Intelligent rapid circulating cooling system and method for large vacuum sintering furnace

Abstract

The invention provides an intelligent rapid circulating cooling system and method for a large vacuum sintering furnace, and relates to the technical field of vacuum furnaces. The system comprises a furnace shell; a steel frame is arranged in the furnace shell, a carbon felt is fixed on the inner side of the steel frame, and a graphite plate is arranged in the carbon felt; a heating body group is arranged in the graphite plate; a rapid circulation cooling device is arranged outside the steel frame, and a snakelike cooling pipe is embedded in the outer surface of the rapid circulation cooling device; an inlet of the S-shaped cooling pipe is connected with a liquid inlet pipeline penetrating through the furnace shell, and an outlet is connected with a liquid return pipeline penetrating through the furnace shell; a vortex shedding flowmeter and a temperature sensor are arranged on the liquid inlet pipeline, an electric control valve and a temperature sensor are arranged on the liquid inlet pipeline, and the furnace shell is in compression connection with the furnace door to form a closed vacuum working chamber; and the vortex shedding flowmeter, the temperature sensor and the electric control valve are all in communication connection with the central controller. The cooling efficiency and the temperature uniformity are effectively improved, the energy consumption and the maintenance cost are reduced, and the large-scale furnace batch production requirement is met.

Description

Technical Field

[0001] This invention relates to the field of vacuum furnace technology, and in particular to an intelligent rapid circulating cooling system and method for a large vacuum sintering furnace. Background Technology

[0002] In the field of materials processing, vacuum sintering furnaces, with their advantages of controllable high temperature and pure atmosphere, have become an indispensable core equipment in processes such as metal heat treatment, ceramic densification, and high-reliability brazing. After completing high-temperature sintering, vacuum sintering furnaces require a long cooling process. The cooling stage is a key factor that determines the microstructure, residual stress, and final properties, and is also a bottleneck restricting production capacity and energy consumption.

[0003] Currently, cooling methods are mainly divided into: natural cooling, forced gas cooling, and liquid cooling. Natural cooling relies on the furnace body's natural heat dissipation without an additional power source, but its cooling efficiency is low, often requiring tens of hours or even days to lower the temperature to the furnace opening temperature, severely reducing production efficiency and making it difficult to meet the time-sensitive requirements of mass production. Because the cooling rate of natural cooling lacks controllability, the cooling curve cannot be guaranteed, and the temperature uniformity and thermal stress of the workpiece cannot be effectively controlled, leading to a decline in workpiece quality. Furthermore, this heat energy is not recovered and utilized in a timely and effective manner, resulting in energy waste. Forced gas cooling often uses inert gases such as nitrogen as the cooling medium, with a fan driving the gas to circulate and exchange heat within the furnace. The cooling rate is significantly improved compared to natural cooling, but due to the low thermal conductivity of gases, its heat exchange efficiency still needs improvement. Additionally, limitations imposed by the size of the vacuum sintering furnace cavity and the power of the fan prevent its application in large-scale vacuum sintering furnaces. Liquid cooling can achieve higher cooling efficiency in specific scenarios due to the high thermal conductivity of liquids. However, the heat exchange efficiency of liquid cooling is greatly affected by the medium flow rate and temperature gradient. Existing control methods are difficult to achieve precise dynamic regulation, which can easily lead to local cooling that is too fast or too slow. This can cause uneven heating of the workpiece during the cooling process, resulting in thermal stress.

[0004] Chinese patent application number 202110513801.8, entitled "A Water Circulation Cooling System for a Vacuum Sintering Furnace," proposes a water circulation system for a vacuum sintering furnace. This system uses a combination of water-cooled coils and fans for heat dissipation, but its overall heat exchange capacity is limited, making it difficult to meet the heat dissipation requirements of large vacuum sintering furnaces. Furthermore, the system lacks the ability to dynamically adjust the cooling rate, making it difficult to achieve high-quality cooling. Meanwhile, Chinese patent application number 202411762028.9, entitled "An Intelligent Control System and Control Method for Cooling a Vacuum High-Temperature Furnace," proposes a system that provides threshold warnings for parameters such as temperature and flow rate, but lacks real-time thermal stress calculation and risk assessment capabilities, making it unable to predict workpiece quality risks in advance and exhibiting delayed abnormal response.

[0005] In summary, existing cooling technologies for large vacuum sintering furnaces still have significant shortcomings in terms of cooling rate, temperature uniformity, and intelligent control, making it difficult to meet the needs of actual production. Therefore, designing an intelligent rapid circulation cooling system for large vacuum sintering furnaces that combines speed, uniformity, and intelligent control capabilities is of great practical significance for improving product quality and production efficiency. Summary of the Invention

[0006] To address the shortcomings of the existing technologies, this invention proposes an intelligent rapid circulation cooling system for large-scale vacuum sintering furnaces based on a cooling method that couples phase change materials with liquid cooling. This system aims to solve the technical problems of low cooling efficiency and high control difficulty in existing large-scale vacuum sintering furnaces, effectively improving cooling efficiency and temperature uniformity, reducing energy consumption and maintenance costs, and adapting to the needs of large-scale furnace mass production.

[0007] On the one hand, the present invention proposes an intelligent rapid circulation cooling system for a large vacuum sintering furnace, which includes: furnace shell, steel frame, carbon felt, graphite plate, heating element assembly, rapid circulation cooling device, serpentine cooling pipe, vortex flow meter, K-type armored thermocouple temperature sensor, electric regulating valve, furnace door and central controller.

[0008] The furnace shell is equipped with a steel frame, and a carbon felt is fixed inside the steel frame; the graphite plate is installed inside the carbon felt; the heating element assembly is installed inside the graphite plate; the rapid circulation cooling device is installed outside the steel frame; the serpentine cooling pipe is embedded on the outer surface of the rapid circulation cooling device; the inlet of the serpentine cooling pipe is connected to a liquid inlet pipe that penetrates the furnace shell; the outlet of the serpentine cooling pipe is connected to a liquid return pipe that penetrates the furnace shell.

[0009] The vortex flow meter is installed on the inlet pipe to monitor the flow rate of the cooling medium in the inlet pipe in real time; the electric regulating valve is installed on the inlet pipe to regulate the flow rate of the cooling medium in the inlet pipe; both the inlet pipe and the return pipe are equipped with type K armored thermocouple temperature sensors.

[0010] The furnace door is pressed tightly against the furnace shell to form a sealed vacuum working chamber;

[0011] The central controller is communicatively connected to the vortex flow meter, the k-type armored thermocouple temperature sensor, and the electric regulating valve.

[0012] Furthermore, the rapid circulating cooling device is internally encapsulated with a phase change material; the phase change material is used to absorb heat inside the steel frame; according to the type of phase change material, the rapid circulating cooling device is divided into two types of structures: a first type of rapid circulating cooling device based on solid-solid phase change material and a second type of rapid circulating cooling device based on solid-liquid phase change material.

[0013] The first type of rapid circulation cooling device includes: a cooling plate shell, an O-ring elastic metal sealing ring, a cooling plate base plate, fixing bolts, and sealing bolts;

[0014] The cooling plate outer shell is a shell with an inner cavity, and the inner cavity of the cooling plate outer shell is filled with a solid-solid phase change material; the outer surface of the cooling plate outer shell is provided with a cooling groove for embedding a serpentine cooling tube; the cooling plate bottom plate is attached to the cooling plate outer shell; an O-ring elastic metal sealing ring is provided between the contact surface of the cooling plate outer shell and the cooling plate bottom plate, and the connection is fastened by sealing bolts; the cooling plate outer shell is also fixedly mounted on a steel frame by fixing bolts.

[0015] The second type of rapid circulation cooling device includes: a cooling plate shell, an O-ring elastic metal sealing ring, a cooling plate base plate, fixing bolts, sealing bolts, a honeycomb phase change material receiving plate, and an expanded graphite pressure plate;

[0016] Each independent cavity of the honeycomb phase change material receiving plate is filled with a fixed amount of solid-liquid phase change material; the cooling plate shell is a shell with an inner cavity, and the filled honeycomb phase change material receiving plate is installed in the inner cavity of the cooling plate shell; the expanded graphite pressure plate is aligned and assembled with the open end of the honeycomb phase change material receiving plate; the outer surface of the cooling plate shell is provided with a cooling groove for embedding serpentine cooling pipes; the cooling plate bottom plate is attached to the cooling plate shell; an O-ring elastic metal sealing ring is provided between the contact surface of the cooling plate shell and the cooling plate bottom plate, and is fastened by sealing bolts; the cooling plate shell is also fixedly mounted on a steel frame by fixing bolts.

[0017] Furthermore, the serpentine cooling pipe is composed of several groups of partitioned serpentine cooling pipes arranged along the axial direction of the furnace body; each group of partitioned serpentine cooling pipes includes independently controllable: a first partitioned serpentine cooling pipe and a second partitioned serpentine cooling pipe.

[0018] For any one of the first and second zone serpentine cooling pipes, the inlet of the serpentine cooling pipe is connected to a liquid inlet pipe via a KF flange; the outlet of the serpentine cooling pipe is connected to a liquid return pipe via a KF flange; each serpentine cooling pipe, together with the liquid inlet pipe and the liquid return pipe connected to it, constitutes an independent cooling medium transport path.

[0019] Furthermore, a number of platinum resistance temperature sensors are provided between the steel frame and the cooling plate base plate along the axial direction of the vacuum furnace; the platinum resistance temperature sensors are used to acquire the temperature of the steel frame wall; wherein the steel frame wall temperature includes: the real-time temperature value of each monitoring point on the outer wall of the steel frame, the temperature gradient along the axial direction of the vacuum furnace, and the temperature distribution data of the steel frame wall.

[0020] Furthermore, the intelligent rapid circulation cooling system for a large vacuum sintering furnace further includes: a waste heat recovery subsystem; the inlet of the waste heat recovery subsystem is connected to the outlet of the return liquid pipe for receiving the cooling medium flowing out through the return liquid pipe; the waste heat recovery subsystem is communicatively connected to the central controller for dynamically distributing the received cooling medium.

[0021] Furthermore, the central controller includes:

[0022] The parameter initialization module is used to obtain the workpiece parameters of the sintered workpiece and match the target cooling rate curve of the sintered workpiece from the cooling rate curve database based on the workpiece parameters.

[0023] The cooling strategy matching module is used to initialize and start the intelligent rapid circulation cooling system of the large vacuum sintering furnace based on the target cooling rate curve.

[0024] The real-time online detection module is used to monitor the operating status parameters of the intelligent rapid circulation cooling system of the large vacuum sintering furnace in real time.

[0025] A multi-level intelligent control module is used to dynamically adjust the cooling medium flow rate during the cooling process based on the target cooling rate curve and the operating status parameters, using a preset multi-level control strategy.

[0026] The waste heat recovery control module is used to monitor the temperature of the cooling medium flowing out through the return liquid pipe in real time during the cooling process and use it as the waste heat temperature. Based on the waste heat temperature and the preset priority strategy, it dynamically decides the waste heat distribution path.

[0027] An abnormality protection module is used to trigger the abnormality protection when an abnormality is detected during the cooling process; and to terminate the cooling process when the cooling process reaches a preset termination condition or when the abnormality mechanism triggers a shutdown.

[0028] The post-cooling strategy optimization module is used to record the actual cooling rate curve of this cooling process after the cooling process is completed. By performing deviation analysis on the actual cooling rate curve and the target cooling rate curve, the cooling rate curve database and multi-level control strategy are updated.

[0029] On the other hand, this invention proposes an intelligent rapid circulating cooling method for a large-scale vacuum sintering furnace, which includes the following process:

[0030] Obtain the workpiece parameters of the sintered workpiece, and match the target cooling rate curve of the sintered workpiece from the cooling rate curve database based on the workpiece parameters.

[0031] Based on the target cooling rate curve, initialize and start the intelligent rapid circulation cooling system of the large vacuum sintering furnace;

[0032] During the cooling process, the operating status parameters of the system are monitored in real time, and the cooling medium flow rate is dynamically adjusted according to the target cooling rate curve and the operating status parameters using a preset multi-level control strategy.

[0033] During the cooling process, the temperature of the cooling medium flowing out through the return pipe is monitored in real time and used as the waste heat temperature. Based on the waste heat temperature and the preset priority strategy, the waste heat distribution path is dynamically determined.

[0034] When an abnormal situation is detected during the cooling process, the abnormality protection mechanism is triggered; when the cooling process reaches the preset termination condition or the abnormality protection mechanism triggers a shutdown, the cooling process is terminated.

[0035] After the cooling process is completed, the actual cooling rate curve of this cooling process is recorded. By performing deviation analysis between the actual cooling rate curve and the target cooling rate curve, the cooling rate curve database and multi-level control strategy are updated.

[0036] Furthermore, the specific content of obtaining the workpiece parameters of the sintered workpiece and matching the target cooling rate curve of the sintered workpiece from the cooling rate curve database based on the workpiece parameters is as follows:

[0037] For any sintered workpiece, obtain the workpiece parameters; wherein the workpiece parameters include: workpiece shape parameters, workpiece size parameters, tooling method parameters, and material property parameters.

[0038] The workpiece parameters are standardized to obtain workpiece parameter codes;

[0039] Using the workpiece parameter code as the search criteria, a search is performed in a preset cooling rate curve database;

[0040] If a cooling rate curve corresponding to the workpiece parameter code exists in the cooling rate curve database, then the cooling rate curve is directly called as the target cooling rate curve for the sintered workpiece.

[0041] If the cooling rate curve database does not contain a cooling rate curve corresponding to the workpiece parameter code, the workpiece parameter code is input into a pre-trained random forest regression model for prediction to generate the target cooling rate curve for the sintered workpiece.

[0042] Furthermore, the specific details of dynamically adjusting the cooling medium flow rate during the cooling process using a preset multi-level control strategy, with the target cooling rate curve as the adjustment target and the operating status parameters as the basis, are as follows:

[0043] The operating status parameters of the intelligent rapid circulation cooling system of the large vacuum sintering furnace are monitored in real time; wherein the operating status parameters include: steel frame wall temperature, cooling medium temperature and cooling medium flow rate;

[0044] Based on real-time acquired operating status parameters, real-time thermal stress is calculated. If the real-time thermal stress exceeds the maximum thermal stress threshold, an abnormal protection mechanism is triggered. If the real-time thermal stress does not exceed the maximum thermal stress threshold, each zone of the serpentine cooling pipe is considered a temperature-controlled zone, and the temperature difference between any two adjacent temperature-controlled zones is calculated. ;

[0045] When there is a temperature difference between any two adjacent temperature control zones When the flow rate is high, zone coordination control is executed to regulate the flow rate of the cooling medium during the cooling process; conversely, intelligent rate control is executed to regulate the flow rate of the cooling medium during the cooling process.

[0046] The specific content of the partition coordination control is as follows:

[0047] For any temperature control zone, calculate the target flow rate for that temperature control zone, and adjust the cooling medium flow rate of that temperature control zone to the calculated target flow rate by adjusting the opening of the electric regulating valve.

[0048] Each preset control cycle Real-time calculation of the temperature difference between every two adjacent temperature control zones. If the temperature difference of all adjacent temperature control zones If so, then the partition coordination control ends and intelligent rate control is executed; if continuously... Even after one control cycle, there is still a temperature difference between any two adjacent temperature control zones. If so, the adjustment coefficient is increased according to the preset ratio, and the real-time thermal stress is recalculated and compared with the maximum thermal stress threshold.

[0049] The specific details of the intelligent rate control are as follows:

[0050] The real-time cooling rate is calculated based on the steel frame wall temperature, and then the cooling rate deviation is calculated based on the target cooling rate curve.

[0051] When the difference between the cooling rate deviation and the set deviation is within the preset fine-tuning range, the PID control algorithm is used to calculate and adjust the cooling medium flow rate; otherwise, the cooling medium flow rate is adjusted according to the preset adjustment rules.

[0052] After adjusting the flow rate of the cooling medium, the real-time thermal stress is recalculated. If the recalculated real-time thermal stress meets the safety condition judgment conditions, intelligent rate control continues until the cooling process ends; otherwise, the abnormal mechanism protection is triggered.

[0053] Furthermore, the method for updating the cooling rate curve database and multi-level control strategy by performing deviation analysis on the actual cooling rate curve and the target cooling rate curve is as follows:

[0054] Outlier removal and time alignment were performed on the steel frame wall temperature and cooling medium flow rate collected in time series to obtain time-synchronized steel frame wall temperature and cooling medium flow rate.

[0055] Based on the axial position of the furnace body, the furnace body is divided into a high-temperature zone, a medium-temperature zone, and a low-temperature zone;

[0056] Based on the time-synchronized steel frame wall temperature and cooling medium flow rate, the initial point of deviation between the actual cooling rate curve and the target cooling rate curve is determined, and the deviation start time, initial temperature and cooling rate difference corresponding to the initial point of deviation are obtained.

[0057] Starting from the initial deviation point, the real-time deviation values ​​of several deviation points are calculated at fixed time intervals to form a time-series deviation sequence;

[0058] By fitting the time-series deviation sequence, the deviation type of the actual cooling rate curve is determined to be either gradual deviation or abrupt deviation, and a cooling process calibration operation is performed according to the deviation type of the actual cooling rate curve.

[0059] Based on the time-series deviation sequence, the average deviation of the high-temperature zone, the average deviation of the medium-temperature zone, and the average deviation of the low-temperature zone are calculated respectively, and a deviation heatmap is generated based on the calculation results.

[0060] By comparing the overall trends of the actual cooling rate curve and the target cooling rate curve, and combining the deviation type and deviation heatmap of the actual cooling rate curve, the actual cooling rate curve is corrected, and the corrected actual cooling rate curve is used to update the cooling rate curve database and multi-level control strategy.

[0061] The beneficial effects of adopting the above technical solution are as follows:

[0062] To address the problems of low cooling efficiency and limited production capacity in large vacuum sintering furnaces, this invention introduces phase change materials and combines them with a modular cooling structure using serpentine cooling pipes. This enables rapid absorption and removal of heat during the cooling stage, significantly shortening cooling time, improving production efficiency, and meeting the timeliness requirements of mass production.

[0063] The system of this invention adopts a cooling method that couples phase change materials with liquid cooling. Its cooling structure is modularly designed to achieve the synergy of the "latent heat of phase change + forced liquid cooling" dual mechanism, thereby improving the technical problem of low cooling efficiency of large furnaces that rely solely on liquid cooling or gas cooling.

[0064] The system of this invention solves the problem of uneven axial temperature distribution during the cooling process of a large vacuum sintering furnace by using a zoned precise temperature control design, thus avoiding the risk of local workpiece cracking.

[0065] This invention's system significantly reduces installation and maintenance costs through its modular and detachable design. Installation is simple: just align the rapid cooling system with the pre-drilled threaded holes in the steel frame using fasteners. During maintenance, if a cooling unit malfunctions, the entire system can be replaced individually, significantly reducing maintenance time. Furthermore, the modular design supports future upgrades and allows for flexible configuration to suit different furnace types and process requirements.

[0066] The system of this invention utilizes a data-driven multi-level intelligent control module. The system can calculate temperature uniformity and thermal stress based on real-time collected parameters such as temperature and flow rate, dynamically adjust the cooling strategy, achieve precise tracking of cooling rate and automatic response to anomalies, and improve process stability and safety.

[0067] This invention systematically constructs a safe cooling rate curve library driven by a "cooling rate-thermal stress" model, and uses self-learning to perform deviation analysis, iteratively update safe control parameters, and update the optimal cooling rate curve. In other words, by recording the deviation between the actual cooling curve and the theoretical model, the system continuously optimizes control parameters and cooling strategies, forming a closed-loop feedback mechanism. This drives continuous process iteration and upgrades to adapt to more complex or demanding tasks. The system also prioritizes waste heat recovery based on its value, achieving dynamic allocation.

[0068] In summary, this invention system design comprises two parts: structural design and intelligent control. Structurally, it employs a modular cooling design using solid-solid or solid-liquid phase change materials. Utilizing the significant heat absorption and thermal switching characteristics during the phase change process, coupled with partitioned serpentine cooling tubes, it achieves rapid cooling and uniform temperature control. For intelligent control, it first matches the cooling rate curve and initializes resources. During cooling, it collects temperature and flow data in real time to calculate temperature uniformity and thermal stress. It then uses partitioned regulation and intelligent rate control for dynamic parameter adjustment and temperature control. It also includes waste heat recovery and anomaly protection, and iteratively optimizes the strategy after cooling. Attached Figure Description

[0069] Figure 1 This is a schematic diagram of the structure of an intelligent rapid circulation cooling system for a large vacuum sintering furnace in this embodiment;

[0070] Figure 2 This is a structural disassembly diagram of the first type of rapid-cycle cooling device based on solid-solid phase change materials in this embodiment;

[0071] Figure 3 This is a cross-sectional view of the first type of rapid-cycle cooling device based on solid-solid phase change materials in this embodiment;

[0072] Figure 4 This is a cloud map showing the temperature distribution inside the vacuum sintering furnace and the insulation layer in this embodiment;

[0073] Figure 5 This is a structural disassembly diagram of the second type of rapid circulating cooling device based on solid-liquid phase change materials in this embodiment;

[0074] Figure 6 This is a cross-sectional view of the second type of rapid circulating cooling device based on solid-liquid phase change materials in this embodiment;

[0075] Figure 7 This is a schematic diagram of the honeycomb phase change material receiving plate in this embodiment;

[0076] Figure 8 This is a schematic diagram of the installation of the rapid circulation cooling device in this embodiment;

[0077] Figure 9 This is a schematic diagram of the partitioned serpentine cooling pipe structure in this embodiment;

[0078] Figure 10 This is a control workflow diagram of the central controller described in this embodiment;

[0079] Figure 11 This is a flowchart of an intelligent rapid circulating cooling method for a large vacuum sintering furnace in this embodiment;

[0080] Figure 12 This is a flowchart illustrating the process of obtaining the cooling rate curve of the vacuum sintering furnace in this embodiment.

[0081] Figure 13 This is a flowchart of the intelligent control process in this embodiment;

[0082] Figure 14 This is a flowchart of the waste heat recovery process in this embodiment;

[0083] Figure 15 This is a flowchart of the post-optimization process in this embodiment;

[0084] In the diagram: 1-furnace shell, 2-steel frame, 3-carbon felt, 4-graphite plate, 5-heating body assembly, 6-rapid circulation cooling device, 601-cooling plate outer shell, 602-O-type elastic metal sealing ring, 603-cooling plate bottom plate, 604-fixing bolt, 605-sealing bolt, 606-honeycomb phase change material receiving plate, 607-expanded graphite plate, 7-serpentine cooling pipe, 701-first zone serpentine cooling pipe, 702-second zone serpentine cooling pipe, 8-liquid inlet pipe, 9-liquid return pipe, 10-vortex flow meter, 11-K-type armored thermocouple temperature sensor, 12-electric regulating valve, 13-furnace door. Detailed Implementation

[0085] To facilitate understanding of this application, specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments. The following embodiments are illustrative of the invention but are not intended to limit its scope. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0086] Example 1:

[0087] This embodiment describes an intelligent rapid circulation cooling system for a large vacuum sintering furnace, such as... Figure 1 As shown, the system includes: furnace shell 1, steel frame 2, carbon felt 3, graphite plate 4, heating element assembly 5, rapid circulation cooling device 6, serpentine cooling pipe 7, vortex flow meter 10, type K armored thermocouple temperature sensor 11, electric regulating valve 12, furnace door 13, and central controller.

[0088] The furnace shell 1 is provided with a steel frame 2, and a carbon felt 3 is fixed inside the steel frame 2; a graphite plate 4 is installed inside the carbon felt 3; a heating element assembly 5 is installed inside the graphite plate 4; a rapid circulation cooling device 6 is installed outside the steel frame 2; a serpentine cooling pipe 7 is embedded on the outer surface of the rapid circulation cooling device 6; the inlet of the serpentine cooling pipe 7 is connected to a liquid inlet pipe 8 that penetrates the furnace shell 1; and the outlet of the serpentine cooling pipe 7 is connected to a liquid return pipe 9 that penetrates the furnace shell 1.

[0089] The vortex flow meter 10 is installed on the inlet pipe 8 to monitor the flow rate of the cooling medium in the inlet pipe 8 in real time; the electric regulating valve 12 is installed on the inlet pipe 8 to regulate the flow rate of the cooling medium in the inlet pipe 8; both the inlet pipe 8 and the return pipe 9 are equipped with k-type armored thermocouple temperature sensors 11.

[0090] It should be noted that the return pipe 9 is also equipped with a vortex flow meter 10 and an electric regulating valve 12, which are used to monitor abnormal situations in the cooling process in real time, and play a role in safety and auxiliary monitoring.

[0091] The furnace door 13 is pressed tightly against the furnace shell 1 to form a sealed vacuum working chamber.

[0092] The central controller is communicatively connected to the vortex flow meter 10, the k-type armored thermocouple temperature sensor 11, and the electric regulating valve 12.

[0093] The rapid circulating cooling device 6 is internally encapsulated with a phase change material; the phase change material is used to absorb heat inside the steel frame 2; according to the type of phase change material, the rapid circulating cooling device 6 is divided into two types of structures: a first type of rapid circulating cooling device based on solid-solid phase change material and a second type of rapid circulating cooling device based on solid-liquid phase change material.

[0094] In this embodiment, the solid-solid phase change material remains solid throughout the phase change process, undergoing only crystal structure reorganization or crystal morphology adjustment, with no risk of liquid medium leakage. Therefore, no additional sealed container or leak-proof structure is required, making it suitable for the cleanliness requirements of large vacuum sintering furnaces. Its volume expansion rate during phase change is typically lower than [missing information]. It requires no extra volume compensation space and can be tightly filled into the complex cavities or gaps of the cooling system, avoiding material cracking or structural deformation caused by drastic volume changes. At the same time, it reduces heat transfer gaps to improve heat exchange efficiency. Moreover, the material has strong phase change reversibility. After more than a thousand phase change cycles, the latent heat decay rate of the phase change has changed little. It has stable chemical properties and is not easy to decompose or age. It can maintain stable heat storage and temperature control capabilities for a long time, significantly reducing the replacement frequency and maintenance cost of phase change materials in the cooling system, and taking into account system operation safety, structural adaptability and long-term economy.

[0095] like Figure 2 and Figure 3 As shown, the first type of rapid circulation cooling device includes: a cooling plate housing 601, an O-ring elastic metal sealing ring 602, a cooling plate base plate 603, fixing bolts 604, and sealing bolts 605.

[0096] The cooling plate outer shell 601 is a shell with an inner cavity, and the inner cavity of the cooling plate outer shell 601 is filled with a solid-solid phase change material; the outer surface of the cooling plate outer shell 601 is provided with a cooling groove for embedding the serpentine cooling pipe 7; the cooling plate bottom plate 603 is attached to the cooling plate outer shell 601; an O-ring elastic metal sealing ring 602 is provided between the contact surface of the cooling plate outer shell 601 and the cooling plate bottom plate 603, and is fastened by a sealing bolt 605; the cooling plate outer shell 601 is also fixedly mounted on the steel frame 2 by fixing bolts 604.

[0097] In this embodiment, the core components of the first type of rapid circulating cooling device based on solid-solid phase change material include: a cooling plate shell 601, a solid-solid phase change material, a cooling plate base plate 603, and an O-ring elastic metal sealing ring 602. Specifically, the cooling plate shell 601 has its cooling tank and assembly structure pre-designed during the manufacturing stage, and has reserved mounting holes for water-cooled electrodes, mounting holes for connecting to the steel frame 2, and a coke discharge port for coke discharge. The solid-solid phase change material is filled into the pre-designed cavity space inside the cooling plate shell 601 through the open end, and a space is reserved during filling. The volume compensation space is provided to accommodate the volume expansion of the material during the phase change process, preventing system structural deformation or material cracking due to volume expansion and contraction. To ensure the long-term stable use of the solid-solid phase change material, a sealing design is adopted with a metal shell and sealing bolts 605, and an O-ring elastic metal sealing ring 602 is installed between the mating surfaces of the cooling plate base plate 603 and the cooling plate shell 601 (e.g., Figure 4 As shown, it fits the outer wall of steel frame 2. High temperature and excellent elastic deformation capacity (to fill the sealing gap) ensure that there is no gap between the mating surfaces of the cooling plate outer shell 601 and the cooling plate base plate 603, thereby avoiding the influence of the external environment on the phase change material. Sealing bolts 605 penetrate the pre-drilled mounting holes on the cooling plate base plate 603 and the cooling plate outer shell 601, applying uniform circumferential pressure to achieve a complete sealing connection. After sealing, the mounting surfaces of the cooling plate base plate 603 and the cooling plate outer shell 601 remain flush, ensuring a neat system appearance and providing a flat assembly reference for subsequent overall installation to the preset position on the steel frame 2, avoiding assembly gaps or structural stress caused by uneven mounting surfaces.

[0098] like Figure 5 and Figure 6 As shown, the second type of rapid circulation cooling device includes: a cooling plate housing 601, an O-ring elastic metal sealing ring 602, a cooling plate base plate 603, fixing bolts 604, sealing bolts 605, a honeycomb phase change material receiving plate 606, and an expanded graphite pressure plate 607.

[0099] Each independent cavity of the honeycomb phase change material receiving plate 606 is filled with a fixed amount of solid-liquid phase change material; the cooling plate shell 601 is a shell with an inner cavity, and the filled honeycomb phase change material receiving plate 606 is installed in the inner cavity of the cooling plate shell 601; the expanded graphite pressure plate 607 is aligned and assembled with the open end of the honeycomb phase change material receiving plate 606; the outer surface of the cooling plate shell 601 is provided with a cooling groove for embedding the serpentine cooling pipe 7; the cooling plate bottom plate 603 is attached to the cooling plate shell 601; an O-ring elastic metal sealing ring 602 is provided between the contact surface of the cooling plate shell 601 and the cooling plate bottom plate 603, and is fastened by sealing bolts 605; the cooling plate shell 601 is also fixedly installed on the steel frame 2 by fixing bolts 604.

[0100] In this embodiment, solid-liquid phase change materials (SLCs) are functional materials that undergo reversible phase transitions from solid to liquid (endothermic phase change) or from liquid to solid (exothermic phase change) within a specific temperature range by absorbing or releasing heat, while maintaining a relatively constant temperature during the phase transition. From the perspective of material practicality and process adaptability, SLCs have significant advantages: firstly, they are abundant in sources and simple to manufacture, facilitating large-scale production and cost control; secondly, addressing the issue of low thermal conductivity in some SLCs, the thermal conductivity can be significantly improved by adding high thermal conductivity fillers to the material system. Furthermore, SLCs possess fluidity in their liquid state and can be filled into the honeycomb-shaped SLC containment plate 606 used in this embodiment through methods such as pouring or impregnation. Its porous structure provides a stable containment space for the liquid SLC and also provides constraint through the cavity walls. To prevent material leakage, a customized energy storage and heat dissipation unit adapted to the system structure is ultimately formed. More importantly, this type of material also possesses thermal conductivity responsive adjustment characteristics, meaning that the thermal conductivity can switch between high and low states depending on its phase change. In this embodiment, this characteristic is mainly achieved by doping with high thermal conductivity fillers: when the material is in a liquid state, the high thermal conductivity fillers are randomly dispersed; when the material undergoes a phase change and solidifies to form needle-like crystals, the internal high thermal conductivity fillers align along the crystal boundaries, spontaneously constructing continuous and dense heat conduction channels, thereby significantly improving the material's thermal conductivity in the low-temperature solid-state stage and further optimizing the system's heat transfer efficiency under different operating conditions. That is, utilizing the thermal switching characteristics of solid-liquid phase change materials, during the heating and holding stages of the vacuum sintering furnace, the material's low thermal conductivity blocks heat leakage, achieving a heat insulation function similar to an insulation layer; after entering the rapid cooling stage, the material's high thermal conductivity accelerates heat transfer, thereby achieving rapid cooling of the vacuum sintering furnace.

[0101] Specifically, for the second type of rapid circulating cooling device based on solid-liquid phase change materials, the cooling plate shell 601 completes the pre-setting of the cooling tank and assembly structure during the processing stage, reserving mounting holes for water-cooled electrodes, mounting holes for connection with the steel frame 2, and coke discharge ports for coke discharge. The specific structure of the honeycomb phase change material receiving plate 606 is as follows: Figure 7 As shown, stainless steel is used to quantitatively fill each independent cavity of the honeycomb phase change material receiving plate 606 with solid-liquid phase change material, and a certain amount of space needs to be reserved during the filling operation. The volume compensation space is designed to accommodate the volume expansion of the material during the phase change process, preventing system structural deformation or material cracking due to volume expansion and contraction. After filling, the honeycomb structure phase change material receiving plate 606 is installed in the preset mounting position of the cooling plate shell 601, and the expanded graphite pressure plate 607 is aligned and assembled with the opening section of the honeycomb phase change material receiving plate 606. The expanded graphite pressure plate 607 is made of high-density graphite material and has two main functions: first, as an elastic buffer component, it can absorb the volume expansion of the solid-liquid phase change material due to phase change through its own slight deformation; second, as a sealing barrier, it prevents the liquid phase change material from leaking from the opening end of the receiving plate. To ensure the long-term stable use of the solid-liquid phase change material, a sealing design using a metal shell and bolted clamping is adopted. An O-ring elastic metal sealing ring 602 is installed between the mating surfaces of the 603 cooling plate base plate and the 601 cooling plate shell. By applying uniform circumferential clamping force through pre-drilled mounting holes in both the cooling plate base plate and the cooling plate shell, the sealing effect of the O-ring elastic metal sealing ring 602 is enhanced, while simultaneously ensuring a tight fit between the expanded graphite plate 607 and the honeycomb-shaped receiving plate 606. This prevents leakage of the liquid phase change material. After sealing, the mounting surfaces of the 603 cooling plate base plate and the 601 cooling plate shell remain flush, ensuring a neat system appearance and providing a flat assembly benchmark for subsequent overall installation to the pre-set position on the steel frame 2, avoiding assembly gaps or structural stress caused by uneven mounting surfaces.

[0102] In this embodiment, as Figure 8 As shown, the rapid circulating cooling device 6 adopts a modular and detachable design, with its functional units connected through standardized methods and no permanent fixed structure. The specific installation method is as follows: using the matching steel frame 2 as the installation reference, standardized threaded mounting holes are pre-machined on the steel frame 2 as fixed connection points. At the same time, mounting holes matching the threaded holes of the steel frame are pre-reserved at the corresponding positions on the outer shell of the 601 cooling plate. During installation, fasteners (such as 604 bolts, screws, etc.) are passed through the reserved mounting holes on the outer shell of the 601 cooling plate and precisely aligned and tightened with the reserved threaded holes on the steel frame, thus completing the stable assembly of the rapid circulating cooling system and the steel frame.

[0103] like Figure 9As shown, the serpentine cooling pipe 7 is composed of several groups of partitioned serpentine cooling pipes arranged along the axial direction of the furnace body; each group of partitioned serpentine cooling pipes includes independently controllable: a first partitioned serpentine cooling pipe 701 and a second partitioned serpentine cooling pipe 702.

[0104] For any of the first zone serpentine cooling pipes 701 and the second zone serpentine cooling pipes 702, the inlet of the serpentine cooling pipe is connected to a liquid inlet pipe 8 via a KF flange; the outlet of the serpentine cooling pipe is connected to a liquid return pipe 9 via a KF flange; each serpentine cooling pipe, together with the liquid inlet pipe 8 and the liquid return pipe 9 connected to it, constitutes an independent cooling medium transport path.

[0105] It should be noted that the shapes of the first partition serpentine cooling pipe 701 and the second partition serpentine cooling pipe 702 can also be achieved using other coil forms well known to those skilled in the art.

[0106] Between the steel frame 2 and the cooling plate base plate 603, a number of platinum resistance temperature sensors are provided along the axial direction of the vacuum furnace; the platinum resistance temperature sensors are used to acquire the temperature of the steel frame wall; wherein the temperature of the steel frame wall includes: the real-time temperature value of each monitoring point on the outer wall of the steel frame, the temperature gradient along the axial direction of the vacuum furnace, and the temperature distribution data of the steel frame wall.

[0107] In this embodiment, several platinum resistance temperature sensors are arranged along the axial direction of the vacuum furnace to achieve a distributed arrangement and uniform installation on the outer surface of the steel frame, that is, between the steel frame 2 and the cooling plate bottom plate 603, in order to collect data on the temperature of the steel frame wall. Specifically, this includes: real-time temperature values ​​of each monitoring point on the outer wall of the steel frame, temperature gradient data (i.e., collecting the temperature gradient along the axial direction), and temperature distribution data (i.e., integrating the data of all monitoring points to obtain the overall temperature distribution of the steel frame wall).

[0108] The intelligent rapid circulation cooling system for a large vacuum sintering furnace further includes: a waste heat recovery subsystem; the inlet of the waste heat recovery subsystem is connected to the outlet of the return liquid pipe 9, for receiving the cooling medium flowing out through the return liquid pipe 9; the waste heat recovery subsystem is communicatively connected to the central controller, for dynamically distributing the received cooling medium with waste heat.

[0109] In this embodiment, the waste heat recovery subsystem has the following waste heat distribution paths: 1) transporting the cooling medium containing waste heat to the target vacuum sintering furnace that is in the heating stage and has a matching required temperature; 2) transporting the cooling medium containing waste heat to the high-temperature heat storage tank; 3) transporting the cooling medium containing waste heat to the low-temperature heat storage tank, the equipment foundation insulation device, and the heat dissipation pipes. The selection of the dynamic waste heat distribution path is based on the waste heat temperature of the cooling medium, the waste heat temperature classification, the real-time heat demand and status of the target vacuum sintering furnace and the heat storage tank, thereby ensuring the safe cooling of the working sintering furnace while achieving accurate and effective waste heat recovery.

[0110] like Figure 10 As shown, the central controller includes:

[0111] The parameter initialization module is used to obtain the workpiece parameters of the sintered workpiece and match the target cooling rate curve of the sintered workpiece from the cooling rate curve database based on the workpiece parameters.

[0112] The cooling strategy matching module is used to initialize and start the intelligent rapid circulation cooling system of the large vacuum sintering furnace based on the target cooling rate curve.

[0113] The real-time online monitoring module is used to monitor the operating status parameters of the intelligent rapid circulation cooling system of the large vacuum sintering furnace in real time.

[0114] A multi-level intelligent control module is used to dynamically adjust the flow rate of the cooling medium in the cooling process according to the target cooling rate curve and the operating status parameters, using a preset multi-level control strategy.

[0115] The waste heat recovery control module is used to monitor the temperature of the cooling medium flowing out through the return pipe in real time during the cooling process and use it as the waste heat temperature. Based on the waste heat temperature and the preset priority strategy, it dynamically decides the waste heat distribution path.

[0116] An abnormality protection module is used to trigger the abnormality protection when an abnormality is detected during the cooling process; and to terminate the cooling process when the cooling process reaches a preset termination condition or when the abnormality mechanism triggers a shutdown.

[0117] The post-cooling strategy optimization module is used to record the actual cooling rate curve of this cooling process after the cooling process is completed. By performing deviation analysis on the actual cooling rate curve and the target cooling rate curve, the cooling rate curve database and multi-level control strategy are updated.

[0118] The working process of the intelligent rapid circulation cooling system for a large vacuum sintering furnace is described below: Figure 1As shown, driven by a preset cooling rate curve, the flow rate of coolant flowing from the cooling medium supply device into the inlet pipe 8 located at the lower end of the large vacuum sintering furnace is dynamically adjusted by an electric regulating valve 12. The coolant flows into the serpentine cooling pipe 7 inside the furnace through the inlet pipe 8. The serpentine cooling pipe 7 is tightly embedded in the cooling groove reserved on the cooling plate shell 601. The cooling plate shell 601 encapsulates a phase change material with a specific working temperature range. The key characteristic of the phase change material is that, within its working phase change temperature range, it can absorb or release a large amount of latent heat through a reversible phase transformation process (such as solid-solid crystal transformation or melting). When the sintering furnace enters the rapid cooling stage, the heat generated in the high-temperature zone inside the furnace is transferred to the phase change material through both thermal radiation and heat transfer. After being heated to its phase change point, the phase change material undergoes a phase change and absorbs a large amount of heat, thereby effectively buffering temperature fluctuations and achieving uniform cooling. At the same time, the coolant flowing through the serpentine cooling pipe 7 continuously carries away the heat absorbed and stored by the phase change material from the furnace. This continuous supply of cold source ensures that the phase change material can continuously absorb heat in a cycle.

[0119] Given that large vacuum sintering furnaces (such as the 13.6m vacuum sintering furnace described in this embodiment) have temperature differences along their axial direction, in order to improve cooling efficiency and thermal management accuracy, multiple sets (preferably 4 sets in this embodiment) are arranged along the axial direction of the furnace body. Figure 8 The first and second serpentine cooling pipes (shown) are independently controllable, with the arrangement density of each group of cooling pipes differentiated according to the temperature distribution of the corresponding area: in the high-temperature zone (center of the furnace body), the cooling pipe arrangement density is higher to enhance heat exchange capacity; in the low-temperature zone (both ends of the furnace body), the arrangement density is appropriately reduced to avoid over-cooling and energy waste. Furthermore, the coolant after heat exchange is completed is discharged through the return pipe 9 located at the upper end of the furnace body and flows into the waste heat recovery subsystem, thereby automatically matching the optimal recovery direction based on the waste heat value.

[0120] Example 2:

[0121] This embodiment presents an intelligent rapid circulating cooling method for a large vacuum sintering furnace, employing the approach proposed in Embodiment 1, such as... Figure 1 The above describes an intelligent rapid circulation cooling system for a large vacuum sintering furnace. This method is built around the entire cycle of the workpiece cooling process, such as... Figure 11 As shown, the method includes the following steps:

[0122] Obtain the workpiece parameters of the sintered workpiece, and match the target cooling rate curve of the sintered workpiece from the cooling rate curve database based on the workpiece parameters.

[0123] In this embodiment, the core idea of ​​the cooling rate curve is to minimize the cooling process completion time by optimizing the nonlinear cooling path, while ensuring that the internal thermal stress of the workpiece remains below the material's yield strength and avoiding thermal cracking and deformation. This achieves a synergistic improvement in cooling efficiency and process stability while maintaining the reliability of the microstructure and properties. Intelligent matching of the cooling rate curve from the cooling rate curve database based on the sintered workpiece parameters provides a theoretical basis for the control and optimization of subsequent cooling processes.

[0124] The specific content of obtaining the workpiece parameters of the sintered workpiece and matching the target cooling rate curve of the sintered workpiece from the cooling rate curve database based on the workpiece parameters is as follows:

[0125] For any sintered workpiece, obtain the workpiece parameters; wherein the workpiece parameters include: workpiece shape parameters, workpiece size parameters, tooling method parameters, and material property parameters.

[0126] In this embodiment, the workpiece shape parameters include: flat plates, solid cylinders, hollow cylinders, and irregularly shaped parts. Workpiece dimension parameters include: flat plates: thickness, length, width; solid cylinders: diameter, length; hollow cylinders: inner diameter, outer diameter, length; irregularly shaped parts: equivalent thickness, maximum outline dimension, thickness of critical parts. Tooling parameters include: number of horizontal columns, horizontal spacing, number of stacked layers, and interlayer spacing. Material property parameters include: thermal conductivity and coefficient of thermal expansion.

[0127] The workpiece parameters are standardized to obtain workpiece parameter codes.

[0128] Using the workpiece parameter code as the search criteria, a search is performed in a preset cooling rate curve database.

[0129] In this embodiment, as Figure 12 As shown, the user inputs the workpiece parameters for sintering. A set of input workpiece parameter values ​​is treated as a workpiece parameter combination. This combination is standardized, and non-numerical parameters are converted into database-recognizable data codes. These codes are then used as search criteria to find the corresponding cooling rate curve in the database. For high-frequency workpiece parameter combinations, the cooling rate curve is directly extracted through retrieval. For medium- and low-frequency workpiece parameter combinations, a random forest regression model is used to predict and generate the corresponding cooling rate curve. Furthermore, for some medium- and low-frequency parameter combinations, the predicted curve is further optimized by considering the combination difference patterns.

[0130] If a cooling rate curve corresponding to the workpiece parameter code exists in the cooling rate curve database, then that cooling rate curve is directly called as the target cooling rate curve for the sintered workpiece.

[0131] If the cooling rate curve database does not contain a cooling rate curve corresponding to the workpiece parameter code, the workpiece parameter code is input into a pre-trained random forest regression model for prediction to generate the target cooling rate curve for the sintered workpiece.

[0132] The method for constructing the pre-trained random forest regression model is as follows:

[0133] Obtain several sets of process parameter combinations for sintered workpieces; wherein the process parameter combination consists of the values ​​of a set of process parameters.

[0134] A three-dimensional model of the intelligent rapid circulation cooling system of the large vacuum sintering furnace was constructed, and based on the constructed three-dimensional model, finite element simulation was performed on each combination of process parameters to record the cooling rate of the steel frame wall and the maximum thermal stress of the sintered workpiece in different temperature ranges.

[0135] A set of process parameters, along with the cooling rate of the steel frame wall and the maximum thermal stress of the sintered workpiece in different temperature ranges corresponding to that set of process parameters, are used as training samples to construct a training sample set.

[0136] Using process parameter combinations and temperature ranges as input features, and the cooling rate of the steel frame wall and the maximum thermal stress of the sintered workpiece as target outputs, a random forest regression model is trained using the training sample set to obtain a pre-trained random forest regression model.

[0137] In this embodiment, as Figure 12 As shown, finite element simulation analysis can also reveal the influence of workpiece parameters on cooling efficiency. These patterns can be used to verify the rationality of the model and serve as prior knowledge to guide subsequent model optimization iterations. It should be noted that the cooling rate curve database has self-learning iteration capabilities; that is, it can perform real-time deviation analysis between actual and theoretical curves, supplementing the database with new data generated during the real-time cooling process, rather than relying on historical data. By re-storing the corrected data in the database, both historical data are optimized, and new training samples are provided for the prediction model, forming a closed loop of "historical data, prediction model, real-time data, corrected data, and updated historical data."

[0138] Based on the target cooling rate curve, the intelligent rapid circulation cooling system of the large vacuum sintering furnace is initialized and started.

[0139] The specific steps for initializing and starting the intelligent rapid circulation cooling system of the large vacuum sintering furnace based on the target cooling rate curve are as follows:

[0140] Based on the workpiece parameters and target cooling rate curve of the sintered workpiece, the initial process parameters of the intelligent rapid circulation cooling system of the large vacuum sintering furnace are determined.

[0141] The initial process parameters include: cooling medium parameters, piping and equipment parameters, furnace initial state parameters, process target parameters, and safety threshold parameters.

[0142] The cooling medium parameters include: the initial temperature of the cooling medium and the allowable flow rate range of the medium.

[0143] The pipeline and equipment parameters include: the selection of the waste heat recovery path and the rated power of the cooling medium supply equipment.

[0144] The initial state parameters of the furnace body include: the initial temperature inside the furnace and the initial axial temperature distribution of the furnace body.

[0145] The process target parameters include: the target cooling rate range and the target cooling endpoint temperature for each temperature range.

[0146] The safety threshold parameters include: temperature uniformity threshold, over-temperature alarm threshold, coolant leakage monitoring threshold, and maximum thermal stress threshold.

[0147] The intelligent rapid circulation cooling system of the large vacuum sintering furnace is initialized according to the initial process parameters.

[0148] In this embodiment, the initialization process of the intelligent rapid circulation cooling system for the large vacuum sintering furnace is based on multi-dimensional parameters and the target cooling rate curve. It achieves automated configuration through rule matching and hardware linkage to ensure that the initial cooling conditions precisely match the workpiece requirements. For example, regarding the cooling medium supply equipment: a pump with appropriate power is matched based on the workpiece parameters, and the initial flow rate and the opening range of the electric regulating valve 12 are preset according to the cooling medium parameters and the pipeline and equipment parameters. Regarding the waste heat recovery pipelines and equipment, the waste heat temperature is pre-determined and graded based on the initial furnace temperature.

[0149] The intelligent rapid circulation cooling system of the large vacuum sintering furnace is started after initialization.

[0150] During the cooling process, the operating status parameters of the system are monitored in real time, and the cooling medium flow rate is dynamically adjusted according to the target cooling rate curve and the operating status parameters using a preset multi-level control strategy.

[0151] In this embodiment, as Figure 13As shown, the core idea of ​​dynamically adjusting the cooling medium flow rate during the cooling process is to achieve precise and intelligent control of the cooling process by using the key process parameters of the vacuum sintering furnace as the basis for regulation and control, and through a closed-loop linkage of multi-level data processing and decision execution. Driven by real-time online detection data, a multi-level intelligent control module is constructed. Based on thermal stress assessment and the target cooling curve, intelligent rate control is performed to dynamically adjust the coolant flow rate and precisely control the cooling rate. To address the problem of uneven temperature distribution along the furnace axial direction during cooling, a zoned coordinated control strategy is introduced to achieve differentiated regulation of cooling parameters according to regional temperature variations, balancing the temperature uniformity of each region. Dynamic waste heat distribution identifies the temporal sequence of temperatures during cooling, intelligently switches recovery pipes, and intelligently selects the optimal recovery path to achieve intelligent waste heat recovery.

[0152] The specific details of dynamically adjusting the cooling medium flow rate during the cooling process using a preset multi-level control strategy, with the target cooling rate curve as the adjustment target and the operating status parameters as the basis, are as follows:

[0153] The operating status parameters of the intelligent rapid circulation cooling system of the large vacuum sintering furnace are monitored in real time; wherein the operating status parameters include: steel frame wall temperature, cooling medium temperature and cooling medium flow rate.

[0154] In this embodiment, the temperature of the steel frame wall is collected in real time by several platinum resistance temperature sensors arranged along the axial direction of the vacuum furnace, the temperature of the cooling medium is collected in real time by a type K armored thermocouple temperature sensor 11, and the flow rate of the cooling medium is collected in real time by a vortex flow meter 10.

[0155] Based on real-time acquired operating status parameters, real-time thermal stress is calculated. If the real-time thermal stress exceeds the maximum thermal stress threshold, an abnormal protection mechanism is triggered. If the real-time thermal stress does not exceed the maximum thermal stress threshold, each zone of the serpentine cooling pipe is considered a temperature-controlled zone, and the temperature difference between any two adjacent temperature-controlled zones is calculated. .

[0156] In this embodiment, based on real-time acquired operating status parameters, real-time thermal stress is calculated and compared with the maximum thermal stress threshold to conduct a thermal stress risk assessment. Simultaneously, it provides real-time, dynamic data support for intelligent control and anomaly early warning of the cooling process, achieving transparent monitoring throughout the entire cooling cycle. Specifically, the thermal stress assessment results determine the activation priority of the control strategy: once the real-time thermal stress exceeds the safety threshold, the anomaly protection mechanism will be activated first, rather than continuing to execute zoned coordinated control or intelligent rate control. At this time, the large vacuum sintering furnace will quickly switch to safety mode and stop the operation of the intelligent rapid circulation cooling system, switching to natural heat dissipation, while simultaneously notifying the operator to intervene.

[0157] In this embodiment, the temperature of each temperature-controlled zone is obtained based on the real-time collected temperature of the steel frame wall, and then the temperature difference between any two adjacent temperature-controlled zones is calculated. .

[0158] When there is a temperature difference between any two adjacent temperature control zones When the flow rate is high, zone coordination control is executed to regulate the flow rate of the cooling medium during the cooling process; conversely, intelligent rate control is executed to regulate the flow rate of the cooling medium during the cooling process.

[0159] The specific content of the partition coordination control is as follows:

[0160] For any temperature control zone, calculate the target flow rate for that zone, and adjust the cooling medium flow rate to the target flow rate by adjusting the opening of the electric regulating valve.

[0161] The target flow rate is calculated as follows:

[0162]

[0163] in, For target traffic; For the current moment The flow rate of the cooling medium; This refers to the flow rate regulation coefficient. In this embodiment, based on the temperature of all temperature-controlled zones, all temperature-controlled zones are divided into high-temperature zones and low-temperature zones. There are two criteria for this division: First, temperature-controlled zones with a current temperature higher than a preset temperature value are classified as high-temperature zones, and those with a current temperature lower than a preset temperature value are classified as low-temperature zones. Second, all temperature-controlled zones are sorted according to their current temperature values, with zones having higher temperatures assigned to high-temperature zones and those having lower temperatures assigned to low-temperature zones. For temperature-controlled zones belonging to the high-temperature zone, when the temperature difference between this zone and its adjacent zones... At that time, the flow regulation coefficient When the temperature difference between this temperature zone and the adjacent temperature zone At that time, the flow regulation coefficient For temperature-controlled zones belonging to the low-temperature zone group, when the temperature difference between this temperature zone and the adjacent temperature zone... At that time, the flow regulation coefficient When the temperature difference between this temperature zone and the adjacent temperature zone At that time, the flow regulation coefficient .

[0164] Each preset control cycle Real-time calculation of the temperature difference between every two adjacent temperature control zones. If the temperature difference of all adjacent temperature control zones If so, then the partition coordination control ends and intelligent rate control is executed; if continuously... Even after one control cycle, there is still a temperature difference between any two adjacent temperature control zones. If the adjustment coefficient is increased according to the preset ratio, the real-time thermal stress is recalculated and compared with the maximum thermal stress threshold.

[0165] In this embodiment, the temperature difference between zones is calculated every 5 seconds. If temperature uniformity is restored, the current round of regulation is terminated; if it persists after three adjustments... The regulation was deemed insufficient, and the adjustment coefficient was increased to [a higher level]. It also triggers a secondary assessment of thermal stress; that is, if the real-time thermal stress exceeds the maximum thermal stress threshold, an anomaly protection mechanism is triggered.

[0166] In this embodiment, when the temperature difference between any two adjacent temperature control zones exceeds... At this time, zone coordination control is triggered. The temperature control zones are divided into high-temperature and low-temperature groups based on their temperature levels. For all temperature control zones in the high-temperature group, a command is sent to increase the coolant flow rate to enhance the cooling effect and quickly lower the zone temperature. For all temperature control zones in the low-temperature group, a command is sent to decrease the coolant flow rate to slow down the cooling rate and prevent overcooling. During the control process, the temperature distribution of the entire furnace is continuously monitored until the temperature gradient of all temperature control zones returns to normal. Within this range, a complete dynamic closed-loop regulation is achieved.

[0167] The specific details of the intelligent rate control are as follows:

[0168] The real-time cooling rate is calculated based on the steel frame wall temperature, and then the cooling rate deviation is calculated based on the target cooling rate curve.

[0169] The real-time cooling rate is:

[0170]

[0171] in, For the current moment Real-time cooling rate, in units of ; The temperature of the steel frame wall surface 10 seconds ago; For the current moment The steel frame wall temperature; the steel frame wall temperature is derived from the time-series temperature data of the steel frame wall collected by the PT100 platinum resistance sensor after filtering and noise reduction preprocessing.

[0172] The cooling rate deviation is:

[0173]

[0174] in, For the current moment The deviation in cooling rate; For the current moment The target cooling rate.

[0175] If the difference between the cooling rate deviation and the set deviation does not exceed the preset fine-tuning threshold, the PID control algorithm is used to calculate and adjust the cooling medium flow rate; otherwise, the cooling medium flow rate is adjusted according to the preset adjustment rules.

[0176] In this embodiment, as Figure 13 As shown, when At that time, the PID control output is calculated, which is the adjustment amount of the cooling medium flow rate, where, To set the deviation; The preset fine-tuning threshold is, in this embodiment, approximately equal to the threshold set when performing PID fine-tuning. The criteria for judgment.

[0177]

[0178] in, Indicates the adjustment amount of the cooling medium flow rate; This is a proportional coefficient, set according to the degree of influence of the deviation on flow regulation. In high-temperature zones, due to rapid temperature changes and relatively low thermal inertia, its... The value can be appropriately increased to quickly address the deviation, while the values ​​in the medium and low temperature ranges can be adjusted accordingly. The value should be gradually decreased to avoid over-adjustment. The integral coefficient is used to determine the rapid and stable cooling rate in the high-temperature region, based on the requirement to eliminate static deviation. The value can be appropriately reduced to prevent excessive accumulation of integrals leading to overshoot; in the medium and low temperature regions... The value can be appropriately increased to more thoroughly eliminate long-standing minor deviations; These are differential coefficients used to predict the trend of deviation changes. In high-temperature regions, due to their large rate of temperature change... Increasing the value can predict and suppress drastic fluctuations in the cooling rate in advance; in the medium and low temperature zones... The value decreases, reducing the overreaction to small changes in temperature.

[0179] when If the cooling rate deviation exceeds the set deviation, the cooling medium flow rate is adjusted according to the preset first adjustment rule, such as... Figure 13 As shown; when the cooling rate deviation is less than the set deviation, the flow rate of the cooling medium is adjusted according to the preset second adjustment rule.

[0180] After adjusting the flow rate of the cooling medium, the real-time thermal stress is recalculated. If the recalculated real-time thermal stress meets the safety condition judgment conditions, intelligent rate control continues until the cooling process ends; otherwise, the abnormal mechanism protection is triggered.

[0181] In this embodiment, with As a prerequisite for intelligent rate control, among which For real-time thermal stress; The yield strength of the material; when In such cases, regulation should be suspended and abnormal protection should be activated.

[0182] To address the issue of energy reuse during the cooling process, a waste heat recovery system is set up to identify the waste heat value in different temperature ranges through priority ranking. Based on the ranking results, specific waste heat recovery methods are planned, and the direction of waste heat utilization is clarified (such as: preheating other target vacuum sintering furnaces, heat storage tanks, and heat dissipation pipes, etc.), so as to achieve closed-loop optimized utilization of energy.

[0183] During the cooling process, the temperature of the cooling medium flowing out through the return pipe 9 is monitored in real time and used as the waste heat temperature. Based on the waste heat temperature and the preset priority strategy, the waste heat distribution path is dynamically determined.

[0184] In this embodiment, as Figure 14 As shown, according to the preset priority strategy, the target vacuum sintering furnace in the heating stage with matching required temperature is designated as the high-priority waste heat distribution path; the high-temperature heat storage tank is designated as the medium-priority waste heat distribution path; and the low-temperature heat storage tank, equipment foundation insulation, and heat dissipation pipes are designated as the low-priority waste heat distribution paths. The waste heat recovery subsystem integrates multiple requirements, including the heating demand of the target vacuum sintering furnace, high / low-temperature heat storage functions, and redundant heat dissipation control of the heat dissipation pipes, to dynamically control waste heat distribution while ensuring the cooling safety of the working sintering furnace. Specifically, waste heat is prioritized according to temperature, from high to low, to meet high-value, highly matched heat demands, achieving efficient utilization of waste heat and reducing overall system energy consumption. High priority refers to waste heat temperatures located at... This can directly meet high-value heating needs. Medium priority: Waste heat temperature is located at... While it cannot meet high-value heating needs, it can be stored for secondary use. Low priority: Waste heat temperature less than... Its utilization value is limited.

[0185] When an abnormal situation is detected during the cooling process, the abnormality protection mechanism is triggered; when the cooling process reaches the preset termination condition or the shutdown is triggered by the abnormality mechanism, the cooling process is terminated.

[0186] In this embodiment, abnormal situations during the cooling process include: overheating, coolant leakage, and sensor failure. Overheating can be detected by k-type armored thermocouple temperature sensors 12 arranged on the inlet pipe 8 and return pipe 9 in each temperature control zone, as well as platinum resistance temperature sensors arranged in each temperature control zone. When the real-time collected temperature exceeds a temperature threshold, an overheating situation is considered to exist. Coolant leakage can be detected by vortex flow meters 10 arranged on the inlet pipe 8 and return pipe 9 in each zone, which collect the inflow and outflow flow rates of coolant in real time. When a coolant leak occurs, the outlet flow rate will be significantly less than the inlet flow rate. If the flow difference exceeds a set threshold, the system will determine it as a suspected leak. Simultaneously, the temperature changes of the coolant can also be obtained through the deployed k-type armored thermocouple temperature sensors 11. When a leak occurs, the coolant flow rate in the corresponding area will decrease, the heat exchange efficiency will decrease accordingly, and the temperature in that area will fluctuate abnormally. The system uses these temperature data abrupt changes to help determine the leak problem. When the above-mentioned abnormal situations are detected, the system automatically executes the abnormality protection mechanism. On the one hand, it quickly switches to the safety mode, stops the cooling system and switches to natural heat dissipation mode; on the other hand, it notifies the operator to intervene and prevent the risk of the abnormal situation from spreading, thereby ensuring equipment safety and stable workpiece quality.

[0187] In this embodiment, the preset termination conditions include: the workpiece temperature drops to the furnace opening standard, the cooling cycle ends, etc. When the cooling process reaches the preset termination conditions or the shutdown is triggered by the abnormal mechanism, the system will perform the termination cooling operation and orderly complete the process of stopping the supply of coolant.

[0188] After the cooling process is completed, the actual cooling rate curve of this cooling process is recorded. By performing deviation analysis between the actual cooling rate curve and the target cooling rate curve, the cooling rate curve database and multi-level control strategy are updated.

[0189] In this embodiment, after the cooling process is completed, the system records the actual cooling rate curve during this cooling process, providing data support for comparing the deviation of the prediction model. Deviation analysis is performed on the actual cooling rate curve and the target cooling rate curve, including: temporal deviation and spatial deviation; wherein the temporal deviation is: initial deviation and deviation development trajectory. The spatial deviation is: high-temperature zone deviation and low-temperature zone deviation. Based on the deviation analysis results, the system automatically adjusts safety parameters and updates the optimal control strategy, and continuously iterates the cooling algorithm to improve the accuracy and stability of subsequent cooling processes.

[0190] The method for updating the cooling rate curve database and multi-level control strategy by performing deviation analysis on the actual cooling rate curve and the target cooling rate curve is as follows:

[0191] Outlier removal and time alignment are performed on the steel frame wall temperature and cooling medium flow rate collected in time series to obtain time-synchronized steel frame wall temperature and cooling medium flow rate, so as to avoid interference and bias judgment.

[0192] Based on the axial position of the furnace body, the furnace body is divided into a high-temperature zone, a medium-temperature zone, and a low-temperature zone.

[0193] In this embodiment, due to the natural characteristics of the furnace body, the temperature field along the axial direction of the furnace body exhibits a distribution pattern of high temperature in the middle and low temperature at both ends, meaning that the temperature in the area far from the furnace door is higher than that in the area near the furnace door. Therefore, based on the axial position of the furnace body, the furnace body is physically divided into regions: the center of the furnace body is considered the high-temperature zone, the two ends of the furnace body are considered the low-temperature zones, and the transitional area between the high-temperature and low-temperature zones is considered the medium-temperature zone, thus providing a structured data foundation for zoning deviation analysis.

[0194] Based on the time-synchronized steel frame wall temperature and cooling medium flow rate, the initial point of deviation between the actual cooling rate curve and the target cooling rate curve is determined, and the deviation start time, initial temperature, and cooling rate difference corresponding to the initial point of deviation are obtained.

[0195] Starting from the initial deviation point, the real-time deviation values ​​of several deviation points are calculated at fixed time intervals to form a time-series deviation sequence.

[0196] By fitting the time-series deviation sequence, the deviation type of the actual cooling rate curve is determined to be either a gradual deviation or an abrupt deviation, and a cooling process calibration operation is performed based on the deviation type of the actual cooling rate curve.

[0197] In this embodiment, the trend of deviation over time is analyzed through linear or nonlinear fitting to distinguish between gradual deviation (caused by equipment degradation) and abrupt deviation (caused by sensor failure or sudden changes in operating conditions). The characteristics of gradual deviation are: the actual cooling rate curve deviates slowly and over a long period from the target cooling rate curve, without sudden fluctuations. The calibration operations corresponding to gradual deviation are: 1) Perform equipment degradation parameter calibration to correct the coefficients related to the performance degradation of the cooling system and compensate for the decrease in cooling capacity caused by long-term operation. 2) Conduct model core parameter calibration to optimize the prediction model based on the long-term variation law of the deviation, eliminating the inherent deviation between the theoretical curve and the actual operating conditions. The characteristics of abrupt deviation are: the actual cooling rate curve suddenly jumps at a certain point in time, with a large and irregular deviation. The calibration operations corresponding to abrupt deviation are: 1) Prioritize triggering the fault diagnosis mechanism to check whether hardware such as sensors and actuators are abnormal; for example, sensor failure can lead to distorted temperature data. 2) If a hardware failure is confirmed, directly remove the abnormal data, supplement it with historical normal data or redundant sensor data, and then recalculate the cooling curve deviation. 3) If there is no hardware fault, adjust the temperature threshold and cooling rate threshold to adapt to sudden fluctuations in operating conditions.

[0198] In this embodiment, the reasons for distinguishing the types of deviations are as follows: (1) Avoiding miscalibration: If the deviations caused by sensor failures are not distinguished, the sudden deviations will be treated as gradual deviations of equipment degradation, which will lead to incorrect adjustment of model parameters, causing the subsequent control strategy to deviate from the target and exacerbating the instability of the cooling process. (2) Ensuring the reliability of the self-learning mechanism: The self-learning closed loop of the system relies on the logic of "data recording - deviation analysis - parameter calibration - strategy evolution". Only by accurately distinguishing the types of deviations can effective correction parameters be generated to ensure that the optimized cooling curve and control strategy conform to the actual working conditions.

[0199] Based on the time-series deviation sequence, the average deviation of the high-temperature zone, the average deviation of the medium-temperature zone, and the average deviation of the low-temperature zone are calculated respectively, and a deviation heatmap is generated based on the calculation results.

[0200] The method for calculating the average deviation of the partition is as follows:

[0201]

[0202] in, The average deviation of any zone within the high-temperature, medium-temperature, and low-temperature zones; This represents the number of data points in the partition. For the first in this partition The absolute value of each real-time deviation.

[0203] In this embodiment, by generating a deviation heatmap, the average deviation of each partition is visualized, and key calibration areas with large deviations are intuitively identified.

[0204] By comparing the overall trends of the actual cooling rate curve and the target cooling rate curve, and combining the deviation type and deviation heatmap of the actual cooling rate curve, the actual cooling rate curve is corrected, and the corrected actual cooling rate curve is used to update the cooling rate curve database and multi-level control strategy.

[0205] In this embodiment, by comparing the overall trends of the actual curve and the target curve, two types of core trend deviations are identified: if the actual cooling rate curve remains below the target curve from the initial point of deviation (indicating cooling efficiency degradation or overly optimistic model predictions), the persistence of the actual cooling rate curve is lower than the deviation; if the actual cooling rate curve remains above the target curve from the initial point of deviation (indicating cooling efficiency exceeding expectations or overly conservative model predictions), the persistence of the actual cooling rate curve is higher than the deviation. Based on the deviation analysis results, the actual cooling rate curve is corrected by saving the corrected actual cooling rate curve to the cooling rate curve database to update the database. Simultaneously, the multi-level control strategy is updated based on the corrected actual cooling rate curve. The updated objects include: various actuators, such as electric regulating valves and cooling medium supply equipment; and various state parameters, such as cooling medium flow rate, furnace zone temperature, and various safety threshold parameters.

[0206] In this embodiment, as Figure 15 As shown, by recording the cooling curve under actual operating conditions in real time and performing deviation quantification calculation and comparative analysis between the curve and the theoretical cooling curve output by the prediction model, a deviation feedback closed loop is constructed. Based on this closed-loop feedback, the system can automatically complete two key optimizations: first, dynamically calibrating the preset safety control parameters to ensure the adaptability of parameter thresholds to the actual operating state; second, iteratively updating the optimal control strategy library based on deviation patterns and historical optimization data, enabling the control logic to autonomously evolve with the accumulation of operating conditions.

[0207] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope defined by the present invention.

Claims

1. An intelligent rapid circulating cooling system for a large vacuum sintering furnace, characterized in that, The system includes: furnace shell, steel frame, carbon felt, graphite plate, heating element assembly, rapid circulation cooling device, serpentine cooling pipe, vortex flow meter, K-type armored thermocouple temperature sensor, electric regulating valve, furnace door, and central controller. The furnace shell is equipped with a steel frame, and a carbon felt is fixed inside the steel frame; the graphite plate is installed inside the carbon felt; the heating element assembly is installed inside the graphite plate; the rapid circulation cooling device is installed outside the steel frame; the serpentine cooling pipe is embedded on the outer surface of the rapid circulation cooling device; the inlet of the serpentine cooling pipe is connected to a liquid inlet pipe that penetrates the furnace shell; the outlet of the serpentine cooling pipe is connected to a liquid return pipe that penetrates the furnace shell. The vortex flow meter is installed on the inlet pipe to monitor the flow rate of the cooling medium in the inlet pipe in real time; the electric regulating valve is installed on the inlet pipe to regulate the flow rate of the cooling medium in the inlet pipe; both the inlet pipe and the return pipe are equipped with type K armored thermocouple temperature sensors. The furnace door is pressed tightly against the furnace shell to form a sealed vacuum working chamber; The central controller is communicatively connected to the vortex flow meter, the k-type armored thermocouple temperature sensor, and the electric regulating valve.

2. The intelligent rapid circulating cooling system for a large vacuum sintering furnace according to claim 1, characterized in that, The rapid circulation cooling device is internally encapsulated with a phase change material; the phase change material is used to absorb heat inside the steel frame; according to the type of phase change material, the rapid circulation cooling device is divided into two types of structures: a first type of rapid circulation cooling device based on solid-solid phase change material and a second type of rapid circulation cooling device based on solid-liquid phase change material. The first type of rapid circulation cooling device includes: a cooling plate shell, an O-ring elastic metal sealing ring, a cooling plate base plate, fixing bolts, and sealing bolts; The cooling plate outer shell is a shell with an inner cavity, and the inner cavity of the cooling plate outer shell is filled with a solid-solid phase change material; the outer surface of the cooling plate outer shell is provided with a cooling groove for embedding a serpentine cooling tube; the cooling plate bottom plate is attached to the cooling plate outer shell; an O-ring elastic metal sealing ring is provided between the contact surface of the cooling plate outer shell and the cooling plate bottom plate, and the connection is fastened by sealing bolts; the cooling plate outer shell is also fixedly mounted on a steel frame by fixing bolts. The second type of rapid circulation cooling device includes: a cooling plate shell, an O-ring elastic metal sealing ring, a cooling plate base plate, fixing bolts, sealing bolts, a honeycomb phase change material receiving plate, and an expanded graphite pressure plate; Each independent cavity of the honeycomb phase change material receiving plate is filled with a fixed amount of solid-liquid phase change material; the cooling plate shell is a shell with an inner cavity, and the filled honeycomb phase change material receiving plate is installed in the inner cavity of the cooling plate shell; the expanded graphite pressure plate is aligned and assembled with the open end of the honeycomb phase change material receiving plate; the outer surface of the cooling plate shell is provided with a cooling groove for embedding serpentine cooling pipes; the cooling plate bottom plate is attached to the cooling plate shell; an O-ring elastic metal sealing ring is provided between the contact surface of the cooling plate shell and the cooling plate bottom plate, and is fastened by sealing bolts; the cooling plate shell is also fixedly mounted on a steel frame by fixing bolts.

3. The intelligent rapid circulating cooling system for a large vacuum sintering furnace according to claim 1, characterized in that, The serpentine cooling pipe consists of several groups of partitioned serpentine cooling pipes arranged along the axial direction of the furnace body; each group of partitioned serpentine cooling pipes includes two independently controllable partitioned serpentine cooling pipes: a first partitioned serpentine cooling pipe and a second partitioned serpentine cooling pipe. For any one of the first and second zone serpentine cooling pipes, the inlet of the serpentine cooling pipe is connected to a liquid inlet pipe via a KF flange; the outlet of the serpentine cooling pipe is connected to a liquid return pipe via a KF flange; each serpentine cooling pipe, together with the liquid inlet pipe and the liquid return pipe connected to it, constitutes an independent cooling medium transport path.

4. The intelligent rapid circulating cooling system for a large vacuum sintering furnace according to claim 1, characterized in that, Between the steel frame and the cooling plate base, a number of platinum resistance temperature sensors are installed along the axial direction of the vacuum furnace; the platinum resistance temperature sensors are used to acquire the temperature of the steel frame wall; wherein the steel frame wall temperature includes: the real-time temperature value of each monitoring point on the outer wall of the steel frame, the temperature gradient along the axial direction of the vacuum furnace, and the temperature distribution data of the steel frame wall.

5. The intelligent rapid circulating cooling system for a large vacuum sintering furnace according to claim 1, characterized in that, The intelligent rapid circulation cooling system for a large vacuum sintering furnace further includes: a waste heat recovery subsystem; the inlet of the waste heat recovery subsystem is connected to the outlet of the return liquid pipe for receiving the cooling medium flowing out through the return liquid pipe; the waste heat recovery subsystem is communicatively connected to the central controller for dynamically distributing the received cooling medium.

6. The intelligent rapid circulating cooling system for a large vacuum sintering furnace according to claim 1, characterized in that, The central controller includes: The parameter initialization module is used to obtain the workpiece parameters of the sintered workpiece and match the target cooling rate curve of the sintered workpiece from the cooling rate curve database based on the workpiece parameters. The cooling strategy matching module is used to initialize and start the intelligent rapid circulation cooling system of the large vacuum sintering furnace based on the target cooling rate curve. The real-time online detection module is used to monitor the operating status parameters of the intelligent rapid circulation cooling system of the large vacuum sintering furnace in real time. A multi-level intelligent control module is used to dynamically adjust the cooling medium flow rate during the cooling process based on the target cooling rate curve and the operating status parameters, using a preset multi-level control strategy. The waste heat recovery control module is used to monitor the temperature of the cooling medium flowing out through the return liquid pipe in real time during the cooling process and use it as the waste heat temperature. Based on the waste heat temperature and the preset priority strategy, it dynamically decides the waste heat distribution path. An abnormality protection module is used to trigger the abnormality protection when an abnormality is detected during the cooling process; and to terminate the cooling process when the cooling process reaches a preset termination condition or when the abnormality mechanism triggers a shutdown. The post-cooling strategy optimization module is used to record the actual cooling rate curve of this cooling process after the cooling process is completed. By performing deviation analysis on the actual cooling rate curve and the target cooling rate curve, the cooling rate curve database and multi-level control strategy are updated.

7. A method for intelligent rapid circulating cooling of a large vacuum sintering furnace, implemented using the intelligent rapid circulating cooling system for a large vacuum sintering furnace as described in any one of claims 1-6, characterized in that, This method includes the following steps: Obtain the workpiece parameters of the sintered workpiece, and match the target cooling rate curve of the sintered workpiece from the cooling rate curve database based on the workpiece parameters. Based on the target cooling rate curve, initialize and start the intelligent rapid circulation cooling system of the large vacuum sintering furnace; During the cooling process, the operating status parameters of the system are monitored in real time, and the cooling medium flow rate is dynamically adjusted according to the target cooling rate curve and the operating status parameters using a preset multi-level control strategy. During the cooling process, the temperature of the cooling medium flowing out through the return pipe is monitored in real time and used as the waste heat temperature. Based on the waste heat temperature and the preset priority strategy, the waste heat distribution path is dynamically determined. When an abnormal situation is detected during the cooling process, the abnormality protection mechanism is triggered; when the cooling process reaches the preset termination condition or the abnormality protection mechanism triggers a shutdown, the cooling process is terminated. After the cooling process is completed, the actual cooling rate curve of this cooling process is recorded. By performing deviation analysis between the actual cooling rate curve and the target cooling rate curve, the cooling rate curve database and multi-level control strategy are updated.

8. The intelligent rapid circulating cooling method for a large vacuum sintering furnace according to claim 7, characterized in that, The specific content of obtaining the workpiece parameters of the sintered workpiece and matching the target cooling rate curve of the sintered workpiece from the cooling rate curve database based on the workpiece parameters is as follows: For any sintered workpiece, obtain the workpiece parameters; wherein the workpiece parameters include: workpiece shape parameters, workpiece size parameters, tooling method parameters, and material property parameters. The workpiece parameters are standardized to obtain workpiece parameter codes; Using the workpiece parameter code as the search criteria, a search is performed in a preset cooling rate curve database; If a cooling rate curve corresponding to the workpiece parameter code exists in the cooling rate curve database, then the cooling rate curve is directly called as the target cooling rate curve for the sintered workpiece. If the cooling rate curve database does not contain a cooling rate curve corresponding to the workpiece parameter code, the workpiece parameter code is input into a pre-trained random forest regression model for prediction to generate the target cooling rate curve for the sintered workpiece.

9. The intelligent rapid circulating cooling method for a large vacuum sintering furnace according to claim 7, characterized in that, The specific details of dynamically adjusting the cooling medium flow rate during the cooling process using a preset multi-level control strategy, with the target cooling rate curve as the adjustment target and the operating status parameters as the basis, are as follows: The operating status parameters of the intelligent rapid circulation cooling system of the large vacuum sintering furnace are monitored in real time; wherein the operating status parameters include: steel frame wall temperature, cooling medium temperature and cooling medium flow rate; Based on real-time acquired operating status parameters, real-time thermal stress is calculated. If the real-time thermal stress exceeds the maximum thermal stress threshold, an abnormal protection mechanism is triggered. If the real-time thermal stress does not exceed the maximum thermal stress threshold, each zone of the serpentine cooling pipe is considered a temperature-controlled zone, and the temperature difference between any two adjacent temperature-controlled zones is calculated. ; When there is a temperature difference between any two adjacent temperature control zones When the flow rate is high, zone coordination control is executed to regulate the flow rate of the cooling medium during the cooling process; conversely, intelligent rate control is executed to regulate the flow rate of the cooling medium during the cooling process. The specific content of the partition coordination control is as follows: For any temperature control zone, calculate the target flow rate for that temperature control zone, and adjust the cooling medium flow rate of that temperature control zone to the calculated target flow rate by adjusting the opening of the electric regulating valve. Each preset control cycle Real-time calculation of the temperature difference between every two adjacent temperature control zones. If the temperature difference of all adjacent temperature control zones If so, then the partition coordination control ends and intelligent rate control is executed; if continuously... Even after one control cycle, there is still a temperature difference between any two adjacent temperature control zones. If so, the adjustment coefficient is increased according to the preset ratio, and the real-time thermal stress is recalculated and compared with the maximum thermal stress threshold. The specific details of the intelligent rate control are as follows: The real-time cooling rate is calculated based on the steel frame wall temperature, and then the cooling rate deviation is calculated based on the target cooling rate curve. When the difference between the cooling rate deviation and the set deviation is within the preset fine-tuning range, the PID control algorithm is used to calculate and adjust the cooling medium flow rate; otherwise, the cooling medium flow rate is adjusted according to the preset adjustment rules. After adjusting the flow rate of the cooling medium, the real-time thermal stress is recalculated. If the recalculated real-time thermal stress meets the safety condition judgment conditions, intelligent rate control continues until the cooling process ends; otherwise, the abnormal mechanism protection is triggered.

10. The intelligent rapid circulating cooling method for a large vacuum sintering furnace according to claim 9, characterized in that, The method for updating the cooling rate curve database and multi-level control strategy by performing deviation analysis on the actual cooling rate curve and the target cooling rate curve is as follows: Outlier removal and time alignment were performed on the steel frame wall temperature and cooling medium flow rate collected in time series to obtain time-synchronized steel frame wall temperature and cooling medium flow rate. Based on the axial position of the furnace body, the furnace body is divided into a high-temperature zone, a medium-temperature zone, and a low-temperature zone; Based on the time-synchronized steel frame wall temperature and cooling medium flow rate, the initial point of deviation between the actual cooling rate curve and the target cooling rate curve is determined, and the deviation start time, initial temperature and cooling rate difference corresponding to the initial point of deviation are obtained. Starting from the initial deviation point, the real-time deviation values ​​of several deviation points are calculated at fixed time intervals to form a time-series deviation sequence; By fitting the time-series deviation sequence, the deviation type of the actual cooling rate curve is determined to be either gradual deviation or abrupt deviation, and a cooling process calibration operation is performed according to the deviation type of the actual cooling rate curve. Based on the time-series deviation sequence, the average deviation of the high-temperature zone, the average deviation of the medium-temperature zone, and the average deviation of the low-temperature zone are calculated respectively, and a deviation heatmap is generated based on the calculation results. By comparing the overall trends of the actual cooling rate curve and the target cooling rate curve, and combining the deviation type and deviation heatmap of the actual cooling rate curve, the actual cooling rate curve is corrected, and the corrected actual cooling rate curve is used to update the cooling rate curve database and multi-level control strategy.

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