Engine casting method

Abstract

The invention provides an engine casting method, which relates to the technical field of engine casting, and comprises the following steps: step 1, selecting and proportioning raw materials; 2, smelting the raw materials to prepare molten metal; 3, molten metal treatment; and fourthly, molten metal is poured and cooled, molten metal treatment comprises additive manufacturing and molten metal and additive mixing, and raw materials of the additive comprise pigskin and salt. According to the method, pigskin and salt are added during casting of the engine, and the specific operation comprises the steps that the pigskin and the salt are placed in a pot, water is added for slow cooking, the pigskin and the salt are dissolved, the dissolved mixed liquid is poured into molten metal, water is evaporated, and the problems that the engine is overheated, oil is wasted and power is insufficient are solved.

Description

Technical Field

[0001] This invention belongs to the field of engine casting technology, and particularly relates to an engine casting method. Background Technology

[0002] An engine is a machine that converts other forms of energy into mechanical energy, including internal combustion engines (reciprocating piston engines), external combustion engines (Stirling engines, steam engines, etc.), jet engines, and electric motors. Internal combustion engines, for example, typically convert chemical energy into mechanical energy. The term "engine" can refer to both the power-generating device and the entire machine including the power unit (e.g., gasoline engines, aircraft engines). The engine originated in Britain, and its original meaning refers to a "mechanical device that generates power." Engine casting is a crucial step in the manufacturing of core components (such as cylinder blocks, cylinder heads, crankshafts, and pistons) in the automotive, aerospace, and other fields. Castings must meet stringent requirements such as high strength, high temperature resistance, good sealing, and high dimensional accuracy. Different engine components require specific casting processes due to differences in materials (cast iron, aluminum alloys, etc.) and structures.

[0003] Modern engines are prone to overheating during operation, and the engine temperature is difficult to lower. Overheating can lead to insufficient engine power, increased fuel consumption, and reduced operating costs and engine efficiency. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes an engine casting method to more accurately resolve the problems described above.

[0005] This invention is achieved through the following technical solution: This invention proposes an engine casting method, comprising the following steps: Step 1: raw material selection and proportioning; Step 2: raw material smelting to produce molten metal; Step 3: molten metal treatment; Step 4: molten metal pouring and cooling, wherein molten metal treatment includes additive preparation and mixing of molten metal and additives, and the additive raw materials include pigskin and salt.

[0006] In one example, the additive is prepared by placing pig skin and salt in a pot, adding water and simmering until the pig skin and salt dissolve. The method for mixing the molten metal and the additive is to pour the dissolved mixture into the molten metal and allow the water to evaporate.

[0007] In one example, the raw materials selected and proportioned include main materials, recycled materials, and alloy additives. The main materials include alloy ingots and pure aluminum ingots. The standard composition of the alloy ingots includes Si 9.6-12.0%, Cu 1.5-3.5%, Mg 0.3-0.5%, and Fe ≤1.3%. The aluminum content in the pure aluminum ingots is ≥99.5%. The recycled materials are broken old castings. The alloy additives include silicon ingots, copper ingots, and magnesium ingots with a purity of ≥99%.

[0008] In one example, the raw material smelting process for producing molten metal includes charging, melting, refining and degassing, modification treatment, temperature adjustment, and composition detection. The charging sequence is as follows: pure aluminum ingots are placed at the bottom, alloy ingots and recycled materials are placed in the middle layer, and silicon ingots, copper ingots, and magnesium ingots are placed at the top layer. After charging, melting is carried out. The initial melting temperature is 400-500℃, which is then increased to 650℃ for stirring. Finally, the temperature is increased to 720℃, and all the metal is liquefied. Refining and degassing uses Al-Sr master alloy and aluminum fluoride refining agent. When adding the refining agent, it is directly injected into the molten aluminum in two batches while stirring, and argon gas is simultaneously introduced. The final temperature is adjusted to between 650-750℃. Composition detection uses a spectrometer to detect the content of Si, Cu, Mg, and Fe in real time.

[0009] In one example, the alloy ingots and recycled materials are alternately layered, with silicon ingots, copper ingots, and magnesium ingots added in multiple batches.

[0010] In one example, the molten metal pouring and cooling includes temperature detection, mold and gating system inspection, pouring operation, and cooling management. Temperature detection is performed by measuring the temperature of the molten aluminum using an infrared thermometer to ensure it is within the process requirements. Mold and gating system inspection includes mold temperature adjustment and gating system inspection. The pouring operation involves pouring the molten aluminum into the mold for shaping. Cooling management uses forced air cooling for cooling and shaping.

[0011] In one example, the casting operation uses a vacuum pipeline to transport the molten metal.

[0012] In one example, the recycled material is classified using spectral rapid sorting technology and degreasing is performed using high-temperature pyrolysis and inert gas protection.

[0013] The engine casting method proposed in this invention can bring the following beneficial effects: Firstly, pigskin and salt are added during engine casting. Specifically, the pigskin and salt are placed in a pot, water is added and simmered to dissolve them. The dissolved mixture is then poured into the molten metal. After the water evaporates, the problems of engine overheating, excessive fuel consumption, and insufficient power are solved. Secondly, alloy ingots and recycled materials are alternately layered and filled. Silicon ingots, copper ingots, and magnesium ingots are added multiple times. When alloy ingots and recycled materials are alternately layered and filled, materials of different densities will naturally roll and mix due to gravity during the melting process. This makes it easier to achieve uniform composition than simply stacking, which can accelerate heat transfer, shorten melting time, and reduce energy consumption. Adding silicon / copper ingots in small batches can shorten the single melting time. Due to the small difference in melting point, they can be easily dissolved quickly, improving the overall smelting efficiency, reducing the amount of instantaneous gas generated, and avoiding excessive gas absorption by the molten aluminum.

[0014] Thirdly, by using vacuum pipelines to transport molten metal, the gas content of the molten metal can be reduced by more than 80%, and the porosity defect rate of the casting can be reduced to below 0.1%. This is especially effective for easily oxidized materials such as aluminum alloys and magnesium alloys. The molten metal has better fluidity and can fill the mold cavity more evenly, especially the corners of complex thin-walled structures, which are filled more fully. This reduces shrinkage cavities caused by the molten metal not reaching the mold, isolates oxygen, and can reduce the loss of easily burned elements such as aluminum, magnesium, and chromium, ensuring the stability of the casting composition and thus ensuring that the mechanical properties meet the standards. Attached Figure Description

[0015] The accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, are illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention.

[0016] In the attached diagram: Figure 1 This is a schematic diagram of the process of the present invention. Detailed Implementation

[0017] To more clearly illustrate the overall concept of the present invention, a detailed description will be provided below with reference to the accompanying drawings and examples.

[0018] like Figure 1 As shown, an embodiment of the present invention proposes an engine casting method, including the following steps: Step 1: raw material selection and proportioning; Step 2: raw material smelting to produce molten metal; Step 3: molten metal treatment; Step 4: molten metal pouring and cooling, wherein molten metal treatment includes additive preparation and mixing of molten metal and additives, and the additive raw materials include pigskin and salt.

[0019] like Figure 1 As shown, the additive is made by placing pig skin and salt in a pot, adding water and simmering slowly to dissolve the pig skin and salt, forming a mixed solution. Before the molten metal is poured out of the furnace, the mixed solution is mixed with the molten metal. The method of mixing the molten metal and the additive is to pour the dissolved mixed liquid into the molten metal. After the water evaporates, the additive is ready. This solves the problems of engine overheating, excessive fuel consumption and insufficient power.

[0020] like Figure 1As shown, the raw materials selected and proportioned include main materials, recycled materials, and alloy additives. The main materials include alloy ingots and pure aluminum ingots. The standard composition of alloy ingots includes Si 9.6-12.0%, Cu 1.5-3.5%, Mg 0.3-0.5%, and Fe ≤1.3%. The aluminum content in pure aluminum ingots is ≥99.5%. The recycled materials are broken old castings. The alloy additives include silicon ingots, copper ingots, and magnesium ingots with a purity of ≥99%.

[0021] like Figure 1 As shown, the process of smelting raw materials to produce molten metal includes charging, melting, refining and degassing, modification treatment, temperature adjustment, and composition testing. The charging sequence is as follows: pure aluminum ingots at the bottom, alloy ingots and recycled materials in the middle, and silicon, copper, and magnesium ingots at the top. After charging, melting is carried out. The initial melting temperature is 400-500℃, and the temperature is slowly heated to avoid oxidation of the aluminum ingots. Then, the temperature is increased to 650℃ and stirred. Finally, the temperature is increased to 720℃, and all the metal is liquefied. Refining and degassing uses Al-Sr intermediate alloy and aluminum fluoride refining agent to reduce HF gas emissions. When adding the refining agent, it is directly injected into the molten aluminum in two batches while stirring, and argon gas is injected simultaneously. Nanoscale inert gas carriers (such as argon microbubble generators) can be added to improve bubble dispersion and increase degassing efficiency by 30%. After refining, the mixture is allowed to stand to remove surface slag. The final temperature is adjusted to between 650-750℃. The specific temperature is adjusted according to the casting wall thickness. Thin-walled parts (<3mm): take the upper limit of 750℃; For thick-walled parts (>10mm): take the lower limit of 650℃; The composition analysis uses a spectrometer to detect the content of Si, Cu, Mg, and Fe in real time. If the Si content is insufficient, an aluminum-silicon master alloy (such as Al-50Si, the amount to be added is calculated based on the detected value) is added. If the Cu content is too low, pure copper sheets are added, which need to be broken into small pieces to avoid floating on the surface. If the Mg content is insufficient due to burn-off, pure magnesium ingots are added, cut into small pieces, wrapped in aluminum foil, and then immersed in molten aluminum to reduce oxidation. If a certain element exceeds the standard, such as Fe being too high, virgin aluminum ingots need to be added for dilution. The amount to be added is calculated according to the ratio, and the mixture is stirred again and tested again until the composition is qualified.

[0022] like Figure 1 As shown, alloy ingots and recycled materials are alternately layered and filled. Silicon ingots, copper ingots, and magnesium ingots are added in multiple batches. When alloy ingots and recycled materials are alternately layered and filled, materials of different densities will naturally roll and mix due to gravity during the melting process. This makes it easier to achieve uniform composition than simply stacking, which can accelerate heat transfer, shorten melting time, and reduce energy consumption. Adding silicon / copper ingots in small batches can shorten the single melting time. Due to the small difference in melting point, they can be easily dissolved quickly, improving the overall smelting efficiency, reducing the amount of instantaneous gas generated, and avoiding excessive gas absorption by the molten aluminum.

[0023] like Figure 1As shown, the metal pouring and cooling process includes temperature monitoring, mold and gating system inspection, pouring operation, and cooling management. Temperature monitoring involves using an infrared thermometer to measure the temperature of the molten aluminum to ensure it is within the required process range. The pouring temperature is typically 650-750°C, adjusted according to the casting wall thickness. Mold and gating system inspection includes mold temperature adjustment, preheating the metal mold to 180-250°C, and gating system inspection, checking the gate, sprue, and runner for unobstructed flow and no blockages or deformation. A split-type metal mold is used, consisting of a fixed mold and a moving mold. The mold cavity surface is coated with a ceramic coating (0.1-0.3mm thick). The ceramic coating contains nano-sized zirconia particles (50-100nm in diameter) to improve the mold's wear resistance and heat insulation. A spiral water-cooling channel is installed inside the mold, 15-20mm away from the cavity surface. The cooling water flow rate in different areas is controlled by a flow control valve. The casting process involves pouring molten aluminum into the mold for shaping. The molten metal is preheated to 200-300℃ through a pressure chamber and injected into the mold cavity at high pressure (80-120MPa) and high speed (30-50m / s). The filling time is extremely short (0.1-0.3 seconds) to ensure the complex structure is completely filled. After filling, the pressure is maintained at (30-50MPa) for 5-10 seconds. The process involves several seconds to promote molten metal shrinkage and reduce shrinkage cavities. Forced air cooling is used for cooling and molding. After molding, the mold is opened, and the casting is ejected via an ejector mechanism. Defects such as flash and cracks are checked. Flash on the parting surface is removed by robot or manual labor. Residual mold release agent in the cavity is cleaned with a high-pressure water gun. The casting is held at 520℃ for 2 hours, then water-quenched and aged at 120℃ for 4 hours to increase strength (tensile strength ≥ 250MPa). Before formal pouring, a small test block (e.g., 50-100g) can be poured to observe its surface smoothness, absence of pores or cold shuts. Formal pouring proceeds only after confirming the process is normal. Initially, pouring is slow to fill the gate and sprue to prevent aluminum splashing. In the middle stage, pouring is rapid until the cavity is full to reduce oxidation time. Finally, pouring is slow to fill the riser and thin-walled areas to prevent shrinkage porosity. The pouring time is adjusted according to the thickness of the casting. Thin-walled parts (<3mm): Pouring time ≤5 seconds; Thick-walled parts (>10mm): Pouring time ≥10 seconds; After pouring is completed, immediately pour the remaining molten aluminum in the ladle into a designated recycling container to avoid waste due to cooling.

[0024] like Figure 1As shown, the casting operation uses a vacuum pipeline to transport the molten metal, avoiding secondary oxidation and gas absorption caused by contact between the molten metal and air. Vacuum pipeline transportation can reduce the gas content of the molten metal by more than 80%, and reduce the porosity defect rate of the casting to below 0.1%. It is particularly effective for easily oxidized materials such as aluminum alloys and magnesium alloys. The molten metal has better fluidity and viscosity is reduced by 10-15%, which can fill the mold cavity more evenly, especially the corners of complex thin-walled structures. It can also reduce shrinkage cavities caused by the molten metal not reaching the mold, and isolate oxygen, which can reduce the loss of easily burned elements such as aluminum, magnesium, and chromium, and ensure the stability of the casting composition, thereby ensuring that the mechanical properties meet the standards.

[0025] like Figure 1 As shown, the recycled materials are classified using rapid spectral sorting technology. Spectroscopic techniques, such as X-ray fluorescence spectroscopy / XRF or laser-induced breakdown spectroscopy / LIBS, can quickly analyze the content of elements such as Al, Si, Cu, Fe, and Mg in the recycled materials with an error of <0.5%, avoiding misjudgment of composition due to manual sorting. It can identify and separate non-aluminum impurities such as bolts and bearings, including steel and copper alloys, to avoid the formation of brittle intermetallic compounds during smelting. High-temperature pyrolysis and inert gas protection are used for degreasing treatment, reducing wastewater discharge and avoiding increased hydrogen content caused by residual alkali.

[0026] Working principle: Pure aluminum ingots are arranged at the bottom, alloy ingots and recycled materials in the middle layer, and silicon, copper, and magnesium ingots are arranged at the top layer. After loading, the materials are melted. The initial melting temperature is 400-500℃, and the temperature is slowly heated to avoid oxidation of the aluminum ingots. Then, the temperature is increased to 650℃ and stirred. Finally, the temperature is increased to 720℃, and all the metals are liquefied. Al-Sr master alloy and aluminum fluoride refining agent are added for refining and degassing. When adding the refining agent, it is directly injected into the aluminum liquid in two batches while stirring, and argon gas is simultaneously introduced. Nanoscale inert gas carriers (such as argon microbubble generators) can be added to improve bubble dispersion and increase degassing efficiency by 30%. After refining, the mixture is allowed to stand to remove surface impurities. Remove scum, adjust the temperature to a final range of 650-750℃, pour out the molten metal, place pigskin and salt in a pot, add water and simmer until the pigskin and salt dissolve. Mix the molten metal with the additives by pouring the dissolved mixture into the molten metal; allow the water to evaporate. Preheat the metal mold to 180-250°C, check the gate, sprue, and runner for blockages or deformation. Pour the molten aluminum into the mold to form the shape. The molten metal is injected into the mold cavity through the pressure chamber (preheated to 200-300℃) at high pressure (80-120MPa) and high speed (30-50m / s), with a very short filling time (0.1-0.3 seconds). (Seconds), ensuring the complex structure is fully filled. After filling, maintain pressure (30-50MPa) for 5-10 seconds to promote metal shrinkage and reduce shrinkage cavities. Cooling management uses forced air cooling for cooling and molding. After molding, open the mold and eject the casting through the ejector mechanism. Check for defects such as flash and cracks. Remove flash from the parting surface using a robot or manually. Clean the cavity with a high-pressure water gun to remove residual mold release agent. Hold at 520℃ for 2 hours, water quench, and age at 120℃ for 4 hours to improve strength.

[0027] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0028] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. An engine casting method, characterized in that, The process includes the following steps: Step 1: Raw material selection and proportioning; Step 2: Raw material smelting to produce molten metal; Step 3: Molten metal treatment; Step 4: Molten metal pouring and cooling. Molten metal treatment includes additive preparation and mixing of molten metal and additives. The additive raw materials include pigskin and salt.

2. The engine casting method according to claim 1, characterized in that, The additive is prepared by placing pig skin and salt in a pot, adding water and simmering until the pig skin and salt dissolve. The additive is mixed with the molten metal by pouring the dissolved mixture into the molten metal and allowing the water to evaporate.

3. The engine casting method according to claim 1, characterized in that, The raw materials selected and proportioned include main materials, recycled materials, and alloy additives. The main materials include alloy ingots and pure aluminum ingots. The standard composition of the alloy ingots includes Si 9.6-12.0%, Cu 1.5-3.5%, Mg 0.3-0.5%, and Fe ≤1.3%. The aluminum content in the pure aluminum ingots is ≥99.5%. The recycled materials are broken old castings. The alloy additives include silicon ingots, copper ingots, and magnesium ingots with a purity of ≥99%.

4. The engine casting method according to claim 3, characterized in that, The process of smelting raw materials to produce molten metal includes charging, melting, refining and degassing, modification treatment, temperature adjustment, and composition detection. The charging sequence is as follows: pure aluminum ingots are placed at the bottom, alloy ingots and recycled materials are placed in the middle layer, and silicon ingots, copper ingots, and magnesium ingots are placed at the top layer. After charging, melting is carried out. The initial melting temperature is 400-500℃, which is then increased to 650℃ for stirring. Finally, the temperature is increased to 720℃, and all metals are liquefied. Refining and degassing are carried out using Al-Sr master alloy and aluminum fluoride refining agent. When adding the refining agent, it is directly injected into the molten aluminum in two batches while stirring, and argon gas is simultaneously introduced. The final temperature is adjusted to between 650-750℃. The composition detection uses a spectrometer to detect the content of Si, Cu, Mg, and Fe in real time.

5. The engine casting method according to claim 4, characterized in that, The alloy ingots and recycled materials are alternately layered and loaded, with silicon ingots, copper ingots and magnesium ingots added in multiple batches.

6. The engine casting method according to claim 1, characterized in that, The metal molten casting and cooling process includes temperature detection, mold and gating system inspection, casting operation, and cooling management. Temperature detection is performed by measuring the temperature of the aluminum molten metal with an infrared thermometer to ensure that it is within the process requirements. Mold and gating system inspection includes mold temperature adjustment and gating system inspection. Casting operation involves pouring the aluminum molten metal into the mold for shaping. Cooling management uses forced air cooling to reduce the temperature and shape the molten metal.

7. The engine casting method according to claim 6, characterized in that, The casting operation uses a vacuum pipeline to transport the molten metal.

8. The engine casting method according to claim 1, characterized in that, The recycled material is classified using spectral rapid sorting technology and degreased using high-temperature pyrolysis and inert gas protection.

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