Atmosphere control device and muffle bright heat treatment furnace having the same

Abstract

The utility model discloses an atmosphere control device and have the atmosphere control device's muffle type bright heat treatment furnace, the atmosphere control device sets up between furnace body and hydrogen main inlet pipeline, include: humidification storage tank, its inside definition humidification chamber and accommodate humidification liquid, the bottom of humidification storage tank is equipped with with humidification chamber intercommunication's air inlet, liquid supplementing mouth and liquid discharge mouth, and its top is equipped with vent and air outlet, multistage pressure reduction control bypass, intercommunication hydrogen main inlet pipeline with the air inlet between humidification storage tank, including pressure reduction pipe and a plurality of pressure reduction valves that are set up on pressure reduction pipe, for hydrogen main inlet pipeline delivery gas carries out multistage pressure reduction to work pressure. The utility model has the beneficial effects that: accurate control atmosphere and humidity atmosphere, avoid producing stick steel scratch phenomenon, reduce product outer surface polishing cost.

Description

Technical Field

[0001] This utility model belongs to the technical field of industrial heat treatment equipment, and relates to an atmosphere control device and a muffle bright heat treatment furnace having the atmosphere control device, especially an atmosphere control device based on multi-stage pressure reduction and dynamic humidity adjustment and a muffle bright heat treatment furnace having the atmosphere control device. Background Technology

[0002] In the field of steel pipe heat treatment, muffle furnaces have become the mainstream equipment for bright annealing processes due to their rapid atmosphere replacement capability, flexible temperature control characteristics, and simplified structure. Bright annealing is an important and crucial step in the production of seamless steel pipes. With the increasing market demands for products in recent years, steel pipe heat treatment has gradually shifted from conventional black annealing to bright annealing. Bright annealing primarily involves removing oxide scale from the steel pipe surface and relieving stress at high temperatures using a strongly reducing protective gas to achieve a bright finish. Compared to black annealing, it allows for direct finishing of the finished product, eliminating the intermediate pickling step and significantly improving environmental protection and energy efficiency. However, for different steel grades requiring different heat treatments, atmosphere control during bright annealing is particularly important. Different steel grades necessitate careful control of the atmosphere during the bright annealing process to achieve the desired process results. However, current muffle furnaces have significant technical defects: 1. Crude gas pressure control: When in use, muffle furnaces are usually directly connected to a high-pressure hydrogen pipeline of 1.0-1.5MPa to form a hydrogen atmosphere inside the furnace. CN 109539772 A discloses an explosion-proof device for a muffle furnace. The muffle furnace in this application has a hydrogen inlet pipe at one end and a hydrogen outlet pipe at the other end. The hydrogen inlet pipe in this application is directly connected to the high-pressure hydrogen pipeline without pressure reduction treatment. Excessive gas pressure can easily lead to fluctuations in gas flow rate, which can easily cause laminar flow turbulence; 2. Inaccurate atmosphere and humidity regulation: The lack of precise atmosphere and humidity control modules results in large dew point temperature deviations, causing phenomena such as steel sticking, scratches, and furnace jamming to occur during the heat treatment of different steel grades; 3. High surface defect rate: Due to the uncontrolled gas dynamic parameters, the incidence of steel sticking and scratch defects is high, requiring subsequent polishing of the product surface, increasing production costs.

[0003] Therefore, there is an urgent need for an atmosphere control device that can precisely regulate the atmosphere and humidity, avoid steel sticking and scratching, and reduce product production costs. Summary of the Invention

[0004] In order to overcome the defects in the prior art, this application proposes an atmosphere control device that can precisely control the atmosphere and humidity, avoid steel sticking and scratching, and reduce the cost of product surface polishing, as well as a muffle bright heat treatment furnace with atmosphere control device.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] The atmosphere control device of this utility model is disposed between the muffle furnace and the main hydrogen inlet pipeline, comprising:

[0007] A humidifying storage tank, which internally defines a humidifying chamber and contains humidifying liquid, has an air inlet, a liquid replenishment inlet, and a liquid drain outlet at its bottom that communicate with the humidifying chamber, and an vent outlet and an air outlet at its top. The air outlet is connected to the circulating air duct of a muffle furnace via an air outlet pipe.

[0008] A multi-stage pressure reduction and control bypass connects the main hydrogen inlet pipeline to the inlet of the humidification storage tank. It includes a pressure reducing pipe and multiple pressure reducing valves connected in series on the pressure reducing pipe, and is used to reduce the pressure of the gas transported by the main hydrogen inlet pipeline to the working pressure in multiple stages.

[0009] As a preferred embodiment of this application, the multi-stage pressure reduction and control bypass adopts a two-stage pressure reduction architecture. One end of the pressure reduction pipe is connected to the main hydrogen inlet pipeline, and the other end is connected to the inlet of the humidification storage tank. The pressure reduction pipe is equipped with a first-stage pressure reducing valve and a second-stage pressure reducing valve in sequence along the gas flow direction, which are used to regulate the gas transported by the main hydrogen inlet pipeline to the working pressure in two stages.

[0010] As a preferred embodiment of this application, the input gas pressure of the main hydrogen inlet pipeline is 1.0-1.5 MPa, and the working pressure after multi-stage pressure reduction and bypass pressure reduction is 100 mbar-400 mbar.

[0011] As a preferred embodiment of this application, the input gas of the main hydrogen inlet pipeline is reduced from 1.0-1.5 MPa to 0.3-0.5 MPa after being reduced by a first-stage pressure reducing valve, and then further reduced to 100 mbar-400 mbar by a second-stage pressure reducing valve.

[0012] As a preferred embodiment of this application, the input gas of the main hydrogen inlet pipeline is reduced from 1.5 MPa to 0.4 MPa after being reduced by a first-stage pressure reducing valve, and then reduced to 100 mbar by a second-stage pressure reducing valve.

[0013] As a preferred embodiment of this application, a flow meter, a pointer valve, and a first solenoid valve are also provided on the pressure reducing pipe downstream of the pressure reducing valve.

[0014] As a preferred embodiment of this application, the atmosphere control device further includes a PLC control system, which is electrically connected to the primary pressure reducing valve, the secondary pressure reducing valve, the flow meter, the first solenoid valve, and the second solenoid valve via a DP bus to form a master-slave industrial control network for dynamically adjusting the gas atmosphere and humidity inside the muffle furnace.

[0015] The PLC control system serves as the DP master station, while the primary pressure reducing valve, secondary pressure reducing valve, flow meter, first solenoid valve, and second solenoid valve serve as DP slave stations.

[0016] The PLC control system is configured as follows:

[0017] Real-time acquisition of operating status data from each DP slave station;

[0018] Based on preset process parameters, the opening degree of the first-stage pressure reducing valve and the second-stage pressure reducing valve, as well as the on / off state of the first solenoid valve and the second solenoid valve, are dynamically adjusted through periodic data exchange.

[0019] The gas atmosphere concentration and humidity parameters inside the muffle furnace 1 are controlled in a closed loop based on the flow signals fed back by the flow meter and humidity sensor.

[0020] As a preferred embodiment of this application, the humidification tank is equipped with a liquid level detector, which is electrically connected to the PLC controller and is used to monitor the liquid level of the humidification liquid in the humidification chamber in real time.

[0021] As a preferred embodiment of this application, the gas outlet is connected to a gas outlet pipe, and the gas outlet is connected to the gas inlet of the muffle furnace through the gas outlet pipe. A second solenoid valve electrically connected to the PLC controller is installed on the gas outlet pipe.

[0022] As a preferred embodiment of this application, the humidification tank is equipped with a level sensor connected to the PLC controller for real-time monitoring of the liquid level of the humidification liquid in the humidification chamber.

[0023] As a preferred embodiment of this application, the side wall of the humidification tank is provided with a transparent observation window for observing the liquid level of the humidification liquid in the humidification chamber.

[0024] As a preferred embodiment of this application, the atmosphere control device further includes a dew point sensor connected to the PLC controller for detecting the gas dew point temperature.

[0025] As a preferred embodiment of this application, the atmosphere control device further includes an automatic liquid replenishment device, the outlet of which is connected to the liquid replenishment pipe of the humidification storage tank, and the control terminal of which is electrically connected to the PLC controller for replenishing liquid into the humidification storage tank.

[0026] As a preferred embodiment of this application, the humidifying liquid is deionized water.

[0027] As a preferred embodiment of this application, the automatic liquid replenishment device includes a liquid replenishment pump, which is connected to the liquid replenishment port of the humidification storage tank via a water replenishment pipe. The water replenishment pipe is equipped with a control valve, which is connected to the PLC controller.

[0028] This application also provides a muffle-type bright heat treatment furnace, including a muffle furnace, a main hydrogen inlet pipeline, and the atmosphere control device disposed between the muffle furnace and the main hydrogen inlet pipeline.

[0029] As a preferred embodiment of this application, the muffle furnace includes a furnace body and a circulating air duct. The circulating air duct has a gas circulation inlet, a gas circulation outlet, and a gas filling port that are interconnected. The gas circulation inlet and the gas circulation outlet are connected to the furnace body, and the gas filling port is connected to the gas outlet of the humidification storage tank through an outlet pipe.

[0030] The beneficial effects of this utility model are:

[0031] 1. This application adopts a two-stage pressure reducing structure (first-stage pressure reducing valve + second-stage pressure reducing valve) to achieve precise pressure regulation from 1.0-1.5MPa to 100-400mbar. Combined with PLC closed-loop control, it reduces pressure fluctuations and significantly improves the stability of hydrogen humidification.

[0032] 2. This application uses dew point detection and automatic liquid replenishment device to ensure process gas humidity control, so as to avoid phenomena such as steel sticking, scratches, and furnace jamming during heat treatment, resulting in bright products, reducing the need for subsequent product surface polishing, and lowering production costs.

[0033] 3. This application uses a humidification storage tank to monitor the deionized water level in real time, and combines this with a solenoid valve to quickly shut off the pressure, effectively preventing the risk of abnormal pressure and dry burning.

[0034] 4. This application has two main functions: automatic output adjustment and manual control. It enables remote monitoring through a PLC controller, meets the needs of industrial integration, and effectively improves equipment automation.

[0035] 5. The two-stage depressurization process of this application can significantly reduce hydrogen consumption, the automatic liquid replenishment device reduces the frequency of manual intervention, and the overall operation and maintenance cost is reduced. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the atmosphere control device of this utility model (solid arrows represent the direction of gas flow, and dashed arrows represent the direction of liquid flow).

[0037] Figure 2 This is a schematic diagram of the structure of the muffle-type bright heat treatment furnace of this utility model (solid arrows represent the direction of gas flow, and dashed arrows represent the direction of liquid flow).

[0038] Figure 3 This is the control diagram of this utility model.

[0039] Figure 4 Dynamic response curve for gas humidification.

[0040] Among them, 1-muffle furnace; 11-circulating air duct; 2-hydrogen main inlet pipeline; 3-humidification storage tank; 31-air inlet; 32-liquid replenishment port; 33-liquid drain port; 34-vent port; 35-air outlet; 36-air outlet pipe; 37-second solenoid valve; 38-transparent observation window; 4-multi-stage pressure reduction and control bypass; 41-pressure reducing pipe; 42-first-stage pressure reducing valve; 43-second-stage pressure reducing valve; 44-flow meter; 45-pointer valve; 46-first solenoid valve. Detailed Implementation

[0041] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application.

[0042] It should be noted that the process equipment or apparatus not specifically mentioned in the following embodiments are all conventional equipment or apparatus in the art.

[0043] Furthermore, it should be understood that the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps, does not preclude the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps, unless otherwise stated. It should also be understood that the combined connection relationship between one or more devices / apparatus mentioned in this application does not preclude the existence of other devices / apparatus before or after the combined devices / apparatus, or the insertion of other devices / apparatus between these explicitly mentioned devices / apparatus, unless otherwise stated. Moreover, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying each method step, and not for limiting the order of the method steps or limiting the scope of implementation of this application. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of implementation of this application.

[0044] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0045] In the description of this application, it should be understood that the terms "upper," "lower," "left," "right," "inner," "outer," "axial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0046] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0047] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0048] The present application will be further described below with reference to specific embodiments, but the scope of protection of the present application is not limited thereto.

[0049] like Figure 1 and Figure 2 As shown, the atmosphere control device of this utility model is disposed between the muffle furnace 1 and the main hydrogen inlet pipeline 2, and includes:

[0050] A humidifying storage tank 3, which internally defines a humidifying chamber and contains humidifying liquid, has an air inlet 31, a liquid replenishment port 32, and a liquid drain port 33 at its bottom, all communicating with the humidifying chamber. Its top has a vent port 34 and an air outlet 35, with the air outlet 35 connected to the circulating air duct 11 of the muffle furnace 1 via an air outlet pipe 36.

[0051] The multi-stage pressure reduction and control bypass 4 is connected between the main hydrogen inlet pipeline 2 and the inlet 31 of the humidification storage tank 3. It includes a pressure reducing pipe 41 and multiple pressure reducing valves connected in series on the pressure reducing pipe 41, and is used to reduce the pressure of the gas transported by the main hydrogen inlet pipeline 2 to the working pressure in multiple stages.

[0052] like Figure 1 As shown, the multi-stage pressure reduction and control bypass 4 adopts a two-stage pressure reduction architecture. One end of the pressure reduction pipe 41 is connected to the main hydrogen inlet pipe 2, and the other end is connected to the inlet 31 of the humidification storage tank 3. The pressure reduction pipe 41 is equipped with a first-stage pressure reducing valve 42 and a second-stage pressure reducing valve 43 along the gas flow direction, which are used to adjust the gas transported by the main hydrogen inlet pipe 2 to the working pressure in two stages.

[0053] like Figure 1 As shown, a flow meter 44, an adjustable pointer valve 45, and a first solenoid valve 46 are also provided on the pressure reducing pipe 41 downstream of the pressure reducing valve.

[0054] In some embodiments of this application, the input gas pressure of the main hydrogen inlet pipeline 2 is 1.0-1.5 MPa, and the working pressure after pressure reduction by the multi-stage pressure reduction and control bypass 4 is 100 mbar-400 mbar.

[0055] like Figure 3 As shown, the atmosphere control device also includes a PLC control system, which is electrically connected to the first-stage pressure reducing valve 42, the second-stage pressure reducing valve 43, the flow meter 44, the first solenoid valve 46, and the second solenoid valve 37 via a DP bus to form a master-slave industrial control network, used to dynamically adjust the gas atmosphere and humidity inside the muffle furnace 1.

[0056] The PLC control system serves as the DP master station, while the first-stage pressure reducing valve 42, the second-stage pressure reducing valve 43, the flow meter 44, the first solenoid valve 46, and the second solenoid valve 37 serve as DP slave stations.

[0057] The PLC control system is configured as follows:

[0058] Real-time acquisition of operating status data from each DP slave station;

[0059] Based on preset process parameters, the opening degree of the first-stage pressure reducing valve 42 and the second-stage pressure reducing valve 43, as well as the on / off state of the first solenoid valve 46 and the second solenoid valve 37 are dynamically adjusted through periodic data exchange.

[0060] The gas atmosphere concentration and humidity parameters inside the muffle furnace 1 are controlled in a closed loop based on the flow signals fed back by the flow meter 44, humidity sensor, and dew point sensor.

[0061] like Figure 2 As shown, this application also provides a muffle-type bright heat treatment furnace, including a muffle furnace 1, a hydrogen main inlet pipeline 2, and the atmosphere control device.

[0062] In some embodiments of this application, the humidification tank 3 is equipped with a liquid level detector, which is electrically connected to the PLC control system and is used to monitor the liquid level of the humidification liquid in the humidification chamber in real time.

[0063] like Figure 2 As shown, the gas outlet 35 is connected to the gas inlet of the muffle furnace 1 through the gas outlet pipe 36. The gas outlet pipe 36 is equipped with a second solenoid valve 37 that is electrically connected to the PLC control system, which is used to control the gas flow rate delivered by the humidification tank 3.

[0064] like Figure 1 and Figure 2 As shown, the humidification tank 3 has a transparent observation window 38 embedded in its side wall for observing the liquid level of the humidification liquid in the humidification chamber.

[0065] like Figure 1 and Figure 2 As shown, the atmosphere control device also includes a dew point sensor connected to the PLC control system for detecting the gas dew point temperature.

[0066] In some embodiments of this application, the atmosphere control device further includes an automatic liquid replenishment device. The outlet of the automatic liquid replenishment device is connected to the liquid replenishment port 32 of the humidification storage tank 3. The control terminal of the automatic liquid replenishment device is electrically connected to the PLC control system and is used to replenish liquid into the humidification storage tank 3.

[0067] In some embodiments of this application, the automatic liquid replenishment device includes a liquid replenishment pump, which is connected to the liquid replenishment port of the humidification storage tank via a liquid replenishment pipe. A control valve is mounted on the liquid replenishment pipe and connected to the PLC controller. The humidification liquid is deionized water.

[0068] In some embodiments of this application, a humidity sensor is provided between the humidification storage tank 3 and the gas outlet pipe of the muffle furnace 1 to detect the humidity of the gas in the circulating air duct of the muffle furnace.

[0069] In actual production, when heat-treating duplex steel and super duplex steel series products, phenomena such as steel sticking, scratches, and furnace jamming are prone to occur. This application introduces gas into a humidification tank to regulate gas humidity and also introduces a dew point sensor to measure the dew point. By interlocking the atmosphere control with the real-time feedback value of the dew point, the gas atmosphere parameters and humidity in the muffle furnace are controlled, ensuring that the steel pipes radially heat-treated in the muffle furnace do not stick and that the atmosphere in the muffle furnace is not too humid, thus avoiding the phenomenon of dull steel pipes exiting the furnace for annealed steel grades. Specifically, a dew point sensor is added to the hot zone for real-time monitoring, and the real-time dew point value is fed back to the PLC controller. The PLC controller adjusts the solenoid valve to regulate the flow rate. The flow meter can then feed back the real-time flow rate to the PLC controller. The PLC controller adjusts the opening of the pressure reducing valve and / or solenoid valve according to the detection signal of the flow meter 44 to control the gas flow rate and flow into the humidification tank 3, forming a closed-loop control, thereby achieving precise control of the gas atmosphere.

[0070] Taking a 32750, φ25mm steel pipe as an example, the heat treatment temperature is 1160℃ and the hydrogen flow rate is 100Nm. 3 / h, oxygen content in the furnace <100PPM, such as Figure 4 The diagram shows the dynamic response curve of gas humidification. The horizontal axis represents the real-time dew point value in °C, and the vertical axis represents the volume of water added to the muffle furnace by the automatic replenishment device per hour in mL. When the dew point is -25°C, the atmosphere inside the furnace is prone to change during continuous heat treatment. When the dew point is <-30°C, the steel pipes are very prone to adhesion; and when the dew point temperature is >-15°C, the surface of the steel pipes turns grayish-green. Heat treatment is unqualified in both cases. Therefore, precise control is required at key points to achieve qualified results.

[0071] The above embodiments are for illustrating the implementation schemes disclosed in this invention and should not be construed as limiting the invention. Furthermore, various modifications listed herein, as well as variations in the methods and compositions of the invention, will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been specifically described in conjunction with various specific preferred embodiments, it should be understood that the invention should not be limited to these specific embodiments. In fact, various modifications as described above that are obvious to those skilled in the art to obtain the invention should be included within the scope of this invention.

Claims

1. An atmosphere control device, characterized in that, Located between the muffle furnace (1) and the main hydrogen inlet pipeline (2), it includes: A humidifying storage tank (3) defines a humidifying chamber and contains humidifying liquid. The bottom of the humidifying storage tank (3) is provided with an air inlet (31), a liquid replenishment port (32), and a liquid drain port (33) communicating with the humidifying chamber. The top of the tank is provided with a vent port (34) and an air outlet (35). The air outlet (35) is connected to the circulating air duct (11) of the muffle furnace (1) via an air outlet pipe (36). A multi-stage pressure reduction and control bypass (4) connects the main hydrogen inlet pipeline (2) and the inlet (31) of the humidification tank (3). It includes a pressure reducing pipe (41) and multiple pressure reducing valves connected in series on the pressure reducing pipe (41) to reduce the pressure of the gas transported by the main hydrogen inlet pipeline (2) to the working pressure in multiple stages.

2. The atmosphere control device according to claim 1, characterized in that: The multi-stage pressure reduction and control bypass (4) adopts a two-stage pressure reduction architecture. One end of the pressure reduction pipe (41) is connected to the main hydrogen inlet pipe (2), and the other end is connected to the inlet (31) of the humidification storage tank (3). The pressure reduction pipe (41) is equipped with a first-stage pressure reducing valve (42) and a second-stage pressure reducing valve (43) in sequence along the gas flow direction, which are used to adjust the gas transported by the main hydrogen inlet pipe (2) to the working pressure in two stages.

3. The atmosphere control device according to claim 1, characterized in that: A flow meter (44), a pointer valve (45), and a first solenoid valve (46) are also provided on the pressure reducing pipe (41) downstream of the pressure reducing valve.

4. The atmosphere control device according to claim 1, characterized in that: It also includes a PLC control system (5), which is electrically connected to the first-level pressure reducing valve (42), the second-level pressure reducing valve (43), the flow meter (44), the first solenoid valve (46), and the second solenoid valve (37) via the DP bus to form a master-slave industrial control network, used to dynamically adjust the gas atmosphere and humidity inside the muffle furnace (1); The PLC control system serves as the DP master station, and the first-stage pressure reducing valve (42), the second-stage pressure reducing valve (43), the flow meter (44), the first solenoid valve (46), and the second solenoid valve (37) serve as the DP slave stations.

5. The atmosphere control device according to claim 1, characterized in that: The gas outlet (35) is connected to the gas inlet of the muffle furnace (1) through the gas outlet pipe (36), and the gas outlet pipe (36) is equipped with a second solenoid valve (37) that is electrically connected to the PLC control system.

6. The atmosphere control device according to claim 1, characterized in that: The humidification tank (3) is equipped with a level detector connected to the PLC control system, which is used to monitor the level of the humidifying liquid in the humidification chamber in real time.

7. The atmosphere control device according to claim 1, characterized in that: The humidification tank (3) has a transparent observation window (38) embedded in its side wall for observing the liquid level of the humidification liquid in the humidification chamber.

8. The atmosphere control device according to claim 1, characterized in that: It also includes a dew point sensor that connects to the PLC control system for detecting the gas dew point temperature.

9. The atmosphere control device according to claim 1, characterized in that: It also includes an automatic liquid replenishment device, the outlet of which is connected to the liquid replenishment port (32) of the humidification tank (3) via a pipeline, and the control terminal of the automatic liquid replenishment device is electrically connected to the PLC control system for replenishing liquid into the humidification tank (3).

10. A muffle-type bright heat treatment furnace, characterized in that: It includes a muffle furnace (1), a main hydrogen inlet pipeline (2), and an atmosphere control device as described in any one of claims 1 to 9.

Images