Annular furnace heat treatment production line with intercooling and secondary heating functions

Abstract

An annular furnace heat treatment production line with intercooling and secondary heating functions comprises a feeding table, a pre-oxidation furnace, a heating furnace, a push plate diffusion furnace, an annular carburizing furnace, a double-station intercooling chamber, a rotary hearth type secondary heating furnace, an oil quenching tank, a cleaning machine and a discharging table which are sequentially connected. Wherein the interior of the double-station intercooling chamber is divided into a left cooling chamber, a right cooling chamber and a public channel, and a diffusion furnace discharging mechanism of the push disc diffusion furnace can selectively push workpieces subjected to diffusion treatment into the public channel or the rotary hearth type secondary heating furnace; when the workpieces are pushed to the public channel, the workpieces are subjected to intercooling and secondary heating treatment in sequence through the left cooling chamber, the right cooling chamber and the rotary hearth type secondary heating furnace, and then the workpieces are fed into an oil quenching tank; and when the workpiece is directly pushed into the rotary hearth type secondary heating furnace, the workpiece can be fed into the oil quenching tank through the rotary hearth type secondary heating furnace. Therefore, the heat treatment requirements of different types of workpieces can be met, and the heat treatment efficiency of the workpieces can be improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to workpiece heat treatment technical field especially is related to a kind of annular furnace heat treatment production line with middle cooling, secondary heating function. BACKGROUND

[0002] At present, the main process steps implemented by annular furnace heat treatment production line are mostly heating, carburizing, diffusion, holding, quenching or pressure quenching steps, and for the workpiece made of special metal material, middle cooling and secondary heating process steps are usually needed in the heat treatment process, however, if the existing annular furnace heat treatment production line wants to implement the middle cooling and secondary heating process steps, it can only move the workpiece out of the annular furnace heat treatment production line after completing the diffusion step and transfer it to the middle cooling and secondary heating equipment to implement the related process steps, which leads to the discrete configuration of production equipment, and additional auxiliary transfer equipment such as workpiece holding transfer carrier is needed for auxiliary operation, and the whole heat treatment process cannot be implemented continuously, which not only increases the labor and material input cost, but also makes the workpiece heat treatment efficiency relatively low. Therefore, how to orderly integrate the middle cooling and secondary heating process into the annular furnace heat treatment production line to improve the integration level of the whole production line, and make the heat treatment process be orderly and continuously implemented, and also meet the different heat treatment needs of ordinary workpieces and special metal workpieces at the same time, so as to save the labor and material input cost and improve the workpiece heat treatment efficiency, has become one of the technical problems to be solved in the field. SUMMARY

[0003] The technical problem to be solved by the present technical solution is how to orderly integrate the middle cooling and secondary heating process equipment into the annular furnace heat treatment production line, so that the annular furnace heat treatment production line can not only meet the different heat treatment needs of ordinary workpieces and special metal workpieces at the same time, but also make the heat treatment process be orderly and continuously implemented, so as to save the labor and material input cost and improve the workpiece heat treatment efficiency.

[0004] To solve the above technical problems, the technical scheme provides a ring furnace heat treatment production line with the functions of intercooling and secondary heating, which is used for selectively performing carburizing, intercooling, secondary heating and quenching operations or performing carburizing and quenching operations on workpieces contained in trays, and comprises a feeding table, a pre-oxidation furnace, a heating furnace, a tray pushing diffusion furnace, a ring carburizing furnace, a double-station intercooling chamber, a rotary hearth secondary heating furnace, a quenching oil tank, a cleaning machine and a discharging table. The feeding table is connected with an inlet of the pre-oxidation furnace, an outlet of the pre-oxidation furnace is connected with a bottom loading section of the heating furnace through a lifting loading mechanism, two opposite side walls of an inlet end of the tray pushing diffusion furnace are respectively provided with a heating inlet and a carburizing inlet which are aligned with each other, an outlet of the heating furnace is sealingly connected with the heating inlet, an inlet and an outlet of the ring carburizing furnace are sealingly connected with the carburizing inlet, the inside of the double-station intercooling chamber is sequentially divided into a left cooling chamber, a common passage and a right cooling chamber from one side to the other side, and two opposite side walls at both ends of the common passage of the double-station intercooling chamber are respectively provided with an intercooling chamber inlet and an intercooling chamber outlet which are communicated with the common passage, one side wall of an outlet end of the tray pushing diffusion furnace is provided with a diffusion outlet, the intercooling chamber inlet is sealingly connected with the diffusion outlet, a secondary heating inlet of the rotary hearth secondary heating furnace is sealingly connected with the intercooling chamber outlet, a secondary heating outlet of the rotary hearth secondary heating furnace is sealingly connected with an inlet of the quenching oil tank, an outlet of the quenching oil tank is connected with an inlet of the cleaning machine, and an outlet of the cleaning machine is connected with the discharging table. During operation, according to the heat treatment requirements of different types of workpieces, a diffusion furnace outlet mechanism of the tray pushing diffusion furnace can selectively push the workpieces after carburizing diffusion treatment to the common passage or directly push them into the rotary hearth secondary heating furnace, wherein when the workpieces are pushed by the diffusion furnace outlet mechanism to the common passage, the workpieces are moved into the left cooling chamber or the right cooling chamber for intercooling treatment, then the workpieces after intercooling treatment are pushed by the diffusion furnace outlet mechanism into the rotary hearth secondary heating furnace for secondary heating treatment, and then the workpieces after secondary heating treatment are sent into the quenching oil tank for quenching treatment, and when the workpieces are directly pushed by the diffusion furnace outlet mechanism into the rotary hearth secondary heating furnace, the workpieces are sent into the quenching oil tank for quenching treatment through the rotary hearth secondary heating furnace. Accordingly, the double-station intercooling chamber and the rotary hearth secondary heating furnace are sequentially added between the tray pushing diffusion furnace and the quenching oil tank of the ring furnace heat treatment production line, and the diffusion furnace outlet mechanism of the tray pushing diffusion furnace can selectively push the workpieces to the common passage or directly push them into the rotary hearth secondary heating furnace according to the heat treatment requirements of different types of workpieces, so as to selectively implement intercooling, secondary heating and quenching treatment or directly implement quenching treatment on the workpieces after diffusion treatment. In addition, since the double-station intercooling chamber has left and right cooling chambers, it can simultaneously perform intercooling operations on two workpieces, and the rotary hearth secondary heating furnace can also simultaneously perform secondary heating operations on multiple workpieces, so that the ring furnace heat treatment production line has a continuous heat treatment capacity like an assembly line and has a high heat treatment efficiency.

[0005] As another implementation of the present technical solution, the double-station intermediate cooling chamber is mainly composed of an intermediate cooling chamber shell, an intermediate cooling chamber lining, a pair of common passage guide rails, two pairs of intermediate cooling chamber guide rails, two push-pull material mechanisms, two high-temperature fans, two air guide muffs, two lifting air guide doors, two heat exchange mechanisms, two protective atmosphere gas supply pipelines, and a waste gas discharge pipeline. The intermediate cooling chamber shell is wrapped outside the intermediate cooling chamber lining. The interior of the intermediate cooling chamber lining is sequentially divided into the left cooling chamber, the common passage, and the right cooling chamber from one side to the other. The intermediate cooling chamber shell and the intermediate cooling chamber lining combine to form the furnace body structure of the double-station intermediate cooling chamber, and the two opposite sides thereof are respectively provided with an intermediate cooling chamber inlet and an intermediate cooling chamber outlet that communicate with the common passage. The pair of common passage guide rails are fixedly laid on the bottom of the common passage in the direction from the intermediate cooling chamber inlet to the intermediate cooling chamber outlet. The two pairs of intermediate cooling chamber guide rails are fixedly laid on the bottom of the left cooling chamber and the right cooling chamber, respectively, perpendicular to the pair of common passage guide rails. The two push-pull material mechanisms are fixedly installed outside the other two opposite side walls perpendicular to the side wall where the intermediate cooling chamber inlet is provided. The other two opposite side walls are respectively provided with material head through openings corresponding to the positions of the push-pull material heads of the two push-pull material mechanisms to allow the push-pull material heads to enter and exit. The two high-temperature fans are installed on the top of the left cooling chamber and the right cooling chamber, respectively. The two air guide muffs are respectively covered on the intermediate cooling chamber guide rails of the left cooling chamber and the right cooling chamber and communicate with the high-temperature fans. The two air guide muffs are respectively provided with inlets and outlets on the side facing the common passage. The two lifting air guide doors are respectively arranged at the inlets and outlets of the two air guide muffs. The two heat exchange mechanisms are respectively arranged on the two sides of the air guide muffs in the left cooling chamber and the right cooling chamber. The two protective atmosphere gas supply pipelines are respectively arranged outside the top of the left cooling chamber and the right cooling chamber and communicate with the interiors of the left cooling chamber and the right cooling chamber. The waste gas discharge pipeline is arranged outside the top of the common passage near the intermediate cooling chamber inlet and communicates with the interior of the common passage. The push-pull material heads of the push-pull material mechanisms are used to pull the workpieces placed on the common passage guide rails into the left cooling chamber or the right cooling chamber to perform intermediate cooling treatment on the workpieces. Then, the push-pull material heads are used to push the workpieces back to the common passage guide rails to complete the intermediate cooling treatment of the workpieces.

[0006] As another implementation of the technical solution, the heat exchange mechanism is mainly composed of two groups of heat exchange coils, two groups of heat exchange fins and a heat exchange medium driving device. The two groups of heat exchange coils are respectively fixedly arranged in the space between the two sides of the air guide muffle and the two side walls of the middle cold chamber lining. The medium inflow end and the medium outflow end of the heat exchange coil both pass through the top of the double-station middle cold chamber. The two groups of heat exchange fins are respectively arranged on the two groups of heat exchange coils. The heat exchange medium driving device is arranged outside the double-station middle cold chamber. When the heat exchange medium is external air, the heat exchange medium driving device is an air extractor, and the medium outflow end is connected with the suction end of the air extractor, and the medium inflow end is communicated with the external environment. In addition, when the heat exchange medium is cooling oil, the heat exchange medium driving device is composed of an oil supplement tank and a circulating oil pump connected with each other. The medium inflow end is connected with the pump outlet of the circulating oil pump, and the medium outflow end is connected with the oil supplement tank. Accordingly, the heat exchange mechanism can cool and cool the workpiece in the cooling chamber by air cooling and oil cooling.

[0007] As another implementation of the technical solution, the rotary hearth secondary heating furnace is mainly composed of a secondary heating furnace shell, a secondary heating furnace lining, a circular rotary hearth, a plurality of tray supports, a rotary hearth driving device, a plurality of radiant heating pipes, a plurality of high-temperature fans, a protective atmosphere gas supply pipeline, a waste gas discharge pipeline, an observation window and a maintenance door. The secondary heating furnace shell is wrapped outside the secondary heating furnace lining to combine to form the furnace body structure of the rotary hearth secondary heating furnace. The inside of the secondary heating furnace lining forms a circular furnace cavity. Two opposite sides of the rotary hearth secondary heating furnace body structure are respectively provided with a secondary heating inlet and a secondary heating outlet communicated with the circular furnace cavity. The circular rotary hearth is arranged on the bottom of the circular furnace cavity. The plurality of tray supports are arranged on the upper side of the circular rotary hearth in a spaced and uniform manner. The rotary hearth driving device is arranged below the circular rotary hearth and is drivingly connected with the circular rotary hearth to drive the circular rotary hearth to rotate circumferentially. The plurality of radiant heating pipes are uniformly arranged in the circular furnace cavity. The plurality of high-temperature fans are uniformly arranged on the upper part of the circular furnace cavity. The protective atmosphere gas supply pipeline is arranged outside the top of the circular furnace cavity and is communicated with the inside of the circular furnace cavity. The waste gas discharge pipeline is arranged outside the top of the circular furnace cavity near the secondary heating inlet and is communicated with the inside of the circular furnace cavity. The observation window and the maintenance door are arranged on the furnace body structure of the rotary hearth secondary heating furnace and are communicated with the inside of the circular furnace cavity.

[0008] As another implementation of the technical solution, the heating furnace is composed of a bottom charging section and a sealed heating section connected in a sealed manner. The discharge port of the pre-oxidation furnace is arranged at a lower height than the bottom charging section. The bottom of the bottom charging section is provided with a bottom charging port and a fire curtain. The lifting charging mechanism is arranged below the bottom charging port and is aligned with the discharge port of the pre-oxidation furnace. The workpiece after pre-oxidation treatment is moved into the lifting charging mechanism through the discharge port of the pre-oxidation furnace, and then the lifting charging mechanism lifts the workpiece to move it into the bottom charging section through the bottom charging port, and then the workpiece is moved into the sealed heating section for heating treatment. In this way, the bottom charging structure of the heating furnace and the arrangement of the fire curtain can effectively prevent external air from entering during the charging stage, thereby eliminating the occurrence of safety risks such as deflagration and explosion.

[0009] As another implementation of the technical solution, the pre-oxidation furnace is provided with lifting furnace doors at the inlet and outlet. The bottom charging section and the sealed heating section, the discharge port and the inlet of the heating furnace, the inlet and outlet, the carburizing inlet, the diffusion discharge port and the inlet of the medium cooling chamber, the outlet of the medium cooling chamber and the secondary heating inlet, and the inlet of the quenching oil tank are all provided with sealed lifting furnace doors. In this way, the heating and insulation of the pre-oxidation furnace are ensured, and the process safety operation of the heating furnace, the push disc diffusion furnace, the ring carburizing furnace, the double-station medium cooling chamber and the rotary hearth secondary heating furnace in a protective atmosphere environment is ensured.

[0010] As another implementation of the technical solution, the end of the loading table opposite the pre-oxidation furnace inlet, the outer side of the furnace wall of the pre-oxidation furnace opposite the discharge port, the outer side of the furnace wall of the bottom charging section opposite the sealed heating section, and the outer side of the furnace wall of the push disc diffusion furnace opposite the inlet are all provided with a guide rod pushing device composed of a pressure driven cylinder and a push rod. The discharge device provided on the outer side of the furnace wall of the heating furnace opposite the discharge port and the discharge mechanism of the diffusion furnace are both guide chain pushing devices composed of a coil chain track, a chain, a push head, a driving motor and a sprocket. The inner ring side of the furnace wall of the ring carburizing furnace opposite the inlet and outlet and the outer side of the quenching oil tank opposite the inlet are both provided with a workpiece supporting device. In this way, the workpiece transfer device is used to push and transfer the workpiece between the entire production line and each process equipment.

[0011] As another implementation of the technical solution, the ring furnace heat treatment production line further comprises a tempering furnace and an air cooling table connected in sequence between the cleaning machine and the discharge table. In this way, the ring furnace heat treatment production line is provided with tempering and air cooling process links.

[0012] As another implementation of the technical solution, the cleaning machine is composed of an alkali water soaking station, a water spraying station and a drying station arranged in sequence. In this way, the workpiece after quenching treatment can be thoroughly cleaned. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 It is the overhead view schematic diagram of the annular furnace heat treatment production line with the middle cooling and secondary heating functions of the utility model;

[0014] Figure 2 It is the overhead view schematic diagram of the double-station middle cooling chamber and the rotary hearth secondary heating furnace sealed connection in the utility model;

[0015] Figure 3 It is the side sectional view of the push-disc diffusion furnace, double-station middle cooling chamber, rotary hearth secondary heating furnace and quenching oil tank sealed connection in the utility model;

[0016] Figure 4a It is the structure schematic diagram of the push-pull material head for the push-pull operation of the material disc bottom;

[0017] Figure 4b It is the structure schematic diagram of the push-pull material head for the push-pull operation of the material disc rim;

[0018] Figure 5 It is the side sectional view of the bottom charging section of the heating furnace in the utility model;

[0019] Figure 6 It is the side sectional view of the workpiece supporting device in the utility model;

[0020] Figure 7 It is the side sectional view of the quenching oil tank in the utility model.

[0021] Explanation of symbols in the drawings:

[0022] 1. Loading platform; 2. Pre-oxidation furnace; 3. Heating furnace; 31. Bottom loading section; 311. Bottom loading port; 32. Sealed heating section; 33. Lifting loading mechanism; 4. Pusher plate diffusion furnace; 5. Annular carburizing furnace; 6. Dual-station intercooler chamber; 611. Intercooler chamber shell; 612. Intercooler chamber lining; 621. Left cooling chamber; 622. Common passage; 623. Right cooling chamber; 624. Common passage guide rail; 625. Intercooler chamber guide rail; 63. Push-pull material mechanism; 631. Push-pull material head; 64. High-temperature fan; 65. Air guide muffle; 66. Lifting air guide door; 67. Heat exchange mechanism; 7. Rotary bottom secondary heating furnace; 711. Secondary heating furnace shell; 712. Secondary heating furnace lining; 72. Circular rotary bottom; 73. Material tray support; 74. Radiant heating tube; 75. High-temperature fan; 76. Observation window; 77. 8 Inspection door; 8 Quenching oil tank; 81 Sealed front chamber; 82 Discharge chamber; 83 Quenching oil pool; 84 Workpiece quenching moving mechanism; 9 Cleaning machine; 10 Discharge platform; 11 Tempering furnace; 12 Air cooling platform; 13 Lifting furnace door; 14 Sealed lifting furnace door; 15 Guide rod pushing device; 16 Guide chain pushing device; 17 Workpiece supporting device; 171 Supporting mechanism housing; 172 Opening; 173 Pushing drive motor; 174 Screw; 175 Fork seat; 176 Fork; 177 Supporting link; 178 Lifting drive motor; 179 Eccentric cam; A Workpiece; B Material tray. Detailed Implementation

[0023] The detailed description and technical content of this utility model are explained below with reference to the accompanying drawings. However, the accompanying drawings are provided for reference and illustration only and are not intended to limit this utility model.

[0024] In the context of this specification, any two or more embodiments of this utility model can be arbitrarily combined, and the resulting technical solutions are part of the original disclosure of this specification and also fall within the protection scope of this utility model.

[0025] like Figure 1 The diagram shown is a schematic representation of a specific embodiment of the annular furnace heat treatment production line with intercooling and secondary heating functions of this utility model. This annular furnace heat treatment production line (hereinafter referred to as the annular furnace heat treatment production line) is used to selectively perform carburizing, intercooling, secondary heating, and quenching operations, or carburizing and quenching operations, on workpieces placed in a tray. The annular furnace heat treatment production line includes a loading platform 1, a pre-oxidation furnace 2, a heating furnace 3, a pusher diffusion furnace 4, an annular carburizing furnace 5, a dual-station intercooling chamber 6, a rotary hearth secondary heating furnace 7, a quenching oil tank 8, a cleaning machine 9, and a discharge platform 10. The loading platform 1 is connected to the inlet of the pre-oxidation furnace 2, and the outlet of the pre-oxidation furnace 2 is connected to the bottom loading section 31 of the heating furnace 3 via a lifting loading mechanism 33 (in conjunction with...).Figure 5 As shown in the figure, two opposite side walls of the feeding end of the pusher-diffusion furnace 4 are respectively provided with a heating feeding port and a carburizing feeding port which are aligned with each other, the discharging port of the heating furnace 3 is sealingly connected with the heating feeding port, and the inlet and outlet ports of the annular carburizing furnace 5 are sealingly connected with the carburizing feeding port. In combination Figure 2As shown, the inside of the double-station intercooler 6 is sequentially divided into a left cooling chamber 621, a common passage 622 and a right cooling chamber 623 from one side to the other side, and the double-station intercooler 6 is provided with an intercooler inlet and an intercooler outlet on two opposite side walls at both ends of the common passage 622 respectively, the intercooler inlet is in sealing connection with the diffusion discharge port, the secondary heating inlet of the rotary hearth secondary heating furnace 7 is in sealing connection with the intercooler outlet, the secondary heating discharge port of the rotary hearth secondary heating furnace 7 is in sealing connection with the inlet of the quenching oil tank 8, the discharge port of the quenching oil tank 8 is connected with the inlet of the cleaning machine 9, and the discharge port of the cleaning machine 9 is connected with the discharge table 10. The above constitutes each device of the annular furnace heat treatment production line of the utility model, the feeding table 1, the pre-oxidation furnace 2, the heating furnace 3, the push disc diffusion furnace 4, the annular carburizing furnace 5, the rotary hearth secondary heating furnace 7, the quenching oil tank 8, the cleaning machine 9 and the discharge table 10 are all devices commonly used in the existing workpiece heat treatment production line, wherein the heating furnace 3, the push disc diffusion furnace 4, the annular carburizing furnace 5, the rotary hearth secondary heating furnace 7 and the quenching oil tank 8 are all operated in a closed environment isolated from the outside and filled with a protective gas atmosphere (usually filled with nitrogen) to implement corresponding processes. The rotary hearth secondary heating furnace 7 is a kind of existing heating furnace, which is commonly used as a heating furnace in other existing heat treatment production lines, but is used for secondary heating of workpieces in the utility model. The biggest difference between the annular furnace heat treatment production line of the utility model and other existing workpiece heat treatment production lines is that the rotary hearth heating furnace is used as a secondary heating furnace, and a double-station intercooler 6 with a unique structure is arranged between the push disc diffusion furnace 4 and the rotary hearth secondary heating furnace 7, and the diffusion treated workpiece A is selectively pushed into the double-station intercooler 6 or the rotary hearth secondary heating furnace 7 by the diffusion furnace discharge mechanism of the push disc diffusion furnace 4, so as to realize different process treatment for different types of workpieces A, and because the double-station intercooler 6 and the rotary hearth secondary heating furnace 7 can simultaneously implement process treatment on multiple workpieces A, the heat treatment efficiency of the annular furnace heat treatment production line of the utility model can be greatly improved.Accordingly, the annular furnace heat treatment production line constituted by the above-mentioned equipment can selectively push the workpiece A after carburizing diffusion treatment to the common passage 622 or directly push it into the rotary hearth secondary heating furnace 7 according to the heat treatment requirements of different types of workpiece A by the diffusion furnace discharge mechanism of the push disc diffusion furnace 4. When the workpiece A is pushed onto the common passage 622 by the diffusion furnace discharge mechanism, the workpiece A is moved into the left cooling chamber 621 or the right cooling chamber 623 for intermediate cooling treatment, and then the workpiece A after intermediate cooling treatment is pushed into the rotary hearth secondary heating furnace 7 by the diffusion furnace discharge mechanism for secondary heating treatment, and then the workpiece A after secondary heating treatment is sent into the quenching oil tank 8 for quenching treatment. When the workpiece A is directly pushed into the rotary hearth secondary heating furnace 7 by the diffusion furnace discharge mechanism, the workpiece A is sent into the quenching oil tank 8 for quenching treatment through the rotary hearth secondary heating furnace 7. In order to save space, only the equipment structures with special or particular places in the annular furnace heat treatment production line are described in detail in the subsequent description, and the existing equipment structures are not described again.

[0026] Specifically, in combination with Figure 2 and 3As shown, the double-station intercooler 6 is mainly composed of an intercooler housing 611, an intercooler lining 612, a pair of common passage rails 624, two pairs of intercooler rails 625, two push-pull mechanisms 63, two high-temperature fans 64, two air guide muffs 65, two lift air guide doors 66, two heat exchange mechanisms 67, two protective atmosphere gas supply pipelines (not shown in the figure) and waste gas discharge pipelines (not shown in the figure). The intercooler housing 611 is wrapped outside the intercooler lining 612, the inside of the intercooler lining 612 is sequentially divided into the left cooling chamber 621, the common passage 622 and the right cooling chamber 623 from one side to the other side, the intercooler housing 611 and the intercooler lining 612 combine to form the furnace body structure of the double-station intercooler 6, and two opposite sides thereof are respectively provided with an intercooler inlet and an intercooler outlet which are communicated with the common passage 622. The pair of common passage rails 624 is fixedly laid on the bottom of the common passage 622 in the direction from the intercooler inlet to the intercooler outlet. The two pairs of intercooler rails 625 are fixedly laid on the bottom of the left cooling chamber 621 and the right cooling chamber 623 respectively and are perpendicular to the pair of common passage rails 624. The two push-pull mechanisms 63 are fixedly installed outside the other two opposite side walls which are perpendicular to the side wall provided with the intercooler inlet, and the other two opposite side walls are respectively provided with a head through port (not shown in the figure) corresponding to the position of the push-pull head of the two push-pull mechanisms 63 for the push-pull head to enter and exit. The two high-temperature fans 64 are respectively installed on the top of the left cooling chamber 621 and the right cooling chamber 623. The two air guide muffs 65 are respectively covered on the intercooler rails 625 of the left cooling chamber 621 and the right cooling chamber 623 and are communicated with the high-temperature fans 64. The side of each of the two air guide muffs 65 facing the common passage 622 is provided with an inlet and an outlet, and the two lift air guide doors 66 are respectively arranged at the inlet and the outlet of the two air guide muffs 65. The two heat exchange mechanisms 67 are respectively arranged on the two sides of the air guide muffs 65 in the left cooling chamber 621 and the right cooling chamber 623. The two protective atmosphere gas supply pipelines are respectively arranged outside the top of the left cooling chamber 621 and the right cooling chamber 623 and are communicated with the inside of the left cooling chamber 621 and the right cooling chamber 623, and the protective atmosphere gas supply pipelines are connected with the protective atmosphere main pipeline (not shown in the figure) of the annular furnace heat treatment production line. The waste gas discharge pipeline is arranged outside the top of the common passage near the intercooler inlet and is communicated with the inside of the common passage. The push-pull head of the push-pull mechanism 63 pulls the workpiece A placed on the common passage rail 624 into the left cooling chamber 621 or the right cooling chamber 623 to perform intercooling treatment on the workpiece A, and then pushes the workpiece A back to the common passage rail 624 through the push-pull head to complete the intercooling treatment of the workpiece A. The push-pull mechanism 63 can perform push or pull operation on the tray, which is basically similar to the chain guide pusher device structure, and the difference lies in the structure of the push-pull head, which is combined Figure 4a and 4bTwo kinds of push-pull material head structures commonly used in the current workpiece heat treatment equipment are shown, wherein Figure 4a The push-pull material head 631 structure for the push-pull operation of the bottom of the tray B is shown, and Figure 4b The push-pull material head 631 structure for the push-pull operation of the rim of the tray B is shown. Since the push-pull mechanism 63 is prior art, it will not be described again.

[0027] Further, the heat exchange mechanism 67 is mainly composed of two groups of heat exchange coils (not marked in the figure), two groups of heat exchange fins (not marked in the figure), and a heat exchange medium driving device (not marked in the figure). The two groups of heat exchange coils are fixedly arranged between the two side walls of the middle chamber furnace lining 612 and the space on both sides of the air guide muffle 65, and the medium inflow end and the medium outflow end of the heat exchange coil are both penetrated through the top of the double-station middle chamber 6. The two groups of heat exchange fins are respectively arranged on the two groups of heat exchange coils, and the heat exchange medium driving device is arranged outside the double-station middle chamber 6. When the heat exchange medium is external air, the heat exchange medium driving device is an air extractor, and the medium outflow end is connected with the suction end of the air extractor, and the medium inflow end is communicated with the external environment. When the heat exchange medium is cooling oil, the heat exchange medium driving device is composed of an oil supplement tank (not shown) and a circulating oil pump (not shown) connected with each other. The medium inflow end is connected with the pump outlet of the circulating oil pump, and the medium outflow end is connected with the oil supplement tank.

[0028] In the specific embodiment of the utility model, the rotary hearth type secondary heating furnace 7 is mainly composed of a secondary heating furnace shell 711, a secondary heating furnace lining 712, a circular rotary hearth 72, a plurality of material disc supports 73, a rotary hearth driving device (not shown in the figure), a plurality of radiation heating pipes 74, a plurality of high-temperature fans 75, a protective atmosphere gas supply pipeline (not shown in the figure), a waste gas discharge pipeline (not shown in the figure), an observation window 76 and a manhole 77. The secondary heating furnace shell 711 is wrapped outside the secondary heating furnace lining 712 to combine to form the furnace body structure of the rotary hearth type secondary heating furnace 7, and the inside of the secondary heating furnace lining 712 forms a circular furnace cavity. Two opposite sides of the furnace body structure of the rotary hearth type secondary heating furnace 7 are respectively provided with a secondary heating feeding port and a secondary heating discharging port which are communicated with the circular furnace cavity. The circular rotary hearth 72 is arranged at the bottom of the circular furnace cavity, and the plurality of material disc supports 73 are arranged on the upper side of the circular rotary hearth 72 in a spaced and uniform manner. The rotary hearth driving device is arranged below the circular rotary hearth 72 and is drivingly connected with the circular rotary hearth 72 to drive the circular rotary hearth 72 to rotate in the circumferential direction. The plurality of radiation heating pipes 74 are uniformly arranged in the circular furnace cavity. The plurality of high-temperature fans 75 are uniformly arranged at the upper part of the circular furnace cavity. The protective atmosphere gas supply pipeline is arranged outside the top of the circular furnace cavity and is communicated with the inside of the circular furnace cavity, and the protective atmosphere gas supply pipeline is connected with the protective atmosphere main pipeline of the annular furnace heat treatment production line. The waste gas discharge pipeline is arranged outside the top of the circular furnace cavity near the secondary heating feeding port and is communicated with the inside of the circular furnace cavity. The observation window 76 and the manhole 77 are arranged on the furnace body structure of the rotary hearth type secondary heating furnace 7 and are communicated with the inside of the circular furnace cavity.

[0029] In combination Figure 5 As shown in the specific embodiment of the utility model, the heating furnace 3 is composed of a bottom feeding section 31 and a sealed heating section 32, the setting height of the discharging port of the pre-oxidation furnace 2 is lower than that of the bottom feeding section 31, the bottom of the bottom feeding section 31 is provided with a bottom feeding port 311 and is surrounded by a fire screen (not shown in the figure), and the lifting feeding mechanism 33 is arranged below the bottom feeding port 311 and is aligned with the discharging port of the pre-oxidation furnace 2. The workpiece after pre-oxidation treatment is moved into the lifting feeding mechanism 33 through the discharging port of the pre-oxidation furnace 2, then the workpiece is moved into the bottom feeding section 31 through the bottom feeding port 311 by the lifting feeding mechanism 33, and then the workpiece is moved into the sealed heating section 32 for heating treatment. The bottom feeding structure of the heating furnace 3 and the setting of the fire screen can effectively prevent the external air from entering during the feeding stage, thereby eliminating the occurrence of safety risks such as deflagration and explosion.

[0030] In the specific embodiment of the utility model, the feeding port and the discharging port of the pre-oxidation furnace 2 are both equipped with lifting furnace doors 13, and the bottom charging section 31 and the sealing heating section 32, the discharging port and the heating feeding port of the heating furnace 3, the in-out feeding port and the carburizing feeding port, the diffusion discharging port and the inlet of the intercooler, the outlet of the intercooler and the secondary heating feeding port, and the secondary heating discharging port and the feeding port of the quenching oil tank 8 are all equipped with sealing lifting furnace doors 14, so as to ensure the heating and heat preservation operation of the pre-oxidation furnace 2, and ensure the process safety operation of the heating furnace 3, the push disc diffusion furnace 4, the annular carburizing furnace 5, the double-station intercooler 6 and the rotary hearth secondary heating furnace 7 in the protective atmosphere environment.

[0031] In the specific embodiment of the utility model, the end of the feeding table 1 opposite to the feeding port of the pre-oxidation furnace 2, the outer side of the furnace wall of the pre-oxidation furnace 2 opposite to the discharging port thereof, the outer side of the furnace wall of the bottom charging section 31 opposite to the sealing heating section 32, and the outer side of the furnace wall of the feeding end of the push disc diffusion furnace 4 are all equipped with guide rod pushing device 15 composed of a pressure-driven cylinder body and a push rod, the discharging device equipped on the outer side of the furnace wall of the heating furnace 3 opposite to the discharging port thereof and the diffusion furnace discharging mechanism are both guide chain pushing device 16 composed of a coiled chain track, a chain, a push head, a driving motor and a sprocket, and the inner ring side furnace wall of the annular carburizing furnace 5 opposite to the in-out feeding port thereof and the outer side of the quenching oil tank 8 opposite to the feeding port thereof are both equipped with workpiece supporting device 17. Figure 6As shown, the workpiece supporting device 17 is mainly composed of a supporting mechanism housing 171, a pushing driving motor 173, a screw rod 174, a fork seat 175, a fork 176, a plurality of supporting links 177, a lifting driving motor 178 and an eccentric cam 179, wherein the supporting mechanism housing 171 is a sealed housing and has an open port 172 at one end for being arranged outside the ring side furnace wall of the ring carburizing furnace or outside the quenching oil tank, the pushing driving motor 173 is fixedly installed outside the supporting mechanism housing 171 away from the open port 172, and the output end of the pushing driving motor 173 is drivingly connected with one end of the screw rod 174 fixed in the supporting mechanism housing 171 through a speed reducer, the fork seat 175 has screw holes and is screwed on the screw rod 174 through the screw holes to be arranged on the screw rod 174, and the two sides of the fork seat 175 are embedded in the slides on the two sides of the supporting mechanism housing 171, the fork 176 is above the fork seat 175 and is pivotally connected with the fork 176 and the fork seat 175 through the two ends of the plurality of supporting links 177 to movably connect the fork 176 with the fork seat 175, the lifting driving motor 178 is arranged on the supporting mechanism housing 171 and its output end is drivingly connected with the eccentric cam 179 arranged inside the supporting mechanism housing 171 through a chain, and the fork 176 is placed on the cam portion of the eccentric cam 179, the screw rod 174 is driven to rotate by the pushing driving motor 173 and the eccentric cam 179 is driven to rotate by the lifting driving motor 178 to push or withdraw and lift or lower the fork 176.

[0032] In the specific embodiment of the utility model, combined with Figure 7 As shown, the quenching oil tank 8 has a sealed front chamber 81, a discharging chamber 82, a quenching oil pool 83 and a workpiece quenching moving mechanism 84, the sealed front chamber 81 is provided with an inlet on one side, and the workpiece supporting device 17 is arranged on the outside of the other side, the discharging chamber 82 is provided with a discharging port on one side, the sealed front chamber 81 and the discharging chamber 82 are arranged side by side above the quenching oil pool 83 and the lower parts of the sealed front chamber 81 and the discharging chamber 82 are communicated with the quenching oil pool 83, the quenching oil pool 83 contains quenching oil, the sealed front chamber 81 is sealed and isolated from the discharging chamber 82 by the quenching oil in the quenching oil pool 83, and the workpiece quenching moving mechanism 84 is arranged in the sealed front chamber 81, the discharging chamber 82 and the quenching oil pool 83 to move the workpiece and perform quenching operation.

[0033] In the specific embodiment of the utility model, the cleaning machine 9 can be sequentially arranged and composed of an alkali water soaking position, a clean water spraying position and a drying position, so that the workpiece after quenching treatment can be thoroughly cleaned.

[0034] In addition, as another specific embodiment of the utility model, the annular furnace heat treatment production line can further comprise a tempering furnace 11 and an air cooling table 12, which are sequentially connected between the cleaning machine 9 and the discharging table 10, so that the annular furnace heat treatment production line is provided with tempering and air cooling process links.

[0035] In addition, in the above two specific embodiments of the utility model, the annular furnace heat treatment production line can further comprise a central control unit (not shown in the figure), which is electrically connected with the driving control units of the lifting furnace door, the sealing lifting furnace door, the guide rod pushing device, the guide chain pushing device, the workpiece supporting device, the heat exchange mechanism, the rotary bottom driving device, the radiant heating pipe, the high-temperature fan, the protective atmosphere gas supply pipeline, the waste gas discharge pipeline and other components in the above-mentioned device, as well as the sensor components such as thermocouples, atmosphere sensors, temperature sensors and pressure sensors, so as to control the automatic operation of the annular furnace heat treatment production line through the set instructions. The central control unit can be composed of a programmable logic control circuit (PLC), a centralized control circuit, a central control host computer or a server, and in view of the current application of the programmable logic control circuit, the centralized control circuit, the central control host computer or the server, the operation state of each component is controlled according to the relevant instructions and sensor detection data, which is a very common control mode in the field of automatic control, that is, the existing control technology, so the application of the central control unit to control the operation process of the above-mentioned components in the utility model will not be described in detail. Through the centralized control of the central control unit, the full-automatic operation of the annular furnace heat treatment production line can be realized, thereby saving the labor cost.

[0036] In summary, the utility model sequentially adds a double-station intermediate cooling chamber and a rotary bottom type secondary heating furnace between the push disc diffusion furnace and the quenching oil tank of the annular furnace heat treatment production line, and enables the diffusion furnace discharging mechanism of the push disc diffusion furnace to selectively push the workpiece onto the public channel or directly into the rotary bottom type secondary heating furnace according to the heat treatment requirements of different types of workpieces, so as to selectively implement intermediate cooling, secondary heating and quenching treatment or directly implement quenching treatment on the diffusion treated workpiece. In addition, since the double-station intermediate cooling chamber has left and right cooling chambers and can simultaneously perform intermediate cooling operation on two workpieces, and the rotary bottom type secondary heating furnace can also simultaneously perform secondary heating operation on multiple workpieces, the annular furnace heat treatment production line has the continuous heat treatment capacity and large-scale workpiece processing capacity like an assembly line, thereby having high heat treatment efficiency.

[0037] The above is only a preferred embodiment of the utility model, and is not used to limit the patent range of the utility model, and equivalent changes made by applying the patent concept of the utility model should belong to the patent protection range of the utility model.

Claims

1. A production line of a ring furnace heat treatment for selectively performing carburizing, subcooling, reheating and quenching operations or performing carburizing and quenching operations on workpieces contained in trays, the production line of the ring furnace heat treatment comprising: The application discloses a heat treatment production line of a ring furnace, which comprises an upper feeding table, a pre-oxidation furnace, a heating furnace, a push-disc diffusion furnace, a ring carburizing furnace, a quenching oil tank, a cleaning machine and a discharging table, wherein the upper feeding table is connected with a feeding port of the pre-oxidation furnace, a discharging port of the pre-oxidation furnace is connected with a bottom feeding section of the heating furnace through a lifting feeding mechanism, two opposite side walls of a feeding end of the push-disc diffusion furnace are respectively provided with a heating feeding port and a carburizing feeding port which are in alignment with each other, a discharging port of the heating furnace is sealingly connected with the heating feeding port, and a feeding and discharging port of the ring carburizing furnace is sealingly connected with the carburizing feeding port. The application further discloses a heat treatment production line of a ring furnace, which comprises a double-station intermediate cooling chamber and a rotary hearth secondary heating furnace, wherein the inside of the double-station intermediate cooling chamber is sequentially divided into a left cooling chamber, a common passage and a right cooling chamber from one side to the other side, two opposite side walls of the double-station intermediate cooling chamber adjacent to both ends of the common passage are respectively provided with an intermediate cooling chamber inlet and an intermediate cooling chamber outlet which are in communication with the common passage, one side wall of a discharging end of the push-disc diffusion furnace is provided with a diffusion discharging port, the intermediate cooling chamber inlet is sealingly connected with the diffusion discharging port, a secondary heating feeding port of the rotary hearth secondary heating furnace is sealingly connected with the intermediate cooling chamber outlet, a secondary heating discharging port of the rotary hearth secondary heating furnace is sealingly connected with a feeding port of the quenching oil tank, a discharging port of the quenching oil tank is connected with a feeding port of the cleaning machine, a discharging port of the cleaning machine is connected with the discharging table, and a diffusion furnace discharging mechanism of the push-disc diffusion furnace can selectively push the workpiece after carburizing diffusion treatment to the common passage or directly push the workpiece to the rotary hearth secondary heating furnace. When the workpiece is pushed to the common passage by the diffusion furnace discharging mechanism, the workpiece is moved to the left cooling chamber or the right cooling chamber for intermediate cooling treatment, then the workpiece after the intermediate cooling treatment is pushed to the rotary hearth secondary heating furnace by the diffusion furnace discharging mechanism for secondary heating treatment, and then the workpiece after the secondary heating treatment is sent to the quenching oil tank for quenching treatment. When the workpiece is directly pushed to the rotary hearth secondary heating furnace by the diffusion furnace discharging mechanism, the workpiece is sent to the quenching oil tank for quenching treatment through the rotary hearth secondary heating furnace.

2. The ring furnace heat treatment line according to claim 1, characterized in that, The double-position intermediate cooling chamber is mainly composed of an intermediate cooling chamber shell, an intermediate cooling chamber lining, a pair of common passage guide rails, two pairs of intermediate cooling chamber guide rails, two push-pull material mechanisms, two high-temperature fans, two air guide muffs, two lifting air guide doors, two heat exchange mechanisms, two protective atmosphere gas supply pipelines and a waste gas discharge pipeline. The intermediate cooling chamber shell is wrapped outside the intermediate cooling chamber lining. The interior of the intermediate cooling chamber lining is sequentially divided into the left cooling chamber, the common passage and the right cooling chamber from one side to the other. The intermediate cooling chamber shell and the intermediate cooling chamber lining are respectively provided with the intermediate cooling chamber inlet and the intermediate cooling chamber outlet which are communicated with the common passage. The pair of common passage guide rails are fixedly laid on the bottom of the common passage in the direction from the intermediate cooling chamber inlet to the intermediate cooling chamber outlet. The two pairs of intermediate cooling chamber guide rails are fixedly laid on the bottom of the left cooling chamber and the right cooling chamber respectively and are perpendicular to the pair of common passage guide rails. The two push-pull material mechanisms are fixedly installed on the outside of the other two opposite side walls which are perpendicular to the side wall provided with the intermediate cooling chamber inlet. The other two opposite side walls are respectively provided with material head through holes corresponding to the positions of the push-pull material heads of the two push-pull material mechanisms. The two high-temperature fans are installed on the top of the left cooling chamber and the right cooling chamber respectively. The two air guide muffs are respectively covered on the intermediate cooling chamber guide rails of the left cooling chamber and the right cooling chamber and are communicated with the high-temperature fans. The two air guide muffs are respectively provided with inlets and outlets on the side facing the common passage. The two lifting air guide doors are respectively arranged at the inlets and outlets of the two air guide muffs. The two heat exchange mechanisms are respectively arranged on the two sides of the air guide muffs in the left cooling chamber and the right cooling chamber. The two protective atmosphere gas supply pipelines are respectively arranged on the outside of the top of the left cooling chamber and the right cooling chamber and are communicated with the left cooling chamber and the right cooling chamber. The waste gas discharge pipeline is arranged on the outside of the top of the common passage near the intermediate cooling chamber inlet and is communicated with the common passage. The push-pull material heads of the push-pull material mechanisms pull the workpieces placed on the common passage guide rails into the left cooling chamber or the right cooling chamber to perform intermediate cooling treatment on the workpieces. Then the push-pull material heads push the workpieces back to the common passage guide rails to complete the intermediate cooling treatment of the workpieces.

3. The ring furnace heat treatment line according to claim 2, characterized in that, The heat exchange mechanism is mainly composed of two groups of heat exchange coils, two groups of heat exchange fins and a heat exchange medium driving device. The two groups of heat exchange coils are fixedly arranged in the space between the two sides of the air guide muffle and the two side walls of the middle chamber lining, and the medium inflow end and the medium outflow end of the heat exchange coil are both penetrated through the top of the double-station middle chamber. The two groups of heat exchange fins are respectively arranged on the two groups of heat exchange coils. The heat exchange medium driving device is arranged outside the double-station middle chamber. When the heat exchange medium is external air, the heat exchange medium driving device is an air extractor, and the medium outflow end is connected with the suction end of the air extractor, and the medium inflow end is communicated with the external environment. When the heat exchange medium is cooling oil, the heat exchange medium driving device is composed of an oil supplement tank and a circulating oil pump connected with each other. The medium inflow end is connected with the pump outlet of the circulating oil pump, and the medium outflow end is connected with the oil supplement tank.

4. The ring furnace heat treatment line according to claim 1, characterized in that, The rotary hearth secondary heating furnace is mainly composed of a secondary heating furnace shell, a secondary heating furnace lining, a circular rotary hearth, a plurality of material disc supports, a rotary hearth driving device, a plurality of radiant heating pipes, a plurality of high-temperature fans, a protective atmosphere gas supply pipeline, a waste gas discharge pipeline, an observation window and a maintenance door. The secondary heating furnace shell covers the outside of the secondary heating furnace lining. The inside of the secondary heating furnace lining forms a circular furnace cavity. Two opposite sides of the secondary heating furnace shell and the secondary heating furnace lining are respectively provided with the secondary heating inlet and the secondary heating outlet which are communicated with the circular furnace cavity. The circular furnace cavity is provided with the circular rotary hearth at the bottom. The upper side of the circular rotary hearth is provided with the plurality of material disc supports which are arranged at intervals and uniformly. The rotary hearth driving device is arranged below the circular rotary hearth and is drivingly connected with the circular rotary hearth to drive the circular rotary hearth to rotate circumferentially. The plurality of radiant heating pipes are uniformly arranged in the circular furnace cavity. The plurality of high-temperature fans are uniformly arranged at the upper part of the circular furnace cavity. The protective atmosphere gas supply pipeline is arranged outside the top of the circular furnace cavity and is communicated with the circular furnace cavity. The waste gas discharge pipeline is arranged outside the top of the circular furnace cavity near the secondary heating inlet and is communicated with the circular furnace cavity. The observation window and the maintenance door are arranged on the secondary heating furnace shell and the secondary heating furnace lining and are communicated with the circular furnace cavity.

5. The ring furnace heat treatment line according to claim 1, characterized in that, The heating furnace is composed of a bottom charging section and a sealed heating section which are sealingly connected. The setting height of the discharge outlet of the pre-oxidation furnace is lower than that of the bottom charging section. The bottom of the bottom charging section is provided with a bottom charging port and is surrounded by a fire curtain. The lifting charging mechanism is arranged below the bottom charging port and is positioned with the discharge outlet of the pre-oxidation furnace. The workpiece after pre-oxidation treatment is moved into the lifting charging mechanism through the discharge outlet of the pre-oxidation furnace, is lifted by the lifting charging mechanism, is moved into the bottom charging section through the bottom charging port, and then is moved into the sealed heating section for heating treatment.

6. The ring furnace heat treatment line according to claim 5, characterized in that, The feeding port and discharging port of the pre-oxidation furnace are equipped with lifting furnace doors, and sealing lifting furnace doors are arranged between the bottom charging section and the sealing heating section, between the discharging port and the feeding port of the heating furnace, between the feeding and discharging ports and the carburizing feeding port, between the diffusion discharging port and the inlet of the intercooler, between the outlet of the intercooler and the secondary heating feeding port, and between the secondary heating discharging port and the feeding port of the quenching oil tank.

7. The ring furnace heat treatment line according to claim 6, characterized in that, A guide rod pushing device composed of a pressure driving cylinder and a pushing rod is arranged on the feeding end of the push disc diffusion furnace, and the outer side of the furnace wall of the heating furnace opposite to the discharging port, the outer side of the furnace wall of the bottom charging section opposite to the sealing heating section, and the outer side of the furnace wall of the push disc diffusion furnace opposite to the feeding end are all equipped with the guide rod pushing device.

8. The ring furnace heat treatment line according to claim 1, characterized in that, Further comprising: A tempering furnace and an air cooling table are sequentially connected between the cleaning machine and the discharging table.

9. The ring furnace heat treatment line according to claim 1, characterized in that, The cleaning machine is composed of an alkali water soaking section, a water spraying section and a drying section arranged in sequence.

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