Anti-cracking wax mold base for single crystal blade and mold thereof

Abstract

The utility model belongs to investment precision casting technical field, specifically discloses a kind of anti-cracking wax mould base for single crystal blade and its mould, wax film base includes base body, the top surface of base body is provided with reinforcing rib and positioning boss, reinforcing rib is provided with multiple from inside to outside, positioning boss is set to multiple according to setting mode, multiple positioning boss is surrounded by at least one reinforcing rib;Mould includes upper die and lower die, and lower die is provided with lower cavity with opening upward, and upper die is provided with upper cavity with opening downward, and upper die and lower die are connected by detachable mode to constitute mould, and the upper cavity and lower cavity are mutually aligned and communicated to form the mould cavity for forming base body in closed die state;Upper cavity is provided with reinforcing rib cavity and boss forming cavity;The utility model is surrounded by positioning boss by the design of reinforcing rib and enhances the local structural strength of base, effectively suppresses crack propagation and improves positioning accuracy.

Description

Technical Field

[0001] This utility model belongs to the field of investment casting technology, and in particular relates to a crack-resistant wax mold base plate and mold for single crystal blades. Background Technology

[0002] The manufacturing of single-crystal turbine blades for aero-engines is highly dependent on investment casting. This process first assembles the blade wax model and the gating system wax model into a complete wax model assembly. Then, ceramic shells are prepared through processes such as slurry application and sand application. After dewaxing and firing, molten metal is injected into the shell for directional solidification, ultimately forming a single-crystal blade.

[0003] In the wax mold assembly structure, the chassis serves as the core connecting component, connecting the central injection tube and the spiral crystal selector. A typical chassis adopts a circular design, with blades distributed in a ring array on the chassis surface, and the central injection tube fixed at the center of the chassis. The assembly efficiency of the blades and the wax mold chassis directly restricts the overall production cycle time. Existing chassis structures are prone to positioning deviations during rapid assembly, making it difficult to improve production efficiency. More critically, after the ceramic shell is prepared, the chassis area needs to be polished to expose the crystal selector cavity. Due to insufficient structural strength, the chassis is highly susceptible to microcracks under the high temperature and pressure environment of dewaxing or metal casting. These cracks can not only cause molten metal leakage leading to casting failure, but also extend into the crystal selector area, inducing serious defects such as blade flash, impurities, or abnormal crystal orientation.

[0004] This demonstrates that existing chassis designs lack effective crack-resistant mechanisms, making it difficult to balance rapid assembly with structural stability. This results in high scrap rates and inconsistent quality during production. Therefore, there is an urgent need for a chassis structure that can fundamentally suppress crack formation and optimize the assembly process to resolve the conflict between production efficiency and quality stability.

[0005] To address the aforementioned issues, existing technologies urgently need improvement. Utility Model Content

[0006] The purpose of this invention is to provide a crack-resistant wax mold base and mold for single crystal blades, which has the advantages of effectively suppressing crack generation, improving structural stability, optimizing assembly process, reducing scrap rate, and ensuring production efficiency and quality consistency, so as to solve the problems of poor crack resistance and low production efficiency in the prior art.

[0007] To achieve the above objectives, the technical solution of this utility model is as follows: a crack-resistant wax mold base for single crystal blades, comprising a base body, the top surface of which is provided with reinforcing ribs and positioning bosses, the reinforcing ribs being arranged in multiple directions from the inside out, and the positioning bosses being arranged in multiple ways, with at least one reinforcing rib surrounding each positioning boss.

[0008] Furthermore, the chassis body has a circular structure, and the reinforcing ribs are radially closed annular structures with multiple reinforcing ribs arranged concentrically, with the center of the ring being the top surface of the chassis body.

[0009] Furthermore, the multiple positioning bosses include a central injection pipe positioning boss and blade positioning bosses. The central injection pipe positioning boss is located at the center of the top surface of the chassis body. There are multiple blade positioning bosses, which are arranged in a ring array around the center of the top surface of the chassis body. Each blade positioning boss is surrounded by at least one reinforcing rib.

[0010] Furthermore, this utility model also discloses a mold for molding the anti-crack wax mold chassis for single crystal blades as described above. The mold includes an upper mold and a lower mold. The lower mold is provided with a lower cavity with an upward opening, and the upper mold is provided with an upper cavity with a downward opening. The upper mold and the lower mold are connected and closed in a detachable manner to form a mold. In the closed state, the upper cavity and the lower cavity are aligned with each other and connected to form a mold cavity for molding the chassis body. The top surface of the upper cavity is provided with reinforcing rib cavities corresponding to the positions of each reinforcing rib for forming each reinforcing rib. The top surface of the upper cavity is also provided with boss forming cavities corresponding to the positions of each positioning boss for forming each positioning boss.

[0011] Furthermore, it also includes a wax injection port for the wax liquid to enter the mold cavity. The wax injection port consists of a tapered section and a straight section. The tapered section includes a tapered upper section set in the upper mold and a tapered lower section set in the lower mold. The tapered upper section and the tapered lower section form a trumpet-shaped structure with a larger front and a smaller back when the mold is closed. The straight section includes a straight upper section set in the upper mold and a straight lower section set in the lower mold at the corresponding position of the straight upper section. The straight upper section connects the tapered upper section to the upper cavity, and the straight lower section connects to the tapered lower section. The end of the straight lower section has an arc-shaped structure.

[0012] Furthermore, it also includes opening and closing pry bars, which are set on the upper mold and / or lower mold and located at the joint surface of the upper mold and lower mold. Multiple opening and closing pry bars are provided, and the multiple opening and closing pry bars are evenly distributed along the circumference of the mold.

[0013] Furthermore, the upper mold has upper guide post holes for installing guide posts, and the lower mold has lower guide post holes, with the lower guide post holes corresponding one-to-one with the upper guide post holes.

[0014] The beneficial effects of this technical solution are as follows:

[0015] This utility model discloses a crack-resistant wax mold base and mold for single crystal blades. By setting multiple reinforcing ribs on the base body, it is ensured that even if cracks occur in the final ceramic shell, the stress can be released when the cracks extend to the position of the reinforcing ribs, thereby effectively limiting the expansion of cracks. The setting of multiple positioning bosses enables rapid positioning of the wax film in the injection tube and the blade wax film, and facilitates bonding.

[0016] Compared with existing technologies, the wax mold chassis and its mold of this utility model enhance the local structural strength of the chassis by reinforcing ribs surrounding the positioning boss, effectively suppressing crack propagation and improving positioning accuracy. It has the advantages of effectively suppressing crack generation, improving structural stability, optimizing assembly process, reducing scrap rate, and ensuring production efficiency and quality consistency. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a crack-resistant wax mold base for single-crystal blades according to the present invention;

[0018] Figure 2 This is a cross-sectional structural diagram of the mold of this utility model;

[0019] Figure 3 This is a schematic diagram of the upper mold of this utility model;

[0020] Figure 4 This is a schematic diagram of the lower mold of this utility model. Detailed Implementation

[0021] The following detailed description illustrates the specific implementation method:

[0022] The reference numerals in the accompanying drawings include: chassis body 1, reinforcing rib 2, central injection tube positioning boss 3, blade positioning boss 4, upper mold 5, lower mold 6, upper cavity 7, lower cavity 8, reinforcing rib cavity 9, boss forming cavity 10, tapered upper segment 11, tapered lower segment 12, straight upper segment 13, straight lower segment 14, upper guide post hole 15, lower guide post hole 16, opening and closing pry hole 17.

[0023] 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.

[0024] The basic implementation examples are as follows: Figure 1The image shows a crack-resistant wax mold chassis and its mold for single-crystal blades. The chassis body 1 has reinforcing ribs 2 and positioning bosses on its top surface. Multiple reinforcing ribs 2 are arranged from the inside out, and multiple positioning bosses are arranged in a specific configuration, with at least one reinforcing rib 2 surrounding each positioning boss. Specifically, the chassis body 1, as the basic load-bearing component of the overall structure, has reinforcing ribs 2 and positioning bosses on its top surface forming a collaborative system. Multiple reinforcing ribs 2 are arranged from the inside out, forming a radial stress dispersion network. This network serves two main purposes: firstly, by increasing local stiffness, it effectively alleviates the concentrated stress generated by external loads on the chassis surface, thereby inhibiting crack initiation; secondly, if a crack has already formed, the stress can be released when the crack extends to the location of the reinforcing rib 2, effectively limiting crack propagation. Furthermore, the design of multiple positioning bosses being surrounded by at least one reinforcing rib 2 creates a continuous protective boundary around the positioning bosses, blocking the path of crack propagation from the positioning bosses or towards critical areas, particularly strengthening the structural integrity of stress concentration points. The positioning boss is used to achieve rapid and accurate positioning of the blades and the injection tube, reducing assembly deviations and improving the assembly efficiency of the wax mold assembly. Therefore, the reinforcing rib 2 not only improves the overall strength of the chassis but also specifically reinforces vulnerable areas such as the positioning boss, maintaining the stability of the chassis structure during dewaxing and casting, and preventing steel leakage and casting failure caused by cracks. Thus, the chassis body 1 in this embodiment achieves enhanced crack resistance and improved assembly reliability through structural optimization, while ensuring stable connections between all components of the wax mold assembly, meeting the requirements of efficient production and high-quality stability.

[0025] In this embodiment, the chassis body 1 is a circular structure, and the reinforcing ribs 2 are radially closed annular structures. Multiple reinforcing ribs 2 are concentrically arranged, with the center of the ring being the top surface of the chassis body 1. Specifically, the reinforcing ribs 2 are auxiliary structures used to enhance the strength of the chassis. Their radially closed annular design creates a continuous and uninterrupted support path. The concentric arrangement of multiple reinforcing ribs 2 ensures that they are evenly distributed radially, guaranteeing consistent strength across different areas of the chassis. The layout, where the center of the ring coincides with the center of the top surface of the chassis body 1, allows the positioning boss 3 of the injection tube to be located at the core position where stress is most evenly distributed, making it particularly suitable for the connection requirements of the blade annular array in single-crystal blade wax modules. By combining the circular structure design of the chassis body 1 with the annular layout of the reinforcing ribs 2, a uniform distribution of overall chassis strength is achieved. The circular structure of the chassis body 1 not only facilitates the even distribution of the reinforcing ribs 2 concentrically but also avoids stress concentration problems caused by irregular shapes. The radially closed annular structure of the reinforcing ribs 2 provides a continuous support path, effectively surrounding the positioning boss and preventing cracks from propagating from weak points. The concentric arrangement of multiple reinforcing ribs 2 further enhances the chassis's crack resistance during dewaxing and casting processes, while ensuring consistent strength across all areas of the chassis. Furthermore, the alignment of the ring center with the center of the top surface of the chassis body 1 places the positioning boss 3 of the central injection tube in the most evenly stressed position, improving the overall structural stability and reliability. This design is particularly suitable for the connection requirements of the blade ring array in single-crystal blade wax modules, fundamentally solving the stress concentration and crack risk caused by irregular shapes.

[0026] In this embodiment, the multiple positioning bosses include a central injection pipe positioning boss 3 and blade positioning bosses 4. The central injection pipe positioning boss 3 is located at the center of the top surface of the chassis body 1. Multiple blade positioning bosses 4 are arranged in a circular array around the center of the top surface of the chassis body 1, and each blade positioning boss 4 is surrounded by at least one reinforcing rib 2. Specifically, the central injection pipe positioning boss 3 is a structure used to fix the central injection pipe and ensure its centered connection in the wax mold assembly; it is one and located at the center of the top surface of the chassis body 1. The blade positioning bosses 4 are structures used to fix the blade wax molds and ensure their distribution in a circular array; multiple blade positioning bosses are provided. As a preferred embodiment, two reinforcing ribs 2 are provided in this embodiment. One rib is arranged radially around the outside of the blade positioning bosses 4 to surround all the blade positioning bosses 4, and the other rib is arranged radially between the blade positioning bosses 4 and the central injection pipe positioning boss, surrounding the central injection pipe positioning boss while separating the blade positioning bosses 4 from the central injection pipe positioning boss. This design utilizes the annular support characteristics of the reinforcing rib 2 to disperse the thermal stress and mechanical load during dewaxing or casting, effectively preventing the initiation and propagation of cracks. Through the aforementioned technical solution, not only is precise positioning of the injection tube and blade wax mold achieved, but the crack resistance of the wax mold chassis is also significantly improved, providing a reliable guarantee for improving production efficiency and product quality.

[0027] like Figure 2-4As shown, this embodiment also discloses a mold for molding the anti-crack wax mold chassis for single crystal blades as described above. The mold includes an upper mold 5 and a lower mold 6. The lower mold 6 is provided with a lower cavity 8 with an upward opening, and the upper mold 5 is provided with an upper cavity 7 with a downward opening. The upper mold 5 and the lower mold 6 are connected and closed in a detachable manner to form a mold. In the closed state, the upper cavity 7 and the lower cavity 8 are aligned with each other and connected to form a mold cavity for molding the chassis body 1. The top surface of the upper cavity 7 is provided with reinforcing rib cavities 9 corresponding to the positions of each reinforcing rib 2 for forming each reinforcing rib 2. The top surface of the upper cavity 7 is also provided with boss forming cavities 10 corresponding to the positions of each positioning boss for forming each positioning boss. Specifically, the top surface of the upper cavity 7 is provided with reinforcing rib cavities 9 corresponding to the positions of each reinforcing rib 2. This means that the reinforcing rib cavities 9 are provided on the top surface of the upper cavity 7 according to the number and position of the reinforcing ribs 2 set in the chassis body 1 to ensure the forming of the reinforcing ribs 2. Similarly, the top surface of the upper cavity 7 is provided with boss forming cavities 10 according to the size, structure, position and number of each positioning boss (including the central column positioning boss and the blade positioning boss 4) to ensure the final forming of each positioning boss. The wax film chassis formed by this mold, under the synergistic effect of the reinforcing ribs 2 and each positioning boss, achieves enhanced crack resistance and improved assembly reliability, while ensuring the stable connection of each component of the wax mold assembly, meeting the requirements of efficient production and high-quality stability. As a preferred embodiment, the cross-section of the reinforcing rib cavity 9 is semi-circular, and its radius can be selected as 3-5mm according to actual needs.

[0028] In this embodiment, a wax injection port is also included for the wax to enter the mold cavity. The wax injection port consists of a tapered section and a straight section. The tapered section includes a tapered upper section 11 located in the upper mold 5 and a tapered lower section 12 located in the lower mold 6. The tapered upper section 11 and the tapered lower section 12 form a trumpet-shaped structure with a larger front and a smaller back when the mold is closed. The straight section includes a straight upper section 13 located in the upper mold 5 and a straight lower section 14 located in the lower mold 6 at the corresponding position of the straight upper section 13. The straight upper section 13 connects the tapered upper section 11 to the upper cavity 7, and the straight lower section 14 connects to the tapered lower section 12. The end of the straight lower section 14 has an arc-shaped structure. Specifically, the wax injection port is a channel structure that guides the wax into the mold cavity. Its purpose is to optimize the wax flow path and improve the filling quality. In this embodiment, the straight lower section 14 is not directly connected to the mold cavity. The tapered section is a flow channel structure with a gradually decreasing cross-section. It can be precision-machined to form a smooth inner wall, thereby reducing the resistance to wax flow. The straight section provides a stable, straight flow channel, which can be achieved through high-precision mold machining. Its purpose is to maintain a stable wax flow rate and prevent air bubble retention. The organic combination of the tapered and straight sections achieves a smooth transition of the wax. The tapered section adopts a trumpet-shaped structure that is larger at the front and smaller at the back, gradually reducing the wax flow rate and avoiding turbulence caused by high-speed flow. The upper tapered section 11 and the lower tapered section 12 fit precisely during mold closing to ensure the continuity of the flow path. The straight section forms a complete flow channel through the connection between the upper straight section 13 and the upper cavity 7, and the connection between the lower straight section 14 and the lower tapered section 12. In particular, the arc-shaped structure design at the end of the lower straight section 14 effectively eliminates sharp edges, reduces flow resistance, and prevents air bubbles from accumulating at the end. This design, combined with the detachable connection between the upper mold 5 and the lower mold 6, ensures the stability and reliability of the wax injection process after the mold is closed, thereby significantly improving the molding quality of the wax model.

[0029] This embodiment also includes opening and closing pry bars 17, which are disposed on the upper mold 5 and / or the lower mold 6 at the mating surface of the upper mold 5 and the lower mold 6. Multiple opening and closing pry bars 17 are provided, evenly distributed along the circumference of the mold. Specifically, the opening and closing pry bars 17 are structures used to assist in the opening and closing operation of the mold. They are groove structures formed on the surface of the mold, providing a force application point to reduce the initial resistance during mold separation. The opening and closing pry bars 17 are disposed at the mating surface of the upper mold 5 and / or the lower mold 6, directly corresponding to the stress concentration area of ​​the mold closing interface, allowing the prying tool to accurately act on the separation initiation point, thereby effectively reducing the initial separation resistance. The arrangement of multiple opening and closing pry bars 17 can be flexibly adjusted according to the specific size of the mold and the force requirements. For example, they can be disposed only on the upper mold 5 or the lower mold 6, or simultaneously on both the upper mold 5 and the lower mold 6. They can be symmetrically distributed or distributed in multiple points to ensure uniform transmission of the opening and closing force. The design of multiple opening and closing pry bars 17 evenly distributed along the circumference of the mold is based on the principle of symmetrical force distribution, aiming to eliminate the risk of mold twisting caused by torque imbalance. In this embodiment, the mold has a rectangular structure, and four opening and closing pry bars 17 are located at the four corners of the top surface of the lower mold 6. By setting the opening and closing pry bars 17, the mold is ensured to have higher operational convenience and structural stability during opening and closing, thereby improving production continuity and mold lifespan.

[0030] In this embodiment, the upper mold 5 has upper guide post holes 15 for mounting guide posts, and the lower mold 6 has lower guide post holes 16, with each lower guide post hole 16 corresponding to one of the upper guide post holes 15. Specifically, the purpose of introducing the guide post hole structure is to provide a precise guiding reference for the mold closing process. The upper guide post holes 15 and lower guide post holes 16 can be achieved by mechanical drilling, laser drilling, or electrical discharge machining. The one-to-one correspondence ensures that the upper guide post holes 15 and lower guide post holes 16 maintain a strict matching relationship in terms of position and number. By setting guide post hole structures in the upper mold 5 and lower mold 6 respectively, a complete guiding system is formed. Based on this, combined with the molding requirements of the aforementioned chassis body 1, reinforcing ribs 2, and positioning bosses, this guiding system significantly improves the molding accuracy of the wax mold chassis, reduces the risk of structural defects caused by mold cavity misalignment, and thus enhances the overall strength and reliability of the shell chassis.

[0031] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0032] The above descriptions are merely embodiments of this utility model. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are knowledgeable of all existing technologies in that field, and possess the ability to apply conventional experimental methods prior to that date. Therefore, those skilled in the art can, based on the guidance provided in this application, improve and implement this solution in conjunction with their own capabilities. Typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A crack-resistant wax mold base for single-crystal blades, characterized in that: The chassis body includes a chassis body, and the top surface of the chassis body is provided with reinforcing ribs and positioning bosses. There are multiple reinforcing ribs arranged from the inside to the outside, and multiple positioning bosses are arranged in a certain way, with at least one of the multiple positioning bosses being surrounded by one of the reinforcing ribs.

2. The anti-crack wax mold base for single-crystal blades according to claim 1, characterized in that: The chassis body is a circular structure, and the reinforcing ribs are radially closed annular structures. Multiple reinforcing ribs are arranged concentrically, with the center of the ring being the center of the top surface of the chassis body.

3. The anti-crack wax mold base for single-crystal blades according to claim 1, characterized in that: The plurality of positioning bosses include a central injection pipe positioning boss and a blade positioning boss, wherein the central injection pipe positioning boss is located at the center of the top surface of the chassis body. The blade positioning bosses are provided in multiple ways, and the multiple blade positioning bosses are arranged in a ring array around the center of the top surface of the chassis body. The multiple blade positioning bosses are surrounded by at least one reinforcing rib.

4. A mold for molding a crack-resistant wax mold base for single-crystal blades as described in any one of claims 1-3, characterized in that: The mold includes an upper mold and a lower mold. The lower mold has an upward-opening lower cavity, and the upper mold has a downward-opening upper cavity. The upper mold and the lower mold are detachably connected to form a mold. In the molded state, the upper cavity and the lower cavity are aligned and connected to each other to form a mold cavity for molding the chassis body. The top surface of the upper cavity is provided with reinforcing rib cavities corresponding to the positions of each reinforcing rib, and the top surface of the upper cavity is also provided with boss forming cavities corresponding to the positions of each positioning boss.

5. The mold according to claim 4, characterized in that: It also includes a wax injection port for the wax liquid to enter the mold cavity. The wax injection port is composed of a tapered section and a straight section. The tapered section includes a tapered upper section disposed on the upper mold and a tapered lower section disposed on the lower mold. The tapered upper section and the tapered lower section form a trumpet-shaped structure with a larger front and a smaller back when the mold is closed. The straight section includes a straight upper section disposed on the upper mold and a straight lower section disposed on the lower mold at the corresponding position of the straight upper section. The straight upper section connects the tapered upper section to the upper cavity, and the straight lower section connects to the tapered lower section. The end of the straight lower section has an arc surface structure.

6. The mold according to claim 4, characterized in that: It also includes opening and closing pry bars, which are provided on the upper mold and / or the lower mold and located at the joint surface of the upper mold and the lower mold. Multiple opening and closing pry bars are provided, and the multiple opening and closing pry bars are evenly distributed along the circumference of the mold.

7. The mold according to claim 4, characterized in that: The upper mold has upper guide post holes for installing guide posts, and the lower mold has lower guide post holes, with the lower guide post holes corresponding one-to-one with the upper guide post holes.

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