembly; 11. Side plate; 21. Pre-firing zone; 22. Sintering zone; 23. Cooling zone; 61. Nitrogen tank; 62. Solenoid valve; 63. Annular pipe; 64. Isolation plate; 65. Jet pipe; 71. Type K thermocouple; 72. Type B thermocouple; 73. Quartz heating tube sheet; 74. Silicon molybdenum rod; 75. PID control box; 751. PID controller; 752. Thyristor power controller; 66. Main pipe; 6 7. Pipe; 31. Belt conveyor; 32. Storage platform; 33. Grid material box; 34. Metal billet; 41. Hydraulic cylinder; 42. Push rod; 43. Electric valve; 44. Oil tank; 51. Steel wheel; 52. Shaft; 53. Bearing; 54. Mesh belt; 55. Reducer; 56. Motor; 81. Cooling fan; 82. Fan cover; 83. Water chiller; 84. Pipe sleeve; 9. Hot air insulation and slow cooling assembly; 91. Air box; 92. Fan; 93. Heating grid block; 931. Conductive plate; 932. Folded aluminum alloy heat sink; 933. PTC heating ceramic; 94. Air outlet. Detailed Implementation
[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1
[0027] Please see Figures 1-8 as well as Figure 11 A smart temperature-controlled sintering furnace for powder sintering products includes a symmetrically arranged base 1 and a protective shell 2 fixed on the base 1. A material preparation component 3 is provided at the inlet of the protective shell 2, a material pushing component 4 is provided on one side of the material preparation component 3, a material conveying component 5 is provided between the bases 1, a composite isolation component 6 is provided above the material conveying component 5, a multi-dimensional temperature measuring component 7 is provided on one side of the protective shell 2, and a cooling component 8 is provided at the outlet of the protective shell 2. A side plate 11 is fixed to the base 1 by screws, and a protective shell 2 is fixed to the base 1 by bolts. The interior of the protective shell 2 includes a pre-firing zone 21, a sintering zone 22, and a cooling zone 23. The composite isolation assembly 6 includes a nitrogen tank 61, a solenoid valve 62, an annular pipe 63, an isolation plate 64, a jet pipe 65, and pipe connectors. The nitrogen tank 61 is located outside the protective shell 2. The outlet pipe of the nitrogen tank 61 is connected to one end of the solenoid valve 62. The other end of the solenoid valve 62 is connected to the annular pipe 63 through the pipe connectors. The annular pipe 63 is nested outside the isolation plate 64 and locked to the isolation plate 64 by screws. Furthermore, the isolation plate 64 is made of mullite fiber, and the pipe connectors include a main pipe 66 and branch pipes 67. The main pipe 66 is provided in pairs and connected by pipes. The upper main pipe 66 is fixed to the top of the protective shell 2 by screws, and the lower main pipe 66 is fixed to the plate between the side plates 11 by screws.
[0028] Furthermore, the main pipe 66 is connected to the solenoid valve 62 on one side, the branch pipe 67 is vertically arranged and connected between the main pipe 66 and the annular pipe 63, and several jet pipes 65 are provided and are equidistantly arranged on one side of the annular pipe 63.
[0029] Open the solenoid valve 62 on the nitrogen tank 61, and nitrogen gas flows from the main pipe into the branch pipe 67, then into the annular pipe 63, and finally is sprayed from the jet pipe 65 along the upper and lower directions towards the mesh belt 54 in the middle, forming an air curtain between the pre-burning zone 21 and the sintering zone 22, and between the sintering zone 22 and the cooling zone 23. This blocks heat convection and airflow exchange, greatly reducing heat crosstalk between the areas. At the same time, the mullite fiber isolation plate 64 has the characteristics of high temperature resistance and low thermal conductivity, and has good heat insulation performance. It divides the areas, thereby avoiding the influence of high temperature on the pre-burning zone 21 and low temperature on the sintering zone 22, thus improving the sintering quality.
[0030] Furthermore, the multidimensional temperature measurement component 7 includes a K-type thermocouple 71, a B-type thermocouple 72, a quartz heating tube plate 73, a silicon molybdenum rod 74, and a PID control box 75. The K-type thermocouple 71 is provided in two sets and is symmetrically arranged in the pre-burning zone 21. The quartz heating tube plate 73 is located outside the K-type thermocouple 71.
[0031] The preheating zone 21 uses quartz heating tubes of quartz heating tube plate 73 to heat the metal billet 34 from both the top and bottom. K-type hot thermocouple 71 collects the heating temperature from the top and bottom of the metal billet in real time and feeds it back to the PID control box in a timely manner to adjust the heating power of quartz heating tube plate 73 to avoid excessive temperature causing the binder to evaporate too quickly and the porosity to increase.
[0032] Furthermore, three sets of type B thermocouples 72 are symmetrically arranged in the sintering zone 22. Silicon molybdenum rods 74 are arranged on the outside of type B thermocouples 72 and correspond to them one by one. The PID control box 75 contains ten PID controllers 751 and eight thyristor power controllers 752. The PID controllers 751 are electrically connected to the thyristor power controllers 752.
[0033] Furthermore, the thyristor power controller 752 is electrically connected to the quartz heating tube sheet 73 and the silicon molybdenum rod 74, and the PID controller 751 is electrically connected to the K-type thermocouple 71 and the B-type thermocouple 72.
[0034] The silicon molybdenum rod 74 is electrically heated to sinter the metal billet at high temperature. The type B hot thermocouple 72 monitors the temperature from various areas above and below and feeds it back to the PID controller 751 in real time. The PID controller 751 compares the feedback temperature with the preset temperature and adjusts the heating power of the silicon molybdenum rod 74 in a timely manner through the thyristor power controller 752 to minimize heating fluctuations and ensure that the billet powder particles are fully diffused.
[0035] Furthermore, the material preparation assembly 3 includes a belt conveyor 31, a storage platform 32 is provided on one side of the belt conveyor 31, the storage platform 32 is located at the entrance of the protective shell 2, and a grid material box 33 is provided on both the belt conveyor 31 and the storage platform 32, and a number of metal blanks 34 are provided in the grid material box 33.
[0036] Furthermore, the pushing assembly 4 includes a hydraulic cylinder 41, one end of which is provided with a push rod 42. The hydraulic cylinder 41 is connected to an electric valve 43 through an oil pipe, and the electric valve 43 is located on the oil tank 44.
[0037] The hollow bottom of the mesh material box 33 allows the metal billet 34 to be sintered from both the top and bottom. The belt conveyor 31 carries the metal billet 34 to be sintered and slides it onto the platform 32. Then, the electric valve 43 is activated, and the hydraulic oil in the oil tank 44 is drawn into the oil cylinder 41, causing the push rod 42 to extend forward, thereby pushing the mesh material box 33 carrying the metal billet 34 onto the mesh belt 54.
[0038] Furthermore, the material conveying assembly 5 includes a steel wheel 51, which is symmetrically arranged at the inlet and outlet of the protective shell 2. The steel wheel 51 has a rotating shaft 52 at both ends, and the rotating shaft 52 is fitted with a bearing 53 and rotates in cooperation. The bearing 53 is fixed to the base 1 by screws. A mesh belt 54 is nested on the outside of the steel wheel 51 and rotates in cooperation. One end of the rotating shaft 52 is connected to a reducer 55 through a coupling, and the reducer 55 is connected to a motor 56.
[0039] The motor 56 uses the reducer 55 to reduce the speed, thereby increasing the torque. It drives the steel wheel 51 to rotate through the shaft 52. The steel wheel 51 uses the mesh belt 54 to carry the metal billet 34 into the pre-firing zone 21.
[0040] Furthermore, the cooling assembly 8 includes a cooling fan 81, which is connected to the cooling zone 23 through a fan shroud 82. A water chiller 83 is provided on one side of the cooling fan 81, and the water chiller 83 is connected to a pipe sleeve 84 through a conduit. The pipe sleeve 84 is located above the mesh belt 54.
[0041] Cooling fan 81 blows out high-speed airflow through fan shroud 82. The airflow impacts the billet, causing the high-temperature billet to cool down rapidly. Then the billet enters the area below the sleeve 84. Water chiller 83 introduces cold water into sleeve 84 to absorb the heat emitted by the billet. Through two-stage cooling, the billet is cooled in a stepped manner to avoid the generation of internal stress. Example 2
[0042] Please see Figure 9 , Figure 10 The difference between Embodiment 2 and Embodiment 1 is that: a hot air heat preservation and slow cooling component 9 is added to the cooling zone 23. The hot air heat preservation and slow cooling component 9 includes a wind box 91. Fans 92 are symmetrically arranged on the inner wall of the wind box 91. A heating grid block 93 is arranged on the opposite side of the fan 92. The heating grid block 93 includes a conductive plate 931. Folded aluminum alloy heat sinks 932 are arranged between the conductive plates 931. PTC heating ceramics 933 are arranged between the folded aluminum alloy heat sinks 932. An air outlet 94 is arranged on one side of the heating grid block 93. The air outlet 94 is connected to the cooling zone 23 area before the ventilation hood 82.
[0043] Because the structure of a perforated thin-walled part is thin, its heat dissipation rate is much faster than that of a thick-walled part. However, there are structural abrupt changes at the edge of the hole, resulting in uneven heat distribution during cooling and easy formation of local temperature differences. If the part is directly cooled by rapid air cooling from a high temperature, the large difference in cooling rate between the inside and outside will generate huge thermal stress, causing the workpiece to crack or deform. The PTC heating ceramic 933 is heated by the conductive plate 931. The PTC heating ceramic 933 dissipates heat through the folded aluminum alloy heat sink 932. When the fan 92 rotates, the hot air is blown towards the metal blank 34 to form hot air insulation, slow down the cooling rate, and gradually reduce the temperature gradient between the inside and outside of the workpiece, avoiding the instantaneous accumulation of stress. The resistance of the PTC heating ceramic 933 increases with the increase of temperature. When the heating temperature reaches the jump temperature, the resistance remains constant, thereby keeping the heat generation constant and achieving automatic constant temperature, thus ensuring the stability of the hot air insulation of the blank.
[0044] The specific usage and function of this embodiment are as follows: In use, the metal billet 34 is first placed in the high-temperature resistant mesh material box 33. The hollow bottom of the mesh material box 33 allows the metal billet 34 to be sintered from both the top and bottom. The belt conveyor 31 carries the metal billet 34 to be sintered and slides it onto the platform 32. Then, the electric valve 43 is activated, and the hydraulic oil in the oil tank 44 is drawn into the oil cylinder 41, causing the push rod 42 to extend forward, thereby pushing the mesh material box 33 carrying the metal billet 34 onto the mesh belt 54. Then, the motor 56 is started. The motor 56 uses the reducer 55 to reduce the speed, thereby increasing the torque. The rotating shaft 52 drives the steel wheel 51 to rotate. The steel wheel 51 uses the mesh belt 54 to carry the metal billet 34 into the pre-firing zone 21. The pre-firing zone 21 uses the quartz heating tubes of the quartz heating tube plate 73 to heat the metal billet 34 from both the top and bottom. The K-type hot electrode 71 collects the heating temperature from the top and bottom of the metal billet in real time and feeds it back to the PID control box in a timely manner to adjust the heating power of the quartz heating tube plate 73 to avoid the binder from evaporating too quickly due to excessive temperature and increasing the porosity. Subsequently, the metal billet enters the sintering zone 22 from the pre-sintering zone 21. The silicon molybdenum rod 74 is electrically heated to sinter the metal billet by emitting high temperature. The type B hot electrode 72 monitors the temperature from the top and bottom areas and feeds it back to the PID controller 751 in real time. The PID controller 751 compares the feedback temperature with the preset temperature and adjusts the heating power of the silicon molybdenum rod 74 in a timely manner through the thyristor power controller 752 to minimize heating fluctuations and ensure that the billet powder particles are fully diffused. During pre-firing and sintering, the solenoid valve 62 on the nitrogen tank 61 is opened, and nitrogen gas is introduced from the main pipe into the branch pipe 67, then into the annular pipe 63, and finally sprayed from the jet pipe 65 along the upper and lower directions towards the mesh belt 54 in the middle, forming an air curtain between the pre-firing zone 21 and the sintering zone 22, and between the sintering zone 22 and the cooling zone 23, blocking heat convection and air exchange, and greatly reducing heat crosstalk between the areas. At the same time, the mullite fiber isolation plate 64 has the characteristics of high temperature resistance and low thermal conductivity, and has good heat insulation performance, dividing the areas, thereby avoiding the influence of high temperature on the pre-firing zone 21 and low temperature on the sintering zone 22, and improving the sintering quality. After sintering, the metal billet 34 enters the cooling zone along the mesh belt 54. First, the cooling fan 81 blows out a high-speed airflow through the fan shroud 82. The airflow impacts the billet, causing the high-temperature billet to cool down rapidly. Then, the billet enters the area below the sleeve 84. The water chiller 83 introduces cold water into the sleeve 84 to absorb the heat emitted by the billet. The billet is cooled in a stepped manner through two-stage cooling to avoid the generation of internal stress. When the sintered metal billet is a thin-walled part with holes, a hot air insulation and slow cooling component 9 is added to the cooling zone 23. Because the thin-walled part with holes has a small structural thickness, its heat dissipation speed is much faster than that of a thick-walled part. However, there is a structural abrupt change at the edge of the hole, and the heat distribution is uneven during cooling, which can easily form local temperature differences. If the workpiece is directly cooled by high-temperature rapid air, the large difference in cooling rate between the inside and outside will generate huge thermal stress, causing the workpiece to crack or deform. The PTC heating ceramic 933 is heated by the conductive plate 931. The PTC heating ceramic 933 dissipates heat through the folded aluminum alloy heat sink 932. When the fan 92 rotates, the hot air is blown towards the metal billet 34 to form hot air insulation, slow down the cooling rate, and gradually reduce the temperature gradient between the inside and outside of the workpiece, avoiding the instantaneous accumulation of stress. The resistance of the PTC heating ceramic 933 will increase with the increase of temperature. When the heating temperature reaches the jump temperature, the resistance remains constant, so that the heat generation remains constant and automatic constant temperature is achieved, thereby ensuring the stability of the hot air insulation of the billet.
[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. An intelligent temperature-controlled sintering furnace for powder sintering products, comprising a symmetrically arranged base (1) and a protective shell (2) fixed on the base (1), characterized in that: The protective shell (2) is provided with a material preparation component (3) at the inlet, a material pushing component (4) is provided on one side of the material preparation component (3), a material conveying component (5) is provided between the bases (1), a composite isolation component (6) is provided above the material conveying component (5), a multi-dimensional temperature measuring component (7) is provided on one side of the protective shell (2), and a cooling component (8) is provided at the outlet of the protective shell (2). The base (1) is fixed with a side plate (11) by screws, and the protective shell (2) is fixed to the base (1) by bolts. The protective shell (2) includes a pre-burning zone (21), a sintering zone (22) and a cooling zone (23). The composite isolation assembly (6) includes a nitrogen tank (61), a solenoid valve (62), an annular pipe (63), an isolation plate (64), a jet pipe (65), and pipe connectors. The nitrogen tank (61) is located outside the protective shell (2). The outlet pipe of the nitrogen tank (61) is connected to one end of the solenoid valve (62). The other end of the solenoid valve (62) is connected to the annular pipe (63) through the pipe connectors. The annular pipe (63) is nested outside the isolation plate (64) and locked to the isolation plate (64) by screws. The multidimensional temperature measurement component (7) includes a K-type thermocouple (71), a B-type thermocouple (72), a quartz heating tube plate (73), a silicon molybdenum rod (74), and a PID control box (75). The K-type thermocouple (71) is provided in two sets and is symmetrically arranged in the pre-burning zone (21). The quartz heating tube plate (73) is located outside the K-type thermocouple (71).
2. The intelligent temperature-controlled sintering furnace for powder sintering products according to claim 1, characterized in that: The type B thermocouple (72) is provided in three sets and is symmetrically arranged in the sintering zone (22). The silicon molybdenum rod (74) is located outside the type B thermocouple (72) and is arranged in a one-to-one correspondence with it. The PID control box (75) is provided with ten PID controllers (751) and eight thyristor power controllers (752). The PID controllers (751) are electrically connected to the thyristor power controllers (752).
3. The intelligent temperature-controlled sintering furnace for powder sintering products according to claim 2, characterized in that: The thyristor power controller (752) is electrically connected to the quartz heating tube sheet (73) and the silicon molybdenum rod (74), and the PID controller (751) is electrically connected to the K-type thermocouple (71) and the B-type thermocouple (72).
4. The intelligent temperature-controlled sintering furnace for powder sintering products according to claim 3, characterized in that: The isolation plate (64) is made of mullite fiber. The pipe connector includes a main pipe (66) and a branch pipe (67). The main pipe (66) is provided in pairs and connected by pipes. The upper main pipe (66) is fixed to the top of the protective shell (2) by screws, and the lower main pipe (66) is fixed to the plate between the side plates (11) by screws.
5. The intelligent temperature-controlled sintering furnace for powder sintering products according to claim 4, characterized in that: The main pipe (66) is connected to a solenoid valve (62) on one side. The branch pipe (67) is vertically arranged and connected between the main pipe (66) and the annular pipe (63). The jet pipe (65) is provided in several equidistant arrangement on one side of the annular pipe (63).
6. The intelligent temperature-controlled sintering furnace for powder sintering products according to claim 1, characterized in that: The material preparation component (3) includes a belt conveyor (31), a storage platform (32) is provided on one side of the belt conveyor (31), the storage platform (32) is located at the entrance of the protective shell (2), and a grid material box (33) is provided on both the belt conveyor (31) and the storage platform (32), and a number of metal blanks (34) are provided in the grid material box (33).
7. The intelligent temperature-controlled sintering furnace for powder sintering products according to claim 1, characterized in that: The pushing assembly (4) includes a hydraulic cylinder (41), one end of which is provided with a push rod (42). The hydraulic cylinder (41) is connected to an electric valve (43) via an oil pipe. The electric valve (43) is located on the oil tank (44).
8. The intelligent temperature-controlled sintering furnace for powder sintering products according to claim 1, characterized in that: The material conveying assembly (5) includes a steel wheel (51), which is symmetrically arranged at the inlet and outlet of the protective shell (2). The steel wheel (51) has a rotating shaft (52) at both ends. The rotating shaft (52) is fitted with a bearing (53) and rotates in cooperation. The bearing (53) is fixed to the base (1) by screws. The steel wheel (51) is nested with a mesh belt (54) and rotates in cooperation. One end of the rotating shaft (52) is connected to a reducer (55) through a coupling. The reducer (55) is connected to a motor (56).
9. The intelligent temperature-controlled sintering furnace for powder sintering products according to claim 1, characterized in that: The cooling assembly (8) includes a cooling fan (81), which is connected to the cooling zone (23) through a fan shroud (82). A water chiller (83) is provided on one side of the cooling fan (81), and the water chiller (83) is connected to a pipe sleeve (84) through a conduit. The pipe sleeve (84) is located above the mesh belt (54).
10. The intelligent temperature-controlled sintering furnace for powder sintering products according to claim 1, characterized in that: The cooling zone (23) is equipped with a hot air insulation and slow cooling component (9). The hot air insulation and slow cooling component (9) includes a wind box (91). The inner wall of the wind box (91) is symmetrically provided with fans (92). The opposite side of the fans (92) is provided with a heating grid block (93). The heating grid block (93) includes a conductive plate (931). Folded aluminum alloy heat sinks (932) are provided between the conductive plates (931). PTC heating ceramics (933) are provided between the folded aluminum alloy heat sinks (932). An air outlet (94) is provided on one side of the heating grid block (93). The air outlet (94) is connected to the cooling zone (23) area before the ventilation hood (82).