Digitalized casting method based on additive type assembly casting mold and submerged movable sprue mold filling

Abstract

The invention belongs to the technical field of forming manufacturing, and particularly relates to a digital casting method based on an additive type assembly casting mold and submerged movable sprue mold filling, which comprises the following steps: constructing a three-dimensional model of a target casting and a casting mold thereof, and dividing the casting mold into a plurality of modules from bottom to top; slicing the casting model, and extracting lamellar geometric parameters; calculating the dynamic track and posture of the pouring pipe orifice based on the geometric parameters and a fluid model; preparing each segmentation module by adopting additive manufacturing, machining or other technologies, synchronously controlling the pouring pipe to perform submerged liquid injection in the assembly process, monitoring the liquid level position in real time and adjusting the pouring state until mold filling and assembly are completed; and finally cooling and demolding to obtain a casting. According to the method, synchronous cooperative control of casting mold construction and mold filling processes is realized, the mold filling uniformity, the structural compactness and the manufacturing flexibility of complex castings are remarkably improved, and the development of a digital and intelligent casting process is promoted.

Description

Technical Field

[0001] The present invention belongs to the field of forming manufacturing technology, and in particular relates to a digital casting method based on additive assembly casting and submerged dynamic gate filling. Background Art

[0002] Casting is one of the most representative and economical metal forming technologies in modern manufacturing, widely used in many key industrial sectors, including machinery and equipment, aerospace, automotive, energy, and shipbuilding. This method involves pouring molten metal into a prefabricated mold and cooling and solidifying it to produce the desired casting. It is particularly suitable for the integrated formation of complex structures, large variations in wall thickness, or internal hollow parts that are difficult to achieve through other processing methods. Traditional casting processes offer significant advantages in the mass-produced, low-cost production of conventional structural parts, and have long held a key position in industrial production.

[0003] As industrial products evolve toward high complexity, high performance, and high-variety, small-batch production, traditional casting processes face a host of challenges. The manufacture of complex structural castings demands not only high precision and high density, but also the adaptability of the mold structure, the stability of the pouring process, and the control of the solidification process. However, in actual production, traditional mold design and manufacturing cycles are long, changes are difficult, and they lack the flexibility to meet the personalized needs of complex component structures. Traditional gating systems are generally complex and bulky, which not only increases material waste and subsequent cleanup efforts, but also easily introduces defects such as air entrapment and turbulence, limiting the yield rate and overall quality of the castings.

[0004] To overcome the bottlenecks of traditional casting techniques, additive manufacturing (AM) has been gradually introduced into the casting industry in recent years. "Moldless rapid casting" technology is a novel casting approach that combines AM with the foundry process. The basic concept involves first using 3D modeling and layered slicing techniques, then employing AM methods (such as sand printing and stereolithography) to create complex molds or sand cores. Molten metal is then poured and formed into these cores. This method offers advantages such as eliminating the need for traditional molds, offering flexible production, short cycle times, and adaptability to complex structures, making it a key development direction for the rapid production of complex parts.

[0005] However, the current widely adopted additive manufacturing and casting combined processes are still implemented independently in separate phases and processes, with additive manufacturing first used to prepare the mold, followed by separate pouring and solidification processes. These two technologies are separated in terms of time, space, and control strategies, failing to achieve synergy and functional integration across the process chain, resulting in a significant lack of integration.

[0006] First, regarding mold preparation, while additive manufacturing offers a high degree of freedom in forming, the resulting mold structure is typically completed in one go. This prevents dynamic adjustment of the mold configuration or gradual assembly based on the filling process, resulting in a lack of process-responsive flexibility. For castings with complex structures and varying local details, relying solely on static printing to create a single mold is difficult to fully adapt to process requirements such as changes in filling speed and local solidification variations that may occur during the pouring process.

[0007] Second, during the pouring phase, the flow characteristics of liquid metal are significantly affected by the mold structure and casting geometry, and existing processes are unable to dynamically control flow field parameters based on the real-time filling status. For example, existing methods for controlling filling speed and pressure in areas with different heights or cross-sectional features are typically based on empirical design or preset parameters, lacking the ability to coordinate adjustments with mold geometry data. This increases the probability of casting defects such as insufficient local filling, gas inclusions, cold shuts, and shrinkage cavities.

[0008] In addition, due to the fragmentation of the existing process flow, traditional runner systems and riser structures are still required to ensure the flow path of the molten metal and the shrinkage compensation effect. This not only increases the mold volume and material consumption, but also reduces the final casting yield, failing to fully unleash the potential of additive manufacturing in process reduction design.

[0009] In summary, although the existing submerged casting method has improved the quality of castings and the stability of the filling process to a certain extent, the existing technology represented by this method has not yet achieved a deep integration of additive manufacturing and casting technology. The application order of the two technologies is still clear, and their respective technical advantages cannot be synergistically exerted in the same manufacturing process, which is not conducive to the efficient, intelligent and flexible manufacturing of complex structural metal castings. To address this problem, it is urgent to propose a new fusion mechanism and control strategy to achieve real-time coupling and dynamic collaborative control between the mold assembly process and the metal filling process, so as to break through the systemic limitations brought about by the separation of traditional process stages and promote casting manufacturing towards a highly integrated and digital direction. Summary of the Invention

[0010] In view of this, the present invention aims to solve the technical problems in the existing casting technology that the mold structure is statically fixed and cannot dynamically respond to the filling process, the pouring process is disconnected from the mold assembly, the control accuracy is low, and the filling quality is poor. A digital casting method based on additive assembly mold and submerged dynamic gate filling is provided, which integrates three-dimensional modeling, additive assembly, real-time liquid level monitoring and dynamic flow field control, and realizes the synchronous coordination of mold construction and metal filling process. It not only breaks through the bottlenecks of stage separation and response lag in traditional casting process, but also significantly improves the filling integrity, manufacturing efficiency and surface quality consistency of complex structure castings, and promotes the development of casting technology towards high precision, high flexibility and intelligence.

[0011] To achieve the above object, the technical solution of the present invention is achieved as follows: A digital casting method based on additive assembly casting and submersible dynamic gate filling, comprising: S1. Design of 3D model: constructing a 3D model of the target casting and a corresponding 3D model of the casting mold, wherein the 3D model of the casting is used to define the casting entity structure, and the 3D model of the casting mold is used to construct a space for filling the mold; S2. Segmentation of the mold model: dividing the mold three-dimensional model from bottom to top into a plurality of mold segmentation module models, each segmentation module constituting an assembly unit of a complete mold; S3, casting model slicing: the casting 3D model is sliced ​​layer by layer to obtain multiple casting slice layer models, and the geometric parameter data of each layer is extracted; S4. Calculating pouring tube motion control data: Based on the geometric parameter data of the casting slice layer, combined with the structural parameters and flow coefficient of the pouring tube, and based on the fluid mechanics model, iteratively solving the position-time function and attitude angle data of the pouring tube nozzle over time; S5. Preparation of segmentation modules: preparing each casting segmentation module by additive manufacturing, machining or other techniques according to the segmentation module model and casting process requirements; S6. Additive mold assembly: Based on the position-time function of the pouring nozzle in step S4, the mold segmentation modules are assembled layer by layer from bottom to top, so that their assembly height is increased synchronously with the pouring nozzle; S7, pouring and filling and motion control: During the assembly process, the metal liquid is poured and filled synchronously, and the pouring nozzle is controlled to remain submerged below the liquid surface. The position and angle of the pouring nozzle are adjusted in real time to dynamically adjust the flow field. S9. Repeat the assembly and pouring process until the casting is completed.

[0012] In an example of the present application, in step S3, the geometric parameter data of the casting slice layer includes the height, upper and lower cross-sectional areas and contour inclination data of the layer model.

[0013] In an example of the present application, in step S5, based on the segmentation module model data obtained in step S2, and combined with the assembly sequence, pouring and filling path, solidification behavior and shrinkage compensation requirements, the forming material and forming process that match the actual casting process are selected to prepare the segmentation module.

[0014] In an example of the present application, in step S6, the mold segmentation modules are assembled and positioned by structural interlocking, mechanical positioning or adhesive connection, and are sealed for waterproofing during the assembly process.

[0015] In one example of the present application, in step S7, a multi-axis motion mechanism is used to dynamically adjust the position and angle of the pouring nozzle. The multi-axis motion mechanism can respond to changes in liquid level in real time to achieve height lifting, lateral positioning and posture angle adjustment of the pouring nozzle.

[0016] In one example of the present application, the pouring pipe includes a guide valve device arranged at the end of the pipe mouth, which is used to adjust the flow rate and flow direction of the molten metal.

[0017] In one example of the present application, during the pouring process, it also includes S8: liquid level position monitoring, setting the depth range of the pouring nozzle submerged in the liquid surface, monitoring the relative position of the pouring nozzle and the liquid surface during the filling process, and adjusting the lifting speed of the pouring nozzle according to the monitoring results so that it always remains within the preset submersion depth range.

[0018] In one example of the present application, in step S8, the pouring nozzle is set to dive into the liquid surface depth range H 小 -H 大 During the pouring and filling process, if the monitoring shows that the pouring nozzle is immersed deeper than H 大 , then increase the pouring nozzle lifting speed, if the immersion depth is less than H 小 , then reduce the lifting speed of the pouring nozzle.

[0019] In one example of the present application, in step S9, steps S6 to S8 are repeated until the entire casting filling and mold assembly process is completed. After the casting is cooled and solidified, each mold segmentation module is peeled off in turn, and cleaned and post-processed to obtain the final casting.

[0020] The digital casting method described in this application, which is based on additive assembly casting and submersible dynamic gate filling, is suitable for the rapid preparation of complex-shaped metal parts.

[0021] Compared with the existing technology, the digital casting method based on additive assembly casting and submerged dynamic gate filling of the present invention has the following advantages: 1. The additive assembly mold and submerged dynamic gate filling scheme proposed in this application innovatively synchronizes the mold segmentation construction process with the dynamic pouring process of the molten metal. The mapping relationship between the mold structure and the filling behavior is constructed through 3D model slicing and geometric parameter extraction. Fluid dynamics modeling is used to calculate the motion path and angle changes of the pouring tube adapted to different hierarchical structures. During the assembly process, the liquid level is monitored in real time and the nozzle position is dynamically adjusted to ensure that the molten metal is always injected submergedly, avoiding the interference of liquid level fluctuations and impacts on the mold cavity structure. Through this closed-loop collaborative mechanism, not only common defects such as turbulence, air entrainment, and inclusions during the filling process are significantly reduced, but also the uniformity and controllability of the flow field are improved, allowing the molten metal to more smoothly fill complex or sudden structural areas, thereby ensuring the internal density and surface integrity of the casting. At the same time, the probability of flow dead spots and shrinkage cavities caused by local cross-sectional changes is reduced, enabling the entire filling process to achieve high consistency and refined operation under high-degree-of-freedom control, significantly improving the first-time pass rate and service reliability of complex castings.

[0022] 2. This application divides the overall casting structure into multiple bottom-up split modules, and selects different forming materials and manufacturing methods for personalized preparation based on the position and functional requirements of each module during the filling process. This modular construction strategy not only greatly shortens the casting manufacturing cycle and response time, but also can flexibly adjust the local structure of the casting according to the actual casting structure, effectively adapting to the personalized needs and filling path changes in the manufacturing process of complex structural parts. Through the collaborative operation of layer-by-layer construction and synchronous liquid injection, it ensures that the casting assembly rhythm is highly matched with the liquid filling state, especially in multi-variety, small batch, and high-complexity industrial manufacturing scenarios, showing significant flexible manufacturing capabilities and process adjustability.

[0023] 3. This application is based on the integration of multiple technologies such as digital modeling, motion control, flow field regulation and additive assembly, and realizes a highly integrated system design of mold construction, liquid flow and process monitoring. The entire filling process no longer relies on the traditional runner and riser system, but relies on digital path planning and real-time controlled submerged pouring method to reduce excess runner volume and metal consumption, thereby reducing material waste and subsequent cleaning burden from the source. The detachable structure of the modular mold significantly simplifies the demolding and post-processing process, and improves the surface quality and geometric restoration of the product. While maintaining manufacturing precision and flexibility, this method also provides a complete technical path reference for the casting industry to move towards a new generation of digital, intelligent and less-manned manufacturing model, enabling a fundamental transformation of traditional casting from process-driven to data-driven, and from static response to dynamic control. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1A process roadmap for a digital casting method based on additive assembly casting and submersible dynamic gate filling according to an embodiment of the present invention; Figure 2 Schematic diagram of an embodiment of the digital casting method based on additive assembly mold and submersible dynamic gate filling according to the present invention; The marks in the figure are: 1- ladle, 2- pouring pipe, 3- six-axis manipulator motion platform, 4- mold placement platform, 5- assembled mold segmentation module, 6- mold cavity, 7- mold segmentation module being assembled. DETAILED DESCRIPTION

[0025] The following will be combined with the accompanying drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of this application.

[0026] In the description of this application, it should be noted that the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments according to this application. For ease of description, the dimensions of the various parts shown in the drawings are not drawn according to the actual proportional relationship. Technologies, methods and equipment known to ordinary technicians in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, so once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0027] It should be noted that the terms "first," "second," etc. in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than those illustrated or described herein, and that the objects distinguished by "first," "second," etc. are generally of the same type, and do not limit the number of objects. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0028] It should be noted that, in the description of this application, the directions or positional relationships indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise specified, these directional terms do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of this application; the directional terms "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0029] It should be noted that, in the present application, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0030] like Figure 1 As shown, the present application discloses a digital casting method based on additive assembly casting and submersible dynamic gate filling, comprising: S1. Design of 3D model: constructing a 3D model of the target casting and a corresponding 3D model of the casting mold, wherein the 3D model of the casting is used to define the casting entity structure, and the 3D model of the casting mold is used to construct a space for filling the mold; S2. Segmentation of the mold model: dividing the mold three-dimensional model from bottom to top into a plurality of mold segmentation module models, each segmentation module constituting an assembly unit of a complete mold; S3, casting model slicing: the casting 3D model is sliced ​​layer by layer to obtain multiple casting slice layer models, and the geometric parameter data of each layer is extracted; S4. Calculating pouring tube motion control data: Based on the geometric parameter data of the casting slice layer, combined with the structural parameters and flow coefficient of the pouring tube, and based on the fluid mechanics model, iteratively solving the position-time function and attitude angle data of the pouring tube nozzle over time; S5. Preparation of segmentation modules: preparing each casting segmentation module by additive manufacturing, machining or other techniques according to the segmentation module model and casting process requirements; S6. Additive mold assembly: Based on the position-time function of the pouring nozzle in step S4, the mold segmentation modules are assembled layer by layer from bottom to top, so that their assembly height is increased synchronously with the pouring nozzle; S7, pouring and filling and motion control: During the assembly process, the metal liquid is poured and filled synchronously, and the pouring nozzle is controlled to remain submerged below the liquid surface. The position and angle of the pouring nozzle are adjusted in real time to dynamically adjust the flow field. S9. Repeat the assembly and pouring process until the casting is completed.

[0031] The present invention discloses a digital casting method based on additive assembly casting and submerged dynamic gate filling. The entire manufacturing process is based on three-dimensional digital modeling. First, a 3D model of the target casting and its matching casting mold 3D model are constructed by CAD software or three-dimensional design software. The casting 3D model corresponds to the space for obtaining metal parts by submerged dynamic gate filling in the subsequent step, and the casting mold 3D model corresponds to the space for additive assembly casting in the subsequent step. Then, according to the geometric characteristics of the casting, the casting mold assembly specification requirements and the casting process requirements, the casting mold 3D model is divided from bottom to top into multiple independently formable segmented modules. Each module is prepared separately by additive manufacturing, machining or other processes to form a casting mold structure unit for layer-by-layer assembly. At the same time, the casting model is Slicing is performed to extract geometric parameter data such as the cross-sectional area, height and contour shape of each layer. Combined with the preset pouring pipe structural parameters and the flow characteristics of the molten metal (flow coefficient), based on the principle of continuum fluid mechanics, the optimal position-time control path and posture angle change sequence of the pouring nozzle in the casting process are iteratively calculated. Then, the synchronous assembly and pouring stage is entered. During the layer-by-layer construction of the casting segmentation module, the pouring pipe is controlled to perform dynamic liquid injection at the same time, keeping its nozzle in the set depth range below the liquid surface at all times, ensuring stable liquid flow, gas isolation and uniform filling during the filling process, realizing fine control and intelligent response of the flow state, and obtaining the target casting product through cooling, demoulding and post-processing steps after the entire filling is completed. The digital casting method based on additive assembly mold and submersible dynamic gate filling described in this application takes digital design and flow field control as the core. First, a complete three-dimensional model of the mold and casting is constructed for subsequent slicing and simulation calculations. The required filling volume and geometric characteristics of each layer of the casting are obtained through layered slicing. Then, the dynamic pouring path is solved by the calculation method according to the set physical properties of the molten metal and the pouring tube parameters. In the actual assembly process, the filling position and direction of the liquid metal can be accurately controlled by the mobile pouring mechanism. In conjunction with the gradually constructed mold structure, the corresponding space is constructed while the metal liquid is filling. With the help of sensors, the relative depth between the liquid surface and the pouring gate is sensed in real time and its lifting rate is dynamically adjusted, so that the filling process is always in a stable state, realizing the coupled regulation and coordinated control of the mold structure and the liquid flow behavior.

[0032] This application deeply integrates the segmented additive assembly of casting molds with the real-time filling process, which not only avoids the defect that traditional static casting molds cannot adapt to dynamic pouring states, but also saves the volume and material costs required for conventional runner systems. By dynamically controlling the pouring path and posture, it effectively reduces turbulence, air entrainment, oxidation and other adverse phenomena in the flow of molten metal, thereby significantly improving the filling uniformity and solidification density. At the same time, the additive segmented casting assembly method improves the ability of the casting to adapt to complex structures and meets the flexible manufacturing needs of multiple varieties and small batches. The entire process is intelligently controllable and responsive, which greatly expands the manufacturability of high-performance complex castings and improves the consistency and yield of products.

[0033] As a preferred example of the present application, in step S3, the geometric parameter data of the casting slice layer includes the height, upper and lower cross-sectional areas and contour inclination data of the model. In the example of the present application, in the process of layering and slicing the casting three-dimensional model, the key geometric parameters of each slice layer are extracted, including the height, upper and lower cross-sectional areas and contour inclination data of each layer. By collecting these geometric dimension information, the flow resistance, area change trend and local tilt structure of different layers in the filling process can be more accurately reflected. In particular, in the case of castings with complex morphology or sudden changes in cross-section, the change in upper and lower cross-sectional areas directly affects the required filling volume of molten metal per unit time, and the contour inclination has a significant effect on the local flow rate and liquid surface tension. The introduction of these parameters not only improves the simulation accuracy of the subsequent pouring path, but also provides a more comprehensive basic data support for the control strategy of fluid flow and filling stability, reduces the probability of defect generation caused by local geometric mismatch, thereby promoting the adaptive optimization of the pouring path and the synchronous adjustment of the assembly process, and finally realizes the intelligent coordination of the coupling relationship between the mold construction rhythm and the filling speed, significantly improving the reliability of the overall casting process and the consistency of the finished product.

[0034] As a preferred example of the present application, in step S5, the casting segmentation module is prepared using corresponding forming materials and forming processes based on the segmentation module model data obtained in step S2, as well as the actual casting process characteristics and the process requirements of assembly, pouring, solidification, and shrinkage compensation. In the process of preparing the casting segmentation modules, the structural strength, thermal conductivity, gas dispersion performance and dimensional stability of each segmentation module are systematically evaluated in combination with the module structure data obtained in step S2 and the specific requirements of the subsequent process stages. Different types of forming materials and forming methods are selected in a targeted manner according to their installation position in the assembly process, the key flow section in the pouring and filling process, and whether they play the role of auxiliary drainage or thermal node regulation in the solidification and shrinkage compensation process. For example, high-strength heat-resistant sand materials can be used for modules located in the high-temperature and high-pressure area at the bottom, and high-resolution printing materials can be used for modules located in complex cross-sections to ensure morphological accuracy. At the same time, for areas that are easy to demold in the later stage, easily disintegrated binders can be used in combination to improve post-processing efficiency. Through this full-process adaptive preparation strategy, not only the functional synergy and structural stability of each segmentation module are guaranteed, but also a good physical basis is provided for the subsequent casting assembly process, thereby improving the operating efficiency and product quality of the overall casting system.

[0035] This application introduces a material and process selection strategy driven by process requirements in the preparation stage of the mold segmentation module, which significantly improves the mold's responsiveness to the structural characteristics and process flow of the casting, so that each module not only meets the geometric accuracy of the structural dimensions, but also has stronger functional adaptability in multiple aspects such as thermal stress control, gas escape, molding accuracy and later disassembly, thereby improving the overall consistency and reliability of the mold, reducing deformation, cracking or casting defects caused by material mismatch or a single preparation method, and taking into account engineering practicality and manufacturing controllability while maintaining a high degree of freedom of design capability. In this application, the selection of forming materials and forming processes that match the actual casting process is an adaptive selection made by those skilled in the art based on the structural characteristics of the segmentation module model and the casting process requirements, and will not be elaborated on here.

[0036] As a preferred example of the present application, in step S6, the casting segmentation module realizes assembly positioning between modules through structural interlocking, mechanical positioning or adhesive connection, and combines anti-seepage sealing measures during the assembly process to improve the inter-layer assembly accuracy and the sealing of the casting process. During the assembly process of the casting segmentation modules of the present application, in order to ensure that the modules can be firmly connected and form a continuous molding space, the modules are positioned by means of structural interlocking, mechanical limiting or adhesive fixing, and at the same time, anti-seepage sealing treatment is applied to the module joints to prevent leakage of molten metal. The structural interlocking can be achieved by pre-setting complementary concave and convex structures to achieve self-alignment positioning between modules, mechanical positioning can be achieved by pins or positioning columns during the module splicing process to achieve spatial constraints and assembly stability, adhesive connection can be used to enhance the strength of the joints and fill tiny gaps, and anti-seepage treatment can be applied between the module interfaces using materials such as high-temperature sealing strips, heat-resistant sealing coatings or powder pads, which can not only compensate for manufacturing errors between modules, but also prevent seepage or leakage of molten metal during the filling process. The above assembly method further enhances the airtightness of the pouring process on the basis of ensuring structural integrity, effectively improves the working reliability and service life of the overall casting system, and shows good operational adaptability and stability in the digital manufacturing of complex structural castings.

[0037] As a preferred example of the present application, in step S7, the height of the pouring nozzle is adjusted and the position and angle of the pouring tube are dynamically adjusted through a multi-axis motion mechanism to achieve submerged dynamic gate filling, ensuring the stability of the pouring process and the quality of the casting. During the casting filling process, the present application realizes dynamic adjustment of the position and angle of the pouring nozzle by configuring a multi-axis motion mechanism with a high degree of freedom. The multi-axis motion mechanism can not only accurately raise the height of the pouring nozzle in the vertical direction to adapt to the rising trend of the liquid level, but also perform fine-tuning in the horizontal direction to cope with the offset problem caused by the asymmetry of the casting structure or the complexity of the metal flow path. At the same time, the system also has the ability to adjust the posture angle of the pouring nozzle to optimize the jet direction of the molten metal entering the mold cavity. The multi-axis motion mechanism can adopt the industrially mature SCARA structure, six-degree-of-freedom parallel mechanism or multi-joint serial robotic arm system, etc., combined with the encoder feedback system and pressure / liquid level sensor signal to realize closed-loop control and dynamic correction. Through this integrated adjustment mechanism, the pouring tube is always in a state of being submerged in the liquid surface and stably maintains the optimal pouring distance and angle, thereby ensuring that the pouring process has a stable, uniform and predictable flow state, avoiding problems such as impact, eddy current or inclusion caused by improper inflow method.

[0038] As a preferred example of the present application, the pouring pipe includes a guide valve device arranged at the end of the pipe mouth, which is used to adjust the flow rate and direction of the molten metal to match the flow field control and mold structure adaptation during the filling process. The present application sets a guide valve device at the end of the liquid outlet of the pouring pipe. The guide valve device can adjust the injection speed and jet direction of the fluid in real time during the molten metal pouring process to adapt to the geometric structure of the casting and the dynamic requirements of the filling stage, so that the molten metal can fill the complex cavity structure according to the set path, avoiding impact or liquid level instability caused by improper jet flow. The entire control process is coordinated with the mobile platform and the liquid level monitoring system, and can perform dynamic adjustments according to the filling volume requirements and local geometric changes at different time points, thereby ensuring the continuity, uniformity and controllability of the filling process.

[0039] As a preferred example of the present application, during the pouring process, it also includes S8: liquid level position monitoring, setting the depth range of the pouring nozzle submerged in the liquid surface, monitoring and adjusting the pouring nozzle lifting speed during the filling process, so that it always remains within the set depth range. During the pouring process, in order to ensure the smooth filling of the molten metal and reduce casting defects, the present application specially introduces a liquid level position monitoring step. By presetting a reasonable submergence depth range, the system collects the distance data between the pouring nozzle and the metal liquid surface in real time through a sensor and compares it with the set range. If it is detected that the pouring nozzle submerges less than the set lower limit, its lifting speed is reduced or the lifting is temporarily stopped. If it is greater than the set upper limit, the lifting rhythm is appropriately accelerated to ensure that the pouring nozzle always remains within the submergence depth range for stable pouring. This solution effectively links the liquid level monitoring module and the pouring pipe motion mechanism through a closed-loop control method to avoid liquid level position deviation problems caused by pouring speed fluctuations or differences in mold structure, thereby maintaining a stable filling speed and pressure, and avoiding turbulence and fluctuations of the liquid metal in the mold cavity.

[0040] As a preferred example of this application, the pouring nozzle is set to be immersed in the liquid surface depth range H 小 -H 大 During the pouring and filling process, monitor the depth of the pouring nozzle into the liquid surface. If the depth is greater than H 大 , then increase the pouring nozzle lifting speed, if the immersion depth is less than H 小 , then reduce the pouring nozzle lifting speed. This application sets a reasonable pouring nozzle submerged depth range H during the pouring and filling process 小 To H 大 , and continuously monitor the actual distance between the pouring nozzle and the metal liquid surface. When the system detects that the diving depth exceeds the upper limit H 大 When the pouring pipe is immersed too deeply, the lifting speed will be automatically increased to prevent it from being immersed too deeply and causing flow interference. If the immersion depth is lower than the lower limit H 小, the pouring tube lifting speed is slowed down accordingly to prevent the nozzle from being exposed to the liquid surface and causing oxidation and splashing. The entire control process is based on a closed-loop comparison of the real-time liquid level height data and the preset interval. Combined with the pouring tube position feedback, the nozzle height is dynamically adjusted with the liquid level. While ensuring the smooth filling of the molten metal, the fluctuation caused by the change in the relative position of the nozzle and the liquid level is reduced, thereby achieving high-quality and high-consistency dynamic filling process control.

[0041] As a preferred example of the present application, in step S9, S6 to S8 are repeated until the entire casting filling and mold assembly process is completed. After the casting is cooled and solidified, the various segmentation modules of the mold are peeled off, and then cleaned and post-processed to obtain the final casting. In the later stage of the casting process, the present application ensures that the casting filling and mold construction processes are coordinated by continuously executing the layered assembly, synchronous pouring and liquid level control steps. After the casting is completed as a whole, the metal is solidified and formed according to the set cooling and solidification cycle. The segmentation modules of the mold are then peeled off in an orderly manner according to the original assembly order, and then the exposed casting is subjected to standard cleaning, polishing and necessary post-processing operations to meet the use requirements. The entire process simplifies the demoulding and cleaning process through modular management, improves the convenience of operation and reduces the mechanical interference caused to the casting surface, effectively adapts to the demoulding requirements of complex structure castings, and ensures the integrity and surface quality of the final product.

[0042] This application effectively breaks through the problems of traditional integral castings being difficult to disassemble quickly and complex castings being easily damaged during demolding through the dynamic coordination of the filling and assembly processes, the orderly stripping of modular castings and the post-processing process. On the one hand, it improves the process control accuracy and flexibility of the assembly and filling stages. On the other hand, it realizes low-disturbance operation of the demolding process through the independent stripping of the split modules, significantly reduces surface defects, dimensional deviations or structural damage caused by mold breakage and demolding, improves the first-time yield and process adaptability of high-precision castings, is conducive to achieving the small-batch rapid delivery and automated manufacturing goals of complex and high-value castings, and promotes the development of digital and intelligent casting processes.

[0043] As a preferred example of the present application, the digital casting method based on additive assembly molds and submerged dynamic gate filling is particularly suitable for the rapid manufacturing of metal parts with complex shapes, variable inner cavities, uneven wall thicknesses or fine local structures. This method accurately obtains the geometric information of complex castings through three-dimensional modeling, and uses additive manufacturing technology to divide the mold into multiple split modules and then construct them layer by layer, thereby achieving precise molding of any complex spatial structure. At the same time, with the dynamically controlled submerged pouring system, it can implement partitioned filling and flow field adjustment according to different structural features, significantly improving the filling integrity and density of complex castings. Subsequently, the mold is dismantled modularly and directional post-processing is performed to ensure that the geometric restoration and surface quality of the casting meet the design requirements. This process path provides an effective solution for the rapid manufacturing of personalized, small-batch, high-complexity metal parts, and is particularly suitable for application scenarios such as aerospace, energy equipment, and medical equipment that have extremely high requirements for structural complexity and manufacturing precision.

[0044] Example 1 like Figure 2 The figure shows an embodiment of the digital casting method based on additive mold assembly and submersible dynamic gate filling according to the present invention. In this figure, the ladle 1 is used to hold the molten metal liquid, and the pouring pipe 2 is connected below it. It is controlled by a six-axis manipulator motion platform 3 to achieve dynamic adjustment of the pouring position and angle; the mold placement platform 4 is used to support the entire mold structure, and the assembled mold segmentation module 5 constitutes a partial cavity structure, forming a mold cavity 6 inside for the metal liquid to fill and form; the mold segmentation module 7 being assembled is used to continue to build the cavity upward, realizing the coordinated control of the layer-by-layer additive mold construction and the submersible filling process. The specific implementation process is as follows: Step 1: Use NX software to draw a 3D model of a ring-shaped casting (bottom outer diameter 750mm, top outer diameter 1000mm, height 500mm, wall thickness 50mm). Based on the 3D casting model, draw a corresponding 3D mold model. The internal curved surface of the mold corresponds to the outer contour of the casting. The external dimensions of the mold are 1200mm (length) × 1200mm (width) × 650mm (height). Step 2: Split the mold 3D model from bottom to top into 11 mold segmentation module models. The first layer (i.e., bottom layer) mold module has a height of 150 mm, and the other 10 layers of mold modules have a height of 50 mm. The mold segmentation modules are combined into a mold segmentation module assembly. Step 3: Using NX software, the casting 3D model was sliced ​​and layered to obtain 10 casting slice layer models. Each slice layer model had a height of 50 mm and a contour surface inclination angle of 16°. The upper and lower cross-sectional areas of each casting slice layer model were measured. Step 4: The pouring pipe has a length of 300 mm, an inner diameter of 25 mm, and an outer diameter of 30 mm. A lateral outflow diversion valve is installed at the pouring pipe nozzle. The flow coefficient of the pouring pipe is 0.7. Based on the principles of fluid mechanics and the data of the casting slice layer model obtained in step 3, the position-time relationship of the pouring pipe nozzle at different times is obtained through iterative calculation. Based on the structural characteristics of the mold segmentation module model obtained in step 2, the deflection angle of the pouring pipe is 16°. Step 5: Based on the data of the mold segmentation module model obtained in step 2, as well as the actual casting process characteristics and the process requirements of assembly, pouring and filling, solidification, and feeding, the bottom layer of the mold segmentation module is a flat plate structure, with an iron plate with strong cooling capacity embedded in the module and coated sand wrapped on the outside. The molding material of the remaining layers of the mold segmentation module is all coated sand; Step 6: Assemble the mold segmentation modules layer by layer from bottom to top. When assembling the mold segmentation modules, attention should be paid to assembly accuracy and interlayer anti-seepage treatment. The assembly height of the mold segmentation modules increases as the pouring nozzle is raised, that is, the height of the mold is always kept a certain distance above the liquid level. Step 7: Use ZL102 molten metal to pour. During the pouring and filling process, according to the position-time relationship of the pouring nozzle obtained in step 4, the height of the pouring nozzle is adjusted by the multi-axis manipulator movement mechanism. The pouring nozzle is submerged about 25 mm below the liquid surface. The molten metal flows out from the diverter valve installed at the pouring nozzle to fill the mold cavity. Step 8: Set the pouring nozzle immersion depth range to 20mm-30mm. During the pouring and filling process, monitor the depth of the pouring nozzle submerged in the liquid surface. If the submersion depth is greater than 30mm, increase the nozzle lifting speed. If the depth is less than 20mm, reduce the pouring nozzle lifting speed. After adjustment, the pouring nozzle submersion depth is within the set submersion depth range. Repeat steps 6-8 until the entire mold assembly and casting filling process is completed; Step 9: After the pouring is completed and the casting is cooled and solidified, the various segmented modules of the mold are peeled off, and the casting is cleaned and polished to obtain the target casting.

[0045] Compared with existing technologies, this new method uses a submerged dynamic gate to pour and fill the mold during additive assembly casting, enabling the rapid preparation of complex-shaped metal parts. It fully utilizes the strengths of additive manufacturing and casting technologies, resulting in the following advantages: (1) The mold assembly and casting production methods are more flexible and the process is more controllable; (2) It can “reduce” the pouring system and improve the process yield of castings; (3) The flow field is adjustable and controllable, the filling state is good, the solidification process is optimized, and the shrinkage compensation capacity is enhanced.

[0046] The embodiments of the present application are described above in conjunction with the accompanying drawings. Unless there is a conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

Claims

1. A digital casting method based on additive assembly casting and submersible dynamic gate filling, characterized in that: include: S1. Design of 3D model: constructing a 3D model of the target casting and a corresponding 3D model of the casting mold, wherein the 3D model of the casting is used to define the casting entity structure, and the 3D model of the casting mold is used to construct a space for filling the mold; S2. Segmentation of the mold model: dividing the mold three-dimensional model from bottom to top into a plurality of mold segmentation module models, each segmentation module constituting an assembly unit of a complete mold; S3, casting model slicing: the casting 3D model is sliced ​​layer by layer to obtain multiple casting slice layer models, and the geometric parameter data of each layer is extracted; S4. Calculating pouring tube motion control data: Based on the geometric parameter data of the casting slice layer, combined with the structural parameters and flow coefficient of the pouring tube, and based on the fluid mechanics model, iteratively solving the position-time function and attitude angle data of the pouring tube nozzle over time; S5. Preparation of segmentation modules: preparing each casting segmentation module according to the segmentation module model and casting process requirements; S6. Additive mold assembly: Based on the position-time function of the pouring nozzle in step S4, the mold segmentation modules are assembled layer by layer from bottom to top, so that their assembly height is increased synchronously with the pouring nozzle; S7, pouring and filling and motion control: During the assembly process, the metal liquid is poured and filled synchronously, and the pouring nozzle is controlled to remain submerged below the liquid surface. The position and angle of the pouring nozzle are adjusted in real time to dynamically adjust the flow field. S9. Repeat the assembly and pouring process until the casting is completed.

2. A digital casting method based on additive assembly mold and submersible dynamic gate filling according to claim 1, characterized in that: In step S3, the geometric parameter data of the casting slice layer includes the height, upper and lower cross-sectional areas and contour inclination data of the layer model.

3. A digital casting method based on additive assembly mold and submersible dynamic gate filling according to claim 1, characterized in that: In step S5, based on the segmentation module model data obtained in step S2, and in combination with the assembly sequence, pouring and filling path, solidification behavior and shrinkage compensation requirements, the forming material and forming process that match the actual casting process are selected to prepare the segmentation module.

4. A digital casting method based on additive assembly mold and submersible dynamic gate filling according to claim 1, characterized in that: In step S6, the mold segmentation modules are assembled and positioned by structural interlocking, mechanical positioning or adhesive connection, and are sealed for waterproofing during the assembly process.

5. The digital casting method based on additive assembly mold and submersible dynamic gate filling according to claim 1 is characterized in that: In step S7, a multi-axis motion mechanism is used to dynamically adjust the position and angle of the pouring nozzle. The multi-axis motion mechanism can respond to changes in the liquid level in real time to achieve height lifting, lateral positioning and posture angle adjustment of the pouring nozzle.

6. A digital casting method based on additive assembly mold and submersible dynamic gate filling according to claim 1, characterized in that: The pouring pipe includes a guide valve device arranged at the end of the pipe mouth, which is used to adjust the flow rate and flow direction of the molten metal.

7. A digital casting method based on additive assembly mold and submersible dynamic gate filling according to claim 1, characterized in that: During the pouring process, it also includes S8: liquid level position monitoring, setting the depth range of the pouring nozzle diving into the liquid surface, monitoring the relative position of the pouring nozzle and the liquid surface during the filling process, and adjusting the lifting speed of the pouring nozzle according to the monitoring results to keep it within the preset diving depth range.

8. A digital casting method based on additive assembly mold and submersible dynamic gate filling according to claim 7, characterized in that: In step S8, the pouring nozzle is set to dive into the liquid surface depth range H 小 -H 大 During the pouring and filling process, if the monitoring shows that the pouring nozzle is immersed deeper than H 大 , then increase the pouring nozzle lifting speed, if the immersion depth is less than H 小 , then reduce the lifting speed of the pouring nozzle.

9. A digital casting method based on additive assembly mold and submersible dynamic gate filling according to claim 8, characterized in that: In step S9, steps S6 to S8 are repeated until the entire casting filling and mold assembly process is completed. After the casting is cooled and solidified, the individual mold segmentation modules are peeled off in sequence, and cleaned and post-processed to obtain the final casting.

10. A digital casting method based on additive assembly casting and submersible dynamic gate filling according to claim 1, characterized in that: This method is suitable for the rapid preparation of metal parts with complex shapes.

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