Extrusion casting pouring system and method for aluminum alloy balanced suspension large support

Abstract

The extrusion casting pouring system comprises an upper die and a lower die, the upper die is provided with a first cavity and a second cavity, the lower die is provided with a third cavity and a fourth cavity which are arranged in parallel in a spaced mode, the first cavity and the third cavity are coaxially arranged, and the second cavity and the fourth cavity are coaxially arranged. The second cavity and the fourth cavity are coaxially arranged, first profiling inner walls corresponding to the annular material cake in shape are arranged in the first cavity and the third cavity, and the second cavity and the fourth cavity are used for second profiling inner walls corresponding to the aluminum alloy balanced suspension large support in shape. The upper die is provided with a runner used for achieving communication of the second cavity and the third cavity, a center extrusion pin is arranged in the first cavity, a liquid lifting system is arranged in the third cavity, and a local extrusion pin is arranged in the second cavity. The casting quality and the production efficiency are remarkably improved, and good engineering application value is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of extrusion casting, and in particular to an extrusion casting pouring system and method for a large support of an aluminum alloy balanced suspension. Background Art

[0002] In the prior art, the production of bracket castings mainly adopts the traditional extrusion casting process. This process usually adopts the upward extrusion method, the basic principle of which is to use a punch to squeeze the aluminum liquid in the melting cup upward into the mold cavity, and then immediately extrude it after the aluminum liquid fills the cavity.

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

[0004] First, during the production process, the aluminum liquid needs to be poured into the melting cup. During this process, the aluminum liquid is easily exposed to the air to produce oxide scale, which will enter the mold cavity along with the aluminum liquid, eventually causing slag inclusion defects inside the casting, 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 rise to complete the cavity filling and extrusion process. This process results in a long production cycle, affects production efficiency, and is not conducive to large-scale production.

[0006] Therefore, it is urgent to develop a new type of bracket casting extrusion casting process to solve the above technical problems. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide an extrusion casting pouring system and method for a large support of an aluminum alloy balanced suspension in view of the defects in the prior art, which solves the technical problems existing in the traditional process. The present invention combines the relevant characteristics of low-pressure casting and extrusion casting, and adopts a method combining low-pressure filling and extrusion solidification to complete the casting process of the casting. Compared with the traditional extrusion casting method and device, the casting of the present invention has the advantages of less oxidation slag inclusions and a short production cycle.

[0008] The technical solution adopted by the present invention to solve its technical problems is: the present invention provides an extrusion casting pouring system for an aluminum alloy balanced suspension large support, 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, 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 an annular material cake, the second chamber and the fourth chamber are used for a second contoured inner wall corresponding to the shape of the aluminum alloy balanced suspension large support, the upper mold is provided with a flow channel for realizing the connection between 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, and the second chamber is provided with a local extrusion pin.

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

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

[0011] In a preferred embodiment of the present invention, a center extruded pin cooling water pipe is coaxially fixedly connected inside the center extruded pin connecting rod, and the center extruded pin cooling water pipe is located and communicated with the center cavity of the center extruded pin.

[0012] The present invention also discloses a method for forming a large support of an aluminum alloy balanced suspension based on an extrusion casting pouring system. The filling volume is calculated according to the weight of aluminum liquid filled in the cavity; within an appropriate filling time, under the condition that the flow rate of the liquid rising port is not more than 50 cm / s, the diameter of the liquid rising port and the outer diameter of the small end of the center extrusion pin are determined; the extrusion volume required for the casting is calculated according to the volume of the casting; based on the required extrusion volume, the outer diameter of the annular cake and the extrusion stroke are calculated, wherein the outer diameter of the annular cake is equal to the outer diameter of the large end of the center extrusion pin and the inner diameter of the outer bushing of the center 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 feeding aluminum liquid volume, 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 feeding aluminum liquid volume, thereby determining the diameter and extrusion stroke of the local extrusion pin.

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

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

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

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

[0019] The present invention can effectively avoid the scale problem generated when the aluminum liquid is poured into the melting cup in the traditional process by accurately calculating and controlling the weight of the aluminum liquid filled in the cavity, the filling volume and the flow rate of the liquid riser, significantly reduce the slag inclusion defects inside the casting, and improve the internal quality of the casting. At the same time, since the melting cup needs to be rotated from an inclined state to a vertical state, the production cycle is greatly shortened and the production efficiency is improved.

[0020] The present invention effectively solves the technical problem of shrinkage and looseness in thick and large parts of castings by setting local shrinkage-feeding bosses and rationally designing the size parameters of the bosses and the specifications of local extrusion pins according to the volume of shrinkage-feeding aluminum liquid, thereby ensuring the compactness and mechanical properties of the castings. In addition, the central extrusion pin and the local extrusion pins adopt a hollow structure design and cooperate with the water cooling system for circulation cooling, which not only prolongs the service life of key components, but also improves the stability and reliability of equipment operation.

[0021] During the process, the riser nozzle oil heating assembly is set to effectively preheat the riser nozzle, prevent premature solidification of aluminum liquid, and ensure the filling quality of the casting. The use of various bushings with matching designs ensures the precise guidance of moving parts, improves the controllability of the process and the dimensional accuracy of the casting. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0024] Figure 2 It is a schematic diagram after extrusion of an extrusion casting pouring system of an aluminum alloy balanced suspension large support according to an embodiment of the present invention;

[0025] Figure 3 1. It is a schematic diagram of a large support of a commercial vehicle heavy truck balancing suspension before extrusion according to an embodiment of the present invention;

[0026] Figure 4 1. It is a schematic diagram of a large support of a commercial vehicle heavy truck balance suspension after extrusion according to an embodiment of the present invention;

[0027] Figure 5 Schematic diagram of a large support for a commercial vehicle heavy truck balancing suspension according to an embodiment of the present invention;

[0028] Figure 6 It is a schematic diagram of a prior art squeeze casting device;

[0029] In the figure, 1-center extrusion pin connecting rod (connected to the equipment); 2-center extrusion pin outer bushing; 3-center extrusion pin; 4-center extrusion pin cooling water pipe; 5-upper mold; 6-ring-shaped cake; 7-lower mold; 8-liquid liter pipe mouth oil heating assembly; 9-liquid liter mouth sleeve; 10-liquid liter mouth; 11-casting; 12-casting local extrusion boss; 13-local extrusion pin; 14-local extrusion pin cooling water pipe; 15-local extrusion pin bushing. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] The present invention is further described in detail below in conjunction with specific embodiments. Figure 1-5 As shown, this embodiment is explained by taking the large support of the balanced suspension of a commercial vehicle heavy truck as an example. The support is a large-scale high-strength chassis structural part of a lightweight aluminum alloy for automobiles. The casting has an outline size of 690 mm in length × 635 mm in width × 390 mm in height, and a casting weight of 23.64 kg. The maximum wall thickness is 50 mm, and the main wall thickness is 10 mm.

[0032] The extrusion casting pouring system of the present invention mainly includes an upper mold 5 and a lower mold 7. The upper mold 5 is provided with a first cavity and a second cavity arranged in parallel and spaced apart, and the lower mold 7 is provided with a third cavity and a fourth cavity arranged in parallel and spaced apart. The first cavity is coaxially arranged with the third cavity, and the second cavity is coaxially arranged with the fourth cavity. The first cavity and the third cavity are provided with a first contoured inner wall corresponding to the shape of the annular material cake 6, and the second cavity and the fourth cavity 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 also provided with a flow channel for realizing the communication between the second cavity and the third cavity.

[0033] In the specific structural design, a central extrusion pin 3 is provided in the first chamber, a liquid lifting system is provided in the third chamber, and a local extrusion pin 14 is provided in the second chamber. The liquid lifting system is composed of a liquid lifting pipe mouth oil heating assembly 8, a liquid lifting mouth sleeve 9 and a liquid lifting mouth 10 coaxially arranged in the third chamber. A central extrusion pin outer bushing 2 is provided in the first chamber, on which a central extrusion pin connecting rod 1 is coaxially fixed, and a central extrusion pin 3 is coaxially fixed below the connecting rod. A central extrusion pin cooling water pipe 4 is coaxially fixed in the central extrusion pin connecting rod 1, and the water pipe is connected to the central cavity of the central extrusion pin 3.

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

[0035] First, the filling volume is calculated based on the weight of the aluminum liquid filled in the cavity. Within the appropriate filling time, under the condition that the flow rate of the liquid riser does not exceed 50cm / s, the diameter of the liquid riser 10 is calculated and determined, and this diameter also determines the outer diameter of the small end of the center extrusion pin 3. Subsequently, the required extrusion volume of the casting is calculated based on the volume of the casting; based on the required extrusion volume, the outer diameter of the annular cake (i.e., the outer diameter of the large end of the center extrusion pin 3 and the inner diameter of the outer bushing 2 of the center extrusion pin) and the required extrusion stroke (i.e., the length of the outer diameter of the small end of the center extrusion pin) are calculated.

[0036] In order to solve the shrinkage problem that may occur in thick and large parts of the casting, the present invention sets a local shrinkage feeding boss 12 on the casting body. According to the required shrinkage feeding aluminum liquid volume, the height and diameter of the boss are determined, and then the diameter and extrusion stroke of the local extrusion pin 13 are determined. Since the central extrusion pin 3 and the local extrusion pin 13 are both moving parts, the central extrusion pin outer bushing 2, the liquid riser sleeve 9 and the local extrusion pin bushing 15 are designed in a matching manner.

[0037] In the initial stage of production, considering that the mold is at room temperature, a liquid riser nozzle oil heating assembly 8 is set around the liquid riser to prevent the aluminum liquid from freezing. In the continuous production process, since the center extrusion pin and the local extrusion pin need to repeatedly contact the high-temperature aluminum liquid, in order to extend their service life and ensure smooth movement, both are designed with a hollow structure and are circulated and cooled through their respective cooling water pipes. Among them, the center extrusion pin is cooled by the center extrusion pin cooling water pipe 4, and the local extrusion pin is cooled by its dedicated cooling water pipe 14. In addition, in order to realize the connection between the center pin and the casting equipment, a center extrusion pin connecting rod is specially designed.

[0038] The pouring 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 liquid riser 10 can be calculated and determined based on the volume of aluminum liquid required to be filled in the mold cavity, under the condition that the flow rate of the liquid riser does not exceed 50cm / s. Calculation formula: Casting volume cm 3 : Casting weight g / density g / cm 3 ; Filling time: 3 to 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 center extrusion pin 3 can be calculated according to the required extrusion volume. Calculation formula: Extrusion volume / casting volume ≥ 6%; extrusion stroke = 1.0 ~ 1.3 liters liquid port diameter

[0041] 3. The volume of the local extrusion boss 12 of the casting can be calculated and determined according to the amount of aluminum liquid required for the local part of the casting. Calculation formula: local extrusion volume (local shrinkage boss volume) / aluminum liquid amount at the part to be fed ≥ 2, generally, the diameter / height of the shrinkage boss = 1 to 1.5.

[0042] It should be pointed out that the calculation formula disclosed herein does not belong to the prior art. This formula is an empirical formula, which has made a substantial contribution to the creativity of the invention.

[0043] Example 1: In this example, the casting is a large support for a commercial heavy truck balance suspension, with a casting size of 690 mm long × 635 mm wide × 390 mm high, a casting weight of 23.64 kg, a maximum wall thickness of 50 mm, and a main body wall thickness of 10 mm. After calculation, the volume of aluminum liquid filled in the mold cavity is 9456 cm 3 , filling time 6s, under the condition that the flow rate of the liquid riser is controlled at 45cm / s, the diameter of the liquid riser is calculated to be 67mm, and 70mm is actually selected. According to the volume of the casting, 9456cm 3 , the required extrusion volume is calculated to be 567.36cm3 , the extrusion stroke is set to 85mm, and the outer diameter of the annular cake is calculated to be 115.7mm. The actual diameter is 120mm, so the outer diameter of the large end of the center extrusion pin is 120mm, and the inner diameter of the outer bushing of the center extrusion pin is 120mm. A local shrinkage boss is set at the maximum wall thickness of the casting, with a height of 30mm and a diameter of 35mm. 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 balanced suspension large support, the casting size is 580mm long × 525mm wide × 320mm high, the casting weight is 18.36kg, the maximum wall thickness is 45mm, and the main body wall thickness is 8mm. After calculation, the volume of aluminum liquid filled in the cavity is 7344cm 3 The filling time is 6s. When the flow rate of the liquid riser is controlled at 42cm / s, the diameter of the liquid riser is calculated to be 60.9mm. The actual diameter is 60mm. The volume of the casting is 7344cm 3 , the required extrusion volume is calculated to be 440.64cm 3 , the extrusion stroke is set to 75mm, and the outer diameter of the annular cake is calculated to be 105.3mm. The actual diameter is 110mm, so the outer diameter of the large end of the center extrusion pin is 110mm, and the inner diameter of the outer bushing of the center extrusion pin is 110mm. A local shrinkage boss is set at the maximum wall thickness of the casting, with a height of 28mm and a diameter of 32mm. The corresponding local extrusion pin diameter is 32mm and the extrusion stroke is 28mm.

[0045] Example 3: In this example, the casting is a large lightweight balanced suspension support, with dimensions of 520 mm in length × 460 mm in width × 280 mm in height, a weight of 15.42 kg, a maximum wall thickness of 40 mm, and a main body wall thickness of 7 mm. After calculation, the volume of aluminum liquid filled in the mold cavity is 6168 cm 3 The filling time is 5s. When the flow rate of the liquid riser is controlled at 40cm / s, the diameter of the liquid riser is calculated to be 62.6mm. The actual diameter is 65mm. The volume of the casting is 6168cm 3 , the required extrusion volume is calculated to be 370.08cm 3 , the extrusion stroke is set to 70mm, and the outer diameter of the annular cake is calculated to be 104.6mm. The actual diameter is 105mm, so the outer diameter of the large end of the center extrusion pin is 105mm, and the inner diameter of the outer bushing of the center extrusion pin is 105mm. A local shrinkage boss is set at the maximum wall thickness of the casting, with a height of 26mm and a diameter of 30mm. The corresponding local extrusion pin diameter is 30mm and the extrusion stroke is 26mm.

[0046] It can be concluded from the above three embodiments that the extrusion casting pouring system of the present invention can be flexibly adapted to the large balance suspension supports of different specifications. By adjusting various key parameters, such as the diameter of the liquid riser, the size of the center extrusion pin, the parameters of the local shrinkage boss, etc., the production requirements of castings of different sizes and weights can be met while ensuring the quality and production efficiency of the castings. Practice has proved that the castings produced by the process method of the present invention have dense internal structures, no obvious shrinkage defects, good mechanical properties, and fully meet the use requirements.

[0047] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present 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 only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0049] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. An extrusion casting pouring system for an aluminum alloy balanced suspension large support, comprising an upper mold (5) and a lower mold (7), characterized in that: The upper die (5) is provided with a first cavity and a second cavity which are arranged in parallel and spaced apart, and the lower die (7) is provided with a third cavity and a fourth cavity which are arranged in parallel and spaced apart, the first cavity and the third cavity are arranged coaxially, the second cavity and the fourth cavity are arranged coaxially, the first cavity and the third cavity are provided with a first contoured inner wall corresponding to the shape of the annular material cake (6), the second cavity and the fourth cavity are used for a second contoured inner wall corresponding to the shape of a large support of an aluminum alloy balanced suspension, the upper die (5) is provided with a flow channel for realizing the connection between the second cavity and the third cavity, the first cavity is provided with a central extrusion pin (3), the third cavity is provided with a liquid lifting system, and the second cavity is provided with a local extrusion pin (14).

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

3. The extrusion casting pouring system of the aluminum alloy balanced suspension large support according to claim 1 is characterized in that: A center extrusion pin outer bushing (2) is arranged in the first chamber, a center extrusion pin connecting rod (1) is coaxially fixedly connected to the center extrusion pin outer bushing (2), and a center extrusion pin (3) is coaxially fixedly connected below the center extrusion pin connecting rod (1).

4. The extrusion casting pouring system of the aluminum alloy balanced suspension large support according to claim 3 is characterized in that: A central extrusion pin cooling water pipe (4) is coaxially fixedly connected inside the central extrusion pin connecting rod (1), and the central extrusion pin cooling water pipe (4) is located in communication with the central cavity of the central extrusion pin (3).

5. A method for forming an aluminum alloy balanced suspension large support based on the extrusion casting pouring system according to any one of claims 1 to 4, characterized in that: The filling volume is calculated according to the weight of the aluminum liquid filled in the cavity; within an appropriate filling time, under the condition that the flow rate of the liquid riser is not more than 50cm / s, the diameter of the liquid riser, that is, the outer diameter of the small end of the center extrusion pin, is determined; the extrusion volume required for the casting is calculated according to the volume of the casting; based on the required extrusion volume, the outer diameter of the annular cake and the extrusion stroke are calculated, wherein the outer diameter of the annular cake is equal to the outer diameter of the large end of the center extrusion pin and the inner diameter of the outer bushing of the center extrusion pin.

6. The method for forming an aluminum alloy balanced suspension large support according to claim 5, characterized in that: 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 the molten aluminum for feeding, thereby determining the diameter and extrusion stroke of the local extrusion pin.

7. The method for forming an aluminum alloy balanced suspension large support according to claim 5, characterized in that: 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 the molten aluminum for feeding, thereby determining the diameter and extrusion stroke of the local extrusion pin.

8. The method for forming an aluminum alloy balanced suspension large support according to claim 5, characterized in that: The central extrusion pin and the local extrusion pin are respectively provided with matching central extrusion pin outer bushings, liquid riser sleeves and local extrusion pin bushings.

9. The method for forming an aluminum alloy balanced suspension large support according to claim 5, characterized in that: An oil heating assembly for the liquid riser is arranged around the periphery of the liquid riser to increase the temperature of the liquid riser to prevent the aluminum liquid from freezing; the center extrusion pin is designed to be a hollow structure, and the inner cavity of the center extrusion pin is cooled by circulating water through the center extrusion pin cooling water pipe; A center extrusion pin connecting rod is provided for connecting the center extrusion pin with the casting equipment.

10. The method for forming an aluminum alloy balanced suspension large support according to claim 5, characterized in that: The local extrusion pin is designed to be a hollow structure, and water circulation cooling is performed on the inner cavity of the local extrusion pin through a local extrusion pin cooling water pipe.

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