Sand core and pouring system for casting shell molding

Abstract

The invention discloses a sand core and pouring system for casting shell forming, and relates to the technical field of casting, the sand core and pouring system comprises two sand core structures, and each sand core structure is provided with two shell molds; after the first sand core is inserted into the second sand core, at least three sand core positioning structures are formed, and the sand core positioning structures are used for fixing the relative position between the first sand core and the second sand core. According to the scheme that the sand cores are arranged side by side, sand core positioning points are increased, and the sand cores cannot rotate. The core assembly perpendicularity is improved, and the over-assembly condition is not prone to occurring; the casting assembly, the two groups of sand core structures and the four shell molds are matched, so that the four shell molds can be synchronously cast, and the working efficiency is improved; through the arrangement of the channels of the casting assembly, flow distribution is adjusted by changing the sectional area and the position of the flow channel, the interiors of the four shell molds can be evenly cast, sand washing is avoided, and the product quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of casting, and in particular to a sand core and a pouring system for casting shell molding. Background Art

[0002] Casting, especially sand casting, is a traditional and cost-effective method for manufacturing metal housings with complex geometries, such as engine blocks, transmission housings, pump and valve housings, hydraulic valve blocks, etc.

[0003] Sand cores are the material used to create cores in foundry production and are composed of foundry sand, sand binder, and other components. To achieve high-quality products and accelerate production, a pouring process is currently commonly used. Therefore, sand cores and pouring systems are the two core technologies supporting the successful casting of such shells, and their development and challenges constitute a crucial background.

[0004] like Figure 10 As shown, the existing casting shell sand core structure consists of two sand cores, with a central sand core locating the two cores relative to each other. Disadvantages include: Sand core 1 is prone to rotation relative to sand core 2; sand cores 1 and 2 are not perpendicular to each other; and sand cores 1 and 2 are prone to over-interlacing, resulting in poor product quality. Furthermore, the casting process can only form one product at a time, not multiple products simultaneously, resulting in low efficiency. Summary of the Invention

[0005] The purpose of the present invention is to provide a sand core and pouring system for casting shell molding, so as to solve the following technical problems: the technical problems of poor product quality and low working efficiency of existing products.

[0006] The purpose of the present invention can be achieved through the following technical solutions: A sand core and pouring system for casting shell molding, comprising two sets of sand core structures, each set of sand core structures being provided with two shell molds; Each group of the sand core structures includes two first sand cores and a second sand core arranged side by side, and one end of the two first sand cores and the second sand cores are connected to each other; after the first sand core is inserted into the second sand core, at least three sand core positioning structures are formed, and the sand core positioning structures are used to fix the relative position between the first sand core and the second sand core.

[0007] As a further solution of the present invention: the first sand core is inserted into the second sand core to form two first sand core positioning points, and the first connecting sand core on the first sand core is inserted into the second sand core to form a second sand core positioning point.

[0008] As a further solution of the present invention: one end of two side-by-side first sand cores is connected by a third connecting sand core; One ends of the two side-by-side second sand cores are connected through a second connecting sand core.

[0009] As a further solution of the present invention: the first sand core and the second sand core are coaxially arranged.

[0010] As a further solution of the present invention: chills are provided on the inner walls of both ends of the shell mold.

[0011] As a further solution of the present invention, a casting assembly is further provided between the two sets of sand core structures: The casting assembly includes two filters and a casting channel arranged between the two filters; A delivery channel is provided on one side of the two filters that are not adjacent to each other, one end of the delivery channel is connected to a right-angle diffusion channel, the right-angle diffusion channel is connected to a dispersion channel, and one side of the dispersion channel is connected to two branch channels; The branch channel is connected to an air outlet pipe, the air outlet pipe is provided with a third branch gate, and the third branch gate is communicated with a port of the shell mold.

[0012] As a further solution of the present invention: a first riser is provided on the conveying channel, a first sub-gate is provided on the first riser, and the first sub-gate is communicated with another port of the shell mold.

[0013] As a further solution of the present invention: a second riser is provided on the dispersion channel, at least two second sub-gates are provided on the second riser, and the second sub-gates are communicated with one side of the outer peripheral surface of the shell mold.

[0014] As a further solution of the present invention: two bottom channels are symmetrically arranged on the right-angle diffusion channel, and a fourth sub-gate is provided on the bottom channel. The fourth sub-gate is connected to the bottom port of the shell mold.

[0015] As a further solution of the present invention: the cross-sectional area of ​​the conveying channel is larger than the cross-sectional area of ​​the first sub-gate; the cross-sectional area of ​​the bottom channel is larger than the cross-sectional area of ​​the dispersion channel.

[0016] As a further solution of the present invention: the conveying channel is set at a 90-degree angle to the right-angle diffusion channel; the right-angle diffusion channel is set at a 90-degree angle to the bottom channel; the dispersion channel is set at a 90-degree angle to the second sub-gate and the third sub-gate.

[0017] Beneficial effects of the present invention: The present invention adopts the side-by-side sand core solution to increase the sand core positioning points, so that the sand core will not rotate. It improves the verticality of the core assembly and is less likely to over-assemble. The present invention combines a casting component, two sets of sand core structures and four shell molds to simultaneously realize casting of the four shell molds, thereby improving work efficiency; through the channel setting of the casting component, the flow distribution is adjusted by changing the flow channel cross-sectional area and position, so that the interior of the four shell molds can be evenly cast, sand washing is avoided, and product quality is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below with reference to the accompanying drawings.

[0019] Figure 1 It is a schematic structural diagram of the present invention as a whole; Figure 2 This is a schematic diagram of the overall structure of the housing mold after disassembly of the present invention; Figure 3 It is a schematic diagram of the structure of the present invention after disassembly; Figure 4 1 is a schematic diagram of the overall structure of the sand core structure of the present invention; Figure 5 1 is a schematic diagram of the overall structure of the first sand core and the second sand core after being separated; Figure 6 It is a schematic structural diagram of the present invention; Figure 7 It is a schematic diagram of the overall structure of the casting assembly of the present invention; Figure 8 is a schematic structural diagram of the casting assembly of the present invention from another perspective; Figure 9 1 is a schematic diagram of the top view of the casting assembly of the present invention; Figure 10 It is a cross-sectional structural diagram of the sand core structure in the prior art.

[0020] In the figure: 1. Sand core structure; 11. First sand core; 12. Second sand core; 121. Limiting column; 13. First connecting sand core; 14. Second connecting sand core; 15. Third connecting sand core; 16. First sand core positioning point; 17. Second sand core positioning point; 2. Casting assembly; 21. Casting channel; 22. Filter; 23. Conveying channel; 24. Right-angle diffusion channel; 25. First riser; 251. First sub-gate; 26. Dispersion channel; 27. Second riser; 271. Second sub-gate; 28. Exhaust pipe; 281. Third sub-gate; 29. ​​Bottom channel; 291. Fourth sub-gate; 210. Sub-channel; 3. Shell mold; 31. Cold iron; 32. Hole. DETAILED DESCRIPTION

[0021] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0022] Example 1: See also Figures 1 to 6 As shown, the present invention is a sand core and pouring system for casting shell molding, including two groups of sand core structures 1, each group of sand core structures 1 is provided with two shell molds 3, see Figure 1 As shown, two sets of sand core structures 1 are spliced ​​together to limit the four shell molds 3 and ensure the mold position accuracy; and they are used in conjunction with the casting assembly 2 to simultaneously realize the casting and molding of the four shell molds 3, and complete four castings in a single casting, shortening the production cycle and realizing mass production with high efficiency; reducing the number of smelting times (one furnace of molten iron serves multiple molds), reducing unit energy consumption and carbon emissions, and being more energy-saving and environmentally friendly; the shell mold 3 is divided into an upper mold and a lower mold, which cooperates with the sand core structure 1 to form a casting cavity for simultaneously molding four shell structures.

[0023] Each set of sand core structures 1 includes two first sand cores 11 and a second sand core 12 arranged side by side, connected at one end. The insertion of the first sand core 11 into the second sand core 12 forms at least three sand core positioning structures, which secure the relative position between the first and second sand cores 11, 12. Conventional shells consist of two sand cores, with a central sand core positioning point securing the two cores. This approach suffers from the following drawbacks: core 1 is prone to rotation relative to core 2; core 1 and core 2 have poor verticality; and core 1 and core 2 are prone to over-coupling. This solution employs a side-by-side sand core arrangement, increasing the number of core positioning points and preventing core rotation. This improves core verticality and reduces over-coupling. Furthermore, by splicing the upper and lower sets of sand core structures 1 together, this solution creates six positioning points, which act as mutual restraints and allow the production of four shell structures, improving both quality and efficiency.

[0024] In this embodiment, see Figure 6As shown, the first sand core 11 is inserted into the second sand core 12 to form two first sand core positioning points 16, and the first connecting sand core 13 on the first sand core 11 is inserted into the second sand core 12 to form a second sand core positioning point 17. In this solution, the first sand core 11 is inserted into the second sand core 12 in the original structure, and two sand core positioning points are added by plugging. This is more convenient and has a simpler structure. At the same time, the first connecting sand core 13 is used. On the one hand, it connects from the inner walls of the two first sand cores 11 to fix the first sand core 11. On the other hand, it is inserted into the second sand core 12 to form a third sand core positioning point, preventing the first sand core 11 and the second sand core 12 from rotating.

[0025] See Figure 4 As shown, one end of two side-by-side first sand cores 11 is connected by a third connecting sand core 15; one end of two side-by-side second sand cores 12 is connected by a second connecting sand core 14. In order to connect the two side-by-side first sand cores 11 or second sand cores 12 into a whole, it is not only beneficial to increase the sand core positioning points, but also more convenient to install.

[0026] See Figure 1 、 Figure 3 and Figure 5 As shown, a hole 32 is provided on the upper mold of the shell mold 3, and a limiting column 121 is provided on the second sand core 12. The hole 32 cooperates with the limiting column 121 to fix the upper mold.

[0027] The first sand core 11 and the second sand core 12 are coaxially arranged to improve the verticality of the core assembly and prevent over-assembly.

[0028] See Figure 3 As shown, chills 31 are installed on the inner walls of both ends of the shell mold 3. After molten iron enters through the third sub-gate 281, it first contacts the chills 31 for cooling. The chills 31 are metal blocks (typically made of cast iron, copper, or steel) used to accelerate cooling in a localized area of ​​the shell mold 3. By rapidly absorbing heat, they significantly accelerate the solidification of the casting in the contact area.

[0029] Example 2: Based on Example 1, see Figure 7-Figure 9 As shown, it also includes a casting assembly 2 arranged between the two sets of sand core structures 1: The casting assembly 2 includes two filters 22 and a casting channel 21 disposed between the two filters 22; the casting channel 21 is located at the center of the structure, with central inflow to ensure initial flow symmetry; the purpose is to achieve uniform input of molten iron to the four shell molds 3; A conveying channel 23 is provided on each non-adjacent side of the two filters 22. One end of the conveying channel 23 is connected to a right-angle diffusion channel 24. The 90° buffer design reduces the flow rate and prevents molten iron from impacting and entraining air. The right-angle diffusion channel 24 is connected to a dispersion channel 26, which splits the single flow into two paths to match the mold layout. One side of the dispersion channel 26 is connected to two branch channels 210. The branch channel 210 is connected to an air outlet pipe 28 for discharging air during pouring, thereby ensuring the casting quality of the shell. The air outlet pipe 28 is provided with a third branch gate 281, and the third branch gate 281 is connected to a port of the shell mold 3.

[0030] The conveying channel 23 is provided with a first riser 25 , and the first riser 25 is provided with a first sub-gate 251 . The first sub-gate 251 is communicated with another port of the shell mold 3 .

[0031] Molten iron is poured through the pouring port on the casting channel 21, filtered by the filter 22, and then fed into the delivery channels 23 on both sides. It then passes through the right-angle diffusion channel 24 and the dispersion channel 26, and finally enters the branch channel 210. The arrangement of these channels is to coordinate the pouring of the four shell molds 3, uniformly pouring the molten iron into the molds, and ensuring the casting quality of the shell.

[0032] In this embodiment, the dispersion channel 26 is provided with a second riser 27, which is provided with at least two second sub-gates 271. The second sub-gates 271 are connected to one side of the outer peripheral surface of the shell mold 3. The right-angle diffusion channel 24 is also symmetrically provided with two bottom channels 29. The bottom channels 29 are provided with fourth sub-gates 291, which are connected to the bottom port of the shell mold 3. The cross-sectional area of ​​the conveying channel 23 is twice as large as the cross-sectional area of ​​the first sub-gate 251, and the cross-sectional area of ​​the bottom channel 29 is larger than the cross-sectional area of ​​the dispersion channel 26; the flow channel cross-sectional area of ​​the conveying channel 23 is enlarged to prevent the molten iron from entering the cavity from the first sub-gate 251 first, causing sand holes to be formed by sand blasting, and also to avoid defects such as sand holes on the surface of the shell after solidification. The flow distribution is adjusted by adjusting the flow channel cross-sectional area and position to make it enter the shell mold 3 evenly; at this time, the molten iron will first enter the cavity from the fourth sub-gate 291 on the bottom and the second sub-gate 271 and the third sub-gate 281 on the side, and the speed is controlled to be less than 60 cm / s. When the molten iron enters the cavity from both ends, it will first contact with the cold iron 31 for cooling and the shell is formed.

[0033] In this solution, the risers are all located above the pouring gate. When the molten iron is insufficient, the shell mold 3 can be supplemented with molten iron through the risers. Through the arrangement of the above structure, the first sub-gate 251 pours from the top to the port of the shell mold 3, while the fourth sub-gate 291 pours from the bottom, the second sub-gate 271 pours from the side, and the third sub-gate 281 pours from another port. The overall design can achieve uniform pouring into the shell mold 3, reduce the drop, avoid sand blasting, and improve product quality. At the same time, one casting assembly 2 cooperates with four shell molds 3 to improve the pouring efficiency.

[0034] See Figure 9 As shown, the conveying channel 23 is set at a 90-degree angle to the right-angle diffusion channel 24; the right-angle diffusion channel 24 is set at a 90-degree angle to the bottom channel 29; and the dispersion channel 26 is set at a 90-degree angle to both the second sub-gate 271 and the third sub-gate 281. Before entering the mold cavity, the flow channel undergoes multiple 90-degree changes and cross-sectional area variations, preventing molten iron from directly impacting the casting cavity and reducing flow velocity.

[0035] The above is a detailed description of an embodiment of the present invention. However, the content described is only a preferred embodiment of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A sand core and pouring system for casting shell molding, characterized in that: It comprises two groups of sand core structures (1), and each group of the sand core structures (1) is provided with two shell molds (3); Each group of the sand core structures (1) comprises two first sand cores (11) and a second sand core (12) arranged side by side, and one end of the two first sand cores (11) and the second sand core (12) are connected to each other; after the first sand core (11) is inserted into the second sand core (12), at least three sand core positioning structures are formed, and the sand core positioning structures are used to fix the relative position between the first sand core (11) and the second sand core (12).

2. A sand core and pouring system for casting shell molding according to claim 1, characterized in that: The first sand core (11) is inserted into the second sand core (12) to form two first sand core positioning points (16), and the first connecting sand core (13) on the first sand core (11) is inserted into the second sand core (12) to form a second sand core positioning point (17).

3. A sand core and pouring system for casting shell molding according to claim 1, characterized in that: One ends of two side-by-side first sand cores (11) are connected via a third connecting sand core (15); One ends of the two side-by-side second sand cores (12) are connected via a second connecting sand core (14).

4. A sand core and pouring system for casting shell molding according to claim 1, characterized in that: The first sand core (11) and the second sand core (12) are coaxially arranged.

5. The sand core and pouring system for casting shell molding according to claim 1, characterized in that: Chills (31) are provided on the inner walls of both ends of the shell mold (3).

6. A sand core and pouring system for casting shell molding according to claim 1, characterized in that: The invention also includes a casting assembly (2) disposed between the two sets of sand core structures (1): The casting assembly (2) comprises two filters (22) and a casting channel (21) arranged between the two filters (22); A delivery channel (23) is provided on one side of the two filters (22) that are not adjacent to each other. One end of the delivery channel (23) is connected to a right-angle diffusion channel (24). A dispersion channel (26) is connected to the right-angle diffusion channel (24). One side of the dispersion channel (26) is connected to two branch channels (210). The branch channel (210) is connected to an air outlet pipe (28), and the air outlet pipe (28) is provided with a third branch gate (281), and the third branch gate (281) is communicated with a port of the shell mold (3).

7. A sand core and pouring system for casting shell molding according to claim 6, characterized in that: A first riser (25) is provided on the conveying channel (23), a first sub-gate (251) is provided on the first riser (25), and the first sub-gate (251) is communicated with another port of the shell mold (3).

8. A sand core and pouring system for casting shell molding according to claim 7, characterized in that: A second riser (27) is provided on the dispersion channel (26), and at least two second sub-gates (271) are provided on the second riser (27), and the second sub-gates (271) are communicated with one side of the outer peripheral surface of the shell mold (3).

9. A sand core and pouring system for casting shell molding according to claim 8, characterized in that: Two bottom channels (29) are symmetrically arranged on the right-angle diffusion channel (24), and a fourth sub-gate (291) is arranged on the bottom channel (29), and the fourth sub-gate (291) is connected to the bottom port of the shell mold (3).

10. A sand core and pouring system for casting shell molding according to claim 9, characterized in that: The cross-sectional area of ​​the conveying channel (23) is larger than the cross-sectional area of ​​the first sub-gate (251), and the cross-sectional area of ​​the bottom channel (29) is larger than the cross-sectional area of ​​the dispersion channel (26).

11. A sand core and pouring system for casting shell molding according to claim 6, characterized in that: The conveying channel (23) is arranged at a 90-degree angle to the right-angle diffusion channel (24); the right-angle diffusion channel (24) is arranged at a 90-degree angle to the bottom channel (29); and the dispersion channel (26) is arranged at a 90-degree angle to the second sub-gate (271) and the third sub-gate (281).

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