Metal casting resin sand mold casting process and equipment

Abstract

The invention relates to the technical field of metal material forming, in particular to a metal casting resin sand mold casting process and equipment. The process comprises the steps of mold preparation, full-automatic molding, controllable curing and integrated waste gas treatment, intelligent pouring, controllable cooling and shakeout cleaning. The equipment is a production line integrating a full-automatic molding unit, a closed curing and waste gas purification heat recovery system, an intelligent pouring unit, a modular mold system and a central control system. Quality fluctuation caused by human factors is eliminated, and large-scale stable production of castings is achieved; through in-situ integration of an efficient waste gas purification and grading heat recovery device, the problems of harmful gas emission and energy consumption of a resin sand process are solved, purified high-temperature gas serves as a process medium to be used for temperature compensation and optimization regulation and control in the intelligent pouring process, and therefore cooperation of environment protection and improvement of the internal quality of castings is achieved at the source; and the resin sand mold casting is promoted to be upgraded to high-end, green and intelligent.

Description

Technical Field

[0001] This invention relates to the field of metal material forming technology, and more specifically, to a resin sand casting process and equipment for metal castings. Background Technology

[0002] Resin sand casting is a sand casting technology that uses synthetic resin as a binder. The resin is mixed with raw sand to form molding sand or core sand, which is then hardened by a curing agent at room temperature or under heating conditions to produce metal castings. This process plays an important role in the production of complex structural castings due to its high molding accuracy and good surface quality.

[0003] However, existing conventional resin sand casting processes still have significant limitations when facing the demand for large-scale, high-quality, and highly consistent metal casting production: On the one hand, the process quality relies too much on human experience. Human factors such as mixing uniformity, compactness, and curing conditions can easily lead to fluctuations in mold strength and permeability, which in turn cause defects such as casting dimensional deviations, porosity, and sand adhesion. This makes it difficult to meet the stability and consistency requirements of casting quality in the high-end equipment field, and it is not suitable for large-scale automated production cycles. In traditional processes, the molding, curing, and box assembly stages are highly dependent on human operation, resulting in low production efficiency and poor quality control, making it difficult to achieve stable batch production while ensuring high quality. On the other hand, during the heating, curing or pouring process, the resin binder may decompose due to heat and release harmful gases such as formaldehyde and phenol, which not only deteriorates the production environment and endangers personnel health, but also requires a complex environmental protection treatment system, increasing production energy consumption and treatment costs.

[0004] Therefore, how to effectively overcome quality control fluctuations caused by human factors, adapt to the large-scale stable production needs of high-quality castings, and completely solve the problem of harmful gas emissions in the process, while retaining the high-precision advantages of resin sand molds, has become a key issue in promoting the upgrading of this technology to high-end and green. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing resin sand casting processes in terms of quality stability, large-scale automated production capacity, and harmful gas emissions.

[0006] The purpose of this invention is to provide a resin sand casting process and equipment for metal castings. By constructing a collaborative production system that integrates fully automated molding, intelligent closed-loop curing and waste gas purification and heat recovery, as well as adaptive pouring, it achieves precise and consistent control of process parameters, completely eliminating quality fluctuations caused by human factors. At the same time, based on a modular mold system and central intelligent scheduling, it achieves a balance between high efficiency and high flexibility. Furthermore, through in-situ integrated high-efficiency waste gas treatment and internal energy circulation mechanisms, it eradicates harmful gas emissions and reduces energy consumption from the source, thereby systematically solving the inherent defects of traditional processes in terms of quality stability, large-scale production capacity, and environmental pollution.

[0007] To achieve the above objectives, one objective of this invention is to provide a resin sand casting process for metal castings, comprising the following steps: Step S1: Select the corresponding modular mold components according to the target casting, and install and close the mold; Step S2: After the resin, curing agent and raw sand are precisely mixed, the mixture is automatically filled into the mold cavity, then multi-directional compaction is performed with constant process parameters, and finally the sand mold is automatically demolded. Step S3: The sand mold is sent into a closed curing environment for controlled curing. At the same time, the waste gas generated during the curing process and the subsequent pouring and cooling process is collected under negative pressure and sent to an integrated waste gas purification device for treatment. The treatment process includes a catalytic oxidation step, and the heat generated in this step is recovered and utilized. Step S4: Based on the process parameters of the target casting, adjust the pouring temperature, speed and flow rate of the molten metal in real time to complete the pouring; then perform controlled cooling on the mold after pouring. After cooling, the sand is removed and cleaned to obtain the metal casting.

[0008] As a further improvement to this technical solution, in step S1, the modular mold assembly includes a standardized base plate and a replaceable cavity module.

[0009] As a further improvement to this technical solution, in step S2, the multi-directional compaction is performed by a robot or a multi-axis servo compaction mechanism, and its pressure, path and speed are preset and controlled by the central control system according to the three-dimensional model of the mold.

[0010] As a further improvement to this technical solution, in step S3, the integrated waste gas purification device adopts a two-stage treatment process of activated carbon adsorption + catalytic oxidation, and the temperature of the high-temperature purified gas at the outlet of the catalytic oxidation reactor is above 300°C.

[0011] As a further improvement to this technical solution, in step S4, the temperature compensation adjustment using the second diverted high-temperature purified gas specifically involves: By using controllable gas nozzles arranged around the pouring nozzle or pouring stream, high-temperature purified gas is sprayed at a specific angle and flow rate onto the surface of the molten metal or the liquid flow, thereby achieving fine-tuning and uniform temperature control of the pouring temperature.

[0012] As a further improvement to this technical solution, the pouring in step S4 is performed by a pouring robot equipped with a spectral temperature measurement and vision sensor, and the pouring robot is connected to the central control system. The central control system dynamically calculates and controls the flow rate and injection parameters of the second diversion high-temperature purification gas based on real-time monitoring of the molten metal temperature, pouring flow rate, and structural characteristics of the target casting.

[0013] A second objective of this invention is to provide equipment for the resin sand casting process of metal castings described above, comprising: a fully automatic molding unit, a closed-loop curing and waste gas treatment unit, an intelligent pouring unit, a modular mold system, and a central control system, wherein: The fully automatic molding unit is used to perform sand mixing, sand filling, compaction and demolding operations; The closed curing and exhaust gas treatment unit is connected to the fully automatic molding unit, and includes a controllable curing chamber and an integrated exhaust gas purification and heat recovery system; the integrated exhaust gas purification and heat recovery system is equipped with a purified gas diversion device, which is used to divide the high-temperature purified gas generated after catalytic oxidation into a first heat recovery diversion and a second process compensation diversion. The intelligent casting unit is located downstream of the curing chamber, and a temperature compensation gas nozzle connected to the second process compensation diversion is provided on or near its casting execution mechanism. The modular mold system is used for installation in the fully automated molding unit; The central control system is connected to the signals of the above-mentioned units and is used for whole-process coordinated control, process parameter monitoring and data management, and dynamically adjusts the gas parameters of the second process compensation diversion based on the casting process model.

[0014] As a further improvement to this technical solution, the integrated waste gas purification and heat recovery system includes a waste gas collection pipe, an activated carbon adsorption tank, a catalytic oxidation reactor, a diversion valve, and at least one heat exchanger connected in sequence. The inlet of the diversion valve is connected to the outlet of the catalytic oxidation reactor; one outlet of the diversion valve is connected to the raw sand preheating pipeline or the curing chamber heating circuit through the first heat exchanger, forming the first heat recovery diversion; the other outlet of the diversion valve is connected to the temperature compensation gas nozzle of the intelligent casting unit through the heat insulation pipeline, forming the second process compensation diversion.

[0015] As a further improvement to this technical solution, the intelligent casting unit is a casting robot, whose end effector is equipped with an infrared thermometer, a vision camera and the temperature compensation gas nozzle. The casting robot is linked and controlled with the heat preservation casting furnace, and the opening, closing and flow rate of the temperature compensation gas nozzle are independently controlled by the central control system.

[0016] As a further improvement to this technical solution, the modular mold system includes a mold base plate with a unified interface and several independent cavity modules, and is equipped with an automated mold handling and positioning mechanism.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: In this resin sand casting process and equipment for metal castings, the traditional process problems that rely on manual experience, are discretely controlled, and cause serious pollution are transformed into systematic, multi-objective collaborative optimization and process integration control problems. This is achieved through the deep collaboration of a fully automatic molding unit, an intelligent closed-loop curing and waste gas purification and heat recovery system, an adaptive pouring unit, a modular mold system, and a central control system. In addition, the high-temperature gas generated after the exhaust gas purification process is used partly for preheating the raw sand and partly directly as a process medium introduced into the intelligent casting process. By controlling the local effect of this high-temperature gas on the molten metal flow, heat loss during the casting process can be effectively compensated, and the temperature distribution of the molten metal during the cavity filling process can be adjusted. This allows for more precise control of the solidification sequence of the casting, reducing defects such as incomplete filling, cold shuts, and shrinkage porosity, and further improving the internal quality of the casting. This achieves a precise closed-loop control of the entire process from raw material processing, mold preparation, in-situ purification and energy recovery of harmful gases to high-quality molding, effectively solving the industry bottlenecks that have long existed in traditional processes, such as poor quality consistency, insufficient large-scale flexible production capacity, and serious environmental pollution. Attached Figure Description

[0018] Figure 1 This is a process flow diagram of the present invention; Figure 2 This is a schematic diagram of the overall structure of the device of the present invention. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the description of this invention, it should be understood that the terms center, longitudinal, transverse, length, width, thickness, up, down, front, back, left, right, vertical, horizontal, top, bottom, inner, outer, clockwise, counterclockwise, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0021] Resin sand casting, as a precision casting technology, plays an important role in the production of complex metal structural parts. However, with the increasingly stringent requirements of high-end equipment manufacturing for casting consistency, production cycle time, and environmental protection, the traditional resin sand casting process has revealed the following inherent shortcomings: First, core process elements such as sand mixing uniformity, molding sand compaction, and solidification parameter control are highly dependent on the experience and sense of responsibility of the operators. This human intervention directly leads to fluctuations in mold strength and permeability, which in turn causes frequent defects such as out-of-tolerance casting dimensions, porosity, and sand adhesion, making it difficult to guarantee the large-scale and stable production of high-quality castings.

[0022] Second, traditional production lines have low levels of automation and intelligence, with key processes such as molding, box assembly, and casting requiring manual operation or intervention. This not only limits the production cycle and makes it difficult to meet the demands of large-scale batch production, but also makes the production line inflexible and unable to quickly respond to market changes involving multiple varieties and small batches, creating a disconnect between high quality and high efficiency.

[0023] Third, during the heating and curing process of resin adhesives and the pouring of high-temperature molten metal, pyrolysis inevitably produces volatile organic compounds (VOCs) such as formaldehyde and phenol, as well as odorous gases. Existing solutions are mostly centralized waste gas treatment at the end of the workshop, which suffers from low treatment efficiency, high energy consumption, and a tendency to cause secondary pollution in the workshop. A sharp conflict exists between environmental pressures and the inherent pollution of the process.

[0024] Therefore, please refer to Figure 1 As shown, one of the objectives of this invention is to provide a resin sand casting process for metal castings, comprising the following steps: Step S1: Select the corresponding modular mold assembly consisting of a standardized base plate and a quick-change cavity module according to the target casting, and install and close the mold.

[0025] Step S2: After the resin, curing agent and raw sand are precisely mixed, they are automatically filled into the mold cavity. Then, multi-directional compaction is performed with constant process parameters. Specifically, multi-directional compaction is performed by a robot or a multi-axis servo compaction mechanism. Its pressure, path and speed are preset and controlled by the central control system according to the three-dimensional model of the mold. Finally, the sand mold is automatically demolded.

[0026] Step S3: The sand mold is placed in a sealed curing environment for controlled curing. Simultaneously, waste gas generated during the curing process and subsequent pouring and cooling is collected under negative pressure and transported to an integrated waste gas purification device for treatment. The integrated waste gas purification device employs a two-stage treatment process of activated carbon adsorption and catalytic oxidation. The high-temperature purified gas (typically above 300℃) generated in the catalytic oxidation step is diverted for utilization: the first diverted high-temperature purified gas is used via a heat exchanger to preheat the raw sand or provide auxiliary heating for the curing environment; the second diverted high-temperature purified gas is guided through insulated pipes to the intelligent pouring unit for later use.

[0027] Step S4: Based on the process parameters of the target casting, the pouring temperature, speed, and flow rate of the molten metal are adjusted in real time to complete the pouring. During this process, the high-temperature purified gas from the second diversion in step S3 is used to perform local or global temperature compensation adjustment on the pouring stream. Specifically, through controllable gas nozzles on the pouring actuator, high-temperature purified gas is sprayed at a specific angle and flow rate onto the surface or flow of the molten metal to achieve fine-tuning and uniform temperature of the pouring temperature, thereby optimizing the temperature distribution of the molten metal within the mold cavity. The pouring is performed by a pouring robot equipped with spectral temperature measurement and vision sensors. The pouring parameters and the injection parameters of the second diversion gas are dynamically adjusted by the central control system according to the material, weight, and structural characteristics of the target casting.

[0028] The mold after pouring is then cooled in a controlled manner. After cooling, the sand is removed and the parts are cleaned to obtain the metal casting.

[0029] Please see Figure 2 As shown, a second objective of this invention is to provide an apparatus for the aforementioned resin sand casting process for metal castings. This apparatus serves as the physical embodiment of this invention. Its characteristic is that the units do not operate independently, but rather form a tightly coupled casting intelligent entity through a central control system and an integrated layout design. This entity includes: a fully automatic molding unit, a closed-loop curing and waste gas treatment unit, an intelligent pouring unit, a modular mold system, and a central control system, wherein: The fully automated molding unit is used to perform sand mixing, sand filling, compaction, and demolding operations; The closed curing and exhaust gas treatment unit is connected to the fully automatic molding unit, which includes a controllable curing chamber and an integrated exhaust gas purification and heat recovery system; The intelligent pouring unit is located downstream of the curing chamber and is used to perform adaptive pouring; Modular mold systems are designed for installation within fully automated molding units; The central control system is connected to the signals of the above-mentioned units and is used for overall process coordination control, process parameter monitoring and data management.

[0030] Furthermore, the integrated waste gas purification and heat recovery system includes a waste gas collection pipe, an activated carbon adsorption tank, a catalytic oxidation reactor, a diversion valve, and at least one heat exchanger connected in sequence. The inlet of the diversion valve is connected to the outlet of the catalytic oxidation reactor; one of its outlets is connected to the raw sand preheating pipe or the curing chamber heating circuit through the first heat exchanger, forming a first heat recovery diversion; the other outlet is connected to the temperature compensation gas nozzle of the intelligent casting unit through an insulated pipe, forming a second process compensation diversion.

[0031] The intelligent casting unit is a casting robot. Its end effector is equipped with not only an infrared thermometer and a vision camera, but also a temperature-compensating gas nozzle connected to the insulation pipeline. The casting robot is linked to the insulation casting furnace, and the opening, closing, and flow rate of the temperature-compensating gas nozzle are independently controlled by the central control system.

[0032] The modular mold system includes a mold base plate with a unified interface and several independent cavity modules, and is equipped with an automated mold handling and positioning mechanism.

[0033] In summary, this invention completely eliminates human interference through end-to-end digital control and automated execution, resulting in highly reproducible and consistent processes. The dimensional accuracy of castings can be stably controlled within CT8 level, and through active temperature field control during the pouring process, the rate of internal defects (such as shrinkage porosity and cold shuts) in key areas can be further reduced by more than 15%, providing a more reliable foundation for high-end equipment manufacturing. By setting up a highly integrated automated production line, the production cycle time per piece is significantly shortened, and overall capacity is increased by more than three times. Simultaneously, based on modular mold design and a central intelligent scheduling system, product changeover time can be reduced to less than 30% of the traditional method, thus perfectly meeting the demands of modern manufacturing for mass customization and rapid market response.

[0034] Most importantly, this invention achieves a triple synergy of environmental governance, energy recovery, and core process quality improvement. The in-situ integration of the high-efficiency purification system ensures a volatile organic compound (VOC) removal rate of over 95%, with emission concentrations far below the strictest local environmental standards. Its unique heat energy staged circulation and utilization design not only reduces the system's overall energy consumption by approximately 15-25% through methods such as preheating raw sand, but also achieves a leap from waste gas treatment and heat energy recovery to precise resource utilization and quality control by using high-temperature purified gas as a process medium for casting temperature compensation. This innovation transforms environmental protection equipment from a cost center into a quality-enabling unit, systematically solving the industry bottleneck of the difficulty in balancing green casting and high-quality requirements.

[0035] This invention constructs an intelligent closed loop that deeply couples material flow, energy flow, and information flow, realizing transparency, optimization, and full-cycle traceability of the entire production process. It is a typical practice for casting production units to move towards Industry 4.0 and has significant industry leadership and promotion value.

[0036] The following specific embodiments will further illustrate the resin sand casting process and equipment for metal castings provided by the present invention.

[0037] Example 1 This embodiment describes the production of a hydraulic valve body (material HT250).

[0038] 1. Mold preparation and system initialization: According to the hydraulic valve body drawings, the operator selects the corresponding cavity module from the modular mold library, quickly installs it onto the standard mold base plate with a unified interface, and secures it with an automatic locking mechanism. The mold assembly is transported to the molding station by a shuttle or robot. Simultaneously, the operator selects the hydraulic valve body-15kg production formula on the HMI interface of the central control system. The system automatically loads the complete set of process parameters corresponding to the formula and issues preparation instructions to each unit.

[0039] 2. Fully automatic shaping: Once the styling command is triggered, the fully automatic styling unit starts.

[0040] Sand mixing and filling: A high-precision continuous sand mixer mixes raw sand, resin, and hardener online according to the formula (e.g., 1.2% resin and 30% hardener). The mixing uniformity is monitored and adjusted by an online near-infrared spectrometer. The mixed molding sand is then transported through a closed pipeline to the sand hopper above the molding machine.

[0041] Robotic Compaction: A six-axis industrial robot carrying a specialized compaction head moves above the mold. The central control system, based on the mold's 3D model, has planned the optimal sand-filling trajectory and compaction path. The robot first performs sand-shooting and vibration actions to fill the cavity, then switches to multi-directional static pressure mode, compacting the sand mold according to preset parameters of 120 kPa pressure and 10 seconds holding time. All pressure and displacement data are uploaded to the central system in real time and compared with a standard curve to ensure consistency.

[0042] Demolding: After compaction, the robot moves away, and the demolding mechanism ejects the pre-hardened sand mold. The sand mold is automatically placed on a tray with an RFID tag and proceeds to the next stage.

[0043] 3. Controlled solidification and integrated waste gas treatment: The tray carrying the sand mold enters the closed curing and exhaust gas treatment unit.

[0044] Controlled curing: The curing chamber is divided into three temperature zones: preheating, main curing, and post-curing, with temperatures precisely controlled by a central system (e.g., 75℃, 85℃, 75℃). Circulating hot air ensures uniform heating of the sand mold, and the curing time is automatically set according to the mold thickness (150 minutes in this example). During the curing process, the resin crosslinking reaction produces waste gas containing phenol and formaldehyde.

[0045] Waste gas collection and purification: The curing chamber and subsequent casting and cooling areas are maintained under a slight negative pressure. All waste gas is drawn in real time and collected through pipelines to an integrated waste gas purification and heat recovery system.

[0046] First-stage treatment (activated carbon adsorption): The exhaust gas first passes through a pre-filter for dust removal, and then enters the activated carbon adsorption tank, where most VOCs and odors are adsorbed and removed. This adsorption tank is equipped with parallel A / B tanks, which can be switched and regenerated online to ensure continuity.

[0047] Secondary treatment (catalytic oxidation): The pretreated waste gas is fed into the catalytic oxidation reactor by an induced draft fan. Maintained by an electric heater (for initial startup) or its own reaction heat, the waste gas undergoes an oxidation reaction in the catalyst bed at 300-400℃, completely decomposing the organic matter into... and .

[0048] The specific heat recovery loop is as follows: High-temperature purified gas (approximately 350°C) generated by the catalytic oxidation reaction exits the reactor outlet and enters the hot side of a shell-and-tube heat exchanger. Simultaneously, ambient-temperature raw sand from the new sand silo flows through the cold side of the same heat exchanger via a pneumatic conveying pipeline. The high-temperature purified gas and raw sand undergo indirect heat exchange within the heat exchanger, preheating the raw sand to 50-60°C, while the purified gas temperature drops to approximately 150°C before being discharged. This preheated raw sand is then directly fed into the sand mixer. In addition, the system includes an auxiliary hot air loop, which can supplement the heating system of the curing chamber with some of the recovered heat in the form of hot air, reducing its external energy consumption. The central control system monitors the temperature at both ends of the heat exchanger and the raw sand flow rate, dynamically adjusting to optimize heat recovery efficiency.

[0049] 4. Intelligent casting and controllable cooling: The solidified sand mold is transported to the pouring station.

[0050] Intelligent Casting: The casting robot of the intelligent casting unit is in place. Its end effector integrates an infrared spectroscopy thermometer, a high-speed vision camera, and a ring-shaped controllable temperature-compensated gas nozzle, which is connected to the diversion valve of the exhaust gas treatment system via an insulated pipe. When the molten iron ladle arrives, the robot first performs non-contact temperature measurement on the molten iron inside the ladle (measuring 1380℃), and the vision system identifies the position of the pouring cup.

[0051] Pouring Temperature Compensation and Coordinated Control: The robot pours the casting according to the dedicated pouring curve for the hydraulic valve body issued by the central control system. Simultaneously, the central control system, based on the risk of cold shuts due to the thin-walled structure of the casting and real-time feedback of pouring flow and temperature data, activates temperature compensation logic. The system adjusts the diversion valve, allocating approximately 15% of the high-temperature purified gas (approximately 350°C) after catalytic oxidation to the second process compensation diversion. This gas is delivered to the annular nozzle at the end of the pouring robot. During pouring, the nozzle simultaneously sprays a uniform and controllable high-temperature gas curtain, enveloping the pouring liquid flow and forming a localized micro-atmosphere protection and thermal compensation. This operation reduces the temperature drop rate of the liquid flow in the later stages of pouring by approximately 30%, effectively ensuring the integrity of filling in the thin-walled area and significantly reducing the incidence of incomplete filling defects in the casting.

[0052] Controlled cooling: After pouring, the mold enters a forced convection cooling channel. The channel is equipped with nozzles whose wind speed and direction can be independently controlled. The central control system adjusts the cooling intensity in different zones according to the solidification simulation temperature field of the casting to achieve sequential solidification and reduce casting stress.

[0053] 5. Sand removal and data closed-loop: Once cooled to the set temperature, the mold enters a vibratory sand crusher, where the sand is broken, separating the casting from the molding sand. The casting is then removed for further cleaning. Throughout the production process, the central control system continuously collects over 200 process parameters from various sensors, including molding pressure curves, temperatures at various points in the curing chamber, exhaust gas concentration, pouring temperature curves, and cooling air velocity. These parameters are then linked to the RFID tag on the tray, creating a complete digital profile for that batch of valve body castings. This data is used for real-time quality monitoring and historical traceability, and can be continuously optimized using machine learning algorithms, forming an intelligent closed loop of production-learning-optimization.

[0054] Example 2 This embodiment is used for a rapid changeover from Embodiment 1 to the engine turbine housing (material: heat-resistant steel).

[0055] When engine turbine housing production is required, the operator switches the production formula in the central control system. The system first dispatches a mold handling robot to remove the hydraulic valve body cavity module from the current mold system and replace it with the turbine housing cavity module; this process can be completed within 30 minutes. After the formula switch, the central system automatically updates all parameters, including molding pressure parameters, curing temperature profiles, pouring temperature, pouring speed profiles, and the matching second-diversion gas compensation strategy (such as adjusting the gas injection angle to optimize the solidification gradient for thicker sections of the heat-resistant steel turbine housing). The exhaust gas treatment and heat recovery system and its diversion device automatically adapt to the new exhaust gas load and process requirements. Throughout the production changeover process, the central system coordinates all units to complete parameter resets and calibrations, ensuring production continuity and quality stability.

[0056] As can be seen from the above detailed embodiments, the present invention achieves deep linkage between various hardware and software modules through the global coordination of the central control system; and realizes closed-loop utilization of energy through specific heat recovery circuit design.

[0057] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A resin sand casting process for metal castings, characterized in that, Includes the following steps: Step S1: Select the corresponding modular mold components according to the target casting, and install and close the mold; Step S2: After the resin, curing agent and raw sand are precisely mixed, the mixture is automatically filled into the mold cavity, then multi-directional compaction is performed with constant process parameters, and finally the sand mold is automatically demolded. Step S3: The sand mold is placed into a closed curing environment for controlled curing. At the same time, the waste gas generated during the curing process and subsequent pouring and cooling process is collected under negative pressure and transported to an integrated waste gas purification device for treatment. The treatment process includes a catalytic oxidation step, and the high-temperature purified gas generated in this step is diverted for reuse. The first diversion of high-temperature purified gas is used to preheat the raw sand or provide auxiliary heating for the curing environment, while the second diversion of high-temperature purified gas is guided to the intelligent casting unit. Step S4: Based on the process parameters of the target casting, adjust the pouring temperature, speed and flow rate of the molten metal in real time to complete the pouring; During the casting process, the second diversion high-temperature purified gas from step S3 is used to locally or globally compensate and adjust the temperature of the molten metal in the casting stream or casting system in order to optimize the temperature distribution of the molten metal in the cavity. The mold after pouring is then cooled in a controlled manner. After cooling, the sand is removed and the parts are cleaned to obtain the metal casting.

2. The resin sand casting process for metal castings according to claim 1, characterized in that: In step S1, the modular mold assembly includes a standardized base plate and replaceable cavity modules.

3. The resin sand casting process for metal castings according to claim 1, characterized in that: In step S2, the multi-directional compaction is performed by a robot or a multi-axis servo compaction mechanism, and its pressure, path and speed are preset and controlled by the central control system according to the three-dimensional model of the mold.

4. The resin sand casting process for metal castings according to claim 1, characterized in that: In step S3, the integrated waste gas purification device adopts a two-stage treatment process of activated carbon adsorption + catalytic oxidation, and the temperature of the high-temperature purified gas at the outlet of the catalytic oxidation reactor is above 300°C.

5. The resin sand casting process for metal castings according to claim 1, characterized in that: In step S4, the temperature compensation adjustment using the second diverted high-temperature purified gas specifically involves: By using controllable gas nozzles arranged around the pouring nozzle or pouring stream, high-temperature purified gas is sprayed at a specific angle and flow rate onto the surface of the molten metal or the liquid flow, thereby achieving fine-tuning and uniform temperature control of the pouring temperature.

6. The resin sand casting process for metal castings according to claim 1, characterized in that: The pouring in step S4 is performed by a pouring robot equipped with a spectral temperature measurement and vision sensor, and the pouring robot is connected to the central control system. The central control system dynamically calculates and controls the flow rate and injection parameters of the second diversion high-temperature purification gas based on real-time monitoring of the molten metal temperature, pouring flow rate, and structural characteristics of the target casting.

7. An apparatus for implementing the resin sand casting process for metal castings as described in any one of claims 1-6, characterized in that, include: The system comprises a fully automated molding unit, a closed-loop curing and exhaust gas treatment unit, an intelligent casting unit, a modular mold system, and a central control system, among which: The fully automatic molding unit is used to perform sand mixing, sand filling, compaction and demolding operations; The closed curing and exhaust gas treatment unit is connected to the fully automatic molding unit, and includes a controllable curing chamber and an integrated exhaust gas purification and heat recovery system; the integrated exhaust gas purification and heat recovery system is equipped with a purified gas diversion device, which is used to divide the high-temperature purified gas generated after catalytic oxidation into a first heat recovery diversion and a second process compensation diversion. The intelligent casting unit is located downstream of the curing chamber, and a temperature compensation gas nozzle connected to the second process compensation diversion is provided on or near its casting execution mechanism. The modular mold system is used for installation in the fully automated molding unit; The central control system is connected to the signals of the above-mentioned units and is used for whole-process coordinated control, process parameter monitoring and data management, and dynamically adjusts the gas parameters of the second process compensation diversion based on the casting process model.

8. The equipment for resin sand casting process of metal castings according to claim 7, characterized in that: The integrated waste gas purification and heat recovery system includes a waste gas collection pipe, an activated carbon adsorption tank, a catalytic oxidation reactor, a diversion valve, and at least one heat exchanger connected in sequence. The inlet of the diversion valve is connected to the outlet of the catalytic oxidation reactor; one outlet of the diversion valve is connected to the raw sand preheating pipeline or the curing chamber heating circuit through the first heat exchanger, forming the first heat recovery diversion; the other outlet of the diversion valve is connected to the temperature compensation gas nozzle of the intelligent casting unit through the heat insulation pipeline, forming the second process compensation diversion.

9. The equipment for resin sand casting process of metal castings according to claim 7, characterized in that: The intelligent casting unit is a casting robot, whose end effector is equipped with an infrared thermometer, a vision camera, and the temperature compensation gas nozzle. The casting robot is linked and controlled with the heat-insulating casting furnace, and the opening, closing, and flow rate of the temperature compensation gas nozzle are independently controlled by the central control system.

10. The equipment for resin sand casting process of metal castings according to claim 7, characterized in that: The modular mold system includes a mold base plate with a unified interface and several independent cavity modules, and is equipped with an automated mold handling and positioning mechanism.

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