Casting method of base flange of wind generating set

Abstract

The invention relates to the technical field of casting equipment, in particular to a casting method for a base flange of a wind generating set, which at least comprises the following steps: a mold for the base flange is generated by adopting a 3D printing technology, and the mold is used for manufacturing and pouring a sand mold; core making of the base flange is conducted through the mold generated through 3D printing by adopting a cold core sand shooting technology, and automatic sand discharging and gas-solid hardening forming are conducted through a sand shooting machine; before pouring, technological parameters are optimized through FLOW-3D and MAGMA analysis software in the production process of the base flange casting; according to the casting process, center pouring type casting is combined with a two-stage filtering pouring cup, and molten iron is poured through center pouring type casting combined with a filtering device and used for forming a base flange casting.

Description

Technical Field

[0001] This invention relates to the field of casting technology, and in particular to a casting method for a wind turbine generator base flange. Background Technology

[0002] In the production process of wind turbine base flange castings, the steps of sand mold strength adjustment, sand injection molding, curing treatment, mold removal, sand box adaptation, positioning and casting need to be strictly connected. However, there are technical contradictions in actual operation: when adjusting the sand injection amount and cold core sand ratio, in order to meet the requirements of high-strength sand mold, the sand injection amount needs to be increased and the ratio optimized. However, the high-strength ratio may lead to a decrease in the fluidity of cold core sand, affecting the uniformity of filling when the sand injection machine injects into the mold cavity, which in turn causes internal defects in the sand mold, such as air holes or looseness.

[0003] During the curing process, the gas-solid hardening device needs to ensure that the sand mold is cured quickly to improve production efficiency. However, rapid curing may cause the hardening rate of the sand mold surface and the interior to be inconsistent, resulting in dimensional deviation of the cured sand mold or accumulation of internal stress, which affects the accuracy of mold removal.

[0004] When using universal sand boxes to fit medium and small wind turbine castings, fixed-specification sand boxes simplify inventory management, but they are difficult to fully match different casting shapes, causing deviations in the positioning device during precise positioning and affecting casting accuracy.

[0005] These contradictions are particularly prominent in the production of high-precision wind power castings. How to ensure the strength of the sand mold, the molding quality, the uniformity of solidification, the compatibility of the sand box, and the casting accuracy, while taking into account both production efficiency and casting quality, has become an urgent technical problem to be solved. Summary of the Invention

[0006] The purpose of this invention is to overcome the defects in the prior art and provide a casting method for the base flange of a wind turbine generator set.

[0007] To achieve the above objectives, the technical solution of the present invention is to design a casting method for a wind turbine generator base flange, which includes at least the following steps: using 3D printing technology to generate a mold for the base flange, wherein the mold is used to make a sand mold for casting the above. The mold generated by 3D printing is used to make the core of the base flange using cold core sand shooting technology. The sand is automatically discharged and gas-solid hardened by the sand shooting machine. Before casting, the process parameters of the base flange casting production process were optimized using FLOW-3D and MAGMA analysis software. The casting process employs a central pouring casting combined with a two-stage filtration casting cup. Molten iron is poured through the central pouring casting combined with the filtration device to form the base flange casting.

[0008] A further preferred technical solution is that the base flange mold includes an upper mold, a middle mold, a lower mold, and a sand core mold, and the upper mold core, middle mold core, lower mold core, and sand core are made by using the corresponding molds.

[0009] In a further preferred technical solution, the 3D printed mold is made of high-strength material, and the surface of the mold substrate is polished to form the first surface of the mold; a wear-resistant coating is applied to the first surface of the mold to generate the second surface of the mold; a microstructure texture is preset on the second surface of the mold, and regular micron-level grooves are formed by laser engraving technology to generate the third surface of the mold.

[0010] A further preferred technical solution involves optimizing process parameters using casting process analysis software, including: simulating molten iron flow using FLOW-3D software, whereby the simulation is used to determine pouring parameters; analyzing the sand mold solidification process using MAGMA software, whereby the analysis is used to adjust the cold core sand ratio; optimizing the gating design based on the simulation results, whereby the design reduces casting defects; and verifying the casting quality, whereby the verification includes ultrasonic flaw detection and magnetic particle testing.

[0011] A further preferred technical solution involves pouring molten iron using a center-pour casting combined with a filtration device, comprising: adopting a center-pour casting channel design, wherein the channel guides the molten iron into the sand mold; setting a two-stage filtration cup in the casting channel system, wherein the cup is used to intercept impurities in the molten iron; controlling the molten iron pouring speed, wherein the speed is determined according to the size of the sand mold; and optimizing the molten iron flow through a grouting channel, wherein the optimization improves the utilization rate of the molten iron.

[0012] A further preferred technical solution involves setting a two-stage filtration pouring cup in the gating system, including: setting a primary filter screen in the pouring cup, the filter screen being used to initially intercept impurities; setting a secondary ceramic filter layer after the primary filter screen, the filter layer being used to further purify the molten iron; monitoring the flow state of the molten iron in the pouring cup, the monitoring being used to adjust the position of the filtration device; and adjusting the filter screen aperture according to the casting size, the aperture ensuring smooth flow of molten iron.

[0013] A further optimized technical solution involves first placing the pre-mixed sand and binder mixture into the sand storage bin of the sand shot machine. The sand shot machine then uses high-pressure airflow to inject the mixture into the cavity of the mold plate. After injection, curing gas is immediately introduced to initiate preliminary curing.

[0014] In a further preferred technical solution, the cold core sand is a pre-mixed mixture of sand and binder. The sand injection machine injects the cold core sand into the mold cavity according to the preset mold plate specifications. After injection, a curing gas is introduced into the mold cavity through a gas-solidification device to generate a pre-cured sand mold. The pre-cured sand mold is then subjected to gas-solidification hardening treatment. The gas-solidification device continuously introduces curing gas, controls the gas flow rate and pressure, and generates a molding sand mold with a preset strength.

[0015] The advantages and beneficial effects of this invention are as follows: It provides a comprehensive optimization scheme for balancing efficiency, quality, and cost in the casting process of wind turbine generator base flanges, solving the problems of low production efficiency, numerous casting defects, and high costs in traditional casting processes. By employing cold-core sand injection technology combined with 3D printed molds, the sand injection volume and mold durability are optimized, ensuring rapid forming of large castings while maintaining dimensional stability. The center-pouring casting and dual-stage filtration gating cup design effectively intercept impurities, optimize molten iron flow, improve casting surface quality, and reduce the sand-to-iron ratio. Using FLOW-3D and MAGMA analysis software to simulate the molten iron flow and solidification process, the sand mold strength and gating design are adjusted to eliminate defects found in ultrasonic testing and magnetic particle inspection. The use of a universal sand box and an automated scheduling system reduces forklift operations and improves production efficiency. This invention significantly improves casting quality and production efficiency, reduces production costs, and provides the wind power industry with an efficient, high-quality, and low-cost casting technology solution. Attached Figure Description

[0016] Figure 1 This invention relates to a sand-shooting mold for the base flange of a wind turbine generator set. Figure 2 This invention relates to a sand-shooting mold for the base flange of a wind turbine generator set. Figure 3 This invention relates to a sand-shooting mold for the lower flange of a wind turbine generator base. Figure 4 This invention relates to a wind turbine generator base flange casting system; Detailed Implementation

[0017] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0018] A casting method for a wind turbine generator base flange, wherein the mold for the base flange is generated using 3D printing technology. Specifically, the base flange includes an upper mold, a middle mold, a lower mold, and a sand core mold. The mold is used to create the sand mold for casting. The mold is manufactured using 3D printing technology.

[0019] The mold design data is obtained from the preset 3D printing equipment to generate a mold prototype. The surface of the mold prototype is subjected to gas-solid treatment to form a hardened layer. The thickness of the hardened layer is controlled within a preset range to ensure the rigidity of the mold. Cold core sand is injected into the mold, and sand mold forming is completed by a sand injection machine. After the sand mold is formed, it is cured by gas-solid method to generate a cured sand mold. The surface of the cured sand mold meets the precision requirements of the casting.

[0020] When obtaining mold design data from pre-set 3D printing equipment, such as in the production of wind turbine generator base flanges, the design data includes the geometry and dimensional parameters of the base flange. By using molding technology to ensure that the prototype accuracy reaches the millimeter level, this can bring about the useful technical effects of high resolution mold prototypes and rapid iteration.

[0021] It should be noted that the principle of using gas-solid treatment to form a hardened layer on the surface of the mold prototype, with the thickness of the hardened layer controlled within a preset range to ensure the rigidity of the mold, is to strengthen the surface using a gas-assisted chemical reaction, such as using a curing agent sprayed in a nitrogen environment, so that a uniform protective layer is formed on the surface of the prototype, avoiding the risk of deformation in subsequent sand molding. This can bring about the useful technical effect of enhancing the durability and stability of the mold.

[0022] In one embodiment, the mold prototype after hardening layer treatment is fixed in a universal sand box. The universal sand box is classified according to preset specifications through standardized size design. For example, the sand box is divided into small and medium sizes. The mold prototype and the sand box are precisely aligned by positioning pins to ensure the stability of the mold in the sand box. This can bring useful technical effects of reducing assembly errors and improving reusability.

[0023] Specifically, the method of injecting cold core sand into a general sand box and completing the sand mold formation by a sand shooting machine is to uniformly fill the sand box cavity with high-pressure sand shooting. For example, for wind power flange products, the sand shooting machine injects cold core sand mixed with a curing agent at a constant pressure. After the sand mold is formed, it is cured by gas solidification. The process of generating a cured sand mold involves gas purging to accelerate the hardening reaction. This can bring useful technical effects such as shortening the curing cycle and improving the strength of the sand mold.

[0024] It should be noted that the reason why the surface quality of the solidified sand mold meets the precision requirements of the casting is due to the fine particle distribution of the cold core sand. For example, in actual casting, the surface roughness is controlled at a low Ra value to avoid casting defects. This can bring about useful technical effects such as improving the surface finish of the casting and reducing the amount of post-processing.

[0025] The 3D printed mold is made of a high-strength material, which ensures the mold's dimensional stability and durability during multiple sand-shooting cycles.

[0026] A high-strength polymer material is used to fabricate the mold substrate via 3D printing technology. This material is composed of reinforcing fibers and resin composites, ensuring the mold can withstand high pressure without deformation during sand-shooting. The mold substrate surface is polished to form the first mold surface. A wear-resistant coating, formed by plasma spraying and containing ceramic particles to enhance wear resistance, is applied to the first mold surface to create the second mold surface. The second mold surface maintains dimensional stability during multiple sand-shooting cycles. A microstructure texture is pre-set on the second mold surface, and regular micron-level grooves are formed using laser engraving technology to create the third mold surface. This microstructure texture reduces the adhesion of sand particles to the mold surface during sand-shooting. The third mold surface is periodically inspected, and surface morphology data is acquired using an optical scanner to determine the wear degree of the microstructure texture, generating wear distribution characteristics. These wear distribution characteristics are used to evaluate the dimensional stability and durability of the mold during multiple sand-shooting cycles.

[0027] The specific generation steps are as follows: a mold matrix is ​​prepared by using high-strength polymer material through 3D printing technology. The material is composed of reinforcing fibers and resin composites to ensure that the mold can withstand high pressure without deformation during the sand shooting process.

[0028] In this composite material, reinforcing fibers such as carbon fiber or glass fiber are mixed with epoxy resin and deposited layer by layer to build the mold matrix. The fibers provide tensile strength while the resin ensures adhesion, thus maintaining structural integrity during high-pressure sandblasting.

[0029] In the cold core process of wind turbine generator base flange, this substrate can withstand a pressure of several thousand Pascals per cycle, avoiding thermal deformation problems and helping to extend the service life of the mold. The surface of the mold substrate is polished to form the first surface of the mold. This process uses diamond abrasives to remove rough spots and improve smoothness for subsequent coating adhesion.

[0030] If the initial roughness of the substrate is several micrometers, it can be reduced to the submicrometer level after polishing, which helps the coating to be evenly distributed and enhances the overall durability.

[0031] In one embodiment, a wear-resistant coating is applied to a first surface of the mold, formed by a plasma spraying process, the coating comprising ceramic particles to enhance wear resistance, to form a second surface of the mold.

[0032] Specifically, plasma spraying involves heating ceramic particles, such as alumina or tungsten carbide, to a molten state and then spraying them at high speed onto a surface to form a dense layer. The process includes preheating the surface to improve adhesion, spraying multiple layers to control thickness, and cooling to cure the coating.

[0033] During sand-shooting cycles, this coating resists abrasive friction, reducing surface wear and maintaining mold dimensional accuracy after multiple uses, thus contributing to stable cold-core sand molding. The second surface of the mold maintains dimensional stability across multiple sand-shooting cycles because the high hardness of the ceramic particles disperses stress and prevents localized deformation.

[0034] In actual production, if an uncoated mold deforms after dozens of cycles, this coating can increase its durability several times over, supporting the efficient operation of automated production lines.

[0035] In one possible implementation, a microstructure texture is pre-set on the second surface of the mold, and regular micron-level grooves are formed by laser engraving technology to generate the third surface of the mold.

[0036] Specifically, laser engraving technology uses a high-energy laser beam to precisely remove material and form a groove pattern with controlled depth. The process includes scanning the surface to map the area, adjusting the laser power to achieve uniform etching, and verifying texture consistency.

[0037] During sand blasting, these grooves guide the flow of sand particles, reducing adhesion and accumulation, thereby decreasing the frequency of mold cleaning and maintaining surface integrity, which is beneficial for improving the surface quality of castings. The microstructure texture is used to reduce the adhesion of sand particles to the mold surface during sand blasting because the grooves provide escape channels and prevent sand particles from becoming embedded.

[0038] In wind turbine flange production, this texture can significantly reduce adhesion, ensure dimensional stability of the mold during continuous cycles, and support automated movement of universal sandboxes.

[0039] In one possible implementation, the third surface of the mold is periodically inspected, surface morphology data is acquired using an optical scanner, the wear degree of the microstructure texture is determined, and wear distribution characteristics are generated.

[0040] Optical scanners capture three-dimensional data using the principle of laser triangulation. This process includes calibrating the instrument to ensure accuracy, scanning the entire surface to collect point cloud data, and processing the data to identify wear areas such as variations in groove depth.

[0041] During the evaluation, if localized wear is detected, this characteristic can guide maintenance decisions, prevent sudden failures, and benefit the overall durability of the mold. The wear distribution characteristic is used to assess the dimensional stability and durability of the mold over multiple sand-shooting cycles because it quantifies the degree of texture degradation, supporting predictive maintenance.

[0042] In a production environment, this testing can extend mold changeover intervals, ensuring that the high-strength materials of 3D printed molds continue to function during the cold core process.

[0043] The core-making process of the wind turbine generator base flange is carried out using cold core sandblasting technology through the 3D-printed upper mold, middle mold, lower mold, and sand core mold. (Refer to...) Figure 1-3 As shown, the upper mold core, middle mold core, lower mold core and sand core are made. The sand is automatically fed into the mold by a sand shooting machine and then hardened by gas solidification. The core making cycle is controlled within 5 to 6 minutes.

[0044] The cold core sand, a pre-mixed mixture of sand and binder, is automatically dispensed using a sand-shooting machine. The sand-shooting machine injects the cold core sand into the mold cavity according to a pre-defined mold plate specification. After injection, a curing gas is introduced into the mold cavity through a gas-solidification device to generate a pre-cured sand mold. The pre-cured sand mold undergoes gas-solidification hardening treatment, with the gas-solidification device continuously supplying curing gas and controlling the gas flow and pressure to ensure complete reaction of the binder inside the sand mold, generating a molded sand mold with a pre-defined strength. The molded sand mold is then removed from the mold plate and stored in a fixed-specification universal sand box using an automated mold-lifting device. This universal sand box is classified and transported through a pre-defined automated scheduling system, generating sand mold components suitable for casting. In one embodiment, the automated sand feeding process using a sand-shooting machine ensures that the sand is evenly distributed in the mold cavity. This method is effective in quickly filling complex-shaped flange base structures, thereby improving the overall core-making efficiency.

[0045] When producing the base flange of a wind turbine generator set, the pre-mixed sand and binder mixture is first placed into the sand storage bin of the sand shot machine. The sand shot machine uses high-pressure airflow to inject the mixture into the cavity of the mold plate. After injection, curing gas is immediately introduced to start the initial curing. The beneficial effect of doing this is to reduce manual intervention and shorten the waiting time, which supports the control of the core making cycle.

[0046] It should be noted that the cold core sand uses a pre-mixed sand and binder mixture, which means that silica sand is used as a base material and mixed with polyurethane binder in a specific ratio. The process of automatically injecting this mixture into the mold cavity in the sand shooting machine includes sand shooting action under air pressure control. After the sand mold is pre-cured, its surface smoothness is improved, which is beneficial to the uniformity of subsequent hardening treatment. From multiple perspectives, this pre-curing can prevent the sand mold from deforming during transfer and support the continuity of automated production.

[0047] When performing gas-solid hardening treatment on the pre-cured sand mold, the gas-solid device continuously introduces gas such as triethylamine. The gas flow rate and pressure are controlled by adjusting the valve to ensure that the binder inside the sand mold reacts completely to generate a molded sand mold with a preset strength. This is done to enhance the compressive strength of the sand mold.

[0048] In the core-making process of flange bases, if the gas flow rate is too low, it may lead to uneven hardening. However, through precise control, it can bring about the beneficial effect of uniform hardening, which in turn supports the improvement of the surface quality of the casting and avoids the problem of thermal deformation in traditional resin sand.

[0049] In the aforementioned cold core sand-shooting technology, the sand-shooting volume can be increased by adjusting the parameters of the sand-shooting machine, and the sand-shooting volume meets the requirements of large castings for wind turbine base flanges.

[0050] By adjusting the sand-shooting parameters of the sand-shooting machine, the large-size requirements of the wind turbine base flange casting are obtained from the sand-shooting machine control system to determine the sand-shooting volume threshold. The threshold is calculated based on the casting volume and sand mold filling density to generate sand-shooting volume control parameters. Based on the sand-shooting volume control parameters, the nozzle pressure and sand-shooting speed of the sand-shooting machine are adjusted to generate sand mold filling density distribution data, which reflects the compactness of the sand mold in different areas. For the sand mold filling density distribution data, the finite element analysis method is used to simulate the stress distribution of the sand mold during the casting process to generate sand mold stability assessment results. Based on the sand mold stability assessment results, the sand-shooting machine parameters are optimized, and the sand-shooting volume is adjusted to a stable filling state that meets the requirements of the large wind turbine base flange casting.

[0051] In one possible implementation, the process of adjusting the sand-shooting parameters through the sand-shooting machine first involves obtaining the large size requirements of the wind turbine base flange casting from the sand-shooting machine control system. When the casting diameter reaches several meters, the system extracts volume information to calculate the required amount of sand, thereby determining the sand-shooting threshold. This threshold is set based on the product relationship between the casting volume and the sand mold filling density to ensure that the sand mold can uniformly cover the large casting structure. This results in a more stable sand mold formation and avoids voids in the large casting during molding.

[0052] After generating the sand injection quantity control parameters, these parameters will guide subsequent adjustments. For example, in actual operation, if the casting volume is large, the parameters will indicate to increase the amount of sand to match the requirements and form a more reliable sand mold base, which helps to improve the overall casting efficiency. The process of adjusting the nozzle pressure and sand injection speed of the sand injection machine according to the sand injection quantity control parameters will generate sand mold filling density distribution data. This data is collected by sensors to reflect the compactness of different areas of the sand mold.

[0053] In the flange edge area, if the pressure is adjusted to a suitable level, the density distribution will appear uniform and compact, thereby reducing the occurrence of defects. This has the beneficial effect of improving the surface quality of the casting and further supporting the stability of large casting production.

[0054] Before casting, the molding sand mold is removed from the mold plate and stored in a universal sand box of fixed specifications using an automated mold-removing device. The universal sand box is classified and transported by a preset automated scheduling system. This system is a PLC-controlled conveyor line that includes sensors to detect the position of the sand box and automatically transport it to the storage area, generating sand mold components that can be used for casting. The benefits of doing this are to reduce forklift scheduling and improve the smoothness of the production line.

[0055] On the wind power flange production line, the sand box specifications are standardized to a standard size, which facilitates automated use and indirectly supports the improvement of overall efficiency.

[0056] The upper mold core, middle mold core, lower mold core and sand core are placed in the sand box for base flange casting. Before casting, the casting production process is optimized by using FLOW-3D and MAGMA analysis software to optimize process parameters. The optimized gating design is used to reduce the sand-to-iron ratio and casting defects.

[0057] The casting process was simulated using FLOW-3D software to obtain the internal flow field distribution and solidification characteristics of the casting. This identified areas in the initial gating design that might lead to porosity and shrinkage defects, generating the first flow field distribution data. Based on this data, MAGMA software was used to analyze the temperature field changes during the casting solidification process to optimize the heat conduction performance of the sand mold, generating the first temperature field distribution data. According to this data, the intermediate gating system design was optimized, adjusting the sprue and the structure of the dual-stage filter gating cup to reduce the sand-to-iron ratio and minimize slag-blocking defects, generating the second gating design scheme. Using this second gating design, the casting process was simulated again using FLOW-3D software to verify the reduction in internal defects, generating the final flow field distribution data.

[0058] By simulating the casting process using FLOW-3D software, the flow behavior of molten metal can be analyzed in detail. For example, in the casting of the base flange of a wind turbine generator, the software calculates the velocity distribution and turbulence intensity of the liquid metal as it enters the cavity from the gate. This can identify areas of uneven flow and help to detect potential porosity early, thereby improving the quality of the casting.

[0059] The process of analyzing temperature field changes using MAGMA software based on the first flow field distribution data includes loading the flow field results as input and then simulating heat conduction and solidification dynamics. This can optimize the cooling efficiency of the sand mold and help control the solidification rate to prevent crack formation.

[0060] It should be noted that the MAGMA software focuses on casting solidification simulation. Its analysis process uses the finite volume method to solve the heat balance equation and gradually generate temperature field distribution data, thereby achieving uniform solidification and reducing scrap rate.

[0061] Reference Figure 4 As shown, the casting process adopts a center-pouring casting combined with a two-stage filtration pouring cup. The pouring cup is used to optimize the flow of molten iron and the slag-blocking effect to improve the quality of the casting.

[0062] The geometric parameters of the molten iron flow channel in the center-pour casting process are obtained from the casting design. Combined with the structural characteristics of the two-stage filter cup, an initial model of molten iron flow is constructed. The flow field distribution of molten iron during the center-pour casting process is simulated using FLOW-3D software, generating flow field velocity distribution data. The velocity change trend of molten iron flowing through the two-stage filter cup is extracted from this data. The resistance effect of the filter screen on the molten iron flow is analyzed. The aperture of the first and second stage filter screens in the two-stage filter cup is adjusted to generate optimized flow field velocity distribution data. The turbulence characteristics of molten iron during the casting process are extracted from this optimized data to determine whether the turbulent region affects the slag-blocking effect. The geometry of the two-stage filter cup is adjusted based on the turbulence characteristics to generate turbulence-optimized cup design parameters. The stability and slag-blocking efficiency data of the molten iron flow are extracted from these optimized cup design parameters. Combined with the flow channel design of the center-pour casting process, the optimized molten iron flow and slag-blocking effect are verified in FLOW-3D software, generating casting process parameters that meet the casting quality requirements.

[0063] Geometric parameters of the molten iron flow channel in center-pouring casting are obtained from the casting design. These parameters include the length and cross-sectional shape of the channel. Combined with the structural characteristics of the two-stage filter cup, such as the arrangement of the two-stage filter screen, an initial model of molten iron flow is constructed. This ensures that the model accurately reflects the actual casting environment and is beneficial to the reliability of subsequent simulations. The flow field distribution of molten iron in center-pouring casting is simulated using FLOW-3D software. FLOW-3D software is a computational fluid dynamics tool that simulates fluid flow by solving the Navier-Stokes equations through mesh generation and the finite volume method, generating flow field velocity distribution data. This helps to identify potential flow problems and optimize the process.

[0064] In one possible implementation, the velocity change trend of molten iron flowing through the double-stage filter casting cup is extracted from the flow field velocity distribution data. For example, the velocity slows down at the first-stage filter screen and tends to stabilize at the second stage. The influence of the filter screen on the resistance of molten iron flow is analyzed. This analysis is achieved by comparing the velocity gradient under different mesh sizes, which is beneficial to reducing the entrainment of impurities in the molten iron. Adjusting the mesh size of the first and second-stage filter screens of the double-stage filter casting cup, such as making the first-stage mesh slightly larger to initially filter large slag particles and the second-stage mesh smaller for fine filtration, generates optimized flow field velocity distribution data, which can improve the overall slag-blocking effect and maintain the uniformity of molten iron flow.

[0065] Turbulent characteristics of molten iron during casting are extracted from the optimized flow field velocity distribution data. These characteristics include the intensity and distribution area of ​​local eddies. It is determined whether the turbulent region affects the slag-blocking effect. For example, if turbulence causes slag back-rolling, optimization is required. The geometry of the two-stage filter cup is adjusted according to the turbulent characteristics, such as adding a conical inlet to smooth the flow. Turbulence-optimized cup design parameters are generated, which helps to reduce the defect rate and improve the internal quality of the casting.

[0066] The stability and slag-blocking efficiency data of molten iron flow are extracted from the turbulence-optimized pouring cup design parameters. For example, stability is evaluated by the fluctuation range of flow velocity, while slag-blocking efficiency is measured by the slag capture rate in the simulation. Combined with the flow channel design of the center-pouring casting process, the optimized molten iron flow and slag-blocking effect are verified in FLOW-3D software. This verification involves multiple iterative simulations to confirm the validity of the parameters and generate casting process parameters that meet the casting quality requirements. This is beneficial for reducing scrap and improving the mechanical properties of products in actual production.

[0067] When casting the base flange of the wind turbine generator set, the first-stage filtration captures large particles of slag, and the second-stage fine filtration further purifies them, generating a sand mold for the base flange of the wind turbine generator set that meets the requirements of a core-making cycle of 5 to 6 minutes. From multiple perspectives, this preparation can improve the internal purity of the casting, supporting the precision and cost reduction of the final product.

[0068] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A casting method for a base flange of a wind turbine generator set, characterized in that, At least the following steps are included: The mold used for the base flange is generated using 3D printing technology, and the mold is used to make the sand mold for casting. The mold generated by 3D printing is used to make the core of the base flange using cold core sand shooting technology. The sand is automatically discharged and gas-solid hardened by the sand shooting machine. Before casting, the process parameters of the base flange casting production process were optimized using FLOW-3D and MAGMA analysis software. The casting process employs a central pouring casting combined with a two-stage filtration casting cup. Molten iron is poured through the central pouring casting combined with the filtration device to form the base flange casting.

2. The casting method for a wind turbine generator base flange according to claim 1, characterized in that, The base flange mold includes an upper mold, a middle mold, a lower mold, and a sand core mold, and the upper mold core, middle mold core, lower mold core, and sand core are made using the corresponding molds.

3. The casting method for a wind turbine generator base flange according to claim 1, characterized in that, The 3D printed mold is made of high-strength material. The surface of the mold base is polished to form the first surface of the mold. A wear-resistant coating is applied to the first surface of the mold to generate the second surface of the mold. Microstructure textures are preset on the second surface of the mold, and regular micron-level grooves are formed by laser engraving technology to generate the third surface of the mold.

4. The casting method for a wind turbine generator base flange according to claim 1, characterized in that, Optimizing process parameters using casting process analysis software includes: simulating molten iron flow using FLOW-3D software, the simulation being used to determine pouring parameters; analyzing the sand mold solidification process using MAGMA software, the analysis being used to adjust the cold core sand ratio; optimizing the gating design based on the simulation results, the design reducing casting defects; and verifying casting quality, the verification including ultrasonic flaw detection and magnetic particle testing.

5. The casting method for a wind turbine generator base flange according to claim 1, characterized in that, The process of pouring molten iron using a center-pour casting combined with a filtration device includes: adopting a center-pour casting channel design, wherein the channel is used to guide molten iron into the sand mold; setting a two-stage filtration cup in the casting channel system, wherein the cup is used to intercept impurities in the molten iron; controlling the molten iron pouring speed, wherein the speed is determined according to the size of the sand mold; and optimizing the molten iron flow through a grouting channel, wherein the optimization improves the utilization rate of molten iron.

6. The casting method for a wind turbine generator base flange according to claim 5, characterized in that, The gating system is equipped with a two-stage filtration pouring cup, including: a primary filter screen in the pouring cup for initial interception of impurities; a secondary ceramic filter layer after the primary filter screen for further purification of molten iron; monitoring the flow state of molten iron in the pouring cup, the monitoring being used to adjust the position of the filtration device; and adjusting the filter screen aperture according to the casting size to ensure smooth flow of molten iron.

7. The casting method for a wind turbine generator base flange according to claim 1, characterized in that, First, the pre-mixed sand and binder mixture is placed into the sand storage bin of the sand shot machine. The sand shot machine uses high-pressure airflow to inject the mixture into the cavity of the mold plate. After injection, curing gas is immediately introduced to start the initial curing.

8. A casting method for a wind turbine generator base flange according to claim 1, characterized in that, The cold core sand is a pre-mixed mixture of sand and binder. The sand injection machine injects the cold core sand into the mold cavity according to the preset mold plate specifications. After injection, the gas-solid device introduces solidification gas into the mold cavity to generate a pre-solidified sand mold. The pre-cured sand mold is subjected to gas-solid hardening treatment. The gas-solid device continuously introduces curing gas, controls the gas flow rate and pressure, and generates a molding sand mold with a preset strength.

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