Integral annealing method and device for large steel structure spare parts

Abstract

The invention relates to the technical field of metallurgical equipment maintenance and heat treatment, in particular to an integral annealing method and device for large steel structure spare parts. The method comprises the following steps that a steel mold is transported to a platform in a segmented mode, and an operation area is defined, isolated and sealed; assembling of segmented components is completed on the platform; an inner-layer heat preservation structure is constructed on the surface of the steel member, and a closed heat preservation cabin is formed by splicing light interlayer color steel plates on the periphery of the inner-layer heat preservation structure; an annealing device pipeline is in butt joint with a blast furnace coke gas system, and a distributed heater is arranged in an inner cavity of the component; executing programmed temperature rise; and after heat preservation is finished, fuel gas is automatically cut off, natural cooling is conducted in the cabin, and finally all temporary facilities are dismantled. By arranging the double-layer heat preservation system, heat loss is effectively reduced, and the heat efficiency is improved; the uniformity is ensured by adopting an internal heating mode; the accuracy and safety of the process are ensured by intelligent control and safety monitoring, and the technical problem of high-quality integral annealing of large components in the blast furnace casting house field is successfully solved.

Description

Technical Field

[0001] This invention relates to the field of metallurgical equipment maintenance and heat treatment technology, specifically to a method and apparatus for integral annealing of large steel structure spare parts. Background Technology

[0002] Large welded steel structural components, such as blast furnace main trough steel molds, are key equipment used in ironmaking production to support and shape refractory materials. These structures are typically characterized by their large size, heavy weight, and numerous welded joints. After long-term high-temperature service or welding, residual stress is easily generated, affecting the structural dimensional stability and service life. Therefore, annealing treatment is necessary to eliminate stress and homogenize the microstructure.

[0003] Currently, the annealing treatment for such large steel structures mainly adopts traditional segmented annealing or disassembly followed by furnace annealing. While segmented annealing can accommodate large component sizes, the heating and cooling processes of each segment are difficult to synchronize, easily leading to uneven temperature distribution throughout the component, causing residual stress redistribution or even localized stress concentration, affecting the overall uniformity of component performance. On the other hand, disassembling large structures and processing them in a fixed annealing furnace not only increases the cost and time of disassembly, transportation, and re-welding, but may also affect equipment accuracy due to secondary assembly errors, severely restricting maintenance efficiency and construction cycles. Furthermore, fixed annealing furnaces have high requirements for site conditions, cannot achieve rapid on-site processing, and are difficult to meet the needs of metallurgical enterprises for rapid maintenance of key equipment such as main troughs in continuous production.

[0004] Therefore, the existing technology lacks a process and equipment that can perform rapid, uniform, and integrated annealing of large steel structure welded spare parts under field conditions, resulting in low annealing efficiency, high energy consumption, long construction cycle, and difficulty in ensuring the consistency and stability of the overall performance of large components. Summary of the Invention

[0005] The purpose of this invention is to solve the problems of low annealing efficiency, high energy consumption, and long construction period when processing large components in the prior art.

[0006] The purpose of this invention is to provide a method and apparatus for overall annealing of large steel structure spare parts. By combining on-site utilization of blast furnace coke gas, modular double-layer insulation, and closed-loop control and safety linkage, it is possible to achieve efficient, uniform and safe stress relief of large welded components within a short maintenance window.

[0007] To achieve the above objectives, one of the objectives of this invention is to provide a method for integral annealing of large steel structure spare parts, comprising the following steps:

[0008] Step S1: Transport the prefabricated steel mold body in sections to the blast furnace tapping platform, demarcate the work area on the platform, and carry out hard isolation and safety enclosure to form a preliminary work space;

[0009] After the basic assembly of each segmented component is carried out, an airtightness test is then performed.

[0010] Step S2: Construct an inner insulation structure on the outer surface of the assembled steel components; then, assemble a detachable, sealed insulation chamber around the inner insulation structure using lightweight sandwich color steel plates.

[0011] Step S3: Connect the gas supply and induced draft pipelines of the annealing unit directly to the existing coke gas pipeline system in the blast furnace area; then arrange distributed heaters in the closed steel structure internal cavity;

[0012] Step S4: After the system pre-start and safety self-check are performed by the intelligent control component of the annealing device, the temperature is increased in a programmed manner;

[0013] Safety monitoring and emergency response were carried out throughout the annealing process. After the heat preservation stage, the system automatically cut off the gas supply, allowed natural cooling, and finally dismantled all temporary facilities.

[0014] As a further improvement to this technical solution, in step S1, on the 300H-shaped steel laid on the ground, the various segments of the main body of the steel mold are aligned, fastened, and the main welds are completed to form the overall structure to be processed.

[0015] Subsequently, a preliminary airtightness and structural stability check was conducted on the overall structure.

[0016] As a further improvement to this technical solution, in step S2, thermal insulation cotton felt is laid on the outer surface of the assembled steel component using a pre-welded suspension bracket, covering all outer surfaces and base gaps to form an inner insulation structure that is tightly attached to the component.

[0017] As a further improvement to this technical solution, in step S3, multiple sets of blast furnace coke gas burners are symmetrically arranged in the closed steel component's internal cavity.

[0018] As a further improvement to this technical solution, in step S4, the programmed heating is to set the heating rate, target temperature and holding time in the control center according to the component material and the target annealing curve.

[0019] After ignition, the system adjusts the coke gas proportioning valve and the frequency of the induced draft fan, tracks the temperature feedback of key temperature measurement points of the components in real time, and dynamically fine-tunes the combustion power to ensure that the actual heating process precisely matches the preset curve.

[0020] A second objective of this invention is to provide an integral annealing apparatus for the aforementioned integral annealing method for large steel structure spare parts, comprising:

[0021] The intelligent control component of the annealing unit serves as the control core, used for automatic process control and safety monitoring.

[0022] Sandwich-layered color steel plates are used to assemble and form a sealed outer insulation chamber;

[0023] The main body of the steel mold serves as a spare steel structure component to be annealed;

[0024] An annealing gun is arranged inside the main body of the steel mold as an internal heating source;

[0025] On-site warning tape is used to demarcate a safe area;

[0026] Insulating cotton felt is laid on the outer surface of the steel mold body as an inner insulation material.

[0027] 300H-shaped steel is laid on the ground as a load-bearing base.

[0028] As a further improvement to this technical solution, the intelligent control component of the annealing device integrates an annealing curve setting module, a process parameter acquisition module, a gas and air volume adjustment module, and a safety interlock logic control module.

[0029] As a further improvement to this technical solution, the annealing guns are connected to the on-site coke gas supply system via pipelines, and there are at least two of them, symmetrically arranged in the internal cavity of the steel mold body.

[0030] As a further improvement to this technical solution, the heat-insulating cotton felt is a multi-layer high-temperature resistant ceramic fiber heat insulation material.

[0031] As a further improvement to this technical solution, all components of the device are detachable temporary installation structures.

[0032] In this invention, a double-layer insulation system is set up to effectively reduce heat loss and improve thermal efficiency; internal heating is used to ensure uniformity; intelligent control and safety monitoring ensure the accuracy and safety of the process, and successfully solve the technical problem of high-quality overall annealing of large components at the blast furnace tapping site.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] In this method and apparatus for overall annealing of large steel structure spare parts, a double-layer dynamic insulation system consisting of an inner flexible insulation layer and an outer closed insulation chamber is constructed. Combined with direct heating inside the blast furnace coke gas and intelligent programmed temperature control, the overall uniform annealing of large steel structures in complex production sites is achieved, which improves annealing efficiency and heat treatment quality, avoids component disassembly and secondary assembly, effectively shortens the construction cycle, and utilizes on-site coke gas energy to reduce overall energy consumption and processing costs.

[0035] Furthermore, this integrated solution establishes a safe and controllable independent workspace in the high-risk continuous metallurgical production environment. Through intelligent monitoring and a safety linkage system, it effectively isolates operational risks, ensuring the safety of personnel and equipment. Its modular design and rapid assembly / disassembly capabilities give the technology excellent field adaptability, providing reliable and efficient technical support for the rapid maintenance and lifespan management of large, critical components in industries such as metallurgy and heavy equipment. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0037] Figure 2 This is a layout diagram of the steel mold annealing site for the present invention;

[0038] Figure 3 This is a front view of the on-site heat preservation measures for steel molds according to the present invention.

[0039] The meanings of the labels in the diagram are as follows:

[0040] 1. Intelligent control components for the annealing device; 2. Sandwiched color steel plate; 3. Steel mold body; 4. Annealing gun; 5. On-site warning tape; 6. Thermal insulation cotton felt; 7. 300H-section steel. Detailed Implementation

[0041] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0043] Please see Figure 1 As shown, one of the objectives of this embodiment is to provide a method for integral annealing of large steel structure spare parts, including the following steps:

[0044] Step S1: Transport the prefabricated steel mold body in 3 sections to the blast furnace tapping platform, demarcate the work area on the platform, and carry out hard isolation and safety enclosure to form a preliminary work space.

[0045] On the 300H-beams 7 laid on the ground, the various segments of the main body 3 of the steel mold were quickly aligned, tightened, and the main welds were completed to form the overall structure to be processed. Subsequently, a preliminary airtightness and structural stability check was performed on the overall structure.

[0046] Step S2: On the outer surface of the assembled steel component, use the pre-welded suspension bracket to quickly lay the thermal insulation covering cotton felt 6. The thermal insulation covering cotton felt 6 is a multi-layer high-temperature resistant ceramic fiber thermal insulation cotton felt, ensuring that it covers all outer surfaces and base gaps, forming an inner insulation structure that is close to the component and minimizes heat loss. The inner insulation structure serves as the first thermal insulation barrier.

[0047] Around the components with the inner insulation structure laid, a detachable, sealed insulation chamber is quickly assembled using lightweight sandwich color steel plates 2. This chamber not only serves as a second insulation barrier, significantly reducing environmental heat loss, but more importantly, it creates a controllable, safe operating space isolated from the external production environment on the high-risk iron tapping platform, achieving physical separation between annealing operations and surrounding production activities;

[0048] Step S3: Directly and safely connect the gas supply and induced draft pipelines of the annealing unit to the existing coke gas pipeline system in the blast furnace area. This step innovatively utilizes the readily available by-product gas on-site as a heat source, avoiding additional energy transportation and achieving on-site and efficient energy utilization.

[0049] Internal distributed heater arrangement: Multiple sets of blast furnace coke gas burners, such as annealing guns 4, are symmetrically arranged inside the enclosed steel structure. This direct internal heating method, compared with external heating, enables the temperature field of the huge structure to be transferred more evenly from the inside to the outside, fundamentally improving the heating uniformity problem from the perspective of heat source distribution;

[0050] Step S4: The system pre-start and safety self-check are performed through the intelligent control component 1 of the annealing device. Specifically, the system pre-start and safety self-check is performed by remotely starting the integrated intelligent control center. The system automatically executes a series of safety self-check procedures, including pipeline leak detection, fan status, flame monitor, gas concentration sensor, and emergency shut-off valve. After all checks are completed and confirmed to be correct, the system enters the standby ignition state.

[0051] Based on the component material and the target annealing curve, the operator sets the heating rate, target temperature, and holding time at the control center. After ignition, the system dynamically adjusts the combustion power by regulating the coke gas proportioning valve and the induced draft fan frequency, tracking the temperature feedback at key temperature measurement points of the component in real time, and ensuring that the actual heating process precisely matches the preset curve, thus achieving programmed and uniform heating.

[0052] Safety monitoring and emergency response are implemented during annealing. Throughout the annealing process, a coordinated safety network is established, consisting of a flame monitoring system, a multi-point temperature sensor network within the chamber, a CO / O2 concentration monitor with audible and visual alarms, emergency ventilation, and automatic fire suppression systems. Any abnormal parameters (such as flameout, overheating, or gas leakage) will trigger a tiered alarm and automatically execute corresponding protective measures (such as cutting off the gas supply and activating ventilation) to ensure operational safety in high-risk environments.

[0053] Controlled Cooling and System Removal: After the insulation phase, the system automatically cuts off the gas supply and enters the natural cooling phase inside the sealed chamber. Once the component temperature has safely dropped to ambient temperature, the intelligent system indicates that removal is possible. Workers then dismantle the insulation chamber, inner insulation layer, and heating pipes in sequence, restoring the site and completing the entire annealing process.

[0054] The second objective of this embodiment is to provide an integral annealing apparatus for the aforementioned integral annealing method for large steel structure spare parts, which mainly consists of the following components:

[0055] Annealing unit intelligent control component 1: As the control core of the system, it includes a remote control center, PLC or industrial computer, data acquisition module, and gas and air volume regulation actuators. It integrates annealing curve setting, real-time monitoring of process parameters, automatic adjustment control, and safety interlock logic to realize intelligent control and safety linkage in step S4.

[0056] 2. Sandwich-layer color steel plate: Used for rapid assembly to form a sealed outer insulation chamber. It is a lightweight double-layer structure with insulation material in between, and has the characteristics of heat insulation, sound insulation, fire resistance and rapid disassembly and assembly. It is a key component for achieving on-site safety isolation and secondary insulation.

[0057] Steel mold body 3: refers to the large steel structure component to be annealed, such as the steel mold for the main blast furnace trough. It is the object of annealing treatment and serves as the entire unit that bears the internal heat source and is heated in the process.

[0058] Annealing gun 4: This is a dedicated burner for blast furnace coke gas, located inside the main body of the steel mold. It is connected to the coke gas source and induced draft fan via pipelines and is the core component that converts the on-site coke gas into an internal heat source for directly heating the components.

[0059] Site warning tape 5: Used to delineate a safety warning area around the insulated chamber during annealing operations to prevent unauthorized personnel from entering and avoid safety risks such as burns and gas poisoning.

[0060] Thermal insulation felt 6: refers to multi-layer high-temperature resistant ceramic fiber thermal insulation felt, which is laid on the outer surface of the steel mold body to form an inner insulation structure that is close to the workpiece. Its main function is to reduce the radiation and convection heat loss on the surface of the workpiece.

[0061] 300H-section steel 7: Lay on the ground of the tapping platform, serving as a rigid base to support the entire steel mold body and its insulation and heating system. It ensures stable support for large components during the heating process and provides space for the laying of the bottom insulation layer.

[0062] The specific implementation steps of this invention are as follows:

[0063] Step 1: On the blast furnace tapping platform, in a stable area outside the safe distance from the main blast furnace body, lay several 300H-shaped steel sections 7 in parallel as supporting bases. The spacing is determined according to the size and weight of the main steel mold body 3 (usually 1.5-2 meters). Use a large crane to hoist the prefabricated main trench steel mold body 3, consisting of two or more sections, onto the steel bases. After alignment and tightening, use welding rods matching the base material to complete the main butt welds between each section, forming a continuous integral structure to be processed. After welding, perform an airtightness check (e.g., using the soap water test method) and a visual inspection on the overall structure.

[0064] On the outer surface of the welded steel mold body 3, a first layer of insulating cotton felt 6 is laid using pre-welded round pipe / angle steel suspension brackets. This cotton felt is made of high-temperature resistant ceramic fiber, with a single layer thickness of not less than 50mm and a total coverage thickness of not less than 100mm, ensuring tight coverage of all outer surfaces of the components and gaps between the steel sections 7. Subsequently, approximately 0.8-1.2 meters from the outer insulation layer of the components, a fully enclosed rectangular insulated work chamber is quickly constructed using lightweight fireproof laminated steel plates 2. The thickness of the steel plates is typically 50-100mm, and the joints of the chamber must be treated with high-temperature resistant sealing strips to achieve physical isolation and secondary insulation.

[0065] Connect the gas supply and induced draft pipelines of the annealing unit to the existing coke gas pipeline system in the blast furnace area via quick-connect couplings. Strict leak detection is required at the connection points. The coke gas supply pressure should be stabilized within the range of 5-15 kPa. Install at least two sets of blast furnace coke gas-specific annealing guns 4 at both ends of the internal cavity of the steel mold body 3 or at symmetrical positions along its length. The flame nozzle direction of the annealing guns should avoid directly impacting the base material and ensure smooth flow of combustion products.

[0066] Step 2: The operator uses the human-machine interface of the intelligent control component 1 of the annealing device to set a complete digital annealing temperature curve according to the material (e.g., Q235B), thickness, and annealing process requirements of the steel mold body 3. Typical curve parameters include: heating from room temperature to the target temperature at a rate of ≤80℃ / h, holding at that temperature for 4-6 hours, and then entering the natural cooling stage.

[0067] After setup, the intelligent control system is remotely activated. The system automatically executes a pre-start safety self-check sequence: checking the status and leakage of the solenoid valve in the coke gas pipeline, confirming the normal operation of the induced draft fan, verifying the flame detector and thermocouple circuit, and checking the baseline values ​​of the O2 / CO gas concentration sensors inside the chamber. After all self-check items pass, the system enters the "ready to ignite" state. At the same time, a site warning tape is set up three meters around the perimeter of the insulated work chamber, and safety warning signs are set up.

[0068] Step 3: The operator issues the ignition command. The intelligent control component 1 of the annealing device starts the induced draft fan, opens the solenoid valve of the main coke gas pipeline, and ignites the igniter of the annealing gun 4 according to the preset program. After the flame monitoring system confirms that the flames of all gun heads are stable, the main combustion program is started.

[0069] During the heating phase, the system enters a closed-loop control mode. Multiple K-type thermocouples, located inside the main body of the steel mold 3 and at key locations on its outer surface (such as weld areas and thick sections), feed real-time temperature data back to the intelligent control component 1. The controller compares the measured average temperature with the preset temperature rise curve. Through a built-in PID (proportional-integral-derivative) algorithm, it dynamically adjusts the opening of the coke gas proportional regulating valve and the frequency of the induced draft fan inverter, thereby precisely controlling the flow rate and combustion power of the mixed gas. This ensures that the overall temperature rise of the component strictly follows the set curve, guaranteeing heating uniformity and preventing localized overheating or excessively rapid temperature rise.

[0070] Step 4: Throughout the annealing process, the safety monitoring network integrated by the intelligent control component 1 of the annealing unit operates continuously. This system monitors the flame status, temperature at various points, CO concentration (set alarm threshold ≤ 24 ppm), and O2 concentration (set alarm threshold ≥ 19.5%) within the insulation chamber in real time. Any abnormal parameter (such as flame extinguishing, temperature exceeding the upper limit at any point, or CO concentration exceeding the standard) will immediately trigger an audible and visual alarm and execute tiered interlocking protection: In the case of a Level 1 alarm, the system automatically adjusts the gas flow in an attempt to restore normal operation; if the parameters remain abnormal and reach the Level 2 alarm threshold, the system will immediately and urgently shut off the main coke gas valve, start the emergency exhaust fan, and send an alarm message to the monitoring center.

[0071] When the system detects that the heat preservation stage is complete, it automatically shuts off the coke gas supply, extinguishes the annealing gun 4, and ends the heating stage. The system maintains the closed state of the heat preservation chamber, allowing the steel mold body 3 to cool naturally in a double-layer heat preservation environment. The cooling rate is usually controlled at ≤50℃ / h (for stages above 300℃). The intelligent control component 1 of the annealing device continuously monitors the temperature until the temperature at all points of the component drops below the safe temperature, at which point it issues a "cooling complete, disassembly can proceed" prompt.

[0072] After receiving the notification, the workers first ventilated the cabin to ensure the air quality was safe. Then, they removed the sandwiched color steel plate 2 insulation chamber, removed the insulation covering cotton felt 6, disconnected and removed the annealing gun 4 and pipelines, and finally lifted the steel mold body 3 that had been annealed to restore the site.

[0073] In summary, through the organic connection and synergistic effect of the above four steps, this invention constructs a comprehensive on-site overall annealing system that integrates "rapid on-site assembly, local energy utilization, multi-layer dynamic insulation, internal distributed heating, intelligent and precise temperature control, and full-process safety monitoring," effectively solving the problem of efficient, uniform, and safe heat treatment of large welded steel structures in high-risk, continuous production metallurgical industrial sites.

[0074] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for integral annealing of large steel structure spare parts, characterized in that, Includes the following steps: Step S1: Transport the prefabricated steel mold body (3) in sections to the blast furnace tapping platform, demarcate the work area on the platform, carry out hard isolation and safety enclosure to form a preliminary work space; After the basic assembly of each segmented component is carried out, an airtightness test is then performed. Step S2: Construct an inner insulation structure on the outer surface of the assembled steel components; Then, a detachable, sealed insulation chamber is formed by assembling lightweight sandwich color steel plates (2) around the outer layer of the inner insulation structure. Step S3: Connect the gas supply and induced draft pipelines of the annealing unit directly to the existing coke gas pipeline system in the blast furnace area; then arrange distributed heaters in the closed steel structure internal cavity; Step S4: After the system pre-start and safety self-check are performed by the intelligent control component (1) of the annealing device, the temperature is increased in a programmed manner; Safety monitoring and emergency response were carried out throughout the annealing process. After the heat preservation stage, the system automatically cut off the gas supply, allowed natural cooling, and finally dismantled all temporary facilities.

2. The method for integral annealing of large steel structure spare parts according to claim 1, characterized in that: In step S1, on the 300H-shaped steel (7) laid on the ground, the various segments of the main body of the steel mold (3) are aligned, fastened and the main welds are completed to form the overall structure to be processed. Subsequently, a preliminary airtightness and structural stability check was conducted on the overall structure.

3. The method for integral annealing of large steel structure spare parts according to claim 1, characterized in that: In step S2, thermal insulation felt (6) is laid on the outer surface of the assembled steel component using a pre-welded suspension bracket to cover all outer surfaces and base gaps, forming an inner thermal insulation structure that is tightly attached to the component.

4. The method for integral annealing of large steel structure spare parts according to claim 1, characterized in that: In step S3, multiple sets of blast furnace coke gas burners are symmetrically arranged inside the closed steel component cavity.

5. The method for integral annealing of large steel structure spare parts according to claim 1, characterized in that: In step S4, programmed heating is achieved by setting the heating rate, target temperature, and holding time in the control center according to the component material and the target annealing curve. After ignition, the system adjusts the coke gas proportioning valve and the frequency of the induced draft fan, tracks the temperature feedback of key temperature measurement points of the components in real time, and dynamically fine-tunes the combustion power to ensure that the actual heating process precisely matches the preset curve.

6. An integral annealing apparatus for the integral annealing method for large steel structure spare parts as described in any one of claims 1-5, characterized in that, include: The intelligent control component (1) of the annealing device serves as the control core and is used for automatic process control and safety monitoring. Sandwich color steel plate (2) is used to assemble a sealed outer heat preservation chamber; The main body of the steel mold (3) serves as a spare steel structure to be annealed; An annealing gun (4) is arranged inside the steel mold body (3) as an internal heating source; On-site warning tape (5) is used to delineate a safe area; Insulating cotton felt (6) is laid on the outer surface of the steel mold body (3) as an inner insulation material; 300H steel (7) is laid on the ground as a support base.

7. The integral annealing apparatus according to claim 6, characterized in that: The intelligent control component (1) of the annealing device integrates an annealing curve setting module, a process parameter acquisition module, a gas and air volume adjustment module, and a safety interlock logic control module.

8. The integral annealing apparatus according to claim 7, characterized in that: The annealing gun (4) is connected to the on-site coke gas supply system through a pipe, and there are at least two of them, which are symmetrically arranged in the internal cavity of the steel mold body (3).

9. The integral annealing apparatus according to claim 7, characterized in that: The heat-insulating cotton felt (6) is a multi-layer high-temperature resistant ceramic fiber heat insulation material.

10. The integral annealing apparatus according to claim 7, characterized in that: All components of the device are detachable temporary installation structures.

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