A continuous annealing furnace

Abstract

The utility model provides a continuous annealing furnace, include: muffle furnace, the utility model provides a continuous annealeing furnace, through the reasonable intercalation of baking furnace and purging process, operation saves time, significantly improves equipment utilization, adapts the efficient scheduling demand of centralized production, strictly controls the oxygen content of entrance area, dew point and supercooling section detection data, combines " oxygen content is accurate to start heating when <=7000ppm " logic, ensures that muffle furnace, cooling section etc. Core area is always in argon protection atmosphere, effectively avoids material oxidation, improves the surface quality stability of titanium roll etc. Precise material, through the speed of cooling fan, furnace pressure regulating valve opening and argon flow of grading regulation, reduces argon waste while guaranteeing purging effect, matches heating rate segmented control, avoids the thermal stress of furnace body because of temperature abrupt change, prolongs the service life of equipment, process step is clear, and key parameter quantization is controllable, reduces the dependence on the experience of operating personnel.

Description

Technical Field

[0001] This utility model relates to the field of vertical annealing furnace technology, and more particularly to a continuous annealing furnace. Background Technology

[0002] In a vertical continuous annealing furnace, the strip material is prone to react with oxygen in the air under high temperature, resulting in surface oxidation. This oxidation not only affects the appearance quality of the product, but also reduces the mechanical properties and service life of the product. Therefore, in order to avoid surface oxidation of the strip material, the furnace must be purged with protective gas before the heat treatment process to create an oxygen-free or low-oxygen heat treatment environment.

[0003] The vertical continuous annealing furnace uses argon as a protective gas and has a production capacity of 20,000 tons / year. The existing furnace purging process is extremely complex, with each purging taking a long time and consuming a lot of energy. Due to intense market competition, enterprises are accelerating their production pace and facing greater pressure to reduce costs and increase efficiency. This time-consuming and energy-intensive purging method can no longer meet the needs of enterprise development.

[0004] The existing furnace purging process has the following problems: On-site production is centralized, requiring furnace shutdowns and restarts, resulting in a complex and inconvenient process; purging is time-consuming, significantly reducing production efficiency; the average argon flow rate during purging is only 150 m³ / h. 3 The purging time is relatively long, and the argon consumption after purging is approximately 10800 m³ / h. 3 It consumes a lot of energy, which increases production costs. Because argon is dense, it will sink in the air. At the same time, due to the unique structural characteristics of the vertical continuous annealing furnace, the argon in the furnace is concentrated at the lower inlet of the furnace during the purging process, which greatly increases the leakage rate of argon.

[0005] Therefore, it is necessary to provide a continuous annealing furnace to solve the above-mentioned technical problems. Utility Model Content

[0006] This utility model provides a continuous annealing furnace, which solves the problems of centralized production, which involves furnace shutdowns and restarts, resulting in complex processes that are inconvenient to operate; lengthy purging times that severely reduce production efficiency; and an average argon flow rate of 150 m³ / h during purging. 3 The purging time is relatively long, and the argon consumption after purging is approximately 10800 m³ / h. 3 The energy consumption is relatively large, which increases production costs. Due to the high density of argon, it will sink in the air. At the same time, due to the unique structural characteristics of the vertical continuous annealing furnace, the argon in the furnace is concentrated at the lower inlet of the furnace during the purging process, which greatly increases the problem of argon leakage.

[0007] To solve the above-mentioned technical problems, this utility model provides a continuous annealing furnace, including: a muffle furnace;

[0008] The subcooling section is located at the top of the inside of the muffle furnace. The top of the muffle furnace is equipped with a cooling section. A top chamber is fixedly installed on the top of the cooling section. A downward channel is fixedly installed at the bottom of one side of the top chamber. The bottom of the muffle furnace is the inlet and needs to be sealed. The bottom of the downward channel is the outlet and needs to be sealed.

[0009] An argon gas station is located at the bottom of one side of the muffle furnace. The inlet at the bottom of the muffle furnace is connected to the exhaust pipe of an exhaust fan. A purification system is located on the other side of the muffle furnace.

[0010] Preferably, the muffle furnace, the cooling section, the top chamber, and the downward passage are interconnected.

[0011] Preferably, an oxygen content analyzer and a dew point analyzer are installed at the inlet of the muffle furnace.

[0012] Preferably, multiple sets of cooling water pipes are installed at equal intervals from top to bottom on the outer surface of the cooling section, and multiple flow guiding devices are installed at equal intervals from top to bottom inside the cooling section and the downward channel. Oxygen content sensors and dew point sensors are installed on both sides of the outer surface of the top chamber and the downward channel. Flow guiding plates are fixedly installed on both sides of the top of the top chamber. Gas inlet pipes are provided on both sides of the outer surface of the top chamber. An argon gas main pipeline pressure sensor is fixedly installed on one side of the outer surface of the muffle furnace.

[0013] Preferably, the flow guiding device includes a guide block, a guide groove, and extension plates. The guide block is fixedly installed inside the cooling section, the guide groove is opened in the middle of one side of the guide block, and multiple extension plates are equidistantly and fixedly installed around the inside of the guide groove.

[0014] Preferably, a heat-conducting device is fixedly installed around the outer surface of the flow guiding device. The heat-conducting device includes heat dissipation columns and heat dissipation protrusions. The heat dissipation columns are fixedly installed on the outer surface of the guide block, and a plurality of heat dissipation protrusions are respectively fixedly installed on the outer surface of the heat dissipation columns.

[0015] Compared with related technologies, the continuous annealing furnace provided by this utility model has the following beneficial effects:

[0016] This invention provides a continuous annealing furnace. By rationally interleaving the furnace drying and purging processes, the entire process of restarting the furnace after a shutdown is controlled within 30 hours. Compared with traditional step-by-step operations, this saves time, significantly improves equipment utilization, and adapts to the efficient scheduling requirements of centralized production. It strictly controls the oxygen content, dew point, and supercooled section detection data in the inlet area. Combined with the logic of "precisely starting heating when oxygen content ≤ 7000ppm," it ensures that core areas such as the muffle furnace and cooling section are always in an argon protective atmosphere, effectively preventing material oxidation and improving the surface quality stability of precision materials such as titanium coils. Through graded adjustment of cooling fan speed, furnace pressure regulating valve opening, and argon flow, it reduces argon waste while ensuring purging effectiveness. Combined with segmented heating rate control, it avoids thermal stress caused by sudden temperature changes in the furnace body, extending equipment lifespan. The process steps are clearly defined, and key parameters are quantifiable and controllable, reducing reliance on operator experience. The design further reduces errors caused by human intervention through continuous air intake by exhaust fans and water-cooled pipelines to ensure cooling effect, providing a reliable start-up solution for centralized production of vertical annealing furnaces. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a first embodiment of a continuous annealing furnace provided by this utility model;

[0018] Figure 2 A flow diagram of a continuous annealing furnace provided by this utility model;

[0019] Figure 3 This is a schematic diagram of the structure of a second embodiment of a continuous annealing furnace provided by this utility model;

[0020] Figure 4 for Figure 3 The diagram shows the structure of the flow guiding device.

[0021] Figure 5 for Figure 3 The diagram shows the internal structure of the flow guiding device.

[0022] The diagram is labeled as follows: 1. Muffle furnace, 2. Subcooling section, 3. Cooling section, 4. Top chamber, 5. Downward passage, 6. Exhaust fan, 7. Oxygen content analyzer, 8. Purification system, 9. Argon station, 10. Cooling water pipe, 11. Flow guiding device, 111. Guide block, 112. Guide groove, 113. Extension plate, 12. Argon main pipeline pressure sensor, 13. Oxygen content sensor, 14. Dew point sensor, 15. Flow guiding plate, 16. Inlet pipe, 17. Heat dissipation column, 18. Heat dissipation protrusion. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] First Embodiment

[0025] Please refer to the following: Figure 1 and Figure 2 ,in, Figure 1 This is a schematic diagram of the structure of a first embodiment of a continuous annealing furnace provided by this utility model; Figure 2 A schematic diagram of a continuous annealing furnace provided by this utility model.

[0026] A continuous annealing furnace includes: a muffle furnace 1;

[0027] Subcooling section 2 is located at the top inside the muffle furnace 1. A cooling section 3 is located at the top of the muffle furnace 1. A top chamber 4 is fixedly installed at the top of the cooling section 3. A downward channel 5 is fixedly installed at the bottom of one side of the top chamber 4. The bottom of the muffle furnace 1 is the inlet and needs to be sealed. The bottom of the downward channel 5 is the outlet and needs to be sealed.

[0028] Argon station 9 is located at the bottom of one side of muffle furnace 1. The inlet of the bottom of muffle furnace 1 is connected to the exhaust pipe of exhaust fan 6. A purification system 8 is located on the other side of muffle furnace 1.

[0029] The muffle furnace 1, the cooling section 3, the top chamber 4, and the downward channel 5 are interconnected.

[0030] An oxygen content analyzer 7 and a dew point analyzer are installed at the inlet of the muffle furnace 1.

[0031] The working principle of the continuous annealing furnace provided by this utility model is as follows:

[0032] During operation, the preparation work before furnace purging begins first. The furnace gas exhaust fan 6 is started and the speed is adjusted to 50%. All cooling fans are started and the speed is adjusted to 10%. The pressure of the argon station 9 tank is adjusted to 0.45~0.6MPa. The heating element is started and the furnace temperature is heated to 100℃.

[0033] Argon station 9 supplies argon gas into the furnace. Open the furnace argon direct supply shut-off valve SOV-12R03; open the argon flow regulating valve PCV-12R03 to 80%~100%; adjust the argon pressure regulating valve PCV-12R01 to automatic mode and set the control pressure to 10 kPa (8~12 kPa); open the argon main pipeline shut-off valve SOV-12R00; open the argon main pipeline manual valve (argon station); adjust the opening of the argon flow regulating valve PCV-12R03 to ensure the total argon flow rate is between 90~200 Nm³. 3 Between / h.

[0034] Furnace purging; cooling fan speed adjusted to 15%~50%; furnace pressure regulating valve PCV-12R02 opening adjusted to 15%~45%; furnace gas exhaust fan 6 speed adjusted to keep furnace pressure PE-10F03 in the transition cooling section between +50~+200Pa; four hours later, start the two oxygen content analyzers 7 at the transition cooling section and inlet seal; when the oxygen content in the transition cooling section is ≤7000ppm, muffle furnace 1 is heated to 800℃, and zone 1 is heated to 700℃. 80℃, Zone 2 temperature rises to 680℃; heating rate is 50℃ / h for temperatures below 300℃, and 100℃ / h for temperatures above 300℃; adjust furnace pressure so that the inlet furnace pressure value PE-10F01 is between +80~+300Pa; after holding at 900℃ for 3 hours, during the process the inlet dew point first drops and then rises back to about -30, adjust the temperature to the production temperature, replace the titanium coil, adjust the furnace pressure regulating valve PCV-12R02 opening to 5%~15%, stabilize the furnace pressure, and production can begin once the test piece enters the furnace without oxidation.

[0035] Compared with related technologies, the continuous annealing furnace provided by this utility model has the following beneficial effects:

[0036] This utility model provides a continuous annealing furnace. By rationally interleaving the furnace drying and purging processes, the entire process of restarting the furnace after a shutdown is controlled within 30 hours. Compared with traditional step-by-step operations, this saves time, significantly improves equipment utilization, and is suitable for the efficient scheduling requirements of centralized production. It strictly controls the oxygen content, dew point, and subcooling section detection data in the inlet area, combined with the requirement of "oxygen content ≤ 7000ppm". The system employs a precise start-up and heating logic to ensure that core areas such as the muffle furnace 1 and cooling section 3 are always under an argon protective atmosphere, effectively preventing material oxidation and improving the surface quality stability of precision materials such as titanium coils. By adjusting the cooling fan speed, furnace pressure regulating valve opening, and argon flow rate in stages, the system ensures purging effectiveness while reducing argon waste. Combined with segmented heating rate control, the system avoids thermal stress caused by sudden temperature changes in the furnace body, extending equipment lifespan. The process steps are clearly defined, and key parameters are quantifiable and controllable, reducing reliance on operator experience. The design further reduces errors caused by human intervention through features such as continuously reducing the amount of air brought in by the material using exhaust fan 6 and ensuring cooling effect through water-cooled pipelines. This provides a reliable start-up solution for centralized production of vertical annealing furnaces.

[0037] Second Embodiment

[0038] Please refer to the following: Figure 3 , Figure 4 and Figure 5 Based on the continuous annealing furnace provided in the first embodiment of this application, the second embodiment of this application proposes another continuous annealing furnace. The second embodiment is merely a preferred embodiment of the first embodiment, and the implementation of the second embodiment will not affect the separate implementation of the first embodiment.

[0039] Specifically, the second embodiment of this application provides a continuous annealing furnace in that multiple sets of cooling water pipes 10 are installed at equal intervals from top to bottom on the outer surface of the cooling section 3; multiple flow guiding devices 11 are installed at equal intervals from top to bottom inside the cooling section 3 and the downward channel 5; oxygen content sensors 13 and dew point sensors 14 are installed on both sides of the outer surface of the top chamber 4 and the downward channel 5; flow guiding plates 15 are fixedly installed on both sides of the top inside the top of the top chamber 4; air inlet pipes 16 are provided on both sides of the outer surface of the top chamber 4; and an argon gas main pipeline pressure sensor 12 is fixedly installed on one side of the outer surface of the muffle furnace 1.

[0040] The flow guiding device 11 includes a guide block 111, a guide groove 112, and an extension plate 113. The guide block 111 is fixedly installed inside the cooling section 3. The guide groove 112 is opened in the middle of one side of the guide block 111. Multiple extension plates 113 are equidistantly and fixedly installed around the inside of the guide groove 112.

[0041] Heat-conducting devices are fixedly installed around the outer surface of the flow guiding device 11. The heat-conducting devices include heat dissipation pillars 17 and heat dissipation protrusions 18. The heat dissipation pillars 17 are fixedly installed on the outer surface of the guide block 111, and a plurality of heat dissipation protrusions 18 are respectively fixedly installed on the outer surface of the heat dissipation pillars 17.

[0042] Cooling water pipes 10 are installed on the outer surface of cooling section 3. Three layers of fans on the upper and lower surfaces of cooling section 3 can work with cooling water pipes 10 to further cool down the air. Heat dissipation columns 17 and heat dissipation protrusions 18 exchange heat and cold with the hot air inside cooling section 3 to improve the heat dissipation effect. Extension plate 113 is also made of heat dissipation block material and extends into the middle of cooling section 3 to increase the heat dissipation effect of airflow.

[0043] The conical guide groove 112 increases airflow and reduces airflow stagnation.

[0044] The working principle of the continuous annealing furnace provided by this utility model is as follows:

[0045] During operation, a conical airflow guide device 11 is first installed in the cooling section 3 and the downward channel 5. The conical guide groove 112 guides the airflow and increases the airflow fluidity.

[0046] Oxygen content sensor 13 and dew point sensor 14 are added to the top chamber 4 and the down channel 5 to provide real-time feedback on the purging effect of each area: if the oxygen content in the top chamber is >5000ppm, the independent argon branch pipe of the top chamber can be opened to directionally supplement argon through the inlet pipe 16.

[0047] Compared with related technologies, the continuous annealing furnace provided by this utility model has the following beneficial effects:

[0048] This utility model provides a continuous annealing furnace. By setting a flow guiding device 11 in the connection area between the subcooling section and the cooling section, the argon gas is guided to flow towards the exhaust port, avoiding the formation of dead air flow, improving air flow flow, reducing air flow stagnation, and adding a pressure sensor for the main argon gas pipeline. When the pressure drops suddenly (such as due to gas leakage), an audible and visual alarm is immediately triggered and the heating element is automatically shut down to prevent oxygen deficiency in the furnace from causing overheating and damage to the heating element, thereby improving the practicality of the device.

[0049] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A continuous annealing furnace, characterized in that, include: Muffle furnace; The subcooling section is located at the top of the inside of the muffle furnace. The top of the muffle furnace is equipped with a cooling section. A top chamber is fixedly installed on the top of the cooling section. A downward channel is fixedly installed at the bottom of one side of the top chamber. The bottom of the muffle furnace is the inlet and needs to be sealed. The bottom of the downward channel is the outlet and needs to be sealed. An argon gas station is located at the bottom of one side of the muffle furnace. The inlet at the bottom of the muffle furnace is connected to the exhaust pipe of an exhaust fan. A purification system is located on the other side of the muffle furnace.

2. A continuous annealing furnace according to claim 1, characterized in that The muffle furnace, the cooling section, the top chamber, and the downward passage are interconnected.

3. A continuous annealing furnace according to claim 1, characterized in that An oxygen content analyzer and a dew point analyzer are installed at the inlet of the muffle furnace.

4. A continuous annealing furnace according to claim 1, characterized in that Multiple sets of cooling water pipes are installed at equal intervals from top to bottom on the outer surface of the cooling section. Multiple flow guiding devices are installed at equal intervals from top to bottom inside the cooling section and the downward channel. Oxygen content sensors and dew point sensors are installed on both sides of the outer surface of the top chamber and the downward channel. Flow guiding plates are fixedly installed on both sides of the top of the top chamber. Gas inlet pipes are provided on both sides of the outer surface of the top chamber. An argon gas main pipeline pressure sensor is fixedly installed on one side of the outer surface of the muffle furnace.

5. A continuous annealing furnace according to claim 4, characterized in that The flow guiding device includes a guide block, a guide groove, and extension plates. The guide block is fixedly installed inside the cooling section, the guide groove is opened in the middle of one side of the guide block, and multiple extension plates are equidistantly and fixedly installed around the inside of the guide groove.

6. A continuous annealing furnace according to claim 5, characterized in that, A heat-conducting device is fixedly installed around the outer surface of the flow guiding device. The heat-conducting device includes heat dissipation columns and heat dissipation protrusions. The heat dissipation columns are fixedly installed on the outer surface of the guide block, and a plurality of heat dissipation protrusions are respectively fixedly installed on the outer surface of the heat dissipation columns.

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