A single crystal superalloy casting bottom gating system

Abstract

The utility model discloses a single crystal high temperature alloy casting bottom injection type pouring system, including sprue cup, casting wax mould, middle column pipe, bottom runner and bottom disc, the middle column pipe vertical installation in the middle part of bottom disc, the upper end of middle column pipe is connected with sprue cup through connecting wax mould, the connecting wax mould includes the filter screen installation cylinder section of upper part, the runner connection cylinder section of middle part and the plugging installation conical section of lower part, the diameter of runner connection cylinder section is less than the diameter of filter screen installation cylinder section, the lower end of casting wax mould is connected with bottom disc through the selector wax mould, and the upper end is connected with the upper end of sprue cup through the riser wax mould, and the upper end of bottom runner is connected with runner connection cylinder section, and the lower end is connected with the bottom of casting wax mould. The utility model discloses bottom injection type filling, and metal liquid slowly rises, and the partial core breakage caused by the impact pottery core is avoided.

Description

Technical Field

[0001] This utility model belongs to the field of single crystal investment casting technology, and in particular relates to a bottom-pouring gating system for single crystal high-temperature alloy castings. Background Technology

[0002] Currently, single-crystal high-temperature hollow castings typically employ a top-pouring gating system. When using this system, the molten metal directly impacts the ceramic core, which can easily lead to core misalignment or even core breakage. Furthermore, the molten metal directly washes against the inner wall of the mold shell, with impurities impacting the blades downwards, causing turbulence in the molten metal. This not only requires a long settling time but also easily generates grain defects. Summary of the Invention

[0003] The main objective of this invention is to provide a bottom-pouring casting system for single-crystal high-temperature alloy castings, aiming to solve at least one of the technical problems existing in the background art.

[0004] Therefore, the present invention provides a bottom-pouring casting system for single-crystal high-temperature alloy castings, comprising a pouring cup, a casting wax model, a central column, a bottom runner, and a base. The central column is vertically installed in the middle of the base. The upper end of the central column is connected to the pouring cup via a connecting wax model. The connecting wax model includes an upper cylindrical section for installing a filter screen, a middle cylindrical section for connecting the runner, and a lower conical section for installing a plug. The lower end of the casting wax model is connected to the base via a crystal selector wax model, and the upper end is connected to the upper end of the pouring cup via a riser wax model. The upper end of the bottom runner is connected to the cylindrical section for connecting the runner, and the lower end is connected to the bottom of the casting wax model.

[0005] Specifically, a partition plate is fixedly fitted on the central column tube near the position of the connecting wax mold, and a first boss is provided on the chassis between the central column tube and the casting wax mold.

[0006] Specifically, the partition plate is a plastic sheet.

[0007] Specifically, multiple wax molds of the casting are evenly arranged around the central column tube.

[0008] Specifically, the diameter of the cylindrical section connecting the gating channel is smaller than the diameter of the cylindrical section where the filter screen is installed.

[0009] Specifically, a second protrusion is provided around the outer perimeter of the chassis.

[0010] Compared with the prior art, the present invention has the following beneficial effects: When casting the mold shell prepared using the bottom-pouring gating system of this application, the molten metal rises slowly due to the bottom-pouring filling method, avoiding core breakage caused by impact on the ceramic core. Inclusions float to the riser with the molten metal and can be removed, reducing fluorescence defects. The steady rise of the molten metal is conducive to grain growth.

[0011] The lower part of the pouring cup is designed with a cylindrical section (the cylindrical section for installing the filter screen). After the mold shell is dewaxed, it will form a cylindrical cavity for installing the filter screen to filter out metal inclusions. The upper part of the central column tube is designed with a cylindrical section (the cylindrical section for connecting the sprue) + a cone (the cone section for installing the plug). The cylinder is used to arrange the starting position of the sprue along its circumference, and the cone is used to install the corundum plug before pouring to seal the central column tube. This can prevent the filling metal in the central column tube, reduce alloy waste, and lower pouring costs.

[0012] During mold assembly, a partition plate is installed at the lower part of the conical structure of the central column tube. No shell is formed on the partition plate. After the mold assembly is shelled, the central column tube sections above and below the partition plate can be separated. A ring of first bosses is set inside the crystallization base. The upper surface of this boss is not shelled. After the entire mold assembly is shelled and dewaxed, the inner and outer parts of the bosses can be separated. This allows the portion between the bosses and the partition plate to be completely removed, creating a space inside the mold shell. This space can be filled with conformal carbon felt, which helps to increase the temperature gradient and reduce grain defects. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the bottom-pouring gating system for single-crystal high-temperature alloy castings provided in this embodiment of the utility model; The components are: 1. Pour cup; 2. Casting wax model; 3. Central column tube; 4. Bottom sprue; 5. Base plate; 6. Connecting wax model; 601. Filter screen installation cylindrical section; 602. Sprue connecting cylindrical section; 603. Plug installation conical section; 7. Crystal selector wax model; 8. Riser wax model; 9. First boss; 10. Second boss. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0017] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0018] See Figure 1 A bottom-pouring gating system for single-crystal high-temperature alloy castings includes a pouring cup 1, a casting wax model 2, a central column tube 3, a bottom runner 4, and a base plate 5. The central column tube 3 is vertically installed in the middle of the base plate 5. The upper end of the central column tube 3 is connected to the pouring cup 1 via a connecting wax model 6. The connecting wax model 6 includes an upper filter screen mounting cylindrical section 601, a middle runner connecting cylindrical section 602, and a lower plug mounting conical section 603. The lower end of the casting wax model 2 is connected to the base plate 5 via a crystal selector wax model 7, and the upper end is connected to the upper end of the pouring cup 1 via a riser wax model 8. The upper end of the bottom runner 4 is connected to the runner connecting cylindrical section 602, and the lower end is connected to the bottom of the casting wax model 2.

[0019] In this embodiment, the lower part of the pouring cup 1 is designed with a cylindrical section (filter installation cylindrical section 601). After the mold shell is dewaxed, it will form a cylindrical cavity for installing a filter screen to filter metal inclusions. The upper part of the central column tube 3 is designed with a cylindrical section (sprue connecting cylindrical section 602) + a cone (plug installation cone section 603). The cylinder is used to arrange the starting position of the sprue along its circumference, and the cone is used to install a corundum plug before pouring to seal the central column tube 3. This can prevent the central column tube 3 from being filled with mold metal, reduce alloy waste, and reduce pouring costs.

[0020] See Figure 1 Specifically, the diameter of the cylindrical section 602 connecting the gating system is smaller than the diameter of the cylindrical section 601 for installing the filter screen, thus forming a step after dewaxing, which facilitates the installation of the filter screen.

[0021] When casting the mold shell prepared by the above-mentioned bottom-pouring casting system, the molten metal rises slowly due to the bottom-pouring filling method, avoiding core breakage caused by impact on the ceramic core. Inclusions float to the riser with the molten metal and can be removed, reducing fluorescence defects. The steady rise of the molten metal is conducive to grain growth.

[0022] See Figure 1 Understandably, in the actual design, multiple casting wax models 2 are evenly arranged around the central column tube. A partition plate (not shown in the figure) is also fixedly fitted onto the central column tube 3 near the connection point to the wax model 6. The partition plate can be made of plastic and fixed to the central column tube 3 by adhesive wax, or other materials can be used. A first boss 9 is provided on the chassis 5 between the central column tube 3 and the casting wax model 2.

[0023] During mold assembly, a plastic sheet is placed at the lower part of the conical structure of the central column tube 3. No shell is formed on the plastic sheet. After the mold assembly is shelled, the central column tube 3 sections above and below the plastic sheet can be separated. A ring of first bosses 9 is set inside the crystallization base 5. No shell is formed on the upper surface of these bosses. After the entire mold assembly is shelled and dewaxed, the inner and outer parts of the bosses can be separated. This allows the portion between the bosses and the plastic sheet to be completely removed, creating a space inside the mold shell. This space can be used to fill conformal carbon felt, which helps to increase the temperature gradient and reduce grain defects.

[0024] See Figure 1 In some embodiments, a second protrusion 10 can be added around the outer perimeter of the chassis 5. By setting a second protrusion 10, a ceramic retaining ring will be formed around the outer perimeter of the mold chassis 5. This design allows the ceramic retaining ring to effectively block the outflow of molten metal when there is steel leakage in the mold, thereby effectively protecting the equipment.

[0025] Unless otherwise stated, if any of the technical solutions disclosed in this utility model discloses a numerical range, then the disclosed numerical range is a preferred numerical range. Anyone skilled in the art should understand that the preferred numerical range is merely one among many feasible numerical values ​​that has a more obvious or representative technical effect. Because there are many numerical values, it is impossible to list them all. Therefore, this utility model discloses only some numerical values ​​to illustrate the technical solutions of the invention. Furthermore, the numerical values ​​listed above should not constitute a limitation on the scope of protection of this invention.

[0026] Meanwhile, if the present invention discloses or relates to mutually fixedly connected parts or structural components, then unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws), or a non-detachable fixed connection (e.g., riveting, welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured by casting) (except where it is obviously impossible to use an integral forming process).

[0027] Furthermore, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in this utility model include states or shapes that are similar to, analogous to, or close to those states or shapes. Any component provided by this utility model can be assembled from multiple individual components or can be a single component manufactured using a one-piece molding process.

[0028] The above embodiments are merely illustrative examples to clearly illustrate the present invention, and are not intended to limit the implementation. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A bottom-pouring gating system for single-crystal high-temperature alloy castings, comprising a pouring cup (1), a casting wax model (2), a central column tube (3), a bottom runner (4), and a base plate (5), characterized in that: The central column tube (3) is vertically installed in the middle of the chassis (5). The upper end of the central column tube (3) is connected to the pouring cup (1) through the connecting wax mold (6). The connecting wax mold (6) includes an upper filter screen mounting cylindrical section (601), a middle gating connecting cylindrical section (602), and a lower plug mounting conical section (603). The lower end of the casting wax mold (2) is connected to the chassis (5) through the crystal selector wax mold (7), and the upper end is connected to the upper end of the pouring cup (1) through the riser wax mold (8). The upper end of the bottom gating (4) is connected to the gating connecting cylindrical section (602), and the lower end is connected to the bottom of the casting wax mold (2).

2. The bottom-pouring gating system for single-crystal high-temperature alloy castings according to claim 1, characterized in that: A partition plate is fixedly fitted on the central column tube (3) near the connecting wax mold (6), and a first boss (9) is provided on the chassis (5) between the central column tube (3) and the casting wax mold (2).

3. The bottom-pouring gating system for single-crystal high-temperature alloy castings according to claim 2, characterized in that: The partition panel is made of plastic.

4. The bottom-pouring gating system for single-crystal high-temperature alloy castings according to any one of claims 1-3, characterized in that: The diameter of the cylindrical section (602) connecting the gating channel is smaller than the diameter of the cylindrical section (601) for installing the filter screen.

5. The bottom-pouring gating system for single-crystal high-temperature alloy castings according to any one of claims 1-3, characterized in that: Multiple wax molds (2) of the casting are evenly arranged around the central column tube (3).

6. The bottom-pouring gating system for single-crystal high-temperature alloy castings according to any one of claims 1-3, characterized in that: The chassis (5) has a second protrusion (10) around its outer perimeter.

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