An elongated thin-walled blade module manufacturing system and manufacturing process

Abstract

This invention belongs to the field of precision casting technology for turbine blades, and specifically relates to a slender, thin-walled blade module preparation system and process. The pouring cup is connected to one end of the central pouring pipe gating, the other end of the central pouring pipe gating is connected to the crown flower plate gating, and the side wall of the central pouring pipe gating is connected to the tenon disc gating. The tenon disc gating and the crown flower plate gating are respectively connected to both ends of the blade wax model. The tenon disc gating includes a first inner ring disc and multiple first connecting rods. The inner ring of the first inner ring disc is connected to the central pouring pipe gating, the outer ring of the first inner ring disc is connected to one end of the first connecting rod, and the other end of the first connecting rod is connected to the first outer ring disc. A tenon body is connected to the end face of the first outer ring disc facing the blade wax model. This allows the molten metal to first fill the entire disc of the tenon disc gating before flowing to the blade position, with more molten metal flowing through the central pouring pipe gating into the crown flower plate gating, making bottom pouring dominant in the preparation system.

Description

Technical Field

[0001] This invention belongs to the field of precision casting technology for turbine blades, and specifically relates to a system and process for preparing slender, thin-walled blade modules. Background Technology

[0002] Aero-engine power turbine blades are generally slender and thin-walled structures with long blade feeding channels that are also extremely prone to deformation, making it difficult to control metallurgical defects and dimensions.

[0003] The initial wax model preparation process for equiaxed, slender, thin-walled blades employed a modular process with 6 pieces per set and an ingate on the blade body. The area connecting the ingate to the blade body is the hottest region during solidification and also the last to solidify, making it prone to porosity defects, coarser grains, and blade deformation due to solidification shrinkage of the ingate. The average yield of various castings produced using this modular process was around 60%, with the main problems being near-surface fluorescence defects caused by the sprue in the blade body and dimensional deviations. Furthermore, the 6-piece / set modular process had low production efficiency, with alloy utilization only around 10%.

[0004] The current aero-engine blade manufacturing industry urgently needs a modular process that can improve the production efficiency and yield of equiaxed crystal slender thin-walled blades while reducing costs. Summary of the Invention

[0005] To address the aforementioned problems, this invention proposes a slender, thin-walled blade module fabrication system, comprising a pouring cup and a central inlet sprue; the pouring cup is connected to one end of the central inlet sprue, the other end of the central inlet sprue is connected to the leaf crown disc sprue, and the side wall of the central inlet sprue near the pouring cup is connected to the tenon disc sprue; multiple sets of blade wax models are evenly distributed in a circular pattern around the central inlet sprue; the tenon disc sprue and the leaf crown disc sprue are respectively connected to both ends of the blade wax models.

[0006] The tenon disc gating system includes an inner ring disc and multiple connecting rods. The inner ring of the inner ring disc is connected to the central injection pipe gating system, the outer ring of the inner ring disc is connected to one end of the connecting rod, and the other end of the connecting rod is connected to the outer ring disc. A tenon body is provided on the outer ring disc facing the blade wax model.

[0007] Furthermore, the leaf crown flower disc gating channel includes a second inner ring disc and multiple second connecting rods; the inner ring of the second inner ring disc is connected to the central injection pipe gating channel, and the outer ring of the second inner ring disc is connected to the second connecting rods; each of the second connecting rods is connected to a leaf crown body at the end away from the second inner ring disc.

[0008] Furthermore, the first connecting rod is a trapezoidal body, and the two corners of the first connecting rod facing the tenon body are respectively connected to the two tenon bodies.

[0009] Furthermore, the wider end of the first connecting rod is connected to the first outer ring disc.

[0010] Furthermore, the leaf crown body is provided with positioning marks; the tenon disc gating system is provided with raised marks at the corresponding positions of the leaf crown body marks.

[0011] Furthermore, the inner rings of the first inner ring disk and the second inner ring disk are square; one corner of the square is arc-shaped.

[0012] Furthermore, the central injection pipe gating system includes a No. 1 connector and a No. 2 connector; one end of the No. 1 connector is connected to the pouring cup, and the other end of the No. 1 connector is connected to a No. 3 connector; the No. 2 connector is connected to the leaf crown flower disc gating system; a No. 1 pipe body, a No. 2 pipe body, and a No. 3 pipe body are arranged sequentially between the No. 3 connector and the No. 2 connector; the No. 1 pipe body is a frustum, and the end of the No. 1 pipe body with the larger inner diameter is connected to the No. 1 connector.

[0013] Furthermore, a boss is provided between the first pipe body and the second pipe body, and between the second pipe body and the third pipe body.

[0014] This invention proposes a process for fabricating slender, thin-walled blade modules, applicable to any of the slender, thin-walled blade module fabrication systems described above, specifically including the following steps:

[0015] Modeling software was used to design a wax model assembly scheme for the modules;

[0016] The leaf crown gating system connects the leaf crown flower disc gating system with the leaf wax model.

[0017] The tenon gating system uses a tenon disc gating system connected to the blade wax model;

[0018] The central injection pipe gating system is connected to the pouring cup via connector No. 1, to the leaf crown flower plate gating system via connector No. 2, and to the tenon disc gating system via connector No. 3.

[0019] Numerical simulation software was used to simulate the defects and stress distribution of the module assembly scheme;

[0020] Prepare a wax mold gating system based on the wax mold assembly scheme model;

[0021] The wax mold runner is pressed using a wax mold and then combined with the blade wax mold to form a wax mold assembly.

[0022] The subsequent steps involve mold preparation and melting and casting to complete the preparation of the blade casting.

[0023] Furthermore, the preparation of the wax model gating mold based on the wax model combination scheme includes a central injection pipe gating mold, a tenon disc gating mold, and a leaf crown flower disc gating mold.

[0024] Beneficial effects

[0025] The advantages of this invention over the prior art are as follows:

[0026] 1. By adopting the disc structure of the tenon disc gating system, the molten metal first fills the entire disc of the tenon disc gating system before flowing to the blade position. More of the molten metal will flow through the central injection pipe gating system into the crown disc gating system, making bottom injection dominant in the preparation system.

[0027] 2. This application uses the No. 1 pipe as a transition gradient in the middle injection pipe gating channel, which increases the flow rate of molten metal flowing through the middle injection pipe gating channel during the casting process, increases the amount of metal injected at the bottom, and further makes the bottom injection dominate, optimizes the temperature gradient during the solidification process of the blade, and improves the metallurgical quality of the blade.

[0028] 3. This application adds positioning marks to the leaf crown plate gating and raised marks to the tenon disc gating, thereby ensuring that the same sequence number of the blades in different modules are in the same position in the preheating furnace and the casting furnace during the casting process, thus ensuring the consistency of the modules and facilitating the control of variables in the subsequent metallurgical defect analysis process.

[0029] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 A three-dimensional structural schematic diagram of the module in an embodiment of the present invention is shown.

[0032] Figure 2 A three-dimensional structural schematic diagram of the tenon disc gating system in an embodiment of the present invention is shown.

[0033] Figure 3 A top view of one side of the tenon disc gating system in an embodiment of the present invention is shown.

[0034] Figure 4 A top view of the other side of the tenon disc gating system in an embodiment of the present invention is shown.

[0035] Figure 5 A three-dimensional structural schematic diagram of the leaf crown flower disc irrigation channel in an embodiment of the present invention is shown.

[0036] Figure 6 A top view of one side of the leaf crown flower plate irrigation channel in an embodiment of the present invention is shown.

[0037] Figure 7 A top view of the other side of the leaf crown flower disc irrigation channel in an embodiment of the present invention is shown.

[0038] Figure 8 A top view of the inlet sprue in an embodiment of the present invention is shown.

[0039] In the diagram: 1. Sprue cup; 2. Inlet sprue; 21. Connector No. 1; 22. Pipe No. 1; 23. Pipe No. 2; 24. Pipe No. 3; 25. Connector No. 2; 26. Connector No. 3; 27. Boss; 3. Leaf crown sprue; 31. Inner ring plate No. 2; 32. Connecting rod No. 2; 33. Leaf crown body; 331. Positioning mark; 4. Tenon disc sprue; 41. Inner ring plate No. 1; 42. Connecting rod No. 1; 43. Tenon body; 44. Outer ring plate No. 1; 45. Raised mark; 5. Leaf wax model. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] This application provides a system for fabricating slender, thin-walled blade modules, with reference to... Figure 1 It includes a pouring cup 1 and a central pouring tube sprue 2; the pouring cup 1 is connected to one end of the central pouring tube sprue 2, the other end of the central pouring tube sprue 2 is connected to the leaf crown flower plate sprue 3, and the middle part of the central pouring tube sprue 2 near the pouring cup 1 is connected to the tenon disc sprue 4; the tenon disc sprue 4 and the leaf crown flower plate sprue 3 are respectively connected to both ends of the leaf wax model 5;

[0042] refer to Figure 2 , Figure 3 and Figure 4The tenon disc gating system 4 includes an inner ring disc 41 and multiple connecting rods 42. The inner ring of the inner ring disc 41 is connected to the central injection pipe gating system 2, and the outer ring of the inner ring disc 41 is connected to the connecting rods 42. The connecting rods 42 are connected to the outer ring disc 44, and the outer ring disc 44 is connected to the tenon body 43.

[0043] refer to Figure 5 , Figure 6 and Figure 7 The leaf crown flower disc gating channel 3 includes a second inner ring disc 31 and multiple second connecting rods 32; the inner ring of the second inner ring disc 31 is connected to the central injection pipe gating channel 2, and the outer ring of the second inner ring disc 31 is connected to the second connecting rods 32; each of the second connecting rods 32 is connected to the leaf crown body 33.

[0044] During implementation, the blade wax molds 5 are arranged in a circular pattern, with the air inlet side of the blade wax molds 5 facing outwards and the exhaust side facing inwards towards the central injection pipe gating 2; the module structure is illustrated using 12 pieces / set as an example; the height of the entire module is 439 mm, the maximum diameter at the top is 289 mm, and the maximum diameter of the sprue cup 1 is 178 mm; 12 cylindrical No. 2 connecting rods 32 are individually connected to the blade crown body 33; each connecting rod has a diameter of 15 mm and a length of 45 mm; the No. 2 connecting rods 32 are evenly distributed, and the included angle between any two adjacent No. 2 connecting rods 32 is 30°; the No. 2 inner ring plate 31 is connected to the central injection pipe gating 2 through a square slot, and the No. 1 inner ring plate 41 is also connected to the central injection pipe gating 2 through a square slot; the maximum diameter of the blade crown flower plate gating 3 is 289 mm;

[0045] During module assembly, the sprue cup 1 is positioned downwards for support, and then the central injection pipe sprue 2, tenon disc sprue 4, blade wax model 5, and leaf crown disc sprue 3 are installed. During the pouring process, the sprue cup 1 is positioned upwards. The molten metal flows into the central injection pipe sprue 2 through the sprue cup 1. The molten metal is divided in the central injection pipe sprue 2, with a portion flowing into the tenon disc sprue 4 and the other portion continuing to flow into the leaf crown disc sprue 3 through the central injection pipe sprue 2.

[0046] In the prior art, during the pouring process of the tenon gating system, the molten metal quickly flows through the tenon gating system to the position of the blade wax model 5, with top pouring being dominant. In this application, the molten metal flows into the first inner ring plate 41 through the middle pouring pipe gating system 2, and then flows into the first outer ring plate 44 through the first connecting rod 42. Only after the first outer ring plate 44 is filled with molten metal will it flow through the tenon body 43 to the position of the blade wax model 5. More molten metal will flow through the middle pouring pipe gating system 2 to the position of the crown flower plate gating system 3. After passing through the second inner ring plate 31 and the second connecting rod 32 in the crown flower plate gating system 3, it will then flow through the crown body 33 to the position of the blade wax model 5. Thus, the entire preparation system combines bottom pouring and top pouring, with bottom pouring being dominant.

[0047] In the prior art, the connecting rod has a large connection area. In this application, the second connecting rod 32 is a slender cylinder with a small connection area. Therefore, the shrinkage stress acting on the crown body 33 during solidification is small, which is beneficial for controlling the deformation of the crown body 33.

[0048] The leaf crown plate sprue 3, tenon disc sprue 4, and central injection pipe sprue 2 are placed using special tooling and the placement time is more than 24 hours. The leaf crown plate sprue 3, tenon disc sprue 4, and central injection pipe sprue 2 fully shrink and release stress and reduce deformation during the placement process, preventing stress from being transferred to the leaf wax model 5 during the assembly process and causing deformation of the leaf wax model 5.

[0049] This application adopts the disc structure of the tenon disc gating 4 for the tenon gating, so that the molten metal fills the entire disc of the tenon disc gating 4 before flowing to the blade position. More of the molten metal will flow through the central injection pipe gating 2 to the crown flower disc gating 3, making the bottom injection of the preparation system dominant. The wax mold module is expanded to 12 pieces / set, which improves production efficiency and alloy utilization and significantly reduces production costs.

[0050] This application eliminates the internal gate of the blade body, and the blade wax models 5 are distributed in a circle, which simplifies the difficulty of mold assembly and reduces the workload of mold assembly; eliminating the internal gate can avoid metallurgical quality and dimensional deviation problems, and greatly improve the qualification rate of castings;

[0051] In one embodiment of the present invention, the first connecting rod 42 is a trapezoidal body, and the two corners of the first connecting rod 42 facing the tenon body 43 are respectively connected to the two tenon bodies 43.

[0052] The wider end of the first connecting rod 42 is connected to the first outer ring disc 44.

[0053] The first connecting rod 42 of the trapezoidal body is used to achieve the ring-shaped interconnection, which is connected to the first inner ring disk 41 and the first outer ring disk 44; the module of 12 sets of blade wax molds 5 contains 6 sets of the first connecting rod 42; the width of the first outer ring disk 44 is 47 mm, and the maximum diameter is 274 mm; the width of the first connecting rod 42 is uniformly transitioned from 35 mm to 21 mm.

[0054] In one embodiment of the present invention, a positioning mark 331 is provided on the leaf crown body 33.

[0055] The tenon disc gating 4 has a raised mark 45 at the corresponding mark position of the leaf crown body 33.

[0056] The inner rings of the first inner ring disk 41 and the second inner ring disk 31 are square; one corner of the square is arc-shaped.

[0057] During implementation, positioning marks 331 of 1, 4, 7 and 10 were set on the 12 blade crown bodies 33 respectively; this ensures that blades with the same sequence number in different modules are in the same position during assembly. At the same time, a hemispherical raised mark 45 was added to the tenon disc gating sprue 4 at the position corresponding to the blade crown body 33 marked with 1, and an arc-shaped anti-error design was added to the first inner ring disc 41 and the second inner ring disc 31. This ensures that blades with the same sequence number in different modules are in the same position in the preheating furnace and the casting furnace during casting; thus ensuring the consistency of the modules and facilitating the control of variables in the subsequent metallurgical defect analysis process.

[0058] In one embodiment of the present invention, reference is made to Figure 8 The central injection pipe gating system 2 includes a first connector 21 and a second connector 25; one end of the first connector 21 is connected to the pouring cup 1, and the other end of the first connector 21 is connected to a third connector 26; the second connector 25 is connected to the leaf crown flower disc gating system 3; a first pipe body 22, a second pipe body 23, and a third pipe body 24 are arranged sequentially between the third connector 26 and the second connector 25; the first pipe body 22 is a frustum, and the end of the first pipe body 22 with a larger inner diameter is connected to the first connector 21.

[0059] In one embodiment of the present invention, a boss 27 is provided between the first tube 22 and the second tube 23, and between the second tube 23 and the third tube 24.

[0060] During implementation, the length of the central injection pipe is 388 mm, and the maximum diameter is 101 mm; connector 21 is connected to the pouring cup 1; connectors 25 and 36 are provided with channels, allowing the molten metal inside the central injection pipe gating 2 to flow into the crown-shaped plate gating 3 and the tenon-shaped plate gating 4 respectively through connectors 25 and 36; the central injection pipe gating 2 is divided into three sections: pipe body 22, pipe body 23, and pipe body 24; the diameter of pipe body 22 transitions evenly from 39 mm near the pouring cup 1 to 30 mm; the diameters of pipe bodies 23 and 24 are both 30 mm; the diameter of the boss 27 is 38 mm, and the boss 27 is designed... The design improves the strength of the central injection pipe gating 2 and reduces its deformation. Compared with existing technologies, the diameter of the central injection pipe gating 2 is increased by 15-25 mm, and a first pipe body 22 serves as a transition gradient near the pouring cup 1. This increases the flow rate of molten metal flowing through the central injection pipe gating 2 during the pouring process, resulting in a greater amount of metal poured at the bottom, further making bottom pouring dominant in the preparation system. This optimizes the temperature gradient during the blade solidification process, which is more conducive to the filling of loose areas in the thinner blade wall during the solidification of slender, thin-walled blades. The number of defective and scrapped blades is significantly reduced, and the metallurgical quality of the blades is greatly improved, with an average pass rate of over 70%.

[0061] This application provides a process for fabricating a slender, thin-walled blade module, applicable to any of the aforementioned slender, thin-walled blade module fabrication systems, specifically including the following steps:

[0062] Modeling software was used to design a wax model assembly scheme for the modules;

[0063] The leaf crown gating system is connected to the leaf crown flower plate gating system 3 and the leaf wax model 5;

[0064] The tenon sprue is connected to the blade wax mold 5 via a tenon disc sprue 4.

[0065] The central injection pipe sprue 2 is connected to the pouring cup 1 via connector 21, and to the leaf crown flower plate sprue 3 via connector 25. Connector 26 is connected to the tenon disc sprue 4.

[0066] Numerical simulation software was used to simulate the defects and stress distribution of the module combination scheme; and the model was further optimized to avoid defect accumulation areas and stress concentration areas on the blade wax model 5.

[0067] The wax mold sprue mold is prepared according to the wax mold combination scheme model; it consists of three sets of wax mold sprue molds: central injection pipe sprue mold, tenon disc sprue mold, and leaf crown disc sprue mold; the wax mold sprue mold ensures smooth and complete pressing of the wax mold sprue while also ensuring ease of operation;

[0068] The wax mold runner is pressed using a wax mold runner mold and then combined with the blade wax mold 5 to form a wax mold assembly.

[0069] The subsequent steps involve mold preparation and melting and casting to complete the preparation of the blade casting.

[0070] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An elongated thin-walled vane mold set production system, characterized by, It includes a pouring cup (1) and a central pouring tube gating system (2); the pouring cup (1) is connected to one end of the central pouring tube gating system (2), the other end of the central pouring tube gating system (2) is connected to the leaf crown flower plate gating system (3), the side wall of the central pouring tube gating system (2) near the pouring cup (1) is connected to the tenon disc gating system (4), and multiple sets of leaf wax models (5) are evenly distributed in a circle around the central pouring tube gating system (2); the tenon disc gating system (4) and the leaf crown flower plate gating system (3) are respectively connected to both ends of the leaf wax model (5); The tenon disc gating system (4) includes an inner ring disc (41) and multiple connecting rods (42); the inner ring of the inner ring disc (41) is connected to the central injection pipe gating system (2), the outer ring of the inner ring disc (41) is connected to one end of the connecting rod (42), and the other end of the connecting rod (42) is connected to the outer ring disc (44); a tenon body (43) is provided on the end face of the outer ring disc (44) facing the blade wax model (5). The leaf crown flower disc gating channel (3) includes a second inner ring disc (31) and multiple second connecting rods (32); the inner ring of the second inner ring disc (31) is connected to the central injection pipe gating channel (2), and the outer ring of the second inner ring disc (31) is connected to the second connecting rods (32); each second connecting rod (32) has a leaf crown body (33) connected to one end away from the second inner ring disc (31). The inlet sprue (2) includes a first connector (21) and a second connector (25); one end of the first connector (21) is connected to the pouring cup (1), and the other end of the first connector (21) is connected to the third connector (26); the second connector (25) is connected to the leaf crown flower plate sprue (3); the third connector (26) and the second connector (25) are arranged in sequence with a first tube body (22), a second tube body (23) and a third tube body (24); the first tube body (22) is a frustum, and the end of the first tube body (22) with a larger inner diameter is connected to the first connector (21) through the third connector (26); the third connector (26) is connected to the tenon disc sprue (4).

2. The slender thin-walled blade module fabrication system according to claim 1, characterized in that, The first connecting rod (42) is a trapezoidal body, and the two corners of the first connecting rod (42) facing the tenon body (43) are respectively connected to the two tenon bodies (43).

3. The slender thin-walled blade module fabrication system according to claim 2, characterized in that, The wider end of the first connecting rod (42) is connected to the first outer ring disc (44).

4. The slender thin-walled blade module fabrication system according to claim 3, characterized in that, The leaf crown body (33) is provided with a positioning mark (331); the tenon disc gating (4) is provided with a raised mark (45) at the corresponding mark position of the leaf crown body (33).

5. The slender thin-walled blade module fabrication system according to claim 4, characterized in that, The inner rings of the first inner ring disk (41) and the second inner ring disk (31) are square; the corners of the square are arc-shaped.

6. The slender thin-walled blade module fabrication system according to claim 5, characterized in that, A boss (27) is provided between the first pipe body (22) and the second pipe body (23), and between the second pipe body (23) and the third pipe body (24).

7. A process for fabricating a slender, thin-walled blade module, applied to the slender, thin-walled blade module fabrication system described in any one of claims 1-6, characterized in that, Specifically, the steps include the following: Modeling software was used to design a wax model assembly scheme for the modules; The leaf crown gating channel is connected to the leaf crown flower plate gating channel (3) and the leaf wax model (5); The tenon gating system is connected to the blade wax model (5) via a tenon disc gating system (4); The central injection pipe gating (2) is connected to the pouring cup (1) by connector No. 1 (21), to the leaf crown flower plate gating (3) by connector No. 2 (25), and to the tenon disc gating (4) by connector No. 3 (26). Numerical simulation software was used to simulate the defects and stress distribution of the module assembly scheme; Prepare a wax mold gating system based on the wax mold assembly scheme model; The wax mold is pressed using a wax mold sprue mold and combined with the blade wax mold (5) to form a wax mold assembly; The subsequent steps involve mold preparation and melting and casting to complete the preparation of the blade casting.

8. The manufacturing process of a slender, thin-walled blade module according to claim 7, characterized in that, The wax model sprue mold prepared according to the wax model combination scheme includes a central injection pipe sprue mold, a tenon disc sprue mold, and a leaf crown disc sprue mold.

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