Gravity gap gradual change type aluminum alloy hub pouring system

Abstract

The invention relates to a gravity gap gradual change type aluminum alloy hub pouring system, and belongs to the technical field of hub casting, the gravity gap gradual change type aluminum alloy hub pouring system is arranged on a side die and comprises a pouring port and a runner, the pouring port is communicated with the runner, the outlet end of the runner is communicated with a hub cavity, the runner comprises a plurality of flow dividing gap sections which are sequentially connected in the aluminum liquid flowing direction, and the flow dividing gap sections are communicated with the runner. The sectional area of each flow dividing gap section is gradually decreased in the flowing direction of the molten aluminum, a flow speed regulation and control node is formed between every two adjacent flow dividing gap sections through the change of the sectional area, and a transition flow guide face is arranged at each flow speed regulation and control node. When the change rate of the start-end sectional area of the upstream shunting gap section is greater than that of the downstream shunting gap section, the transition flow guide surface is arranged in a concave arc shape; and when the change rate of the start-end sectional area of the upstream shunting gap section is smaller than that of the downstream shunting gap section, the transition flow guide surface is arranged in a convex arc shape. Through gradient velocity adjustment of the multiple flow dividing gap sections, the flow velocity of molten aluminum is convenient to adjust and control, then turbulent flow and oxide inclusions are reduced, and mold filling uniformity can be improved.

Description

Technical Field

[0001] The present application relates to the field of wheel hub casting, and in particular to a gravity gap gradient aluminum alloy wheel hub casting system. Background Art

[0002] Aluminum alloy wheels have become an important choice in the automotive industry to replace traditional steel wheels due to their light weight, high specific strength and excellent heat dissipation performance. In the field of manufacturing technology, gravity casting is still widely used in the production of mid- and low-end wheels due to its low equipment investment and strong process adaptability. However, this process has significant defects in the pouring process: the traditional pouring system usually adopts a straight-through flow channel design with a single cross-section. When the aluminum liquid is quickly filled under the action of gravity, turbulence is easily formed in the flow channel, causing gas to be drawn into the cavity, resulting in defects such as pores and oxidation inclusions in the casting. In addition, due to the lack of flow rate control of the aluminum liquid during the flow process, the temperature difference between the front metal liquid and the end metal liquid is too large, which is prone to cold shut or incomplete filling, seriously affecting the density and mechanical properties of the wheel.

[0003] A Chinese patent with publication number CN202447589U discloses a molten metal pouring device for an automobile wheel hub casting mold, which improves the smoothness of the molten metal flow by adding a liquid storage chamber and an exhaust structure. However, this type of improvement only focuses on local gas discharge, and fails to fundamentally optimize the control of the flow state of the aluminum liquid by the flow channel structure. In traditional flow channel design, the cross-sectional area is mostly designed with linear reduction or step-type mutation. Although this method can partially adjust the flow rate, the aluminum liquid will still produce a sudden drop in flow rate or secondary eddy currents when flowing through the cross-sectional area mutation area, resulting in uncontrolled temperature gradient at the front of the metal liquid, exacerbating the risk of air entrainment and cold shut. Especially for the complex structure of the wheel hub cavity, the matching degree between the flow channel cross-sectional area and the flow rate is insufficient, resulting in uneven kinetic energy loss during the aluminum liquid filling process, making it difficult to achieve laminar filling, and ultimately leading to problems such as coarse grains inside the wheel hub and discrete mechanical properties. Summary of the invention

[0004] In order to facilitate the regulation of the flow rate of molten aluminum, reduce turbulence and oxidation inclusions, and improve filling uniformity, the present application provides a gravity gap gradient aluminum alloy wheel casting system.

[0005] The present application provides a gravity gap gradient aluminum alloy wheel casting system, which adopts the following technical solutions: A gravity gap gradient aluminum alloy wheel casting system is provided on a side mold, comprising a pouring port and a runner, wherein the pouring port is connected to the runner, and the outlet end of the runner is connected to the wheel hub cavity, wherein the runner comprises a plurality of flow diversion gap sections connected in sequence along the flow direction of the aluminum liquid, wherein the cross-sectional area of ​​each of the flow diversion gap sections is arranged to decrease along the flow direction of the aluminum liquid, and a flow rate control node is formed between adjacent flow diversion gap sections by changing the cross-sectional area, and a transition guide surface is provided at the flow rate control node; When the change rate of the cross-sectional area at the beginning and end of the upstream diversion gap section is greater than that at the downstream, the transition guide surface is set in an inwardly concave arc shape; When the rate of change of the cross-sectional area at the beginning and end of the upstream diversion gap section is smaller than that at the downstream, the transition guide surface is arranged in an outwardly convex arc shape.

[0006] By adopting the above technical scheme, the present application forms a gradient speed control in the process of aluminum liquid flow through the design of decreasing cross-sectional area of ​​multiple diverter gap sections in the flow channel, which promotes the gradual change of flow resistance. The setting of the flow rate control node optimizes the kinetic energy distribution of aluminum liquid, reduces the turbulence and oxidation inclusions caused by the sudden change of flow rate, and improves the filling uniformity. The front end of the aluminum liquid enters the hub cavity at a more stable speed, reduces the loosening of the metal structure caused by pressure fluctuations in the rim area, and improves the overall density of the casting. At the same time, according to the difference in the change rate of the cross-sectional area of ​​different diverter gap sections, the transition guide surface adopts an inner concave or outer convex arc to adapt to the flow rate change trend. When it is set in an inner concave arc, the flow channel contour is contracted in the area where the cross-sectional area suddenly decreases, accelerating the aluminum liquid to pass through the node and avoiding local retention; when it is set in an outer convex arc, the flow channel is expanded in the area where the cross-sectional area changes gently to maintain the flow stability of the aluminum liquid. The arc surface guides the aluminum liquid to turn smoothly, suppresses the flow separation caused by the sudden change of the cross section, and ensures the continuous transition of the flow rate of each section.

[0007] Optionally, a turbulence suppression groove is provided on the transition guide surface, and the depth of the turbulence suppression groove gradually decreases along the flow direction of the aluminum liquid.

[0008] By adopting the above technical solution, the turbulence suppression groove is designed with a decreasing depth, which gradually weakens the eddy strength when the aluminum liquid flows through the flow rate control node. The groove structure disrupts the formation of large-scale vortices, disperses the turbulent energy into small eddies, reduces oxide peeling and secondary slag involvement. The change in groove depth is synchronized with the flow rate gradient to avoid new flow interference caused by sudden changes in depth and maintain the laminar flow trend of aluminum liquid.

[0009] Optionally, the diversion gap section at the end is connected to a slag collecting bag, and the side of the slag collecting bag away from the flow channel is connected to the hub cavity.

[0010] By adopting the above technical solution, the last diversion gap section is connected to the slag collection bag, and the slag and gas are introduced into the slag collection bag by using the flow inertia of the aluminum liquid. The slag collection bag structure can form a physical isolation barrier, reduce the entry of impurities into the wheel hub cavity, and improve the surface finish and internal quality of the casting.

[0011] Optionally, the top of the slag collecting bag is provided with a gradual vent hole, which includes a tapered section, an expanded section and a spiral guide section which are sequentially connected along the exhaust direction, the aperture of the tapered section gradually decreases along the exhaust direction, the aperture of the expanded section gradually increases along the exhaust direction, and the inner wall of the spiral guide section is provided with a spiral air guide groove; The axis of the gradual vent hole is arranged to be inclined relative to the mainstream direction of the aluminum liquid in the slag collecting bag, so that the gas discharge direction deviates from the central area of ​​the aluminum liquid flow.

[0012] By adopting the above technical solution, during exhaust, the tapered section of the vent accelerates gas discharge by shrinking the aperture, the expanded section expands the flow channel to stabilize the airflow, and the spiral gas guide groove on the inner wall of the spiral guide section forces the gas to spiral up. The axis of the vent is tilted to make the gas discharge path deviate from the mainstream direction of the aluminum liquid, avoiding the high-speed aluminum liquid entraining the gas to form a gas-liquid mixed flow. The gas is discharged in a directional manner along the preset trajectory, reducing the contact time with the aluminum liquid and reducing the impact of oxidation reaction and pressure fluctuation on the filling process.

[0013] Optionally, the rotation direction of the spiral air guide groove is opposite to the rotation direction of the aluminum liquid in the slag collecting bag, and the groove depth of the spiral air guide groove gradually decreases along the exhaust direction.

[0014] By adopting the above technical solution, due to the geometric characteristics of the wheel hub mold, the aluminum liquid will preferentially flow along the circumferential path with the least resistance during the filling process, and it is easy to form a circumferential tangential flow when entering the slag collection bag. By designing the rotation direction of the spiral gas guide groove in the opposite direction to the swirl direction of the aluminum liquid, a reverse shear force can be generated during the gas rising process to destroy the gas-liquid coupling vortex. The groove depth decreases along the exhaust direction to form a gradual flow channel, which promotes a gentle decrease in the gas flow rate and avoids air pressure fluctuations caused by the sudden expansion structure. The reverse rotation design weakens the interference of the aluminum liquid swirl on the gas discharge, improves the exhaust efficiency and maintains the stability of the aluminum liquid flow.

[0015] Optionally, a flow stabilizer is provided at the connection between the diameter expansion section and the spiral guide section. The flow stabilizer is composed of a porous ceramic matrix, and the extension direction of the pores thereof is the same as the exhaust direction.

[0016] By adopting the above technical solution, the flow stabilizer balances the gas flow velocity distribution through the homogeneous channel structure. The extension direction of the channel on the flow stabilizer is consistent with the exhaust direction, guiding the gas to form a laminar flow and suppressing the turbulent regeneration common in the expansion section. The flow stabilizer adopts a porous ceramic matrix, and its high thermal stability ensures that the structural integrity is maintained in a high temperature environment, avoiding thermal deformation from interfering with the gas flow path, which is conducive to extending the service life of the flow stabilizer.

[0017] Optionally, the pouring gate and the corresponding runner constitute an independent pouring unit, and at least two groups of the independent pouring units are provided and are evenly distributed on the side mold along the circumference of the hub cavity.

[0018] By adopting the above technical solution, multiple independent casting units are evenly distributed along the circumference of the hub cavity, so that the aluminum liquid can fill the hub cavity synchronously from multiple points. The diversion gap section of each independent casting unit independently controls the flow rate, balances the circumferential filling pressure distribution, and avoids the temperature gradient difference caused by single-point casting. The ability to cast multiple independent casting units simultaneously is conducive to shortening the filling time, reducing the stress concentration caused by the sequential solidification in the rim area, and improving the hub size accuracy.

[0019] Optionally, it also includes a split pouring cup arranged on the outside of the side mold, the split pouring cup includes a collecting cavity and a branch channel, the collecting cavity is arranged at the top cup mouth end of the split pouring cup, the branch channel is arranged one-to-one corresponding to the independent pouring unit, and one end of the branch channel is connected to the collecting cavity, and the other end is used to be connected to the corresponding pouring port on the side mold.

[0020] By adopting the above technical solution, the branch channels of the split pouring cup correspond to the independent pouring units one by one, ensuring that the aluminum liquid is evenly distributed to each flow channel. The collecting cavity integrates the flow state of the aluminum liquid before diversion, eliminating the flow deviation inside the pouring system. The split design allows the split pouring cup to be disassembled and maintained independently, avoiding the failure of the overall pouring system due to local blockage or wear, and improving the mold maintenance efficiency and process adaptability.

[0021] Optionally, the split pouring cup is connected to the side mold via a detachable connecting component, and the detachable connecting component includes: The mounting seat is arranged at the upper end of the side mold, and the inner wall of the mounting seat is provided with a sealing slot arranged around the pouring port; A sealing boss, adapted to the sealing slot and disposed at the lower end of the split pouring cup, wherein the branch channel runs through the sealing boss; A high temperature resistant thermal expansion sealing ring is embedded on the outer side of the sealing boss.

[0022] By adopting the above technical solution, the sealing slot of the detachable connection component cooperates with the sealing boss, and the high-temperature thermal expansion sealing ring expands at high temperature to achieve tight sealing. After being heated, the high-temperature thermal expansion sealing ring fills the matching gap to prevent aluminum liquid leakage and gas intrusion; after cooling, it shrinks to leave a disassembly gap, which is convenient for quick replacement of the pouring cup. This structure achieves a balance between reliable sealing and convenient maintenance in a high-temperature casting environment, reducing production downtime and extending the service life of the mold.

[0023] In summary, this application includes the following beneficial technical effects: 1. By designing the flow channel into multiple diversion gap sections with decreasing cross-sectional areas, flow rate control nodes are formed to achieve gradient control of the flow velocity of the aluminum liquid. The decreasing mode of the cross-sectional area of ​​each section breaks the traditional linear flow inertia, prompting the aluminum liquid to automatically adjust the flow velocity when flowing through different diversion gap sections, reducing the turbulence and oxidation inclusions caused by sudden changes in flow velocity. The setting of the flow rate control node optimizes the kinetic energy distribution of the aluminum liquid, reduces the turbulence and oxidation inclusions caused by sudden changes in flow velocity, and improves the filling uniformity. The front end of the aluminum liquid enters the hub cavity at a more stable speed, reducing the loose metal structure caused by pressure fluctuations in the rim area and improving the overall density of the casting. At the same time, a concave or convex arc-shaped transition guide surface is set at the flow rate control node to adapt to the flow characteristics under different cross-sectional area change rates. When the cross-sectional area change rate of the upstream diversion gap is large, the transition guide surface is set in an inward concave arc to shrink the flow channel contour, accelerate the aluminum liquid to pass through the node, and prevent local retention; when the upstream cross-sectional area change rate is small, the transition guide surface is set in an outward convex arc to expand the flow channel and maintain the flow stability of the aluminum liquid. The arc surface guides the aluminum liquid to turn smoothly, which is conducive to suppressing flow separation and vortex generation, and ensuring continuous transition of the flow rate of each section. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural diagram of embodiment 1 of the present application.

[0025] Figure 2 It is a cross-sectional view of the turbulence suppression groove in the first embodiment of the present application.

[0026] Figure 3 yes Figure 1 A local enlarged schematic diagram of point A in the middle.

[0027] Figure 4 It is a structural schematic diagram that embodies the overall structure of the side mold in Example 1 of the present application.

[0028] Figure 5 It is a schematic diagram of the overall structure of the second embodiment of the present application.

[0029] Figure 6 yes Figure 5 A local enlarged schematic diagram of point B in the middle.

[0030] Explanation of the reference numerals: 1. side mold; 2. pouring gate; 3. runner; 31. diversion gap section; 32. transition guide surface; 33. turbulence suppression groove; 4. slag collecting bag; 5. gradual air vent; 51. tapering section; 52. diameter expansion section; 53. spiral guide section; 531. spiral air guide groove; 54. flow stabilizer; 6. split pouring cup; 61. collecting cavity; 62. branch channel; 7. detachable connecting assembly; 71. mounting seat; 711. sealing slot; 72. sealing boss; 73. high temperature resistant thermal expansion sealing ring. DETAILED DESCRIPTION

[0031] The following combination Figure 1-Figure 6 , further details of this application are given.

[0032] Embodiment 1:

[0033] The first embodiment of the present application discloses a gravity gap gradient aluminum alloy wheel casting system. Figure 1 A gravity gap gradient aluminum alloy wheel hub casting system is provided on a side mold 1. The casting system includes a pouring port 2 and a runner 3. The pouring port 2 is connected to the runner 3. The outlet end of the runner 3 is used to communicate with the wheel hub cavity. The runner 3 includes a plurality of flow splitting gap sections 31 connected in sequence along the flow direction of the aluminum liquid. The cross-sectional area of ​​each flow splitting gap section 31 is set to decrease along the flow direction of the aluminum liquid, and a flow rate control node is formed between adjacent flow splitting gap sections 31 through the change of cross-sectional area.

[0034] The present application designs the flow channel 3 as a plurality of diverter gap sections 31 with decreasing cross-sectional areas to form a flow rate control node, thereby realizing gradient control of the flow rate of the aluminum liquid. The decreasing pattern of the cross-sectional area of ​​each section breaks the traditional linear flow inertia, prompting the aluminum liquid to automatically adjust the flow rate when flowing through different diverter gap sections 31, thereby reducing the turbulence and oxidation inclusions caused by sudden changes in flow rate. The setting of the flow rate control node optimizes the kinetic energy distribution of the aluminum liquid, reduces the turbulence and oxidation inclusions caused by sudden changes in flow rate, and improves the filling uniformity. The front end of the aluminum liquid enters the hub cavity at a more stable speed, reducing the loosening of the metal structure caused by pressure fluctuations in the rim area, and improving the overall density of the casting.

[0035] Reference Figure 1 , a transition guide surface 32 is provided at the flow velocity control node, and satisfies: when the cross-sectional area change rate of the upstream diverter gap section 31 is greater than that of the downstream, the transition guide surface 32 is set in an inward concave arc; when the cross-sectional area change rate of the upstream diverter gap section 31 is less than that of the downstream, the transition guide surface 32 is set in an outward convex arc. A transition guide surface 32 with an inward concave or outward convex arc is set at the flow velocity control node to adapt to the flow characteristics under different cross-sectional area change rates. When the cross-sectional area change rate of the upstream diverter gap section 31 is large, the transition guide surface 32 is set in an inward concave arc to shrink the contour of the flow channel 3, accelerate the aluminum liquid to pass through the node, and prevent local retention; when the cross-sectional area change rate of the upstream is small, the transition guide surface 32 is set in an outward convex arc to expand the flow channel 3 and maintain the flow stability of the aluminum liquid. And the arc surface can guide the aluminum liquid to turn smoothly, which is conducive to suppressing flow separation and vortex generation, and ensuring continuous transition of the flow velocity of each section.

[0036] Reference Figure 2, a turbulence suppression groove 33 is provided on the transition guide surface 32, and the depth of the turbulence suppression groove 33 gradually decreases along the flow direction of the aluminum liquid. In this way, the turbulence suppression groove 33 is designed with a decreasing depth, and the eddy strength is gradually weakened when the aluminum liquid flows through the flow velocity control node. The groove structure disrupts the formation of large-scale vortices, disperses the turbulent energy into tiny eddies, reduces oxide peeling and secondary slag involvement. The change in groove depth is synchronized with the flow velocity gradient to avoid new flow disturbances caused by sudden changes in depth, and maintain the laminar flow trend of the aluminum liquid.

[0037] Reference Figure 1 The end of the split flow gap section 31 is connected to the slag collecting bag 4, and the slag and gas are introduced into the slag collecting bag 4 by using the flow inertia of the aluminum liquid. The side of the slag collecting bag 4 away from the flow channel 3 is connected to the wheel hub cavity, so that the clean aluminum liquid enters the cavity molding area first, and the slag-containing aluminum liquid is retained in the slag collecting bag 4. The slag collecting bag 4 forms a physical isolation barrier, reduces the risk of impurities entering the wheel hub cavity, and is conducive to improving the surface finish and internal structure quality of the casting.

[0038] Reference Figure 1 and Figure 3 The top of the slag collecting bag 4 is provided with a gradual vent hole 5, which can guide the gas to be discharged along the edge of the slag collecting bag 4, which is conducive to prolonging the residence time of the gas in the slag collecting bag 4, promoting the floating of tiny slag to the top of the slag collecting bag 4, and enhancing its filtering effect. The gradual vent hole 5 includes a tapered section 51, an expanded diameter section 52 and a spiral guide section 53 which are sequentially connected along the exhaust direction. The aperture of the tapered section 51 gradually decreases along the exhaust direction, and the aperture of the expanded diameter section 52 gradually increases along the exhaust direction. The inner wall of the spiral guide section 53 is provided with a spiral gas guide groove 531. The overall axis of the gradual vent hole 5 is inclined relative to the mainstream direction of the aluminum liquid in the slag collecting bag 4, so that the gas discharge direction deviates from the central area of ​​the aluminum liquid flow.

[0039] During exhaust, the aperture of the tapered section 51 gradually decreases to form a Venturi effect, accelerates gas flow, forces the gas to quickly leave the slag bag 4, and prevents the gas from forming trapped bubbles on the surface of the molten aluminum. The sudden increase in the aperture of the expanded section 52 significantly reduces the gas flow rate, preventing the high-speed airflow from disturbing the surface of the molten aluminum, causing the oxide scale to rupture or the secondary entrapment of slag. The spiral gas guide groove 531 on the inner wall of the spiral guide section 53 changes the gas flow pattern through geometric constraints, converting the originally disordered eddy current into a directional spiral motion, reducing the contact area between the gas and the molten aluminum, and indirectly reducing the probability of oxidation reaction. The inclined design of the axis of the gradient vent 5 relative to the mainstream direction of the molten aluminum in the slag bag 4 causes the gas discharge direction to deviate from the core area of ​​the molten aluminum flow, avoiding the high-speed molten aluminum entraining the gas to form turbulence, thereby reducing the internal porosity defects of the casting.

[0040] Reference Figure 3A flow stabilizer 54 is fixed at the connection between the expansion section 52 and the spiral guide section 53. The flow stabilizer 54 is composed of a porous ceramic matrix, and the extension direction of its pores is the same as the exhaust direction. The flow stabilizer 54 balances the gas flow velocity distribution through a homogeneous pore structure. The extension direction of the pores on the flow stabilizer 54 is consistent with the exhaust direction, guiding the gas to form a laminar flow and suppressing the turbulent regeneration common in the expansion section 52. The porous structure of the flow stabilizer 54 also disperses the gas flow energy, reduces the impact and wear of the air flow on the spiral guide section 53, and extends the service life of the vent. At the same time, the high thermal stability of the ceramic matrix ensures that the structural integrity is maintained in a high temperature environment, avoids thermal deformation from affecting the accuracy of the gas flow path, and indirectly ensures the durability of the exhaust effect.

[0041] Reference Figure 1 Due to the geometric characteristics of the wheel hub mold, the aluminum liquid will preferentially flow along the circumferential path with the least resistance during the filling process, and it is easy to form a circumferential tangential flow when entering the slag bag 4. In order to facilitate the generation of reverse shear force during the gas rising and discharging process and destroy the turbulence of the gas-liquid cross section, the spiral gas guide groove 531 is opposite to the swirl direction of the aluminum liquid in the slag bag 4. In this way, the momentum transfer between the gas and the aluminum liquid can be weakened, and the risk of oxide scale peeling and slag dispersion can be reduced. At the same time, the groove depth of the spiral gas guide groove 531 gradually decreases along the exhaust direction to promote the gas flow rate to decrease smoothly during the discharge, avoid the pressure shock caused by the sudden expansion structure, and adjust the contact strength between the gas and the aluminum liquid through the gradual groove depth. While ensuring the exhaust efficiency, the interference of the gas on the flow of the aluminum liquid is reduced, thereby improving the filling integrity of the wheel hub cavity.

[0042] Reference Figure 4 In order to facilitate the aluminum liquid to fill the hub cavity synchronously from multiple points, the pouring port 2 and the corresponding runner 3 constitute independent pouring units. At least two groups of independent pouring units are provided and are evenly distributed on the side mold 1 along the circumference of the hub cavity. The diversion gap section 31 of each independent pouring unit independently regulates the flow rate, balances the circumferential filling pressure distribution, and avoids the temperature gradient difference caused by single-point pouring. In addition, the ability to pour multiple independent pouring units synchronously is conducive to shortening the filling time, reducing the stress concentration caused by the sequential solidification in the rim area, and improving the hub size accuracy.

[0043] Embodiment 2:

[0044] The second embodiment of the present application discloses a gravity gap gradient aluminum alloy wheel casting system. Figure 5, the difference between the second embodiment and the first embodiment is that: the casting system also includes a split pouring cup 6 arranged on the outside of the side mold 1, the split pouring cup 6 includes a collecting cavity 61 and a branch channel 62, the collecting cavity 61 is arranged at the top cup end of the split pouring cup 6, the branch channel 62 is arranged one-to-one with the independent pouring unit, and one end of the branch channel 62 is connected to the collecting cavity, and the other end is used to be connected to the pouring port 2 on the side mold 1. When using the split pouring cup 6, its branch channel 62 corresponds one-to-one with the independent pouring unit, which can ensure that the aluminum liquid is evenly distributed to each flow channel 3; the collecting cavity 61 integrates the flow state of the aluminum liquid before diversion, which is conducive to eliminating the flow deviation inside the casting system. The split design allows the split pouring cup 6 to be independently disassembled and maintained, avoiding failure of the overall pouring system due to local blockage or wear, and improving mold maintenance efficiency and process adaptability.

[0045] Reference Figure 5 and Figure 6 The split pouring cup 6 is connected to the side mold 1 through a detachable connecting component 7, and the detachable connecting component 7 includes a mounting seat 71, a sealing boss 72 and a high temperature thermal expansion sealing ring 73: wherein the mounting seat 71 is integrally formed at the upper end of the side mold 1, and the inner wall of the mounting seat 71 is provided with a sealing slot 711 arranged around the pouring port 2; the sealing boss 72 is adapted to the sealing slot 711 and is integrally formed at the lower end of the split pouring cup 6, and the branch channel 62 runs through the sealing boss 72; the high temperature thermal expansion sealing ring 73 is embedded on the outer side of the sealing boss 72. In the second embodiment, the high temperature thermal expansion sealing ring 73 is composed of an expanded graphite tape and a ceramic fiber layer wound on the outer side of the expanded graphite tape, which can completely fill the gap between the sealing boss 72 and the sealing slot 711 after thermal expansion at a predetermined temperature.

[0046] When in use, the sealing slot 711 of the detachable connection component 7 cooperates with the sealing boss 72, and the high temperature resistant thermal expansion sealing ring 73 expands at high temperature to achieve tight sealing. After being heated, the high temperature resistant thermal expansion sealing ring 73 fills the matching gap to prevent aluminum liquid leakage and gas intrusion; after cooling, it shrinks to leave a disassembly gap, which is convenient for quick replacement of the pouring cup. In this way, through the setting of the detachable connection component 7, a balance between reliable sealing and convenient maintenance can be achieved in a high temperature casting environment, reducing production downtime and helping to extend the service life of the mold.

[0047] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A gravity gap gradient aluminum alloy wheel hub casting system, arranged on a side mold (1), comprising a pouring port (2) and a runner (3), wherein the pouring port (2) is connected to the runner (3), and the outlet end of the runner (3) is connected to the wheel hub cavity, characterized in that: The flow channel (3) comprises a plurality of flow diversion gap sections (31) connected in sequence along the flow direction of the aluminum liquid, the cross-sectional area of ​​each of the flow diversion gap sections (31) is arranged to decrease along the flow direction of the aluminum liquid, and a flow rate control node is formed between adjacent flow diversion gap sections (31) by changing the cross-sectional area, and a transition guide surface (32) is provided at the flow rate control node; When the rate of change of the cross-sectional area at the beginning and end of the upstream diversion gap section (31) is greater than that at the downstream, the transition guide surface (32) is arranged in an inwardly concave arc shape; When the rate of change of the cross-sectional area at the beginning and end of the upstream diversion gap section (31) is smaller than that at the downstream, the transition guide surface (32) is arranged in an outwardly convex arc shape.

2. The gravity gap gradient aluminum alloy wheel casting system according to claim 1, characterized in that: The transition guide surface (32) is provided with a turbulence suppression groove (33), and the depth of the turbulence suppression groove (33) gradually decreases along the flow direction of the aluminum liquid.

3. The gravity gap gradient aluminum alloy wheel casting system according to claim 1, characterized in that: The flow dividing gap section (31) at the end is connected to a slag collecting bag (4), and the side of the slag collecting bag (4) away from the flow channel (3) is connected to the hub cavity.

4. The gravity gap gradient aluminum alloy wheel casting system according to claim 3 is characterized by: The top of the slag collecting bag (4) is provided with a gradual vent hole (5), which comprises a tapered section (51), an expanded section (52) and a spiral guide section (53) which are sequentially connected along the exhaust direction, the aperture of the tapered section (51) gradually decreases along the exhaust direction, the aperture of the expanded section (52) gradually increases along the exhaust direction, and the inner wall of the spiral guide section (53) is provided with a spiral air guide groove (531); The axis of the gradual vent hole (5) is arranged to be inclined relative to the mainstream direction of the aluminum liquid in the slag collecting bag (4), so that the gas discharge direction deviates from the central area of ​​the aluminum liquid flow.

5. The gravity gap gradient aluminum alloy wheel casting system according to claim 4 is characterized in that: The spiral direction of the spiral air guide groove (531) is opposite to the swirl direction of the aluminum liquid in the slag collecting bag (4), and the groove depth of the spiral air guide groove (531) gradually decreases along the exhaust direction.

6. The gravity gap gradient aluminum alloy wheel casting system according to claim 4, characterized in that: A flow stabilizer (54) is provided at the connection between the diameter expansion section (52) and the spiral flow guide section (53); the flow stabilizer (54) is composed of a porous ceramic matrix, and the extension direction of its pores is the same as the exhaust direction.

7. The gravity gap gradient aluminum alloy wheel casting system according to claim 1, characterized in that: The pouring port (2) and the corresponding flow channel (3) constitute an independent pouring unit. The independent pouring units are provided in at least two groups and are evenly distributed on the side mold (1) along the circumference of the hub cavity.

8. The gravity gap gradient aluminum alloy wheel casting system according to claim 7, characterized in that: It also includes a split pouring cup (6) arranged on the outside of the side mold (1), the split pouring cup (6) including a collecting cavity (61) and a branch channel (62), the collecting cavity (61) is arranged at the top cup end of the split pouring cup (6), the branch channel (62) is arranged in a one-to-one correspondence with the independent pouring unit, and one end of the branch channel (62) is connected to the collecting cavity, and the other end is used for corresponding communication with the pouring port (2) on the side mold (1).

9. The gravity gap gradient aluminum alloy wheel casting system according to claim 8, characterized in that: The split pouring cup (6) is connected to the side mold (1) via a detachable connecting component (7), and the detachable connecting component (7) comprises: A mounting seat (71) is arranged at the upper end of the side mold (1), and an inner wall of the mounting seat (71) is provided with a sealing slot (711) arranged around the pouring port (2); A sealing boss (72) adapted to the sealing slot (711) and disposed at the lower end of the split pouring cup (6), wherein the branch channel (62) passes through the sealing boss (72); A high temperature resistant thermal expansion sealing ring (73) is embedded on the outer side of the sealing boss (72).

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