Casting complex inner cavity special-shaped hole channel blocking method

Abstract

The invention discloses a plugging method for a special-shaped hole channel of a complex inner cavity of a casting, and belongs to the technical field of casting manufacturing. Comprising the following steps: grinding one end of a spherical plugging material bead, and spot-welding an assembly traction flexible wire on the ground surface of the material bead; wrapping the plugging material beads by a circle by using adhesive tape brazing filler metal; the ball-plugging-shaped material balls are conveyed to a to-be-brazed position, and the assembling traction flexible wire penetrates through a casting inner cavity corresponding to the whole to-be-plugged hole channel; the spherical plugging material bead is dragged by assembling a traction flexible wire, so that the adhesive tape brazing filler metal is attached to the surface of the inner cavity of the casting and the spherical plugging material bead; and the assembly traction flexible wire is snapped, the casting is moved to a vacuum brazing furnace to be brazed, and the casting with the blocked inner cavity special-shaped hole channel is obtained. According to the method, the sealing quality and efficiency of the special-shaped hole channel of the complex inner cavity of the casting are improved, a more reliable, economical and environment-friendly solution is provided for the field of casting manufacturing through the innovative design and method, development of the casting manufacturing technology can be further promoted, and the requirement for high-performance castings is met.

Description

Technical Field

[0001] The invention relates to the technical field of casting manufacturing, and in particular to a method for plugging special-shaped channels in complex inner cavities of castings. Background Art

[0002] In the field of modern industrial manufacturing, castings are widely used in various machinery, automobiles, aviation and heavy industry products due to their good material properties and cost-effectiveness. The design of castings often requires complex internal cavity structures to meet specific functional requirements. These internal cavity structures are formed during the casting process, and in the finished castings, some cavities may need to be closed to ensure the integrity and functionality of the casting.

[0003] The plugging of complex inner cavity and irregular shaped channels of castings is a key step in the casting manufacturing process. These channels usually have irregular shapes and sizes, which brings great challenges to the plugging work. Traditional plugging methods mainly rely on brazing technology, which is a connection technology that connects two or more metal surfaces by melting brazing (a filler metal). The application of brazing in casting plugging is mainly to ensure the local functional integrity of castings, prevent liquid or gas leakage, and improve the pressure bearing capacity of castings. However, the existing brazing technology has some significant problems when dealing with complex inner cavity and irregular shaped channels. First, the accessibility of the brazing material is extremely poor, which means that during the plugging process, it is difficult to evenly fill the brazing material into every part of the channel, especially those narrow or curved areas. Secondly, due to the irregular characteristics of the channel, the assembly of the plugging material becomes extremely difficult, requiring precise operation and high skills. In addition, due to the complexity of these operations, brazing welds often have defects such as large-sized holes and leaky welds that are not tightly sealed. These problems not only affect the sealing of castings, but may also reduce the strength and durability of castings.

[0004] To this end, the inventors provide a method for sealing special-shaped channels in complex inner cavities of castings, which can improve the accessibility of brazing filler metal, reduce the difficulty of assembly, and increase the yield of brazing sealing, thereby gaining an advantage in the highly competitive manufacturing market. In addition, it may also promote the development of casting design and manufacturing technology, and provide the possibility for the production of more complex and higher performance castings. Summary of the invention

[0005] In view of the problems existing in the above-mentioned existing methods for plugging special-shaped channels in complex inner cavities of castings, the present invention is proposed.

[0006] Therefore, the present invention provides a method for sealing complex inner cavity and special-shaped channels of castings, and its purpose is to invent a method for sealing complex inner cavity and special-shaped channels of castings to improve the accessibility of solder and reduce the difficulty of assembly, and to improve the yield of brazing and sealing complex inner cavity and special-shaped channels of investment castings.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: comprising:

[0008] One end of the spherical plugging bead is ground flat to form a plane, and the assembly traction cord is spot welded on the ground plane of the bead;

[0009] Use adhesive tape solder to wrap a circle along the diameter direction parallel to the flattened end face of the spherical plugging material bead;

[0010] The ball-shaped plugging material bead is sent to the position to be brazed by assembling the traction soft wire, so that the assembling traction soft wire runs through the inner cavity of the casting corresponding to the entire channel to be blocked;

[0011] By assembling a traction cord to drag the spherical plugging material bead, the adhesive tape brazing material in the area to be brazed fits with the inner cavity surface of the casting and the spherical plugging material bead;

[0012] The spot-welded assembly traction cord is pulled off, and the casting is moved to a vacuum brazing furnace for brazing, thereby obtaining a casting with the inner cavity special-shaped channel blocked.

[0013] As a preferred solution of the method for plugging special-shaped channels in complex inner cavities of castings described in the present invention, the thickness of the spherical plugging beads after grinding is 0.4-1.2 mm.

[0014] As a preferred solution of the method for plugging special-shaped channels in the complex inner cavity of a casting according to the present invention, the diameter difference between the channels in the inner cavity of the casting and the spherical plugging beads is in the range of 0.1 to 0.2 mm.

[0015] As a preferred solution of the method for sealing the complex and irregular shaped channels in the inner cavity of a casting according to the present invention, the difference between the diameter of the assembly traction cord and the diameter of the narrowest area of ​​the inner cavity channel of the casting is in the range of 0.1 to 0.2 mm.

[0016] As a preferred solution of the method for sealing special-shaped channels in complex inner cavities of castings described in the present invention, the thickness of the adhesive solder is 0.05-0.1 mm.

[0017] As a preferred solution of the method for plugging special-shaped channels in complex inner cavities of castings described in the present invention, the width of the adhesive tape solder is 4 to 8 mm.

[0018] As a preferred solution of the method for sealing special-shaped channels in complex inner cavities of castings described in the present invention, the material of the assembly traction cord includes stainless steel, nickel-based alloy or glass fiber reinforced plastic.

[0019] As a preferred solution of the method for plugging special-shaped channels in complex inner cavities of castings described in the present invention, the material for spot welding includes copper, aluminum, silver or nickel-based alloy.

[0020] As a preferred solution of the method for sealing special-shaped channels in complex inner cavities of castings described in the present invention, the spot welding material can withstand a tensile force in the range of 10 to 60N to ensure that it will not break during the pulling process.

[0021] As a preferred solution of the method for sealing complex inner cavity and irregular shaped channels of castings described in the present invention, the spot welding connection can be disconnected when a force exceeding 70N is applied to ensure that the assembly traction cord is removed during the assembly process before brazing and does not affect the subsequent brazing process.

[0022] Beneficial effects of the present invention: The present invention adopts the method of sticky tape solder, which can accurately control the thickness and addition amount of the solder, making the addition of the solder more accurate, thereby ensuring the uniformity and quality of the welded joint. Compared with traditional paste or powder solder, the use of sticky tape solder reduces solder waste, improves the controllability of the welding process, and also reduces the risk of welding defects caused by excessive or insufficient solder.

[0023] The present invention uses spherical beads and assembly traction cords. The design of the spherical beads makes it easier to adapt to the irregular shape of the channel, and the traction cord assists in placing the beads accurately at the desired brazing position. This assembly method not only improves the accessibility of the solder, but also reduces the difficulty of overall assembly, allowing operators to complete the blocking task more quickly and accurately, thereby improving production efficiency and welding quality. By dragging the traction cord, the pre-filled solder between the inner cavity surface of the casting, the adhesive solder and the spherical beads can be compacted more tightly, which helps to eliminate the air gap between the solder and the casting, ensure good contact between the solder and the casting surface, thereby improving the strength and sealing of the brazing joint, while reducing defects such as holes and cracks in the welding process, further improving the welding quality.

[0024] As an auxiliary tool, the traction wire can be easily disassembled after the brazing material is filled, which will not affect the subsequent brazing process, greatly simplifying the entire plugging process. In addition, due to the auxiliary role of the traction wire, the operation of the entire assembly process becomes more convenient, reducing the requirements for operator skills, improving the feasibility and applicability of the method, and also helping to reduce errors and rework in production, thereby reducing costs and improving production efficiency.

[0025] In summary, the present invention not only improves the quality and efficiency of sealing complex inner cavity special-shaped channels of castings, but also provides a more reliable, economical and environmentally friendly solution for the casting manufacturing field through innovative design and methods, which can further promote the development of casting manufacturing technology and meet the needs of higher performance castings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 It is a schematic assembly diagram of the method for sealing special-shaped channels in complex inner cavities of castings according to the present invention.

[0028] Figure 2 This is a schematic diagram of the brazing interface structure in Example 1 of the present invention.

[0029] Figure 3 This is a schematic diagram of the brazing interface structure in Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it an embodiment that is mutually exclusive with other embodiments, either individually or selectively.

[0033] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0034] Example 1, reference Figure 1 , which is the first embodiment of the present invention, provides a method for plugging a casting complex inner cavity irregular channel, comprising:

[0035] One end of the spherical plugging bead is ground flat to form a plane, and the assembly traction cord is spot welded on the ground plane of the bead. By grinding one end of the bead to form a plane, the stability and reliability of spot welding can be ensured. The spot welding assembly traction cord on this plane provides a fixed and reliable connection point for subsequent traction and positioning of the bead.

[0036] Use adhesive tape brazing material to wrap a circle along the diameter direction parallel to the flattened end face of the spherical plugging material bead, which provides the necessary brazing material for the brazing process;

[0037] The ball-shaped plugging beads are sent to the position to be brazed by assembling the traction cord, and the assembling traction cord runs through the entire inner cavity of the casting corresponding to the channel to be blocked. The traction cord is used to accurately guide the ball-shaped plugging beads to the position to be brazed. Through the traction cord, the staff can control the movement of the beads to ensure that they can smoothly pass through the inner cavity of the casting and reach the channel to be blocked;

[0038] By assembling a traction cord to drag the spherical plugging beads, the adhesive tape solder in the area to be brazed fits with the inner surface of the casting and the spherical plugging beads. By dragging the traction cord, the adhesive tape solder is more closely in contact with the inner surface of the casting and the spherical plugging beads, ensuring that the solder can form a good metallurgical bond during the brazing process, thereby improving the strength and sealing of the brazed joint.

[0039] The spot welding assembly traction soft wire is pulled off, and the casting is moved to the vacuum brazing furnace for brazing, that is, the casting with the inner cavity special-shaped channel sealed is obtained. The spot welding traction soft wire is pulled off, and the auxiliary tools are removed to prepare for the brazing process, ensuring that the casting is brazed under high temperature and protective atmosphere, thereby obtaining high-quality brazing joints and sealing effects.

[0040] Among them, the thickness of the spherical sealing beads is ground to 0.8mm, which ensures that the force distribution is more even when the traction wire is dragging the spherical sealing beads, reduces local stress concentration, and avoids damage to the beads or traction wires due to uneven force.

[0041] Specifically, the diameter difference between the inner cavity channel of the casting and the spherical plugging beads is in the range of 0.1 mm, which ensures the positioning and movement of the beads in the inner cavity while reducing the friction and damage of the beads when moving in the channel.

[0042] Furthermore, the difference between the diameter of the assembled traction wire and the diameter of the narrowest area of ​​the casting inner cavity channel is 0.1mm. The traction wire can smoothly pass through the narrowest area of ​​the casting inner cavity channel, while ensuring that no excessive swing or deviation occurs during operation, thereby improving the accuracy of blocking.

[0043] Furthermore, the thickness of the adhesive tape solder used was 0.05 mm and the width was 5 mm, which provided an appropriate amount of solder and helped to form a uniform and high-strength brazed joint.

[0044] Furthermore, the materials for assembling the traction cord and spot welding are glass fiber reinforced plastic and nickel-based alloy respectively. This combination can maintain performance during brazing and reduce the risk of failure. The lightness of glass fiber reinforced plastic and the easy-disconnection characteristics of nickel-based alloy make operation more convenient and improve work efficiency.

[0045] The casting after brazing of this embodiment was cut and tested, and the results are shown in the attached Figure 2 As shown, there are no visible defects in the brazed joint, such as holes, cracks or unfused areas, which indicates that the brazing process is very successful. This is because the present invention adopts the method of sticky tape brazing, which can accurately control the thickness and amount of brazing material, making the addition of brazing material more accurate, thereby ensuring the uniformity and quality of the welded joint, and the use of sticky tape brazing material reduces brazing material waste, improves the controllability of the welding process, and also reduces the risk of welding defects caused by excessive or insufficient brazing material.

[0046] The present invention uses spherical beads and assembly traction cords. The design of the spherical beads makes it easier to adapt to the irregular shape of the channel, and the traction cord assists in placing the beads accurately at the desired brazing position. This assembly method not only improves the accessibility of the solder, but also reduces the difficulty of overall assembly, allowing operators to complete the blocking task more quickly and accurately, thereby improving production efficiency and welding quality. By dragging the traction cord, the pre-filled solder between the inner cavity surface of the casting, the adhesive solder and the spherical beads can be compacted more tightly, which helps to eliminate the air gap between the solder and the casting, ensure good contact between the solder and the casting surface, thereby improving the strength and sealing of the brazing joint, while reducing defects such as holes and cracks in the welding process, further improving the welding quality.

[0047] Comparative Example 1

[0048] Comparative Example 1 provides a conventional brazing method using truncated cone plugging beads filled with paste solder, specifically:

[0049] Select appropriate truncated cone plugging beads, the diameter of which is slightly smaller than or equal to the diameter of the inner cavity of the casting;

[0050] Filling the paste solder into the inner cavity of the casting;

[0051] Place the truncated cone plugging bead at one end of the inner hole of the casting, ensuring that the bead can adapt to the shape of the hole and remain stable during the brazing process;

[0052] The casting is placed in a brazing furnace to obtain a casting with the special-shaped pores in the inner cavity blocked.

[0053] The casting after brazing of Comparative Example 1 was cut and tested, and the results are shown in the attached Figure 3As shown, it can be seen that there are large-area hole defects in the brazing interface structure. This is caused by uneven distribution of the brazing material and poor contact between the sealing beads and the inner cavity of the casting. The poor contact between the sealing beads and the inner cavity of the casting will affect the sealing and strength of the casting. The poor contact is due to the fact that the shape of the truncated cone sealing beads is not suitable for the shape of the inner cavity of the casting.

[0054] The present invention not only improves the quality and efficiency of sealing the complex inner cavity special-shaped channels of castings, but also provides a more reliable, economical and environmentally friendly solution for the casting manufacturing field through innovative design and methods, which can further promote the development of casting manufacturing technology and meet the needs of higher performance castings.

[0055] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to several modifications still falling within the scope of the appended claims.

[0056] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0057] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for plugging special-shaped channels in complex inner cavities of castings, characterized by: include, One end of the spherical plugging bead is ground flat to form a plane, and the assembly traction cord is spot welded on the ground plane of the bead; Use adhesive tape solder to wrap a circle along the diameter direction parallel to the flattened end face of the spherical plugging material bead; The ball-shaped plugging material bead is sent to the position to be brazed by assembling the traction soft wire, so that the assembling traction soft wire runs through the inner cavity of the casting corresponding to the entire channel to be blocked; By assembling a traction cord to drag the spherical plugging material bead, the adhesive tape brazing material in the area to be brazed fits with the inner cavity surface of the casting and the spherical plugging material bead; The spot-welded assembly traction cord is pulled off, and the casting is moved to a vacuum brazing furnace for brazing, thereby obtaining a casting with the inner cavity special-shaped channel blocked.

2. The method for plugging special-shaped channels in complex inner cavities of castings according to claim 1, characterized in that: The spherical plugging material beads have a grinding thickness of 0.4 to 1.2 mm.

3. The method for plugging special-shaped channels in complex inner cavities of castings according to claim 2, characterized in that: The diameter difference between the inner cavity channel of the casting and the spherical plugging beads ranges from 0.1 to 0.2 mm.

4. The method for plugging special-shaped channels in complex inner cavities of castings according to claim 3, characterized in that: The difference between the diameter of the assembly traction soft wire and the diameter of the narrowest area of ​​the inner cavity channel of the casting is in the range of 0.1 to 0.2 mm.

5. The method for plugging special-shaped channels in complex inner cavities of castings according to claim 4, characterized in that: The thickness of the adhesive tape solder is 0.05-0.1 mm.

6. The method for plugging special-shaped channels in complex inner cavities of castings according to claim 5, characterized in that: The width of the adhesive tape solder is 4 to 8 mm.

7. The method for plugging special-shaped channels in complex inner cavities of castings according to claim 6, characterized in that: The material of the assembled traction cord includes stainless steel, nickel-based alloy or glass fiber reinforced plastic.

8. The method for plugging special-shaped channels in complex inner cavities of castings according to claim 7, characterized in that: The material for the spot welding includes copper, aluminum, silver or nickel-based alloy.

9. The method for plugging special-shaped channels in complex inner cavities of castings according to claim 8, characterized in that: The spot welding connection can withstand a tensile force in the range of 10 to 60 N to ensure that it will not break during the pulling process.

10. The method for plugging special-shaped channels in complex inner cavities of castings according to claim 9, characterized in that: The spot welding connection can be disconnected when a force exceeding 70N is applied, so as to ensure that the assembly traction cord is removed during the assembly process before soldering, without affecting the subsequent soldering process.

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