A wheel casting cooling system, casting apparatus and method

Abstract

This invention relates to the field of anti-gravity casting technology, specifically disclosing a wheel casting cooling system, casting equipment, and method. The system includes an upper mold cooling mechanism: annular water-cooling channels on the outer and inner sides of the inner rim, first and second upper mold water-cooling blocks located on the inner side of the intersection of the outer rim and the spokes, and annular water-cooling channels at the middle position of the spokes and the intersection position of the spokes and the wheel core; a lower mold cooling mechanism: annular air-cooling channels at the intersection position of the spokes and the outer rim, annular water-cooling channels at the middle position of the spokes and the intersection position of the spokes and the wheel core, and a lower mold spot cooling block in the thick area of ​​the wheel core; and a side mold cooling mechanism: water-cooling pipes in the area where the outer rim and the wheel rim meet above the gate, spot cooling above the gate center, and water-cooling pipes on the outer side of the wheel rim area above the gate or non-gate. This invention can control casting defects in large-size wheels while improving the mechanical properties of various areas of the wheel, significantly shortening the casting process cycle and increasing production efficiency.

Description

Technical Field

[0001] This invention relates to the field of anti-gravity casting technology, and in particular to a wheel casting cooling system, casting equipment and method. Background Technology

[0002] In recent years, with the increasing trend of lightweighting in automobiles, large-size aluminum alloy wheels have become widely used in mid-to-high-end passenger vehicles due to their unique advantages such as aesthetic appeal and lighter weight. Furthermore, with advancements in technology and materials, they are penetrating the low-to-mid-end passenger and commercial vehicle markets. However, the rapid development of the new energy vehicle industry has intensified market competition, placing higher demands on the mechanical performance and casting costs of large-size aluminum alloy wheels.

[0003] Traditional low-pressure casting processes for aluminum alloy wheels typically employ a single gating gate at the wheel core, successfully solving the problems of safe, reliable, high-volume, and low-cost production of small to medium-sized aluminum alloy wheels (14-17 inches) for passenger vehicles. However, for larger aluminum alloy wheels (18 inches and above), the sequential solidification principle required by low-pressure casting results in increasingly slower cooling rates from the rim towards the spokes and wheel core, leading to a coarser microstructure, more shrinkage cavities, and lower mechanical properties. The complex shapes and varying wall thicknesses of large wheels make it difficult to simultaneously meet casting process requirements for lightweight and low-noise designs, further exacerbating the difficulty of microstructure control. Resolving the contradiction between large-size and high-performance casting has become a bottleneck restricting industry development. Currently, the industry uses forging or forging plus casting techniques, which are costly and difficult to promote. With the rapid popularization of large-size wheels, the contradiction between high-performance and low-cost casting is becoming increasingly prominent.

[0004] In existing technologies, cooling systems are typically added to the mold to help control the solidification sequence of the casting and reduce the mold temperature, aiming to improve casting performance and production efficiency. CN101837442B discloses a low-pressure casting wheel cooling process, which uses an electromagnetic metering pump to inject water into a water-air mixed cooling channel to form water mist. The water mist cooling process is used to target different air ducts with water mist cooling or air cooling to cool the mold. The cooling medium is a mixture of water and air, which acts directly on the mold surface, allowing the mold to cool from 490℃~470℃ to 430℃~410℃ within 40~60 seconds, a temperature reduction of approximately 40~80℃. CN114247869B discloses a mold hybrid cooling structure and a low-pressure wheel hub mold having the cooling structure, including an upper mold, a lower mold, and a side mold. A water-cooling pipe is coiled inside the water-cooling cavity, and a first elastic block is fixedly connected to the water-cooling pipe and the inner wall of the water-cooling cavity. An air-cooling cavity is opened inside the side mold, and a water collection cavity is opened inside the upper mold. A carrier box is movably arranged inside the evaporation cavity, and a sponge block is arranged inside the carrier box. A vibration cavity is opened inside the upper mold, and a water removal block is arranged inside the water removal cavity. A condenser is arranged inside the second air passage. The condensate on the surface of the water-cooling pipe is detached by vibration and enters the water collection cavity. Then, it enters the carrier box in batches and is evenly absorbed by the sponge block. The gas heated by the molten aluminum evaporates and carries away the moisture inside the sponge block. At the same time, under the action of the water removal block and the condenser, the water vapor turns into dry cold air and blows it towards the water-cooling pipe to prevent the formation of condensate.

[0005] However, while the cooling methods and systems mentioned above reduce internal defects in the wheels, they also increase the casting production cycle and reduce the mechanical properties of the products, resulting in increased costs and decreased market competitiveness. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a wheel casting cooling system, casting equipment, and method. Through the design of the cooling system, combined with the multi-gate filling method of the outer rim of the casting equipment, various casting defects of the wheel can be avoided, while improving the mechanical properties of each area of ​​the wheel, shortening the casting process cycle, and increasing production efficiency.

[0007] The complete technical solution of this invention includes: A wheel casting cooling system includes an upper mold cooling mechanism, a lower mold cooling mechanism, and a side mold cooling mechanism. The upper mold cooling mechanism includes an annular water cooling channel 1 on the outer side of the inner rim, an annular water cooling channel 2 on the inner side of the inner rim, a first upper mold water cooling block 3 corresponding to the gate position and located on the inner side of the intersection of the outer rim and the spoke, a second upper mold water cooling block 4 not located at the gate position but located on the inner side of the intersection of the outer rim and the spoke, an upper mold annular water cooling channel 5 at the middle position of the spoke, and an upper mold annular water cooling channel 6 at the intersection of the spoke and the core. The lower mold cooling mechanism includes an annular air cooling channel 7 at the intersection of the spokes and the outer rim, an annular water cooling channel 8 at the middle of the spokes, an annular water cooling channel 9 at the intersection of the spokes and the core, and a cooling block 10 for the thick area of ​​the core. The side mold cooling mechanism includes: a water-cooling pipe 11 in the area where the outer rim and the wheel rim meet above the gate; a spot cooling pipe 12 above the center of the gate; a water-cooling splicing pipe 13 on the outer side of the wheel rim area above the gate; and a water-cooling pipe 14 on the outer side of the wheel rim area not above the gate. During the wheel casting process, the wheel casting cooling system cools the wheel to achieve sequential solidification in four directions, including the direction from the inner rim to the gate, the direction from the middle position of the spokes to the gate, the direction from the middle position of the spokes to the center riser, and the direction from the position without a gate on the outer rim to the position of the gate on the outer rim.

[0008] Furthermore, the heights of the first upper mold water-cooling block 3 and the second upper mold water-cooling block 4 are lower than the outer annular water-cooling channel 1 and the inner annular water-cooling channel 2 of the inner rim. The height of the annular water-cooling channel 5 at the middle position of the wheel spoke and the annular water-cooling channel 6 at the intersection of the wheel spoke and the wheel core is lower than that of the first upper mold water-cooling block 3 and the second upper mold water-cooling block 4.

[0009] Furthermore, from the inner rim to the gate direction, the following are sequentially opened: the outer annular water cooling channel 1 of the inner rim, the inner annular water cooling channel 2 of the inner rim, the water cooling splicing pipe 13 of the outer rim area above the gate, the water cooling pipe 11 of the area where the outer rim and the rim meet above the gate, and the spot cooling 12 above the center of the gate.

[0010] Furthermore, from the center of the spokes to the gate direction, firstly, the annular water cooling channel 5 of the upper mold at the center of the spokes and the annular water cooling channel 8 of the lower mold at the center of the spokes are opened simultaneously. Then, the second upper mold water cooling block 4, which is not at the gate position but is located inside the intersection of the outer rim and the spokes, the annular air cooling channel 7 of the lower mold at the intersection of the spokes and the outer rim, the first upper mold water cooling block 3, which corresponds to the gate position and is located inside the intersection of the outer rim and the spokes, and the lower mold point cooling block 10 in the thick area of ​​the wheel core are opened in sequence.

[0011] Furthermore, in the direction from the center of the spokes to the center riser, after simultaneously opening the annular water cooling channel 5 of the upper mold at the center of the spokes and the annular water cooling channel 8 of the lower mold at the center of the spokes, the annular water cooling channel 6 of the upper mold at the intersection of the spokes and the wheel core and the annular water cooling channel 9 of the lower mold at the intersection of the spokes and the wheel core are opened simultaneously.

[0012] Furthermore, in the direction from the non-gate position to the gate position on the rim, after opening the water-cooled pipe 14 on the outer side of the rim area above the non-gate, the water-cooled splicing pipe 13 on the outer side of the rim area above the gate is then opened, and finally the spot cooling 12 above the center of the gate is opened.

[0013] Furthermore, a wheel casting apparatus incorporating the aforementioned wheel casting cooling system.

[0014] Furthermore, the wheel casting equipment uses a pressure system to raise the molten metal from the riser pipe, and then enters the mold cavity through the gating structure and the gate on the mold. The gate on the mold is located on the outer rim of the wheel, and the molten metal is poured in horizontally.

[0015] Furthermore, the number of wheel spokes is not less than 5.

[0016] Furthermore, the diameter of the wheel is not less than 20 inches.

[0017] The advantages of this invention over the prior art are: 1. This invention is based on the multi-gate wheel rim process. By using mold cooling processes (spot cooling, water cooling block, circular water cooling, and cooling pipes), the solidification sequence of the traditional low-pressure casting single-gate wheel process is adjusted to four directions. This shortens the filling and solidification feeding distance of all areas of the wheel by more than half, significantly reducing the risk of the molten metal temperature being too low at the front edge during filling. It ensures that each area of ​​the wheel receives sufficient molten metal feeding during solidification, thereby avoiding related casting defects.

[0018] 2. The present invention adopts a bottom filling method, which significantly reduces the feeding distance and can appropriately reduce the casting temperature by 20°C compared with the traditional process, significantly refines the grains, and improves the mechanical performance of the wheel.

[0019] 3. This invention is based on the multi-gate wheel rim process and uses a mold cooling process to replace the local heat preservation or processing of the void structure in the traditional low-pressure casting mold for wheels, which significantly shortens the casting process cycle, improves production efficiency, and reduces manufacturing costs.

[0020] 4. The cooling scheme designed in this invention enables rapid solidification in all areas of the casting, which is beneficial for refining the microstructure of the casting and thus improving the mechanical properties of the wheel; 5. The side mold cooling method is replicated based on the number of gates. The water cooling pipes in the area where the outer rim and the wheel rim meet above the gate can be eliminated based on the mold flow analysis results. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the upper mold cooling mechanism.

[0022] Figure 2 This is a schematic diagram of the lower mold cooling mechanism.

[0023] Figure 3 This is a schematic diagram of the side mold cooling mechanism.

[0024] Figure 4 A schematic diagram of the casting structure for a wheel.

[0025] Figure 5 This is a top view of the gating system.

[0026] In the diagram: 1- Annular water-cooling channel on the outer side of the inner rim, 2- Annular water-cooling channel on the inner side of the inner rim, 3- First upper mold water-cooling block, 4- Second upper mold water-cooling block, 5- Annular water-cooling channel on the upper mold at the center of the spoke, 6- Annular water-cooling channel on the upper mold at the intersection of the spoke and the wheel core, 7- Annular air-cooling channel on the lower mold at the intersection of the spoke and the outer rim, 8- Annular water-cooling channel on the lower mold at the center of the spoke, 9- Annular water-cooling channel on the lower mold at the intersection of the spoke and the wheel core, 10- Lower mold spot cooling block in the thick area of ​​the wheel core, 11- Water-cooling pipe at the intersection of the outer rim and the wheel rim above the gate, 12- Spot cooling above the center of the gate, 13- Water-cooling splicing pipe on the outer side of the wheel rim area above the gate, 14- Water-cooling pipe on the outer side of the wheel rim area above the gate, 15- Gate, 16- First gating channel, 17- Second gating channel, 18- Third gating channel. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0028] This invention discloses a multi-gate filling cooling system for wheel casting, applicable to wheels with lightweight designs. First, the outer rim of the wheel is selected as the filling inlet, dividing the entire outer rim into two parts: the pouring position and the non-pouring position. Based on this pouring method, the solidification sequence of the traditional low-pressure casting single-gate process for wheels is adjusted to four directions: from the inner rim to the gate, from the center of the spokes to the gate, from the center of the spokes to the center riser, and from the non-gate position on the outer rim to the gate position. To achieve this, an upper mold cooling mechanism, a lower mold cooling mechanism, and a side mold cooling mechanism are designed on the mold, and the cooling channels and opening sequence of these mechanisms are designed to achieve sequential solidification of the wheel in each direction.

[0029] Specifically, such as Figure 1 As shown, the upper mold cooling mechanism includes an annular water cooling channel 1 on the outer side of the inner rim, an annular water cooling channel 2 on the inner side of the inner rim, a first upper mold water cooling block 3 corresponding to the gate position and located on the inner side of the intersection of the outer rim and the spoke, a second upper mold water cooling block 4 not located at the gate position but located on the inner side of the intersection of the outer rim and the spoke, an upper mold annular water cooling channel 5 at the middle position of the spoke, and an upper mold annular water cooling channel 6 at the intersection of the spoke and the core.

[0030] Among them, the outer annular water cooling channel 1 and the inner annular water cooling channel 2 are located at the inner rim position of the upper mold during wheel casting, and are responsible for cooling the inner rim part. The distance between the outer annular water cooling channel 1 and the wheel core is 290mm-300mm, and the distance between the inner annular water cooling channel 2 and the wheel core is 210mm-230mm.

[0031] The first upper mold water-cooling block 3 and the second upper mold water-cooling block 4 are responsible for cooling the junction of the outer rim and the spokes. Their height is lower than the outer annular water-cooling channel 1 and the inner annular water-cooling channel 2 of the inner rim. Since the wheel casting of this invention adopts a three-gate casting method, the first upper mold water-cooling block 3 and the second upper mold water-cooling block 4 cool the gate position and non-gate position of the junction of the outer rim and the spokes, respectively. The distance between the first upper mold water-cooling block 3 and the second upper mold water-cooling block 4 and the wheel core is 195mm-215mm.

[0032] The height of the annular water-cooling channel 5 at the center of the spoke and the annular water-cooling channel 6 at the intersection of the spoke and the wheel core is lower than that of the first upper mold water-cooling block 3 and the second upper mold water-cooling block 4, and is responsible for cooling the spokes. The distance between the annular water-cooling channel 5 at the center of the spoke and the wheel core is 130mm-150mm, and the distance between the annular water-cooling channel 6 at the intersection of the spoke and the wheel core is 70mm-85mm.

[0033] like Figure 2 As shown, the lower mold cooling mechanism includes a lower mold annular air cooling channel 7 at the intersection of the spokes and the outer rim, a lower mold annular water cooling channel 8 at the middle of the spokes, a lower mold annular water cooling channel 9 at the intersection of the spokes and the core, and a lower mold point cooling block 10 in the thick area of ​​the core (such as the center position, because a process riser is set at the center of the upper mold).

[0034] In this design, solidification is achieved sequentially from the outer rim of the wheel to the wheel core. Specifically, the distance between the lower mold annular air cooling channel 7 at the intersection of the spokes and the outer rim and the wheel core is 200-220mm. The distance between the lower mold annular water cooling channel 8 at the middle of the spokes and the wheel core is 160-180mm. The distance between the lower mold annular water cooling channel 9 at the intersection of the spokes and the wheel core is 90mm-110mm. The distance between the lower mold point cooling block in the thick area of ​​the wheel core and the wheel core is 50-65mm.

[0035] like Figure 3 As shown, the side mold cooling mechanism includes: a water-cooling pipe 11 at the intersection of the outer rim and the wheel rim above the gate; a spot cooling point 12 above the gate center; a water-cooling splicing pipe 13 on the outer side of the wheel rim area above the gate; and a water-cooling pipe 14 on the outer side of the wheel rim area not above the gate. This cooling mechanism achieves auxiliary cooling in each solidification direction by cooling the side mold.

[0036] This invention is based on the low-pressure casting process with multiple gates on the outer rim, and designs the solidification sequence of the wheel in four directions: from the inner rim to the gate, from the middle position of the spokes to the gate, from the middle position of the spokes to the center riser, and from the position on the outer rim without a gate to the gate.

[0037] The problem addressed in the existing technology is that traditional processes aim to achieve theoretically unidirectional sequential solidification from the inner rim to the gate to ensure feeding. However, due to the thin wall thickness of the wheel rim and the long filling distance, the temperature at the leading edge of the molten metal drops extremely rapidly when filling the thin-walled rim. To prevent premature solidification at the thin-walled area, which could lead to cold shuts or incomplete filling, the filling temperature of the molten metal must be significantly increased. However, the long-distance flow of the high-temperature molten metal results in coarse grains in the casting and a significant decrease in mechanical properties.

[0038] Furthermore, traditional single-gate processes have only one main feeding channel (from the wheel core to the wheel rim), which easily leads to isolated hot spots in areas far from the gate. Once the thin-walled section in the middle (such as the wheel rim) solidifies first, closing the channel, the distant hot spots lose their feeding source, easily resulting in concentrated shrinkage cavities and porosity defects. This invention innovatively combines mold cooling processes (point cooling, water-cooled blocks, circular water cooling, cooling pipes, etc., and coordinating the activation sequence of each cooling component) to redesign the traditional single solidification path into four directions, reducing the effective solidification and feeding distance of all areas by more than half. Areas that were originally far away are now within the coverage of the short feeding channel, fundamentally eliminating distant hot spots and avoiding the generation of concentrated shrinkage cavities and porosity defects.

[0039] Based on the above cooling system design, the activation sequence of the cooling components in each cooling mechanism in each direction is as follows: 1) From the inner rim to the gate, the cooling components and the cooling start sequence are as follows: the outer annular water cooling channel 1 of the inner rim, the inner annular water cooling channel 2 of the inner rim, the water cooling splicing pipe 13 of the outer rim area above the gate, the water cooling pipe 11 of the area where the outer rim and the rim meet above the gate, and the spot cooling 12 above the center of the gate.

[0040] The inner rim outer ring cooling (upper mold), the inner rim inner ring cooling (upper mold), the water-cooled splicing pipe on the outer side of the rim area above the gate (side mold), the water-cooled pipe in the area where the outer rim and the rim meet above the gate (side mold), and the spot cooling above the center of the gate.

[0041] 2) From the center of the spokes to the gate, the cooling components and the cooling activation sequence are as follows: First, simultaneously activate the upper mold annular water cooling channel 5 and the lower mold annular water cooling channel 8 at the center of the spokes. Then, activate the second upper mold water cooling block 4, which is not at the gate and is located inside the intersection of the outer rim and the spokes, the lower mold annular air cooling channel 7 at the intersection of the spokes and the outer rim, the first upper mold water cooling block 3, which corresponds to the gate position and is located inside the intersection of the outer rim and the spokes, and the spot cooling 12 above the gate center.

[0042] 3) From the center position of the wheel spoke to the center riser, the cooling components and the cooling opening sequence are as follows: First, open the upper mold annular water cooling channel 5 and the lower mold annular water cooling channel 8 at the center position of the wheel spoke simultaneously. Then, open the upper mold annular water cooling channel 6 and the lower mold annular water cooling channel 9 at the intersection of the wheel spoke and the wheel core simultaneously.

[0043] 4) From the position on the outer rim without a gate to the gate direction, the cooling components and the cooling start sequence are as follows: sequentially turn on the water cooling pipe 14 on the outer side of the rim area above the gate, the water cooling splicing pipe 13 on the outer side of the rim area above the gate, and the spot cooling 12 above the center of the gate.

[0044] Based on the above-described wheel casting cooling system, a multi-gate wheel casting equipment for the outer rim is described. The casting process for filling and solidifying the wheel is as follows: A low-pressure casting method is used. The low-pressure casting machine includes a holding furnace containing molten metal. The molten metal is forced upwards through a riser pipe and into the mold by the gas pressure of the pressure system. Figure 4 As shown, the riser pipe connects to the sprue cup at the top, and the sprue cup is connected to the mold cavity through the gating structure. The sprue 15 on the mold is located at the outer rim of the wheel, and the molten metal is poured horizontally. A riser is provided at the wheel core. Existing wheels use a multi-sprue design on the outer side, where the molten metal enters the cavity vertically or obliquely. Due to the abrupt change in area, the flow pattern changes abruptly, easily causing splashing, turbulence, air entrapment, and oxide inclusions. Furthermore, the local flow velocity is too high, and the temperature field is uneven, easily causing local structural abnormalities and cold shuts. To address the above problems, this invention creatively uses a gating channel to change the molten metal from vertical to horizontal flow into the outer rim. This channel connects the sprue and the outer rim cavity. The molten metal rises vertically in the sprue, and after entering the horizontal gating channel, the flow direction changes from vertical to horizontal, entering the cavity along the outer rim in a horizontal laminar flow state. It achieves smooth, uniform, and synchronous liquid feeding along the outer rim circumferential direction, which not only increases the liquid feeding area but also reduces the metal liquid velocity and makes the filling process more stable. It effectively avoids direct liquid flow, turbulence, air entrapment, and oxidation inclusions, greatly improving the filling stability and solving the problem of secondary oxidation inclusions caused by air entrapment during the filling process.

[0045] Secondly, since the wheel to be formed in this invention has a five-spoke structure, and the five-spoke wheel has an asymmetrical structure with an included angle of 72° between each spoke, the casting process of wheels usually adopts a symmetrical type (2, 3, 4 pouring channels, etc.). For the asymmetrical five-spoke wheel, when using symmetrical multi-channel filling, the pouring time of different spokes will be different, which will easily cause the filling time of each spoke to be inconsistent, resulting in problems such as air entrapment and uncontrollable solidification sequence, which can easily lead to casting defects. Therefore, when casting a five-spoke wheel, the gating system structure of the wheel is designed to avoid the above problems.

[0046] Based on the above considerations, this invention has made targeted designs for the wheel structure and casting structure, such as... Figure 5 As shown, the casting structure includes two types of casting channels: a first casting channel 16, a second casting channel 17, and a third casting channel 18. The second and third casting channels 17 and 18 have identical structures and are responsible for filling and casting the gates of two spokes, respectively. The first casting channel 16 is responsible for filling and casting the gate of one spoke. The angle between the lines connecting the three casting channels and the wheel center is 120°.

[0047] Furthermore, because this invention employs a different method from existing technologies—utilizing a casting channel for horizontal pouring—the two casting channels have different numbers of spokes, significantly different flow areas, and different arc lengths, resulting in noticeable differences in flow behavior. Secondly, the molten metal flow field is highly sensitive to channel cross-sectional characteristics and process parameters. Cross-sections with abrupt area changes or high irregularity can lead to turbulent flow and air entrapment, and mismatches between filling speed and pressure can cause uneven filling.

[0048] Based on the above issues, it is necessary to design the relevant dimensional parameters of the pouring channels for both structures to ensure smooth and rapid mold filling, avoid air entrapment, turbulence, and casting defects, and minimize the amount of molten metal used. Specifically: First, define the design parameters for the gating system, including: 1) Effective flow area : refers to the cross-sectional area of ​​the upper surface of the pouring channel; 2) Profile feature value W: is the ratio of the perimeter of the profile of the upper surface of the pouring channel to the perimeter of a circle with the same area as the pouring channel.

[0049] The following constraints are adopted:

[0050] In the formula, The effective flow area of ​​the second pouring channel. This represents the effective flow area of ​​the first pouring channel.

[0051]

[0052] In the formula, The profile feature value of the second pouring channel. The contour feature value of the first pouring channel.

[0053] and:

[0054] In the above formula, the effective flow area profile feature values ​​of the second and third pouring channels are the same.

[0055] In determining the above indicators, the five-spoke wheel casting system of this invention adopts a distribution method of 1 single-spoke channel + 2 double-spoke channels. The effective flow area directly determines the flow capacity and is the core of flow matching; the profile feature value determines the regularity of the cross-section and is the core of controlling flow resistance and eddies. The two indicators work together to limit the effective flow area ratio, reduce the time difference of the molten metal reaching the spokes, and avoid the problem of some spokes being filled too quickly and others too slowly. Through the constraint of the profile feature value, the liquid flow separation and eddies caused by rapidly expanding cross-sections and highly irregular cross-sections are avoided, allowing the molten metal to maintain a laminar / weakly turbulent state in the channel, greatly reducing the probability of the cavity gas being trapped, and achieving a balance between quality, efficiency and cost.

[0056] Based on the above principles and after practical verification, the cross-sectional structures of the first pouring channel 16, the second pouring channel 17, and the second pouring channel 17 are as follows: Figure 5 As shown, the first pouring channel includes a first initial pouring area in the center and first outer rim pouring areas on both sides. The second and third pouring channels each include a second initial pouring area in the center, a transition area, and second outer rim pouring areas on both sides.

[0057] The length of the arc between the starting and ending points of the first gating channel and concentric with the outer rim is defined as the arc length of the first gating channel. The length of the arc between the starting and ending points of the second gating channel and concentric with the outer rim is defined as the arc length of the second gating channel, such that the arc length of the first gating channel : the arc length of the second gating channel = 0.45~0.5. The effective flow area of ​​the first gating channel is approximately 323.9 cm². 2 The effective flow area of ​​the second pouring channel is approximately 588.7 cm². 2 .

[0058] Verification has shown that the above design allows for a larger feed area at each spoke and closer filling distances at the set filling speed. The overall filling speed is lower, not exceeding 0.5 m / s, with no turbulence or air entrapment, resulting in smoother bottom-up filling. Furthermore, the short filling process, with the areas of prolonged metal-air contact primarily located at the inner rim and center riser, effectively eliminates heat spots at the spoke-rim junction. The temperature at the metal front during filling is not lower than 616℃, eliminating the risk of incomplete pouring.

[0059] The method for wheel forming using the above-mentioned device includes stages of liquid lifting, mold filling, crystallization pressurization and holding, and pressure release and venting. Here, the molten metal used is molten aluminum, and the specific steps are as follows: (1) Liquid rise: The aluminum liquid in the holding furnace is pressurized by a high-pressure gas source, so that the aluminum liquid rises along the liquid riser pipe to a position about 100mm below the gate. The pressurization rate at this stage is 13mbar / s-18mbar / s, and the pressure is increased to 115mbar-125mbar.

[0060] (2) Filling the mold: Continue to increase the pressure. The liquid rising rate at this stage is 3mbar / s-6mbar / s. Increase the pressure to 215mbar-235mbar so that the aluminum liquid fills the mold cavity.

[0061] (3) Shell formation: After the filling is completed, the pressure is increased to 225mbar-245mbar at a pressurization rate of 2mbar / s-4mbar / s.

[0062] (4) Extrusion, pressurization, and pressure holding: ① After the shelling process is completed, the pressure is rapidly increased to 800 mbar at a pressurization rate of 30 mbar / s - 60 mbar / s, and the pressure is held for 100 s - 120 s. At this time, the wheel solidification is completed; ② When the timer reaches 50-70 s after the filling is completed, the extrusion cylinder is started, and the extrusion pin connected to it is driven to move downward from the initial position by 40 mm - 50 mm at a speed of 2 mm / s - 5 mm / s (the initial position and stroke of extrusion vary depending on the center structure of the wheel) and is held in this position for 40 s - 70 s. Then, under the drive of the extrusion cylinder, the extrusion pin is withdrawn to the initial position, that is, separated from the extruded wheel, so as to avoid affecting the normal demolding of the product.

[0063] (5) Pressure relief and venting: After the pressure holding stage is completed, that is, the aluminum alloy wheel is solidified, the gas pressure in the heat preservation furnace is released, so that the unsolidified aluminum liquid in the riser pipe and the gate flows back into the heat preservation furnace. Then, the wheel is kept in the mold for 70s-100s before the mold is opened and the part is removed.

[0064] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A wheel casting cooling system, characterized in that, Includes upper mold cooling mechanism, lower mold cooling mechanism, and side mold cooling mechanism. The upper mold cooling mechanism includes an annular water cooling channel (1) on the outer side of the inner rim, an annular water cooling channel (2) on the inner side of the inner rim, a first upper mold water cooling block (3) corresponding to the gate position and located on the inner side of the intersection of the outer rim and the spoke, a second upper mold water cooling block (4) not located at the gate position and located on the inner side of the intersection of the outer rim and the spoke, an upper mold annular water cooling channel (5) at the middle position of the spoke, and an upper mold annular water cooling channel (6) at the intersection of the spoke and the core. The lower mold cooling mechanism includes an annular air cooling channel (7) at the intersection of the spokes and the outer rim, an annular water cooling channel (8) at the middle of the spokes, an annular water cooling channel (9) at the intersection of the spokes and the core, and a cooling block (10) in the thick area of ​​the core. The side mold cooling mechanism includes: a water-cooling pipe (11) in the area where the outer rim and the wheel rim meet above the gate, a spot cooling pipe (12) above the center of the gate, a water-cooling splicing pipe (13) on the outer side of the wheel rim area above the gate, and a water-cooling pipe (14) on the outer side of the wheel rim area not above the gate. During the wheel casting process, the wheel casting cooling system cools the wheel to achieve sequential solidification in four directions, including the direction from the inner rim to the gate, the direction from the middle position of the spokes to the gate, the direction from the middle position of the spokes to the center riser, and the direction from the position without a gate on the outer rim to the position of the gate on the outer rim.

2. The wheel casting cooling system according to claim 1, characterized in that, The height of the first upper mold water cooling block (3) and the second upper mold water cooling block (4) is lower than the outer annular water cooling channel (1) and the inner annular water cooling channel (2) of the inner wheel rim. The height of the annular water cooling channel (5) at the middle position of the wheel spoke and the annular water cooling channel (6) at the intersection of the wheel spoke and the wheel core is lower than that of the first upper mold water cooling block (3) and the second upper mold water cooling block (4).

3. The wheel casting cooling system according to claim 2, characterized in that, From the inner rim to the gate direction, sequentially open the outer annular water cooling channel (1), the inner annular water cooling channel (2), the outer water cooling splicing pipe (13) of the rim area above the gate, the water cooling pipe (11) of the area where the outer rim and the rim meet above the gate, and the spot cooling (12) above the center of the gate.

4. A wheel casting cooling system according to claim 3, characterized in that, From the center of the spokes to the gate direction, firstly, open the annular water cooling channel (5) of the upper mold at the center of the spokes and the annular water cooling channel (8) of the lower mold at the center of the spokes simultaneously. Then, open the second upper mold water cooling block (4) which is not at the gate position and is located inside the intersection of the outer wheel rim and the spokes in sequence, the annular air cooling channel (7) of the lower mold at the intersection of the spokes and the outer wheel rim, the first upper mold water cooling block (3) which corresponds to the gate position and is located inside the intersection of the outer wheel rim and the spokes, and the lower mold point cooling block (10) in the thick area of ​​the wheel core.

5. A wheel casting cooling system according to claim 4, characterized in that, From the center position of the wheel spoke to the center riser, after simultaneously opening the annular water cooling channel (5) of the upper mold at the center position of the wheel spoke and the annular water cooling channel (8) of the lower mold at the center position of the wheel spoke, then simultaneously opening the annular water cooling channel (6) of the upper mold at the intersection of the wheel spoke and the wheel core and the annular water cooling channel (9) of the lower mold at the intersection of the wheel spoke and the wheel core.

6. A wheel casting cooling system according to claim 5, characterized in that, From the rim without a gate to the rim with a gate, after opening the water-cooled pipe (14) on the outer side of the rim area above the gate, open the water-cooled splicing pipe (13) on the outer side of the rim area above the gate, and finally open the spot cooling (12) above the center of the gate.

7. A wheel casting apparatus having the wheel casting cooling system according to any one of claims 1-6.

8. A wheel casting equipment according to claim 7, characterized in that, The wheel casting equipment uses a pressure system to make molten metal rise from the riser pipe and enter the mold cavity through the gating structure and the gate on the mold. The gate on the mold is opened on the outer rim of the wheel, and the molten metal is poured in horizontally.

9. A wheel casting equipment according to claim 8, characterized in that, The number of spokes on the wheel shall not be less than 5.

10. A method for casting wheels using the wheel casting equipment of claim 8, characterized in that, The diameter of the wheel is not less than 20 inches.

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