An aluminum alloy direct chill casting molten aluminum leakage identification and explosion prevention system and method

Abstract

The present application relates to a kind of aluminum alloy direct-chill casting molten aluminum leakage identification and explosion-proof system and method.System includes leakage identification module, hierarchical explosion-proof cooling module, circulating water processing module, nitrogen gas recycling module and main control terminal;Leakage identification module uses wireless infrared thermal imager and fiber temperature sensor combination, realizes full leakage monitoring to the temperature data fusion of both acquisition, accurately determine molten aluminum leakage;Hierarchical explosion-proof cooling module stores cooling water in its secondary casting pit, blocks molten aluminum and water contact, cooperates two-stage liquid nitrogen nozzle to realize casting blank cooling and leakage molten aluminum rapid solidification;Circulating water processing module realizes crystallizer cooling water closed loop circulation;Nitrogen gas recycling module recycles and reuses gasified nitrogen, prevents nitrogen poisoning;Leakage molten aluminum is recycled in whole relying on irregular aluminum block.The present application simultaneously has the advantages of leakage accurate identification, molten aluminum rapid solidification, leakage convenient cleaning, nitrogen environmental protection recycling, cooling water recycling.

Description

Technical Field

[0001] This invention relates to the field of safety technology in aluminum processing production, and in particular to a system and method for identifying and preventing leaks of molten aluminum in direct-cooling casting of aluminum alloys. Background Technology

[0002] Direct cooling casting of aluminum alloys is a core process in aluminum profile production. In actual production, an insulation cover needs to be installed above the casting mold, rendering the traditional method of identifying aluminum molten metal leaks by observing the vortex on the surface of the crystallizer completely ineffective. Furthermore, the dense arrangement of casting billets makes it impossible to monitor the leakage status of individual crystallizers, resulting in serious blind spots and delayed leak identification and inaccurate location. Traditional casting processes use a single deep-well structure, with cooling water stored directly inside the well. If the aluminum molten metal leaks, it immediately comes into contact with the water, instantly generating a large amount of hydrogen and water vapor, potentially causing a violent explosion and a major safety accident. Simultaneously, leaked aluminum molten metal will spill to the bottom of the well, mixing with cooling water and impurities, solidifying and becoming difficult to clean and recover, resulting in high safety risks and low operational efficiency. Existing liquid nitrogen cooling technology lacks a recovery system, allowing nitrogen to escape directly upwards, easily causing worker poisoning and resulting in significant resource waste. Moreover, the leak identification, cooling, explosion-proof, and recovery processes are independent, lacking automated linkage control, leading to delayed emergency response and failing to meet the inherent safety requirements of direct cooling casting of aluminum alloys.

[0003] Due to the above-mentioned shortcomings, existing technologies cannot be adapted to the actual working conditions of aluminum alloy direct cooling casting sites, making it difficult to achieve accurate identification of aluminum melt leakage, root cause explosion prevention, efficient recycling and resource reuse, which seriously restricts the safe development of the aluminum processing industry.

[0004] Currently, both domestic and international aluminum processing and aluminum alloy direct-cooling casting enterprises generally lack the ability to identify signs of aluminum molten metal leakage. Due to the obstruction of the casting mold by the insulation cover and the dense arrangement of the casting billets, traditional methods relying on manual experience to identify leaks suffer from poor accuracy, slow response, and inability to accurately locate the source of the leak. This also poses a significant safety hazard during production, as molten aluminum can explode upon contact with water. Existing technologies for monitoring and preventing explosions of molten aluminum leaks have several core limitations: Chinese invention patent application number 202410538848.3 discloses a sound recognition and early warning system for aluminum molten metal leakage in a diversion plate based on a digital hydrophone, which relies on the sound of aluminum molten metal contacting water to determine the leakage. This solution is not suitable for the direct cooling casting process of aluminum alloy. Affected by the high temperature and humidity on site, equipment noise, and the obstruction of the insulation cover, the sound signal cannot be effectively collected, the accuracy of aluminum leakage identification is extremely low, and it is completely impossible to locate the leakage location.

[0005] Chinese invention patent application number 202311522740.7 discloses an infrared image recognition system for aluminum liquid leakage, which determines leakage through thermal images of the crystallizer outlet. This solution is completely ineffective in direct cooling casting scenarios. The mold plate insulation cover blocks the liquid surface, and the billet arrangement is too dense, making it impossible for infrared equipment to cover the monitoring area. Image recognition has serious lag and blind spots, making it impossible to achieve real-time leakage identification and location.

[0006] Chinese invention patent application number 202511610977.X discloses a deep well casting aluminum liquid leakage early warning system, which can only realize leakage early warning and location, without any root cause explosion prevention and emergency response functions. It still adopts the traditional single deep well cooling water structure. After the early warning, it cannot block the contact between aluminum liquid and the leaked aluminum liquid. The leaked aluminum liquid cannot be quickly solidified and easily recovered, which can easily lead to an escalation of the explosion accident.

[0007] Meanwhile, existing technologies are not adapted to the special working conditions of aluminum alloy direct cooling casting molds with covers and dense billets. There is no means of monitoring the temperature field of the inclined surface between the ingot head base, resulting in a natural blind spot for leak identification. The lack of a staged casting pit to separate water and aluminum makes it impossible to prevent the explosion of molten aluminum when it comes into contact with water from the source. There is no liquid nitrogen cooling and nitrogen circulation and recovery system, resulting in high liquid nitrogen consumption and easy nitrogen escape that can poison workers. Leaked molten aluminum scattered at the bottom of the pit cannot be recovered as a whole, making cleanup difficult and posing a high safety risk. As a result, the accuracy of leak identification, the thoroughness of explosion prevention, and the practicality of the system are seriously insufficient. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention proposes a system and method for identifying and preventing leaks in molten aluminum during direct-cooling aluminum alloy casting. It integrates precise magnetic dual-source temperature field identification (infrared thermal imager + fiber optic temperature sensor), graded pit-based explosion-proofing, dual-function liquid nitrogen cooling, closed-loop cooling water circulation, environmentally friendly nitrogen recovery, and overall recovery of leaked molten aluminum. An infrared thermal imager installed on the protective railing of the ingot-feeding platform monitors the leakage status at the crystallizer outlet. Fiber optic temperature sensors, densely arranged on an inclined surface, compensate for blind spots in the billet's obstruction, achieving blind-spot-free monitoring of the temperature field along the entire leakage path. A primary and secondary casting pit separation structure fundamentally blocks contact between molten aluminum and water, eliminating the risk of explosion from the source. Two-stage liquid nitrogen nozzles complete the billet cooling and rapid solidification of leaked molten aluminum, completely resolving the industry pain points of difficult identification of leaks, high explosion risk, difficult recovery, and nitrogen toxicity in direct-cooling aluminum alloy casting.

[0009] The present invention adopts the following technical solution: A system for identifying and preventing leaks in molten aluminum during direct-cooling casting of aluminum alloys, comprising a leak identification module, a graded explosion-proof cooling module, a circulating water treatment module, a nitrogen circulation and recovery module, a sprue platform protection assembly, and a main control terminal. The leakage identification module is installed on the ingot guide platform protection assembly at the outlet end of the crystallizer and is used to collect the temperature data of the leaked aluminum liquid at the outlet end. The graded explosion-proof cooling module is located below the crystallizer and is used to cool the billet or rapidly solidify the molten aluminum. The circulating water treatment module is connected to the graded explosion-proof cooling module and is used to supply circulating water to the graded explosion-proof cooling module. The nitrogen circulation and recovery module is connected to the graded explosion-proof cooling module and is used to circulate nitrogen to the graded explosion-proof cooling module. The ingot guide platform protective assembly is arranged around the crystallizer for safety protection and as an installation carrier; The main control terminal is connected to the leakage identification module, the graded explosion-proof cooling module, the circulating water treatment module, and the nitrogen circulation recovery module. Based on the temperature data received from the leakage identification module, it controls the operation of the graded explosion-proof cooling module, the circulating water treatment module, and the nitrogen circulation recovery module.

[0010] In addition to any of the possible implementations described above, a further implementation is provided in which the ingot-drawing platform protection assembly includes multiple ingot-drawing platform corner columns and ingot-drawing platform protective railings that are spliced ​​together.

[0011] In addition to any of the possible implementations described above, a further implementation is provided in which the leakage identification module includes a wireless infrared thermal imager with a protective housing, a strong magnetic magnet, a built-in battery, and closely spaced fiber optic temperature sensors. The infrared thermal imager is magnetically fixed to the protective railing of the ingot-drawing platform by the strong magnetic magnet, and its lens faces the crystallizer outlet end. The fiber optic temperature sensors are arranged closely along the inclined surface between the ingot-drawing head bases to collect inclined surface temperature data.

[0012] In addition to any of the possible implementations described above, another implementation is provided in which the graded explosion-proof cooling module includes a primary casting pit, a secondary casting pit, a primary liquid nitrogen nozzle, a secondary liquid nitrogen nozzle, and an irregular aluminum block. The secondary casting pit is located below the primary casting pit and is used to seal and store the crystallizer cooling water. The primary casting pit is a waterless explosion-proof space. The primary and secondary liquid nitrogen nozzles are arranged on the inner wall of the primary casting pit, and the irregular aluminum block is laid at the bottom of the primary casting pit.

[0013] In addition to any of the possible implementations described above, another implementation is provided in which three primary liquid nitrogen nozzles and three secondary liquid nitrogen nozzles are arranged in each row on each of the four walls of the primary casting pit, with the two-stage nozzles staggered.

[0014] In addition to any of the possible implementations described above, another implementation is provided in which the thickness of the irregular aluminum block is 50cm-100cm, and multiple primary drainage pipes are provided on the sidewall of the primary casting pit.

[0015] In addition to any of the possible implementations described above, a further implementation is provided in which the circulating water treatment module includes a primary drain pipe, a secondary drain pipe, a water pump, an elevated water tank, an inlet pipe, and an outlet pipe. The primary drain pipe is disposed on the side wall of the primary casting pit, the secondary drain pipe is connected between the water pump and the side wall of the secondary casting pit, the inlet pipe is disposed between the secondary drain pipe and the inlet of the water pump, and the outlet pipe is disposed between the outlet of the water pump and the elevated water tank.

[0016] In addition to any of the possible implementations described above, a further implementation is provided in which the nitrogen circulation and recovery module includes a nitrogen discharge port, a nitrogen inlet pipe, a vacuum pump, a nitrogen outlet pipe, and a nitrogen pressurization and refrigeration center. The nitrogen discharge port is located on the lower side wall of the primary casting pit. The nitrogen inlet pipe is located between the outlet of the vacuum pump and the nitrogen discharge port. The nitrogen outlet pipe is located between the inlet of the vacuum pump and the nitrogen pressurization and refrigeration center.

[0017] This invention also provides a method for identifying and preventing leaks in molten aluminum from direct-cooling aluminum alloy casting. The method is implemented using the aforementioned system and includes the following steps: S1. The infrared thermal imager of the leakage identification module fixed to the ingot guide platform protection component collects the temperature field data at the crystallizer outlet in real time. At the same time, the fiber optic temperature sensor of the leakage identification module collects the temperature field data of the inclined surface where it is located. The two types of temperature field data are wirelessly transmitted to the main control terminal simultaneously. S2. The main control terminal integrates two types of temperature data for judgment. If the infrared thermal imager detects that the local temperature at the crystallizer outlet exceeds the preset threshold, or the fiber optic temperature sensor detects that the local temperature on the inclined surface exceeds the preset threshold, and the abnormal area continues to expand, it is determined that aluminum liquid leakage has occurred, leakage alarm information is generated, and the leakage area is located; if the temperature rises slightly but does not reach the threshold, it is determined to be a suspected abnormality and the dual-source monitoring frequency is increased; if the temperature does not change significantly, it is determined to be a normal operating condition. S3. The main control terminal controls the two-stage liquid nitrogen nozzles of the graded explosion-proof cooling module to increase the liquid nitrogen injection volume, so that the leaked aluminum liquid can be quickly solidified; S4. Residual water in the primary casting pit of the circulating water treatment module is quickly discharged into the secondary casting pit through the primary drain pipe, blocking the contact between the molten aluminum and water. S5. The leaked molten aluminum solidified on irregular aluminum blocks at the bottom of the primary casting pit. The entire block was removed and remelted in the furnace. S6. The vaporized nitrogen is transported to the nitrogen pressurization and refrigeration center for processing via the nitrogen discharge port of the nitrogen circulation and recovery module and the nitrogen pump, and then supplied to the liquid nitrogen nozzle for subsequent liquid nitrogen circulation.

[0018] In addition to any of the possible implementations described above, another implementation is provided: if the infrared thermal imager detects that the local temperature at the crystallizer outlet is only slightly elevated and does not reach the set threshold, or the fiber optic temperature sensor detects that the local temperature on the inclined surface is only slightly elevated and does not reach the preset threshold, then it is determined to be a suspected abnormality. At this time, the main control terminal increases the monitoring frequency of the infrared thermal imager and the fiber optic temperature sensor.

[0019] In addition to any of the possible implementations described above, another implementation is provided in which, in step S2, the preset threshold is 100℃, and the fusion judgment logic is as follows: a single temperature field data triggers the threshold and lasts for more than 3 seconds, or both temperature field data sources show a temperature rise trend of greater than or equal to 50℃ / min, that is, a leakage response is initiated and the area of ​​the high-temperature region expands by more than 2cm per second. 2 .

[0020] Compared with the prior art, the present invention has the following beneficial effects: 1. Leakage identification with no blind spots, adaptable to on-site conditions. This invention adopts a dual-source monitoring scheme of "infrared thermal imager + fiber optic temperature sensor". The infrared thermal imager monitors the initial state of leakage at the crystallizer outlet, while the fiber optic temperature sensor is densely packed to cover the inclined surface, effectively avoiding blind spots caused by aluminum billet obstruction. Dual-source data fusion enables accurate identification and location of the entire leakage path, completely solving the identification failure problem caused by obstruction in traditional monitoring methods.

[0021] 2. Thorough explosion-proof design eliminates the risk of explosion. This invention adopts a graded casting pit separation structure, with cooling water stored independently in the secondary casting pit and the primary casting pit completely dry. This fundamentally blocks the contact between molten aluminum and water, completely eliminating the core risk of molten aluminum exploding when it comes into contact with water, and achieving inherent safety.

[0022] 3. Highly efficient and convenient aluminum molten metal recycling with no resource waste. Leaking aluminum molten metal and irregular aluminum blocks quickly solidify into one piece, which can be removed as a whole, dried, and then melted back into the furnace. No crushing or cleaning is required, the recycling process is simple, and there is no impurity pollution.

[0023] 4. The dual-circulation system is energy-saving and environmentally friendly, eliminating safety hazards. The closed-loop circulation of cooling water enables efficient use of water resources, and the closed-loop recovery and reuse of nitrogen reduces production costs and prevents nitrogen from escaping and poisoning personnel, making it suitable for harsh casting environments.

[0024] 5. Fully automated closed-loop system, significantly improving safety level. The system integrates monitoring, explosion protection, recycling, and circulation functions, eliminating the need for high-risk human intervention. It forms a complete closed loop from leak identification to emergency response, significantly improving the intrinsic safety level of aluminum alloy direct-cooling casting and making it highly practical for industrial applications. Attached Figure Description

[0025] Figure 1This is a schematic diagram of the overall structure of the aluminum alloy direct-cooling casting molten aluminum leakage identification and explosion-proof system of the present invention; Figure 2 This is a schematic diagram of the installation position of the magnetic infrared thermal imager of the present invention; Figure 3 This is a schematic diagram of the direct cooling casting of aluminum alloy casting rods according to the present invention; Figure 4 This is a block diagram of the system's working logic in this invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0027] The accompanying drawings illustrate a layer structure according to an embodiment of the present invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0028] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0029] In the description of this invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0030] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0031] The system structure of the present invention is as follows: Figure 1 As shown, the system is used to identify and alarm whether the molten aluminum at the crystallizer outlet is leaking. It includes the following modules: magnetic temperature field leakage identification module, graded explosion-proof cooling module, circulating water treatment module, nitrogen circulation recovery module, ingot derrick protection components, and main control terminal. Each module is described in detail below.

[0032] 1. Magnetic Temperature Field Leakage Detection Module The crystallizer is the core forming component of aluminum alloy direct-cooling casting. It contains high-temperature molten aluminum, which solidifies on the surface through a water-cooled wall to form a billet shell. The outlet end is where the billet is pulled out and is also a high-risk area for molten aluminum leakage. Therefore, in this invention, at the position of the iron ingot-drawing platform protective railing 17 corresponding to the outlet end of the crystallizer, a strong magnet 15 is used to magnetically fix the infrared thermal imager body 13. An infrared thermal imager shell 16 is externally fitted, and an internal battery 14 provides independent power. Figure 2As shown, adjust the angle of the infrared thermal imager lens to accurately align it with the crystallizer outlet, ensuring coverage of the entire outlet monitoring area. Under normal operating conditions, the outlet of the crystallizer only exhibits the uniform surface temperature of the solidified billet, and the temperature field distribution is stable. Once aluminum liquid leakage occurs, the high-temperature liquid aluminum overflows from the outlet, forming a localized area of ​​significant high-temperature anomaly. Its temperature amplitude and diffusion characteristics are clearly different from those under normal operating conditions, and leakage events can be accurately identified through abrupt changes in the temperature field. The dummy head is part of the dummy table, installed on the upper part of the dummy table and corresponding to the crystallizer outlet. During the initial casting stage, it is inserted into the crystallizer to receive the aluminum liquid, and then it descends at a uniform speed with the dummy table to pull the billet into shape. The inclined surface between the dummy head and the base, located directly below the crystallizer outlet and in the gap between the dummy head and the base, is the inevitable path for leaking aluminum liquid from the crystallizer outlet. Since multiple billets arranged side by side will obstruct the line of sight of the infrared thermal imager, the process of leaking aluminum liquid falling from the gap between the billets cannot be completely captured by the infrared equipment. Therefore, placing sensors in this area can compensate for the blind spots of visual monitoring. Placing multiple infrared cameras at the inclined surface position can achieve comprehensive coverage of the leakage path. On the inclined surface 10, fiber optic temperature sensors are densely arranged along the length direction. These sensors have the advantages of being resistant to electromagnetic interference, high temperature and humidity, and capable of distributed continuous and rapid temperature measurement. They are suitable for the harsh working conditions of strong electromagnetic fields and high temperature and humidity in the casting site. The spacing between each sensor is ≤5cm. The sensor probes are fixed in contact with the inclined surface. The signal cable runs along the guardrail and connects to the main control terminal 26. The infrared thermal imager is connected to the main control terminal 26 via a wireless signal. The battery life is adjusted to cover the entire casting process without the need for an external power supply. The synchronization of dual-source data is adjusted to ensure that the signal transmission delay is ≤0.5s. The fiber optic temperature sensors are densely arranged along the entire inclined surface, corresponding to the attached label 38. This module is configured to acquire temperature field signals at the crystallizer outlet using a wireless infrared thermal imager with a protective housing, and acquire temperature field signals on the inclined surface using densely packed fiber optic temperature sensors. The infrared thermal imager is attached to the iron ingot-drawing platform guardrail by a strong magnet, making installation convenient and requiring no drilling. The fiber optic temperature sensors are densely packed and fitted to the inclined surface, compensating for blind spots caused by the aluminum billet. The built-in battery provides continuous power for the entire casting process, and the dual-source data fusion ensures stable operation in high-temperature and dusty casting environments. It accurately identifies aluminum melt leaks and locates the leak area by analyzing the high-temperature anomalies in the temperature field. The infrared thermal imager housing has a high-temperature resistant and impact-resistant structure, and the built-in battery capacity is sufficient to power a single complete casting process, eliminating the need for an external power source. The infrared thermal imager is arranged one-to-one with the inclined surface, achieving comprehensive temperature field monitoring.

[0033] 2. Graded explosion-proof cooling module The system employs a separate primary and secondary casting pit structure. The secondary casting pit is a sealed container for storing the crystallizer cooling water, while the primary casting pit maintains a waterless environment, effectively preventing the molten aluminum from contacting water. Two stages of liquid nitrogen nozzles are staggered along the four walls of the primary casting pit. Under normal operating conditions, the billet is cooled at a conventional flow rate, while in case of leakage, the flow rate is increased to rapidly solidify the molten aluminum. A 50cm-100cm thick irregular aluminum block is laid at the bottom of the primary casting pit, ensuring the flow of cooling water and supporting the solidified molten aluminum for complete removal and remelting. Specifically, the primary casting pit 19 and the secondary casting pit 25 are constructed below the crystallizer 6. The secondary casting pit 25 is sealed and waterproofed, and is specifically used to store cooling water 24. On the four walls of the primary casting pit 19, three primary liquid nitrogen nozzles 20 and three secondary liquid nitrogen nozzles 21 are installed in each row, with the two levels of nozzles staggered. Irregular aluminum blocks 22 with a thickness of 50cm-100cm are evenly laid at the bottom of the primary casting pit 19. Residual water can pass through the gaps between the aluminum blocks. The two levels of liquid nitrogen nozzles are installed in each row of three, staggered on the four sides of the primary casting pit to ensure that cooling and solidification cover the entire area. Residual water can pass through the gaps between the irregular aluminum blocks quickly without affecting drainage efficiency.

[0034] 3. Circulating water treatment module Residual water is quickly drained through multiple drain pipes on the side wall of the primary casting pit, and all water is transported to the secondary casting pit for storage. Cooling water in the secondary casting pit is pumped to a high-level water tank for recirculation to the crystallizer, achieving water resource recycling. Specifically, multiple drain outlets are opened on the side wall of the primary casting pit 19, and primary drain pipes 23 are installed, all connecting to the secondary casting pit 25. The secondary casting pit 25 is connected to a water pump 29 via secondary drain pipes 27 and inlet pipes 28. The outlet of water pump 29 is connected to the high-level water tank 31, and the outlet of water pump 29 is connected to the high-level water tank 31 via an outlet pipe 30. The high-level water tank 31 is connected to the cooling water inlet of the crystallizer 6 via a water supply branch. The high-level water tank 31 is the storage place for water recovered from the secondary casting pit 25, which is purified and then resupplyed to the crystallizer to cool the aluminum billet. Figure 1 The high-level water tank 31 is set at a lower position. The water supply branch between the high-level water tank 31 and the cooling water inlet of the crystallizer 6 is not shown, forming a closed-loop circulation pipeline to ensure that the pipeline is sealed and there is no nitrogen leakage. The circulating water treatment module adopts multiple pipelines for parallel drainage to ensure that the primary casting pit is completely emptied in a short time, thus completely eliminating the possibility of aluminum molten metal contact.

[0035] 4. Nitrogen circulation and recovery module Nitrogen gas is collected through a nitrogen vent below the primary casting pit and transported to a nitrogen pressurization and refrigeration center via a nitrogen pump. After being processed into liquid nitrogen, it is circulated through pipelines to supply liquid nitrogen nozzles at all levels, preventing nitrogen from escaping upwards and poisoning workers. This also enables the reuse of nitrogen resources. Specifically, a nitrogen vent 32 is opened below the primary casting pit 19, which is sequentially connected to a nitrogen inlet pipe 33, a nitrogen pump 34, a nitrogen outlet pipe 35, and a nitrogen pressurization and refrigeration center 36. The nitrogen pressurization and refrigeration center 36 is connected to the primary liquid nitrogen nozzle 20 and the secondary liquid nitrogen nozzle 21 through a liquid nitrogen delivery pipeline 37, ensuring that the pipeline is sealed and there is no nitrogen leakage. The nitrogen circulation and recovery module operates in a completely sealed manner, with nitrogen collected from below to prevent upward diffusion. The pressurization and refrigeration center can stably convert nitrogen into liquid nitrogen to meet the needs of recycling.

[0036] 5. Ingot derrick protection components The enclosed working area is formed by splicing the corner columns of the ingot-drawing platform and the protective railing of the ingot-drawing platform to ensure the safety of personnel. At the same time, the magnetic attraction properties of the iron railing can be used to stably attract the magnetic infrared thermal imager, which can be installed without drilling and is easy to assemble and disassemble. Specifically, the corner columns 12 of the ingot-drawing platform are fixed on the casting platform 1, and the protective railing 17 of the ingot-drawing platform is assembled to form an enclosed protective area. The railing 2 and the protective net 3 are installed to provide a stable magnetic mounting carrier for the infrared thermal imager.

[0037] 6. Main control terminal debugging Connected to the signals of each module, it receives temperature field data and performs leak detection. Based on the detection result, it controls liquid nitrogen injection, drainage operations, and nitrogen recovery in a coordinated manner to achieve fully automated operation. Specifically, the main control terminal 26 is connected to the signals of each module, and the data acquisition frequency is set to 5 times / second. A temperature anomaly threshold is set: a leak is determined when the local temperature on the inclined surface exceeds 100°C and continues to expand. The normal liquid nitrogen flow rate is set to 0.8 m³ / s. 3 / min, emergency flow rate 2.5m 3 / min; Debug the drainage time of the primary casting pit to ≤10s; Debug the efficiency of nitrogen recovery and pressurization refrigeration to ensure stable liquid nitrogen circulation; Complete the linkage debugging of the entire system, and the signal transmission delay is ≤0.5s.

[0038] like Figure 3 The schematic diagram of the direct cooling casting of aluminum alloy rods shown illustrates the relative positions of the core components: the crystallizer is installed in the middle of the casting platform. After the high-temperature aluminum liquid is formed in the crystallizer, it is pulled down by the dummy head to form an aluminum rod; the corner columns of the dummy table and the guardrails are arranged around the crystallizer to form a closed safety working boundary, while providing a mounting carrier for monitoring equipment (the installation position and overall distribution of the infrared thermal imager are also shown in the figure).

[0039] As an embodiment disclosed in this invention, such as Figure 4As shown, the present invention also provides a method for identifying and preventing leaks of molten aluminum in direct-cooling casting of aluminum alloys. The method is implemented through the aforementioned system and includes: S1. The infrared thermal imager of the leakage identification module fixed to the ingot guide platform protection component collects the temperature field data at the crystallizer outlet in real time. At the same time, the fiber optic temperature sensor of the leakage identification module collects the temperature field data of the inclined surface where it is located. The two types of temperature field data are wirelessly transmitted to the main control terminal simultaneously. S2. The main control terminal integrates two types of temperature data for judgment. If the infrared thermal imager detects that the local temperature at the crystallizer outlet exceeds the preset threshold, or the fiber optic temperature sensor detects that the local temperature on the inclined surface exceeds the preset threshold, and the abnormal area continues to expand, it is determined that aluminum liquid leakage has occurred, leakage alarm information is generated, and the leakage area is located; if the temperature rises slightly but does not reach the threshold, it is determined to be a suspected abnormality and the dual-source monitoring frequency is increased; if the temperature does not change significantly, it is determined to be a normal operating condition. S3. The main control terminal controls the two-stage liquid nitrogen nozzles of the graded explosion-proof cooling module to increase the liquid nitrogen injection volume, so that the leaked aluminum liquid can be quickly solidified; S4. Residual water in the primary casting pit of the circulating water treatment module is quickly discharged into the secondary casting pit through the primary drain pipe, blocking the contact between the molten aluminum and water. S5. The leaked molten aluminum solidified on irregular aluminum blocks at the bottom of the primary casting pit. The whole thing was removed and remelted in the furnace. S6. The vaporized nitrogen is transported to the nitrogen pressurization and refrigeration center for processing via the nitrogen discharge port of the nitrogen circulation and recovery module and the nitrogen pump, and then supplied to the liquid nitrogen nozzle for subsequent liquid nitrogen circulation.

[0040] Furthermore, if the infrared thermal imager detects a slight temperature rise at the outlet of the crystallizer that does not reach the set threshold, or the fiber optic temperature sensor detects a slight temperature rise at the tilted surface that does not reach the preset threshold, it is determined to be a suspected abnormality. At this time, the main control terminal increases the monitoring frequency of the infrared thermal imager and the fiber optic temperature sensor.

[0041] Furthermore, in step S2, the preset threshold used for both types of temperature field data is 100℃. The fusion judgment logic is as follows: if a single temperature field data triggers the threshold and lasts for more than 3 seconds, or if both temperature field data sources show a temperature rise trend of greater than or equal to 50℃ / min, that is, a leak response is initiated and the area of ​​the high-temperature region expands by more than 2cm per second. 2 .

[0042] Specifically, the specific working process of this system is as follows: 1. Normal casting and monitoring After the system starts, the magnetic infrared thermal imager collects the temperature field data at the outlet of the crystallizer in real time, the fiber optic temperature sensor collects the temperature field data of the inclined surface simultaneously, the built-in battery 14 provides continuous power, and the dual-source data is wirelessly transmitted to the main control terminal 26 simultaneously; the two-stage liquid nitrogen nozzles spray liquid nitrogen at a normal flow rate to uniformly cool the aluminum casting rod 7; the cooling water 24 circulates in a closed loop between the secondary casting pit 25, the high-level water tank 31, and the crystallizer 6; the vaporized nitrogen is recovered through the nitrogen discharge port 32, treated into liquid nitrogen, and then circulated to supply the nozzles, and the primary casting pit 19 remains in a waterless state.

[0043] 2. Identification and Handling of Molten Aluminum Leaks When the infrared thermal imager detects an abnormally high temperature area at the crystallizer outlet, or the fiber optic temperature sensor detects an abnormally high temperature area on the inclined surface, and the abnormal area continues to expand, the main control terminal 26 immediately determines that the aluminum liquid is leaking: the system issues an audible and visual alarm to prompt the operators to stay away; controls the two-stage liquid nitrogen nozzles to instantly increase the flow rate to quickly cool and solidify the leaked aluminum liquid; at the same time, the first-stage drain pipe 23 is activated to quickly drain the residual water in the first-stage casting pit 19 into the second-stage casting pit 25, completely blocking the contact between the aluminum liquid and the water.

[0044] 3. Recovery of leaked molten aluminum The leaked molten aluminum landed on the irregular aluminum block 22 at the bottom of the primary casting pit 19 and quickly solidified into a whole with the aluminum block. After the temperature dropped to a safe range, the workers removed the solidified molten aluminum and the irregular aluminum block as a whole, let it dry naturally, and then put it directly into the smelting furnace for remelting without breaking it up or cleaning it.

[0045] 4. System Reset After recycling is completed, check the condition of the primary casting pit 19 and the irregular aluminum block 22. After cleaning and removing any residue, reset the system to standby mode and start the next casting operation directly.

[0046] This invention can be widely applied to the safety renovation and new construction projects of aluminum alloy direct cooling casting production lines, especially suitable for casting scenarios with covered molds, dense casting, and high requirements for accurate leakage identification, explosion-proof safety, and convenient recycling. The system has a clear structure, mature component selection, and strong engineering feasibility, and can eliminate the hidden dangers of aluminum molten metal leakage and explosion at the source, showing good prospects for widespread application.

[0047] The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention; at the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

[0048] Certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function. The terms "comprising" and "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising / including but not limited to". "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error. The following descriptions in the specification are preferred embodiments for carrying out this application; however, these descriptions are for the purpose of illustrating the general principles of this application and are not intended to limit the scope of this application. The scope of protection of this application shall be determined by the appended claims.

[0049] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a product or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a product or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the product or system that includes said element.

[0050] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0051] The foregoing description illustrates and describes several preferred embodiments of this application. However, as previously stated, it should be understood that this application is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the application concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of this application should be within the protection scope of the appended claims.

Claims

1. A system for identifying and preventing leaks of molten aluminum from direct-cooling aluminum alloy casting, characterized in that, The system includes a leak detection module, a graded explosion-proof cooling module, a circulating water treatment module, a nitrogen circulation and recovery module, a lead-in platform protection assembly, and a main control terminal. The leakage identification module is installed on the ingot guide platform protection assembly at the outlet end of the crystallizer and is used to collect the temperature data of the leaked aluminum liquid at the outlet end. The graded explosion-proof cooling module is located below the crystallizer and is used to cool the billet or rapidly solidify the molten aluminum. The circulating water treatment module is connected to the graded explosion-proof cooling module and is used to supply circulating water to the graded explosion-proof cooling module. The nitrogen circulation and recovery module is connected to the graded explosion-proof cooling module and is used to circulate nitrogen to the graded explosion-proof cooling module. The ingot guide platform protective assembly is arranged around the crystallizer for safety protection and as an installation carrier; The main control terminal is connected to the leakage identification module, the graded explosion-proof cooling module, the circulating water treatment module, and the nitrogen circulation recovery module. Based on the temperature data received from the leakage identification module, it controls the operation of the graded explosion-proof cooling module, the circulating water treatment module, and the nitrogen circulation recovery module.

2. The system according to claim 1, characterized in that, The ingot-drawing platform protection assembly includes multiple ingot-drawing platform corner columns and ingot-drawing platform protective railings that are spliced ​​together.

3. The system according to claim 2, characterized in that, The leakage identification module includes a wireless infrared thermal imager with a protective shell, a strong magnetic magnet, a built-in battery, and closely spaced fiber optic temperature sensors. The infrared thermal imager is magnetically fixed to the protective railing of the ingot-drawing platform by the strong magnetic magnet, and its lens faces the crystallizer outlet. The fiber optic temperature sensors are arranged closely along the inclined surface between the ingot-drawing head bases to collect temperature data of the inclined surface.

4. The system according to claim 1, characterized in that, The graded explosion-proof cooling module includes a primary casting pit, a secondary casting pit, a primary liquid nitrogen nozzle, a secondary liquid nitrogen nozzle, and irregular aluminum blocks. The secondary casting pit is located below the primary casting pit and is used to seal and store the crystallizer cooling water. The primary casting pit is a waterless explosion-proof space. The primary and secondary liquid nitrogen nozzles are arranged on the inner wall of the primary casting pit, and the irregular aluminum blocks are laid at the bottom of the primary casting pit.

5. The system according to claim 4, characterized in that, The primary liquid nitrogen nozzle and the secondary liquid nitrogen nozzle are arranged in three rows on each of the four walls of the primary casting pit, with the two nozzles staggered.

6. The system according to claim 4, characterized in that, The circulating water treatment module includes a primary drain pipe, a secondary drain pipe, a water pump, an elevated water tank, an inlet pipe, and an outlet pipe. The primary drain pipe is installed on the side wall of the primary casting pit. The secondary drain pipe is connected between the water pump and the side wall of the secondary casting pit. The inlet pipe is installed between the secondary drain pipe and the inlet of the water pump. The outlet pipe is installed between the outlet of the water pump and the elevated water tank.

7. The system according to claim 4, characterized in that, The nitrogen circulation and recovery module includes a nitrogen discharge port, a nitrogen inlet pipe, a vacuum pump, a nitrogen outlet pipe, and a nitrogen pressurization and refrigeration center. The nitrogen discharge port is located on the lower side wall of the primary casting pit. The nitrogen inlet pipe is located between the outlet of the vacuum pump and the nitrogen discharge port. The nitrogen outlet pipe is located between the inlet of the vacuum pump and the nitrogen pressurization and refrigeration center.

8. A method for identifying and preventing explosions of leaks in molten aluminum from direct-cooling aluminum alloy casting, characterized in that, The method is implemented using the system described in any one of claims 1-7, and includes the following steps: S1. The infrared thermal imager of the leakage identification module fixed to the ingot guide platform protection component collects the temperature field data at the crystallizer outlet in real time. At the same time, the fiber optic temperature sensor of the leakage identification module collects the temperature field data of the inclined surface where it is located. The two types of temperature field data are wirelessly transmitted to the main control terminal simultaneously. S2. The main control terminal integrates two types of temperature data for judgment. If the infrared thermal imager detects that the local temperature at the crystallizer outlet exceeds the preset threshold, or the fiber optic temperature sensor detects that the local temperature on the inclined surface exceeds the preset threshold, and the abnormal area continues to expand, it is determined that aluminum liquid leakage has occurred, leakage alarm information is generated, and the leakage area is located; if the temperature rises slightly but does not reach the threshold, it is determined to be a suspected abnormality and the dual-source monitoring frequency is increased; if the temperature does not change significantly, it is determined to be a normal operating condition. S3. The main control terminal controls the two-stage liquid nitrogen nozzles of the graded explosion-proof cooling module to increase the liquid nitrogen injection volume, so that the leaked aluminum liquid can be quickly solidified; S4. Residual water in the primary casting pit of the circulating water treatment module is quickly discharged into the secondary casting pit through the primary drain pipe, blocking the contact between the molten aluminum and water. S5. The leaked molten aluminum solidified on irregular aluminum blocks at the bottom of the primary casting pit. The entire block was removed and remelted in the furnace. S6. The vaporized nitrogen is transported to the nitrogen pressurization and refrigeration center for processing via the nitrogen discharge port of the nitrogen circulation and recovery module and the nitrogen pump, and then supplied to the liquid nitrogen nozzle for subsequent liquid nitrogen circulation.

9. The method according to claim 8, characterized in that, If the infrared thermal imager detects a small temperature rise at the outlet of the crystallizer that does not reach the set threshold, or if the fiber optic temperature sensor detects a small temperature rise at the tilted surface that does not reach the preset threshold, it is determined to be a suspected abnormality. At this time, the main control terminal increases the monitoring frequency of the infrared thermal imager and the fiber optic temperature sensor.

10. The method according to claim 8, characterized in that, In step S2, the preset threshold is 100℃, and the fusion judgment logic is as follows: a single temperature field data triggers the threshold and lasts for more than 3 seconds, or both temperature field data sources show a temperature rise trend of greater than or equal to 50℃ / min, that is, a leak response is initiated and the area of ​​the high-temperature region expands by more than 2cm per second. 2 .

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