3D printing sand core for casting exhaust pipe

Abstract

The utility model relates to the technical field of exhaust pipe casting, in particular to a 3D printing sand core for exhaust pipe casting, which comprises an upper shell core, a middle shell core and a lower shell core from top to bottom, an upper air passage core is arranged between the upper shell core and the middle shell core, and a lower air passage core is arranged between the middle shell core and the lower shell core. A first connecting device is arranged between the upper air channel core and the lower air channel core, a second connecting device is arranged among the upper shell core, the middle shell core and the lower shell core, the sand core is manufactured in a 3D printing mode, the problems that in the research and development stage, products are not shaped, and the investment cost is high are solved, the manufacturing period is short, and the sand core complex in structure and large in size can be manufactured according to needs; the sand box is not limited by the height of a traditional sand box, the shell core is manufactured into three sections, the disassembled shell core and the air channel core can be installed layer by layer, the structure of the single shell core and the single air channel core is simplified, independent printing is easier, internal defects are few, and debugging is easy in the installation process.

Description

Technical Field

[0001] The utility model relates to the technical field of exhaust pipe casting, in particular to a 3D printed sand core for exhaust pipe casting. Background Art

[0002] There are many types of automobile engines, including gasoline engines, diesel engines, natural gas engines, etc., and there are various models of automobile engines, and there are many corresponding exhaust pipe models. When a new engine model is developed, it is often necessary to manufacture the corresponding exhaust pipe model. Therefore, the exhaust pipe is required to have high manufacturing efficiency and diverse structures.

[0003] In order to quickly obtain a sand core, technicians in this field use 3D printing sand cores to quickly obtain a designed sand mold. This application uses 3D printing sand core technology to obtain a 3D printed sand core for exhaust pipe casting. Utility Model Content

[0004] The purpose of the utility model is to overcome the deficiencies in the prior art and provide a 3D printed sand core for exhaust pipe casting that can obtain a large-sized sand core and has a high yield.

[0005] The utility model is realized through the following technical scheme: a 3D printed sand core for exhaust pipe casting, comprising an upper shell core, a middle shell core and a lower shell core from top to bottom, an upper airway core is arranged between the upper shell core and the middle shell core, a lower airway core is arranged between the middle shell core and the lower shell core, a connecting device 1 is arranged between the upper airway core and the lower airway core, and a connecting device 2 is arranged between the upper shell core, the middle shell core and the lower shell core.

[0006] Furthermore, the upper airway core and the lower airway core are hollow structures.

[0007] Furthermore, the first connecting device comprises an adhesive layer arranged between the upper airway core and the lower airway core.

[0008] Furthermore, grooves matching with the adhesive layer are arranged on the connection surfaces of the upper airway core and the lower airway core.

[0009] Furthermore, a coating layer is disposed outside the upper airway core and the lower airway core.

[0010] Furthermore, the second connecting device comprises a plurality of groups of connecting holes arranged at corresponding positions of the upper shell core, the middle shell core and the lower shell core, and connecting columns are arranged between any group of connecting holes.

[0011] Furthermore, the outer walls of the upper shell core, the middle shell core and the lower shell core are all provided with a hoisting structure.

[0012] Furthermore, the hoisting structure includes hoisting openings arranged on the outer walls of the upper shell core, the middle shell core, and the lower shell core.

[0013] The beneficial effects of the utility model are:

[0014] 1. The sand core is manufactured by 3D printing, which solves the problem of high investment cost of unfixed products in the R&D stage. The production cycle is short, and sand cores with complex structures and large sizes can be manufactured as needed, without being restricted by the height of traditional sand boxes.

[0015] 2. The shell core is made into three sections, so that the decomposed shell core and airway core can be installed layer by layer. The structure of a single shell core and airway core is simplified, which makes it easier to print separately, with fewer internal defects and easy debugging during installation;

[0016] 3. A connecting device 1 is provided between the upper airway core and the lower airway core, and a connecting device 2 is provided between the upper shell core, the middle shell core and the lower shell core, which are connected respectively, so as to better control the mold cavity and obtain a casting blank that meets the requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a disassembly diagram of Example 1;

[0018] Figure 2 It is a schematic diagram of the structure of the other side of the middle shell core;

[0019] Figure 3 Schematic diagram of the lower airway core structure.

[0020] 1. Upper shell core; 2. Middle shell core; 3. Lower shell core; 4. Upper airway core; 5. Lower airway core; 6. Lifting port; 7. Connecting hole; 8. Cavity; 9. Groove; 10. Upper chiller placement slot; 11. Straight runner; 12. Lower chiller placement slot; 13. Lower filter placement slot; 14. Horizontal runner; 15. Runner mouth. DETAILED DESCRIPTION

[0021] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" 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 indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] The following will be combined with the drawings in the utility model embodiments to clearly and completely describe the technical solutions in the utility model embodiments. Obviously, the described embodiments are only part of the utility model embodiments, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] Example 1

[0024] like Figure 1-3 As shown, a 3D printed sand core for exhaust pipe casting includes an upper shell core 1, a middle shell core 2, and a lower shell core 3 from top to bottom. An upper airway core 4 is installed between the upper shell core 1 and the middle shell core 2, and a lower airway core 5 is installed between the middle shell core 2 and the lower shell core 3. The upper shell core 1, the middle shell core 2, the lower shell core 3, the upper airway core 4, and the lower airway core 5 are 3D printed and manufactured separately, and then assembled together. The structure of a single shell core and an airway core is simplified, which is easier to print separately, has fewer internal defects, and is easy to debug during installation. The upper airway core 4 and the lower airway core 5 are 3D printed into a hollow structure with a designed wall thickness to ensure structural strength. The hollow structure can release thermal expansion stress inward and reduce the gas emission of the sand core, thereby ensuring that the wall thickness of the exhaust pipe after molding is stable to avoid holding air and air hole defects. The upper shell core 1, the middle shell core 2, and the lower shell core 3 are formed with the upper airway core 4 and the lower airway core 5. The cavity that matches the airway core 5 is provided with a connecting device 1 between the upper airway core 4 and the lower airway core 5 to ensure the connection stability. The connecting device 1 includes an adhesive layer installed between the upper airway core 4 and the lower airway core 5. The adhesive layer is made of K2 type glue, which dries quickly, is resistant to high temperature and chemical corrosion, and a groove 9 matching the adhesive layer is integrally formed on the connecting surface of the upper airway core 4 and the lower airway core 5. The adhesive layer is coated along the groove 9 with high precision, thereby improving the connection stability of the upper airway core 4 and the lower airway core 5. The upper airway core 4 and the lower airway core 5 can also be positioned by positioning pins and convex-concave matching to improve the positioning accuracy. A coating layer is sprayed on the outside of the upper airway core 4 and the lower airway core 5. Specifically, SLD-8854 is selected, which has a fast curing speed, thereby improving the surface quality of the upper airway core 4 and the lower airway core 5 and improving the thermal stability.

[0025] A second connecting device is installed between the upper shell core 1, the middle shell core 2, and the lower shell core 3. The second connecting device includes a plurality of groups of connecting holes 7 reserved at corresponding positions of the upper shell core 1, the middle shell core 2, and the lower shell core 3. A connecting column is installed between any group of connecting holes 7. The two ends of the connecting column extend to the outside of the shell core and are threaded. They can also be directly obtained by cutting from threaded rods, and then the upper shell core 1, the middle shell core 2, and the lower shell core 3 that are assembled together are fixed by nuts, or the upper shell core 1, the middle shell core 2, and the lower shell core 3 can be fixed together by external fixing parts such as pressure plates and mechanical arms. The installation is convenient, and the outer walls of the upper shell core 1, the middle shell core 2, and the lower shell core 3 are all processed with lifting structures. In this embodiment, the lifting structure includes a lifting port 6 reserved on the outer walls of the upper shell core 1, the middle shell core 2, and the lower shell core 3, and then the upper shell core 1, the middle shell core 2, and the lower shell core 3 are lifted by lifting devices such as hooks, claws, and mechanical arms.

[0026] A sprue 11 and a runner 14 are formed between the upper shell core 1, the middle shell core 2, and the lower shell core 3. An upper filter placement groove and a bottom filter placement groove 13 are reserved between the sprue 11 and the runner 14, and the corresponding upper filter and bottom filter are placed thereon. A lower chiller placement groove 12 is formed on the lower shell core 3, and the lower chiller is placed thereon. An upper chiller placement groove 10 is formed on the middle shell core 2, and the upper chiller is placed thereon. A runner mouth 15 is reserved on the upper shell core 1, and a pouring cup is placed thereon. A riser is also reserved on the upper shell core 1.

[0027] The production steps are as follows:

[0028] 1. Design the shape. According to the parameters of the exhaust pipe to be manufactured, design the shapes of the upper shell core 1, the middle shell core 2, the lower shell core 3, the upper airway core 4, and the lower airway core 5, and input them into the 3D printer;

[0029] 2. 3D printing, printing by a 3D printer, solidifying for 3-4 hours after 3D printing, cleaning the sand, and obtaining an upper shell core 1, a middle shell core 2, a lower shell core 3, an upper airway core 4, and a lower airway core 5;

[0030] 3. Surface treatment: spray alcohol-grade paint on the surface of the upper shell core 1, the middle shell core 2, and the lower shell core 3 to form a uniform, smooth, and beautiful coating film on the surface of the casting mold. The upper shell core 1, the middle shell core 2, and the lower shell core 3 are solidified, and a coating layer is sprayed on the outer surface of the upper airway core 4 and the lower airway core 5, thereby improving the surface quality of the upper airway core 4 and the lower airway core 5 and improving the thermal stability;

[0031] 4. Curing: heating and curing the surface-treated upper shell core 1, middle shell core 2, lower shell core 3, upper airway core 4, and lower airway core 5 to obtain the upper shell core 1, middle shell core 2, lower shell core 3, upper airway core 4, and lower airway core 5 to be assembled;

[0032] 5. Assemble, fix the lower shell core 3 on the platform, then place the lower airway core 5, the bottom filter, the lower chiller, and then install the connecting column, install the middle shell core 2 through the connecting column, and then place the upper airway core 4. Install a bonding layer between the upper airway core 4 and the lower airway core 5. The bonding layer should not be too much to avoid being squeezed out and falling into the mold after matching. Place the upper filter and the upper chiller, and finally install the upper shell core 1 through the connecting column, fix it with a nut, and then install the pouring cup at the pouring gate 15. A cavity is formed between the cavity and the upper airway core 4 and the lower airway core 5. During the installation process, adjust the position to make the upper shell core 1, the middle shell core 2, the lower shell core 3, the upper airway core 4, and the lower airway core 5 match well.

[0033] 6. Pour the molten liquid and inspect the quality of the exhaust pipe after molding.

[0034] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A 3D printed sand core for exhaust pipe casting, characterized in that: From top to bottom, it includes an upper shell core, a middle shell core, and a lower shell core. An upper airway core is arranged between the upper shell core and the middle shell core, a lower airway core is arranged between the middle shell core and the lower shell core, a connecting device 1 is arranged between the upper airway core and the lower airway core, and a connecting device 2 is arranged between the upper shell core, the middle shell core, and the lower shell core.

2. The 3D printed sand core for exhaust pipe casting according to claim 1, characterized in that: The upper airway core and the lower airway core are hollow structures.

3. The 3D printed sand core for exhaust pipe casting according to claim 1, characterized in that: The connecting device 1 includes an adhesive layer arranged between the upper airway core and the lower airway core.

4. The 3D printed sand core for exhaust pipe casting according to claim 3, characterized in that: The connecting surfaces of the upper airway core and the lower airway core are provided with grooves matching with the adhesive layer.

5. The 3D printed sand core for exhaust pipe casting according to claim 1, characterized in that: The upper airway core and the lower airway core are provided with a coating layer outside.

6. The 3D printed sand core for exhaust pipe casting according to claim 1, characterized in that: The second connecting device comprises a plurality of groups of connecting holes arranged at corresponding positions of the upper shell core, the middle shell core and the lower shell core, and connecting columns are arranged between any group of connecting holes.

7. The 3D printed sand core for exhaust pipe casting according to claim 1, characterized in that: The outer walls of the upper shell core, the middle shell core and the lower shell core are all provided with a hoisting structure.

8. The 3D printed sand core for exhaust pipe casting according to claim 7, characterized in that: The hoisting structure comprises hoisting openings arranged on the outer walls of the upper shell core, the middle shell core and the lower shell core.

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