A sand core and pouring system for casting a shell formation

Abstract

The application discloses a kind of sand core and pouring system for casting shell forming, it is related to casting technical field, including two groups of sand core structure, two shell molds are provided on each group of sand core structure;At least three sand core positioning structures are formed after the first sand core is inserted into the second sand core, and the sand core positioning structure is used to fix the relative position between the first sand core and the second sand core.The application increases the sand core positioning point through the side-by-side sand core scheme, and the sand core will not rotate.Improve the verticality of group core, and it is not easy to occur over-grouping;The application can simultaneously realize pouring to four shell molds by cooperating one pouring assembly, two groups of sand core structures and four shell molds, thereby improving work efficiency;Through the passage setting of pouring assembly, the flow distribution can be adjusted by changing the cross-sectional area and position of flow channel, so that four shell molds can be poured uniformly, sand flushing can be avoided, and product quality can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of casting, in particular to a sand core and a pouring system for forming a cast shell. BACKGROUND

[0002] Casting, especially sand casting, is a traditional and cost-effective method for manufacturing complex geometric metal shells (such as engine cylinder blocks, gearbox housings, pump valve housings, hydraulic valve blocks, etc.).

[0003] Sand cores are materials used to manufacture cores in casting production, composed of casting sand, sand binder, etc. In order to produce a product with high quality requirements and to speed up the production, the casting forming process is generally used at present. Therefore, the sand core and the pouring system are two core supporting technologies for realizing the successful casting of such shells, and their development and challenges constitute an important background.

[0004] As shown in Figure 10 The existing cast shell sand core structure is composed of two sand cores, with a sand core positioning structure in the middle for fixing the relative position between the two sand cores. Disadvantages: sand core 1 is prone to position rotation relative to sand core 2; the perpendicularity of sand core 1 and sand core 2 is poor; the sand core 1 and sand core 2 are prone to over-assembly, resulting in poor product quality. And it can only cast and form one product at a time, and cannot simultaneously pour and form multiple products; resulting in low efficiency. SUMMARY

[0005] The purpose of the present application is to provide a sand core and a pouring system for forming a cast shell, which solves the technical problems of poor product quality and low work efficiency of the existing technology.

[0006] The purpose of the present application can be achieved by the following technical solutions:

[0007] A pouring system for forming a cast shell, comprising two groups of sand core structures, each group of sand core structures being provided with two shell molds;

[0008] Each group of sand core structures comprises 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 core is connected to each other; the first sand core inserted into the second sand core forms at least three sand core positioning structures, which are used to fix the relative position between the first sand core and the second sand core.

[0009] As a further solution of the present application: the first sand core inserted into the second sand core forms two first sand core positioning points, and the first connecting sand core on the first sand core inserted into the second sand core forms a second sand core positioning point.

[0010] As a further scheme of the present application: one end of the two side-by-side first sand cores is connected by a third connecting sand core;

[0011] One end of the two side-by-side second sand cores is connected by a second connecting sand core.

[0012] As a further scheme of the present application: the first sand core and the second sand core are coaxially arranged.

[0013] As a further scheme of the present application: the inner wall of the two ports of the shell mold is provided with a chill.

[0014] As a further scheme of the present application: further comprising a pouring assembly arranged between the two groups of sand core structures:

[0015] The pouring assembly comprises two filters and a pouring channel arranged between the two filters;

[0016] The non-adjacent sides of the two filters are provided with a delivery channel, one end of the delivery channel is communicated with a right-angle diffusion channel, the right-angle diffusion channel is connected with a dispersion channel, and one side of the dispersion channel is communicated with two branch channels.

[0017] The branch channel is connected with an air outlet pipe, and the air outlet pipe is provided with a third branch sprue communicated with one port of the shell mold.

[0018] As a further scheme of the present application: the delivery channel is provided with a first riser, the first riser is provided with a first branch sprue, and the first branch sprue is communicated with the other port of the shell mold.

[0019] As a further scheme of the present application: the dispersion channel is provided with a second riser, the second riser is provided with at least two second branch sprues, and the second branch sprues are communicated with one side of the outer circumferential surface of the shell mold.

[0020] As a further scheme of the present application: the right-angle diffusion channel is further provided with two bottom channels in a symmetrical manner, the bottom channels are provided with fourth branch sprues communicated with the bottom port of the shell mold.

[0021] As a further scheme of the present application: the cross-sectional area of the delivery channel is larger than the cross-sectional area of the first branch sprue; and the cross-sectional area of the bottom channel is larger than the cross-sectional area of the dispersion channel.

[0022] As a further scheme of the present application: the delivery channel is arranged at a 90-degree angle with the right-angle diffusion channel; the right-angle diffusion channel is arranged at a 90-degree angle with the bottom channel; and the dispersion channel is arranged at a 90-degree angle with the second branch sprue and the third branch sprue.

[0023] The present application has the following beneficial effects:

[0024] The present application increases the sand core positioning points through the side-by-side sand core scheme, and the sand core does not rotate.

[0025] The present application can simultaneously realize pouring of the four shell molds through cooperation of one pouring assembly, two sets of sand core structures and four shell molds, improves work efficiency; through the channel setting of the pouring assembly, the flow distribution can be adjusted by changing the flow passage cross-sectional area and position, the four shell molds can be uniformly poured, sand flushing is avoided, and product quality is improved. BRIEF DESCRIPTION OF DRAWINGS

[0026] The present application will be further described below with reference to the drawings.

[0027] Figure 1 is a schematic diagram of the overall structure of the present application;

[0028] Figure 2 is a schematic diagram of the overall structure of the present application after the shell mold is disassembled;

[0029] Figure 3 is a schematic diagram of the overall structure of the present application after disassembly;

[0030] Figure 4 is a schematic diagram of the overall structure of the sand core structure of the present application;

[0031] Figure 5 is a schematic diagram of the overall structure of the first sand core and the second sand core of the present application after disassembly;

[0032] Figure 6 is a schematic diagram of the overall structure of the present application after disassembly;

[0033] Figure 7 is a schematic diagram of the overall structure of the pouring assembly of the present application;

[0034] Figure 8 is a schematic diagram of the overall structure of the pouring assembly of the present application from another perspective;

[0035] Figure 9 is a schematic diagram of the overall structure of the pouring assembly of the present application from another perspective;

[0036] Figure 10 is a schematic diagram of the overall structure of the pouring assembly of the present application from another perspective;

[0037] 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, pouring assembly; 21, pouring channel; 22, filter; 23, conveying channel; 24, right-angle diffusion channel; 25, first riser; 251, first sub-runner; 26, diffusion channel; 27, second riser; 271, second sub-runner; 28, air outlet pipe; 281, third sub-runner; 29, bottom channel; 291, fourth sub-runner; 210, sub-channel; 3, shell mold; 31, chill; 32, hole. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0039] Embodiment 1

[0040] Please refer to Figures 1 to 6 The present application is a pouring system for forming a shell, which comprises two groups of sand core structures 1, each of which is provided with two shell molds 3, please refer to Figure 1 The two groups 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 cooperation with the pouring assembly 2 to simultaneously realize pouring forming of the four shell molds 3, complete four castings in a single pouring, shorten the production cycle, realize batch production, and have high efficiency; reduce the number of smelting (one batch of molten iron serves multiple molds), reduce unit energy consumption and carbon emissions, and are more energy-saving and environmentally friendly; the shell mold 3 is divided into an upper mold and a lower mold, cooperates with the sand core structure 1 to form a pouring cavity, and is used for simultaneously forming four shell structures.

[0041] Each of the sand core structures 1 comprises two first sand cores 11 and two second sand cores 12 arranged side by side, and one end of the two first sand cores 11 and the two second sand cores 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, which are used to fix the relative positions between the first sand core 11 and the second sand core 12. The traditional shell is combined by two sand cores, and a sand core positioning structure is arranged in the middle, which is used to fix the relative positions between the two sand cores. However, the traditional shell has the following disadvantages: the first sand core is prone to rotation relative to the second sand core; the perpendicularity of the first sand core and the second sand core is poor; the sand core combination of the first sand core and the second sand core is prone to over-combination; in the present scheme, the side-by-side sand core mode is adopted, and the sand core positioning points are increased, so that the sand core is not prone to rotation. The perpendicularity of the sand core combination is improved, and the over-combination is not prone to occur. Meanwhile, in the present scheme, the upper and lower sand core structures 1 are spliced together, and six positioning points actually exist, which can play a mutual limiting role, and four shell structures can be manufactured, and the quality and efficiency are improved.

[0042] In the present embodiment, referring to Figure 6 , 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 the present scheme, two sand core positioning points are increased by using the splicing mode based on the original structure of the first sand core 11 inserted into the second sand core 12, which is more convenient and simple in structure; meanwhile, the first connecting sand core 13 is used, which is connected to the inner wall of the two first sand cores 11 to fix the first sand core 11, and is inserted into the second sand core 12 to form a third sand core positioning point, thereby avoiding the rotation of the first sand core 11 and the second sand core 12.

[0043] Referring to Figure 4 , one end of the two side-by-side first sand cores 11 is connected by a third connecting sand core 15, and one end of the 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 the two side-by-side second sand cores 12 into a whole, it is not only beneficial to increase the sand core positioning points, but also convenient to install.

[0044] Referring to Figure 1 , Figure 3 and Figure 5 , wherein the upper die of the shell mold 3 is provided with a hole 32, and the second sand core 12 is provided with a limiting column 121, the hole 32 and the limiting column 121 are matched to fix and install the upper die.

[0045] The first sand core 11 and the second sand core 12 are coaxially arranged to improve the perpendicularity of the sand core combination and prevent over-combination.

[0046] Referring toFigure 3 As shown, the two-port inner wall of the shell mold 3 is provided with a chill 31. After the molten iron enters from the third runner 281, it first contacts the chill 31 and is cooled. The chill 31 is a metal block (usually made of cast iron, copper or steel) used to accelerate the cooling of the local area of the shell mold 3. It significantly accelerates the solidification speed of the casting at the contact position by rapidly absorbing heat.

[0047] Embodiment 2

[0048] Based on Embodiment 1, referring to Figures 7-9 As shown, it also includes a casting assembly 2 arranged between the two groups of sand core structures 1:

[0049] The casting assembly 2 includes two filters 22 and a casting channel 21 arranged between the two filters 22; the casting channel 21 is located at the center of the structure, with central inflow to ensure the symmetry of the initial flow; the purpose is to achieve uniform input of molten iron to the four shell molds 3;

[0050] The non-adjacent side of each of the two filters 22 is provided with a conveying channel 23, one end of the conveying channel 23 is communicated with a right-angle diffusion channel 24, the 90° buffer design reduces the flow rate and avoids air entrainment caused by molten iron impact, the right-angle diffusion channel 24 is connected with a dispersion channel 26, which splits a single stream into two paths to match the mold layout, and one side of the dispersion channel 26 is communicated with two sub-channels 210.

[0051] The sub-channels 210 are connected with an air outlet pipe 28 for discharging air during casting; thereby ensuring the casting quality of the shell, and the air outlet pipe 28 is provided with a third runner 281, which is communicated with one port of the shell mold 3.

[0052] The conveying channel 23 is provided with a first riser 25, and the first riser 25 is provided with a first runner 251, which is communicated with the other port of the shell mold 3.

[0053] The molten iron is injected through the pouring port on the casting channel 21, filtered through the filter 22, and then input to the conveying channel 23 on both sides, and then sequentially passes through the right-angle diffusion channel 24 and the dispersion channel 26, and then is input to the sub-channel 210. The above-mentioned channels are arranged to cooperate with the pouring of the four shell molds 3, so that the molten iron is uniformly poured into the mold, ensuring the casting quality of the shell.

[0054] In the embodiment, the dispersion channel 26 is provided with a second riser 27, and the second riser 27 is provided with at least two second sub-gates 271, which are communicated with the outer peripheral side of the shell mold 3. The right-angle diffusion channel 24 is also provided with two bottom channels 29, and the bottom channels 29 are provided with fourth sub-gates 291, which are communicated with the bottom port of the shell mold 3. The cross-sectional area of the delivery channel 23 is twice larger than that of the first sub-gate 251, and the cross-sectional area of the bottom channel 29 is larger than that of the dispersion channel 26. The cross-sectional area of the delivery channel 23 is enlarged, so as to avoid that the molten iron enters the cavity from the first sub-gate 251 first, and causes sand hole defects, and also avoid that the shell surface after solidification has sand hole defects. The flow distribution is adjusted by adjusting the cross-sectional area and position of the flow channel, so that the molten iron enters the shell mold 3 uniformly. At this time, the molten iron enters the cavity from the fourth sub-gate 291 at the bottom, the second sub-gate 271 and the third sub-gate 281 at the side, and the speed is controlled to be less than 60 cm / s. When the molten iron enters the cavity from both ends, the molten iron will first contact the cold iron 31 and be cooled, and the shell is formed.

[0055] In the scheme, the riser is located above the gate. When the molten iron is insufficient, the molten iron can be supplemented into the shell mold 3 through the riser. Through the above structure, the first sub-gate 251 pours from the top to the port of the shell mold 3, 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 the other port. The overall design can realize uniform pouring into the shell mold 3. The difference is reduced, sanding is avoided, and the product quality is improved. At the same time, one casting assembly 2 cooperates with four shell molds 3, and the pouring efficiency is improved.

[0056] Referring to Figure 9 As shown in the figure, the delivery channel 23 is arranged at a 90-degree angle with the right-angle diffusion channel 24. The right-angle diffusion channel 24 is arranged at a 90-degree angle with the bottom channel 29. The dispersion channel 26 is arranged at a 90-degree angle with the second sub-gate 271 and the third sub-gate 281. Before entering the cavity, the flow channel changes direction by 90 degrees multiple times and the cross-sectional area changes, so as to avoid that the molten iron directly rushes into the cavity of the casting, and the flow rate is reduced.

[0057] The above describes one embodiment of the application in detail, but the content described is only a preferred embodiment of the application, and cannot be considered as limiting the implementation range of the application. Any equivalent changes and improvements made according to the application scope should still belong to the patent scope covered by the application.

Claims

1. A gating system for shell molding of castings, characterized in that, It comprises two groups of sand core structures (1), 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 two second sand cores (12) arranged side by side, and one end of the two first sand cores (11) and the two second sand cores (12) is connected to each other; at least three sand core positioning structures are formed after the first sand core (11) is inserted into the second sand core (12), and the sand core positioning structures are used for fixing the relative position between the first sand core (11) and the second sand core (12); It also comprises a pouring assembly (2) arranged between the two groups of sand core structures (1): The pouring assembly (2) comprises two filters (22) and a pouring channel (21) arranged between the two filters (22); The non-adjacent side of each of the two filters (22) is provided with a conveying channel (23), one end of the conveying channel (23) is communicated with a right-angle diffusion channel (24), the right-angle diffusion channel (24) is connected with a dispersion channel (26), and one side of the dispersion channel (26) is communicated with two branch channels (210); Two bottom channels (29) are also symmetrically arranged on the right-angle diffusion channel (24), a fourth branch gate (291) is arranged on the bottom channel (29), and the fourth branch gate (291) is communicated with a bottom port of the shell mold (3); The cross-sectional area of the conveying channel (23) is larger than the cross-sectional area of the first branch 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 conveying channel (23) and the right-angle diffusion channel (24) are arranged at an angle of 90 degrees, the right-angle diffusion channel (24) and the bottom channel (29) are arranged at an angle of 90 degrees, and the dispersion channel (26) and the second branch gate (271) and the third branch gate (281) are arranged at an angle of 90 degrees; The distribution of flow is adjusted by adjusting the cross-sectional area and position of the flow channel, so that the molten iron uniformly enters the shell mold (3).

2. A gating system for shell molding according to claim 1, characterized in that Two first sand core positioning points (16) are formed on the second sand core (12) after the first sand core (11) is inserted into the second sand core (12), and a second sand core positioning point (17) is formed on the second sand core (12) after the first connecting sand core (13) on the first sand core (11) is inserted into the second sand core (12).

3. A gating system for shell molding according to claim 1, wherein One end of the two first sand cores (11) arranged side by side is connected through a third connecting sand core (15). One end of the two second sand cores (12) arranged side by side is connected through a second connecting sand core (14).

4. A gating system for shell molding according to claim 1, wherein The first sand core (11) and the second sand core (12) are coaxially arranged.

5. A gating system for shell molding according to claim 1, wherein Cold irons (31) are arranged on the inner walls of the two ports of the shell mold (3).

6. A gating system for shell molding according to claim 1, wherein An air outlet pipe (28) is connected to the branch channel (210), a third branch gate (281) is arranged on the air outlet pipe (28), and the third branch gate (281) is communicated with one port of the shell mold (3).

7. A gating system for shell molding according to claim 6, characterized in that A first riser (25) is arranged on the conveying channel (23), a first branch gate (251) is arranged on the first riser (25), and the first branch gate (251) is communicated with the other port of the shell mold (3).

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