A squeeze casting pouring system and method for an aluminum alloy balanced suspension large support

Abstract

This invention discloses a squeeze casting system and method for an aluminum alloy balance suspension large support, comprising an upper mold and a lower mold. The upper mold has a first chamber and a second chamber, while the lower mold has a third chamber and a fourth chamber arranged in parallel at intervals. The first and third chambers are coaxially arranged, as are the second and fourth chambers. The first and third chambers have a first contoured inner wall corresponding to the shape of an annular material cake, and the second and fourth chambers have a second contoured inner wall corresponding to the shape of the aluminum alloy balance suspension large support. The upper mold has a flow channel for connecting the second and third chambers. A central squeeze pin is located in the first chamber, a liquid lifting system is located in the third chamber, and a partial squeeze pin is located in the second chamber. This invention significantly improves casting quality and production efficiency, and has good engineering application value.

Description

Technical Field

[0001] This invention relates to the field of extrusion casting technology, and in particular to an extrusion casting system and method for a large support of an aluminum alloy balance suspension. Background Technology

[0002] In existing technologies, the production of support castings mainly adopts the traditional extrusion casting process. This process typically uses an upward extrusion method, the basic principle of which is to use a punch to force molten aluminum from a cup upward into the mold cavity, and extrusion is performed immediately after the molten aluminum has filled the cavity.

[0003] However, this traditional process has the following technical problems:

[0004] First, during the production process, molten aluminum needs to be poured into a melting cup. During this process, the molten aluminum easily forms oxide scale upon contact with air. This oxide scale will enter the mold cavity along with the molten aluminum, ultimately causing inclusion defects inside the casting and seriously affecting the internal quality of the casting.

[0005] Secondly, in actual production operations, the melting cup must be kept tilted before adding molten aluminum. After the molten aluminum is added, the melting cup must first be rotated to a vertical position before it can be raised to complete the filling and extrusion process of the cavity. This process results in a long production cycle, affecting production efficiency and hindering large-scale production.

[0006] Therefore, there is an urgent need to develop a new type of extrusion casting process for support castings to solve the above-mentioned technical problems. Summary of the Invention

[0007] The technical problem to be solved by this invention is to provide a squeeze casting system and method for aluminum alloy balance suspension large support, which addresses the deficiencies in the existing technology. This invention solves the technical problems existing in the traditional process. By combining the relevant characteristics of low-pressure casting and squeeze casting, this invention adopts a method that combines low-pressure filling and squeeze solidification to complete the casting process. Compared with the traditional squeeze casting method and equipment, the castings of this invention have the advantages of less oxide inclusions and shorter production cycle.

[0008] The technical solution adopted by this invention to solve its technical problem is as follows: This invention provides an extrusion casting system for a large support of an aluminum alloy balance suspension, including an upper mold and a lower mold. The upper mold is provided with a first chamber and a second chamber arranged in parallel and spaced apart. The lower mold is provided with a third chamber and a fourth chamber arranged in parallel and spaced apart. The first chamber and the third chamber are coaxially arranged, and the second chamber and the fourth chamber are coaxially arranged. The first chamber and the third chamber are provided with a first contoured inner wall corresponding to the shape of the annular material cake. The second chamber and the fourth chamber are provided with a second contoured inner wall corresponding to the shape of the large support of the aluminum alloy balance suspension. The upper mold is provided with a flow channel for connecting the second chamber and the third chamber. The first chamber is provided with a central extrusion pin. The third chamber is provided with a liquid lifting system. The second chamber is provided with a partial extrusion pin.

[0009] In a preferred embodiment of the present invention, the liquid lifting system includes a liquid lifting pipe oil heating assembly, a liquid lifting port sleeve, and a liquid lifting port, which are coaxially arranged in the third chamber.

[0010] In a preferred embodiment of the present invention, a central extrusion pin outer bushing is provided in the first chamber, a central extrusion pin connecting rod is coaxially fixed to the central extrusion pin outer bushing, and a central extrusion pin is coaxially fixed to the lower part of the central extrusion pin connecting rod.

[0011] In a preferred embodiment of the present invention, a central extrusion pin cooling water pipe is coaxially fixed inside the central extrusion pin connecting rod, and the central extrusion pin cooling water pipe is located in communication with the central cavity of the central extrusion pin.

[0012] This invention also discloses a method for forming a large support for an aluminum alloy balance suspension based on an extrusion casting gating system. The method involves calculating the filling volume based on the weight of the molten aluminum filling the cavity; determining the diameter of the riser and the outer diameter of the small end of the central extrusion pin within a suitable filling time and under the condition that the flow rate at the riser is no greater than 50 cm / s; calculating the required extrusion volume of the casting based on the casting volume; and calculating the outer diameter of the annular cake and the extrusion stroke based on the required extrusion volume, wherein the outer diameter of the annular cake is equal to the outer diameter of the large end of the central extrusion pin and the inner diameter of the outer bushing of the central extrusion pin.

[0013] In a preferred embodiment of the present invention, a local feeding boss is provided on the casting body, and the height and diameter of the boss are determined according to the required volume of feeding aluminum liquid, thereby determining the diameter and extrusion stroke of the local extrusion pin.

[0014] In a preferred embodiment of the present invention, a local feeding boss is provided on the casting body, and the height and diameter of the boss are determined according to the required volume of feeding aluminum liquid, thereby determining the diameter and extrusion stroke of the local extrusion pin.

[0015] In a preferred embodiment of the present invention, a matching central extrusion pin outer bushing, a liquid riser sleeve, and a local extrusion pin bushing are respectively provided for the central extrusion pin and the local extrusion pin.

[0016] In a preferred embodiment of the present invention, an oil heating assembly for the riser pipe is provided around the periphery of the riser port to raise the temperature of the riser port and prevent the aluminum liquid from freezing; the central extrusion pin is designed as a hollow structure, and the inner cavity of the central extrusion pin is cooled by water circulation through a central extrusion pin cooling water pipe; a central extrusion pin connecting rod is provided for connecting the central extrusion pin to the casting equipment.

[0017] In a preferred embodiment of the present invention, the partial extrusion pin is designed as a hollow structure, and the inner cavity of the partial extrusion pin is cooled by water circulation through a cooling water pipe.

[0018] The beneficial effects of this invention are: it not only has the advantages of simple structure and convenient assembly, but also solves the technical problems existing in traditional processes. Furthermore, through a series of innovative designs, it significantly improves the quality of castings and production efficiency, and has good engineering application value.

[0019] This invention effectively avoids the oxide scale problem caused by pouring molten aluminum into the melting cup in traditional processes by precisely calculating and controlling the weight and volume of the molten aluminum filling the mold cavity and the flow rate at the riser. This significantly reduces slag inclusions in the casting and improves the internal quality of the casting. Furthermore, by eliminating the need to rotate the melting cup from an inclined to a vertical position, the production cycle is greatly shortened, increasing production efficiency.

[0020] This invention effectively solves the technical problem of shrinkage porosity in thick parts of castings by setting local feeding bosses and rationally designing the size parameters of the bosses and the specifications of the local extrusion pins according to the volume of the feeding aluminum liquid, thus ensuring the density and mechanical properties of the castings. Furthermore, the central extrusion pin and the local extrusion pins adopt a hollow structure design, combined with a water-cooling system for circulating cooling, which not only extends the service life of key components but also improves the stability and reliability of equipment operation.

[0021] During the process, the oil heating assembly at the riser port effectively preheated the riser, preventing premature solidification of the molten aluminum and ensuring the filling quality of the casting. The use of various matching bushings ensured precise guidance of moving parts, improving process controllability and casting dimensional accuracy. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0023] Figure 1This is a schematic diagram of the extrusion casting system of an aluminum alloy balance suspension large support according to an embodiment of the present invention before extrusion.

[0024] Figure 2 This is a schematic diagram of the extrusion casting system of an aluminum alloy balance suspension large support according to an embodiment of the present invention after extrusion.

[0025] Figure 3 This is a schematic diagram of the large support of the balance suspension for commercial heavy-duty trucks before compression, according to an embodiment of the present invention.

[0026] Figure 4 This is a schematic diagram of the large support of the balance suspension of a commercial vehicle heavy truck after compression, according to an embodiment of the present invention.

[0027] Figure 5 This is a schematic diagram of the large support of the balance suspension for heavy-duty commercial vehicles according to an embodiment of the present invention;

[0028] Figure 6 This is a schematic diagram of an existing extrusion casting device;

[0029] In the diagram, 1-Central extrusion pin connecting rod (connected to the equipment); 2-Central extrusion pin outer bushing; 3-Central extrusion pin; 4-Central extrusion pin cooling water pipe; 5-Upper die; 6-Annular cake; 7-Lower die; 8-Liquid riser port oil heating assembly; 9-Liquid riser port sleeve; 10-Liquid riser port; 11-Casting; 12-Casting partial extrusion boss; 13-Partial extrusion pin; 14-Partial extrusion pin cooling water pipe; 15-Partial extrusion pin bushing. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0031] The present invention will be further described in detail below with reference to specific embodiments. For example... Figure 1-5 As shown, this embodiment takes the large support of the balance suspension of a heavy-duty commercial truck as an example. This support is a large, high-strength chassis structural component of lightweight aluminum alloy for automobiles. The casting outline dimensions are 690mm long × 635mm wide × 390mm high, and the casting weight is 23.64kg. The maximum wall thickness is 50mm, and the main wall thickness is 10mm.

[0032] The extrusion casting system of this invention mainly includes an upper mold 5 and a lower mold 7. The upper mold 5 has a first chamber and a second chamber arranged in parallel at intervals, and the lower mold 7 has a third chamber and a fourth chamber arranged in parallel at intervals. The first and third chambers are coaxially arranged, as are the second and fourth chambers. The first and third chambers have a first contoured inner wall corresponding to the shape of the annular material cake 6, while the second and fourth chambers have a second contoured inner wall corresponding to the shape of the large support of the aluminum alloy balance suspension. The upper mold 5 also has a flow channel for connecting the second and third chambers.

[0033] In the specific structural design, a central extrusion pin 3 is installed in the first chamber, a liquid lifting system is installed in the third chamber, and a partial extrusion pin 14 is installed in the second chamber. The liquid lifting system consists of a liquid lifting pipe oil heating assembly 8, a liquid lifting port sleeve 9, and a liquid lifting port 10, all coaxially arranged in the third chamber. A central extrusion pin outer bushing 2 is installed in the first chamber, on which a central extrusion pin connecting rod 1 is coaxially fixed. A central extrusion pin 3 is coaxially fixed below the connecting rod. A central extrusion pin cooling water pipe 4 is coaxially fixed inside the central extrusion pin connecting rod 1, and this water pipe communicates with the central cavity of the central extrusion pin 3.

[0034] The specific implementation steps of this invention are as follows:

[0035] First, the filling volume is calculated based on the weight of the molten aluminum filling the cavity. Within a suitable filling time, and ensuring the flow rate at the riser port does not exceed 50 cm / s, the diameter of the riser port 10 is calculated and determined. This diameter also determines the outer diameter of the small end of the central extrusion pin 3. Subsequently, the required extrusion volume of the casting is calculated based on the casting volume. Based on the required extrusion volume, the outer diameter of the annular cake (i.e., the outer diameter of the large end of the central extrusion pin 3 and the inner diameter of the central extrusion pin outer bushing 2) and the required extrusion stroke (i.e., the length of the outer diameter of the small end of the central extrusion pin) are calculated.

[0036] To address the shrinkage porosity issue that may occur in thick sections of castings, this invention incorporates a local feeding boss 12 on the casting body. The height and diameter of the boss are determined based on the required volume of molten aluminum for feeding, which in turn determines the diameter and extrusion stroke of the local extrusion pin 13. Since both the central extrusion pin 3 and the local extrusion pin 13 are moving parts, a central extrusion pin outer bushing 2, a liquid riser sleeve 9, and a local extrusion pin bushing 15 are designed to complement them.

[0037] In the initial production stage, considering that the mold is at room temperature, an oil heating assembly 8 is installed around the riser port to prevent the molten aluminum from freezing. During continuous production, since the central extrusion pin and the partial extrusion pin need to repeatedly contact the high-temperature molten aluminum, both adopt a hollow structure design to extend their service life and ensure smooth movement, and are cooled by their respective cooling water pipes. Specifically, the central extrusion pin is cooled by the central extrusion pin cooling water pipe 4, while the partial extrusion pin is cooled by its dedicated cooling water pipe 14. In addition, a central extrusion pin connecting rod is specially designed to connect the central pin to the casting equipment.

[0038] The casting system of the present invention can be adaptively designed according to actual needs, mainly including the following three aspects:

[0039] 1. The diameter of the riser port 10 can be calculated and determined based on the volume of molten aluminum required to fill the mold cavity, provided the flow rate at the riser port does not exceed 50 cm / s. Calculation formula: Casting volume (cm) 3 Casting weight (g) / density (g / cm³) 3 Filling time: 3–7 seconds; Flow rate: generally less than 50 cm / s

[0040] 2. The outer diameter of the large end and the length of the small end of the central extrusion pin 3 can be calculated based on the required extrusion volume. Calculation formula: Extrusion volume / casting volume ≥ 6%; Extrusion stroke = 1.0~1.3 liters, nozzle diameter

[0041] 3. The volume of the local extrusion boss 12 in the casting can be calculated based on the amount of aluminum liquid required for local feeding in the casting. Calculation formula: Local extrusion volume (local feeding boss volume) / Aluminum liquid volume of the feeding area ≥ 2, generally feeding boss diameter / height = 1 ~ 1.5.

[0042] It should be noted that the calculation formula disclosed herein is not part of the prior art; it is an empirical formula that makes a substantial contribution to the inventiveness of the invention.

[0043] Example 1: In this example, the casting is a large support for the balance suspension of a heavy-duty commercial truck. The casting dimensions are 690mm (length) × 635mm (width) × 390mm (height), and the casting weight is 23.64kg. The maximum wall thickness is 50mm, and the main wall thickness is 10mm. The calculated volume of molten aluminum filling the cavity is 9456cm³. 3 With a filling time of 6 seconds and a flow rate of 45 cm / s at the riser, the calculated riser diameter is 67 mm, but 70 mm is actually selected. The casting volume is 9456 cm³. 3 The required extrusion volume is calculated to be 567.36 cm³.3 The extrusion stroke is set to 85mm, and the calculated outer diameter of the annular material cake is 115.7mm. Since 120mm is actually selected, the outer diameter of the large end of the central extrusion pin is 120mm, and the inner diameter of the central extrusion pin bushing is also 120mm. A local feeding boss with a height of 30mm and a diameter of 35mm is set at the maximum wall thickness of the casting. The corresponding local extrusion pin diameter is 35mm, and the extrusion stroke is 30mm.

[0044] Example 2: In this example, the casting is a medium-sized balance suspension large support, with dimensions of 580mm (length) × 525mm (width) × 320mm (height), a weight of 18.36kg, a maximum wall thickness of 45mm, and a main body wall thickness of 8mm. The calculated volume of molten aluminum filling the cavity is 7344cm³. 3 With a filling time of 6 seconds and a flow rate of 42 cm / s at the riser, the calculated riser diameter is 60.9 mm. A diameter of 60 mm is actually chosen, based on the casting volume of 7344 cm³. 3 The required extrusion volume was calculated to be 440.64 cm³. 3 The extrusion stroke is set to 75mm, and the calculated outer diameter of the annular cake is 105.3mm. A diameter of 110mm is actually selected, so the outer diameter of the large end of the central extrusion pin is 110mm, and the inner diameter of the central extrusion pin bushing is also 110mm. A local feeding boss with a height of 28mm and a diameter of 32mm is set at the maximum wall thickness of the casting. The corresponding local extrusion pin diameter is 32mm, and the extrusion stroke is 28mm.

[0045] Example 3: In this example, the casting is a lightweight balance suspension large support, with dimensions of 520mm (length) × 460mm (width) × 280mm (height), a weight of 15.42kg, a maximum wall thickness of 40mm, and a main body wall thickness of 7mm. The calculated volume of molten aluminum filling the cavity is 6168cm³. 3 With a filling time of 5 seconds and a flow rate of 40 cm / s at the riser, the calculated riser diameter is 62.6 mm. A diameter of 65 mm is actually chosen, based on the casting volume of 6168 cm³. 3 The calculated required extrusion volume is 370.08 cm³. 3 The extrusion stroke is set to 70mm, and the calculated outer diameter of the annular material cake is 104.6mm. A diameter of 105mm is actually selected, so the outer diameter of the large end of the central extrusion pin is 105mm, and the inner diameter of the central extrusion pin bushing is also 105mm. A local feeding boss with a height of 26mm and a diameter of 30mm is set at the maximum wall thickness of the casting. The corresponding local extrusion pin diameter is 30mm, and the extrusion stroke is 26mm.

[0046] The above three embodiments demonstrate that the extrusion casting gating system of the present invention can be flexibly adapted to balance suspension large supports of different specifications. By adjusting key parameters such as the diameter of the liquid riser, the size of the central extrusion pin, and the parameters of the local feeding boss, the production needs of castings of different sizes and weights can be met, while ensuring the quality of the castings and production efficiency. Practice has proven that the castings produced using the process method of the present invention have a dense internal structure, no obvious shrinkage defects, and good mechanical properties, fully meeting the usage requirements.

[0047] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0048] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0049] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A squeeze casting system for a large support of an aluminum alloy balance suspension, comprising an upper mold (5) and a lower mold (7), characterized in that, The upper mold (5) is provided with a first chamber and a second chamber arranged in parallel and spaced apart. The lower mold (7) is provided with a third chamber and a fourth chamber arranged in parallel and spaced apart. The first chamber and the third chamber are arranged coaxially. The second chamber and the fourth chamber are arranged coaxially. The first chamber and the third chamber are provided with a first contoured inner wall corresponding to the shape of the annular material cake (6). The second chamber and the fourth chamber are provided with a second contoured inner wall corresponding to the shape of the large support of the aluminum alloy balance suspension. The upper mold (5) is provided with a flow channel for connecting the second chamber and the third chamber. The first chamber is provided with a central extrusion pin (3). The third chamber is provided with a liquid lifting system. The second chamber is provided with a partial extrusion pin (14).

2. The extrusion casting system for the large support of the aluminum alloy balance suspension according to claim 1, characterized in that, The liquid lifting system includes a liquid lifting pipe oil heating assembly (8), a liquid lifting port sleeve (9), and a liquid lifting port (10) arranged coaxially in the third chamber.

3. The extrusion casting system for the large support of the aluminum alloy balance suspension according to claim 1, characterized in that, The first chamber is provided with a central extrusion pin outer bushing (2), and a central extrusion pin connecting rod (1) is coaxially fixed to the central extrusion pin outer bushing (2). A central extrusion pin (3) is coaxially fixed to the lower part of the central extrusion pin connecting rod (1).

4. The extrusion casting system for the large support of the aluminum alloy balance suspension according to claim 3, characterized in that, The central extrusion pin connecting rod (1) is coaxially fixed with a central extrusion pin cooling water pipe (4), which is located in communication with the central cavity of the central extrusion pin (3).

5. A method for forming an aluminum alloy balance suspension large support based on the extrusion casting gating system according to any one of claims 1-4, characterized in that, Calculate the filling volume based on the weight of the molten aluminum filling the cavity; determine the diameter of the riser port (i.e., the outer diameter of the small end of the central extrusion pin) within an appropriate filling time and under the condition that the flow rate at the riser port is not greater than 50 cm / s; calculate the required extrusion volume of the casting based on the casting volume; and calculate the outer diameter of the annular cake and the extrusion stroke based on the required extrusion volume, wherein the outer diameter of the annular cake is equal to the outer diameter of the large end of the central extrusion pin and the inner diameter of the outer bushing of the central extrusion pin.

6. The method for forming a large support for a balanced aluminum alloy suspension according to claim 5, characterized in that, A local feeding boss is set on the casting body, and the height and diameter of the boss are determined according to the required volume of feeding aluminum liquid, thereby determining the diameter and extrusion stroke of the local extrusion pin.

7. The method for forming a large support for a aluminum alloy balance suspension according to claim 5, characterized in that, A local feeding boss is set on the casting body, and the height and diameter of the boss are determined according to the required volume of feeding aluminum liquid, thereby determining the diameter and extrusion stroke of the local extrusion pin.

8. The method for forming a large support for an aluminum alloy balance suspension according to claim 5, characterized in that, A matching outer bushing for the central extrusion pin, a liquid riser sleeve, and a bushing for the local extrusion pin are respectively provided.

9. The method for forming a large support for an aluminum alloy balance suspension according to claim 5, characterized in that, A riser pipe oil heating assembly is installed around the perimeter of the riser port to raise the temperature of the riser port and prevent the aluminum liquid from freezing; the central extrusion pin is designed as a hollow structure and the inner cavity of the central extrusion pin is cooled by water circulation through the central extrusion pin cooling water pipe. A central extrusion pin connecting rod is provided for connecting the central extrusion pin to the casting equipment.

10. The method for forming a large support for an aluminum alloy balance suspension according to claim 5, characterized in that, The partial extrusion pin is designed as a hollow structure, and the internal cavity of the partial extrusion pin is cooled by water circulation through the partial extrusion pin cooling water pipe.

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