High-pressure casting runner system for large-area hollow structural member
By optimizing the positions of the main runner and ingate in the high-pressure casting gating system, and combining them with slag pockets and corrugated venting plates, the forming defects of deep-cavity, large-area hollow structural parts were solved, achieving efficient and high-quality die casting.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHONGQING YUJIANG LANFENG POWERPARTS CO LTD
- Filing Date
- 2025-05-27
- Publication Date
- 2026-05-12
AI Technical Summary
In the prior art, when the symmetrical gating system is applied to die castings with deep cavities and large-area hollow structures, it is easy to cause uneven temperature convergence of the molten metal, forming seams or cracks, which affects the molding quality, and the discontinuous flow path leads to a loose structure.
Design a high-pressure casting gating system for large-area hollow structural parts. The main gating is set on one side of the forming cavity, and the inner gate is set at the bottom of the outer peripheral surface. Combined with slag pot and wave-shaped venting plate, the flow path of molten metal is optimized to avoid temperature differences and flow resistance, and to ensure that molten metal is gradually and uniformly filled.
It effectively avoids molding defects caused by temperature differences at the junction of molten metal, improves molding quality and efficiency, reduces casting defects, simplifies mold structure and reduces costs.
Smart Images
Figure CN224222703U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of high-pressure die casting, specifically to a high-pressure die casting gating system for large-area hollow structural parts. Background Technology
[0002] High-pressure casting, as a highly efficient and precise metal forming process, has been widely used in numerous fields. From automotive parts manufacturing to the production of precision components in the aerospace industry, high-pressure casting plays an irreplaceable role due to its advantages such as rapid prototyping of complex structures and high dimensional accuracy and surface quality.
[0003] The gating system in high-pressure casting is a crucial component guiding molten metal into the mold cavity during the high-pressure casting process. The gating system's runners are the channels through which the molten metal enters the mold cavity. Their function is to control the flow direction and speed of the molten metal, ensuring its smooth and orderly filling of the cavity and avoiding defects such as under-casting and cold shuts. A well-designed gating system can also reduce material waste, shorten the molding cycle, and protect the mold to extend its service life. In some traditional gating designs, a symmetrical gating layout is typically used to ensure uniform filling of the cavity by the molten metal. For example, the existing technology "A Die Casting Mold and Die Casting Method" (Publication No.: CN118455480B) utilizes a first and second gating system symmetrically positioned on both sides of the cavity. This allows for simultaneous injection of molten metal into the cavity, enabling the molten metal from both sides to converge at the center of the cavity. This shortens the metal's travel distance within the cavity and allows the molten metal to quickly fill the entire cavity in a short time, ensuring the molding quality of the die-cast product. However, the existing technology still has the following technical problems:
[0004] While existing symmetrical gating systems optimize molten metal filling to some extent, they present challenges when dealing with irregularly shaped die-cast parts, such as those with deep cavities and large-area openwork structures at the bottom. Due to variations in cavity size and filling resistance across different areas, the symmetrical gating system can cause the molten metal to flow faster in larger areas (e.g., the circumferential portion) and slower in smaller areas (e.g., the bottom with openwork structures). This uneven temperature drop at the point of convergence can lead to incomplete fusion, resulting in seams or cracks and filling defects. Furthermore, when filling the bottom of a deep cavity, the large openwork structure creates discontinuous flow paths and increased resistance, accelerating the temperature drop of the molten metal. This further increases the likelihood of poor filling, loose internal structure, and other problems at the point of convergence, severely impacting the overall quality of the die-cast part. Utility Model Content
[0005] This utility model provides a high-pressure casting gating system for large-area hollow structural parts, which can solve the problem that the gating system of existing die casting molds is prone to causing forming defects, loose internal structure, and reduced forming quality when applied to die casting parts with deep cavity structure and asymmetry.
[0006] This application provides the following technical solution: a high-pressure casting gating system for large-area hollow structural parts, including a fixed mold plate, a fixed mold core fixed in the middle of the fixed mold plate, a molding cavity set in the middle of the fixed mold core, a main gating system connected to one side of the molding cavity, a slag discharge section connected to the outer periphery of the molding cavity, and an exhaust section connected to the outside of the slag discharge section; the inner gate of the main gating system is set at the bottom of the outer periphery of the molding cavity; the molding cavity includes an integrally formed circular cavity and an irregular cavity, the center of the molding cavity and the irregular cavity is a deep cavity structure, and the bottom of the molding cavity and the irregular cavity is a hollow structure.
[0007] Beneficial effects:
[0008] 1. Optimize the flow path of molten metal and ensure molding quality. This solution places the main runner on one side of the molding cavity, and the ingate at the bottom of the molding cavity. The advantages of this are twofold: First, the single-sided main runner allows the molten metal to gradually cover the entire filling area of the molding cavity in a unidirectional manner, resulting in smaller temperature differences between the filling areas. Compared to existing technologies, this avoids the problem of seams forming at the junction due to temperature differences when molten metal from multiple runners on both sides of the molding cavity converges. Second, because the circumferential sidewalls of the molding cavity have a large volume space and only a few protrusions, the resistance to molten metal is low, and the filling speed is fast. In contrast, the more complex hollow structure at the bottom of the molding cavity provides greater resistance to molten metal, resulting in a slower filling speed relative to the molding cavity's overall size. The circumferential sidewalls fill more slowly, resulting in a temperature difference between the molten metal filling the circumferential sidewalls and the bottom of the molding cavity. If the ingate is not positioned properly, molding defects may occur at the point where the molten metal merges within the molding cavity. To avoid this possibility, this design places the ingate at the bottom of the outer circumferential surface of the molding cavity. This way, when the molten metal enters the molding cavity, it will first fill the circumferential sidewalls and then assist in filling the bottom. This results in minimal temperature loss of the molten metal after the circumferential sidewalls are quickly filled. When this portion of the molten metal merges with the molten metal at the bottom of the molding cavity, the temperature difference between the two is even smaller, thus avoiding the possibility of molding defects at the point where the molten metal merges and effectively ensuring the quality of the molding process.
[0009] 2. Ensuring minimum filling distance and improving die-casting efficiency. This solution places the ingate of the main runner at the bottom of the outer circumference of the molding cavity, which also saves filling time. For example, if the filling speed of the circumferential sidewalls of the molding cavity is fast, taking 20 milliseconds, and the filling speed of the bottom of the molding cavity is slow, taking 40 milliseconds, if the ingate is placed at the top of the molding cavity, the circumferential sidewalls will be filled first, followed by the bottom, taking a total of 60 milliseconds. However, with the ingate placed at the bottom of the molding cavity in this solution, the molten metal prioritizes filling both the circumferential sidewalls and assists in filling the bottom of the molding cavity in the initial time, and die-casting may be completed in 50 milliseconds. This ingate placement not only achieves the minimum filling distance but also optimizes the die-casting processing time, effectively improving die-casting efficiency.
[0010] Furthermore, the slag discharge section includes a slag bag disposed on the outer periphery of the molding cavity, and the slag bag has a hollow structure.
[0011] Beneficial effects: Initially, the molten metal entering the mold cools rapidly upon contact with the forming cavity, leading to contact with air and the formation of large amounts of oxide scale and inclusions, which can easily cause casting defects. Therefore, this solution incorporates a slag pocket on the circumferential outer side of the forming cavity. The molten metal initially entering the cavity carries oxide scale and inclusions into the slag pocket, preventing impurities from remaining in the forming cavity and causing casting defects, thus improving casting quality. Furthermore, after the die-cast part is formed, the slag pocket is removed to preserve the solid shape of the die-cast product, facilitating subsequent processing.
[0012] Furthermore, the exhaust section includes an exhaust plate located on the outside of the slag bag, and a connecting groove is provided between the exhaust plate and the slag bag for communication.
[0013] Beneficial effects: During high-pressure die casting, positive pressure is quickly formed inside the cavity due to the filling of molten metal. The exhaust plate can discharge air and coolant from the cavity when the molten metal fills the cavity, releasing the cavity pressure in real time, preventing the flow of molten metal from being obstructed due to air pressure accumulation, ensuring the smooth filling of the bottom hollow area, and reducing problems such as under-casting and flow marks.
[0014] Furthermore, the exhaust plate has a wavy shape.
[0015] Beneficial effects: The wave-shaped venting plate structure, through its non-linear channel design, causes the high-speed molten aluminum to collide multiple times with the undulating channel surface as it flows through the venting plate, thus changing its direction. This reduces the flow rate of the molten aluminum through kinetic energy loss, preventing it from flowing out of the mold too quickly and improving the quality of the casting.
[0016] Furthermore, the slag discharge section also includes a free slag bag disposed on the outer periphery of the molding cavity, the free slag bag not being connected to the exhaust plate.
[0017] Beneficial effects: The free slag bag is not connected to the venting plate, but it can still accommodate the molten metal carrying oxide scale and slag that initially enters the molding cavity, reducing the number of connecting grooves and venting plates, simplifying the mold structure, reducing costs, and ensuring the economic efficiency of mold design. Attached Figure Description
[0018] Figure 1 This is an isometric view of the present invention.
[0019] Figure 2 for Figure 1 Axonometric view after removing the fixed mold core. Detailed Implementation
[0020] The following detailed description illustrates the specific implementation method:
[0021] The markings in the accompanying drawings include: fixed mold core 1, venting plate 2, connecting groove 3, slag bag 4, irregular cavity 5, main runner 6, inner gate 601, circular cavity 7, free slag bag 8.
[0022] Example 1
[0023] like Figures 1 to 2 As shown, the high-pressure casting gating system for a large-area hollow structure includes a fixed mold plate, a fixed mold core 1 fixed in the middle of the fixed mold plate, a molding cavity located in the middle of the fixed mold core 1, a main gating 6 connected to one side of the molding cavity, a slag removal section connected to the outer periphery of the molding cavity, and an venting section connected to the outside of the slag removal section; the die-cast part is located inside the molding cavity. For ease of structural demonstration, Figure 1 The fixed mold plate has been omitted. Furthermore, since the main runner 6, molding cavity, slag removal section, connecting groove 3, and venting section are all cavity flow channels formed after the mold is closed, for ease of structural demonstration, Figure 1 The structure is represented by a solid casting after die casting, and the forming cavity is represented by the die casting after forming.
[0024] like Figure 1 and Figure 2 As shown, the molding cavity includes an integrally formed circular cavity 7 and an irregularly shaped cavity 5. The center of the circular cavity 7 and the irregularly shaped cavity 5 is a recessed deep cavity structure, and the bottom of the circular cavity 7 and the irregularly shaped cavity 5 is a hollow structure. The ingate 601 of the main runner 6 is located at the bottom of one side of the outer peripheral surface of the circular cavity 7 and the irregularly shaped cavity 5. In this embodiment, four ingates 601 are provided, and two are provided at the bottom of the outer peripheral surface of the circular cavity 7 and the irregularly shaped cavity 5 respectively.
[0025] like Figure 1 and Figure 2As shown, the slag removal section includes a slag bag 4 and a free slag bag 8 disposed on the outer periphery of the circular cavity 7 and the irregular cavity, respectively. Both the slag bag 4 and the free slag bag 8 are hollow structures. Since the molten metal initially entering the mold cools rapidly upon contact with the forming cavity, it comes into contact with the air in the mold, generating a large amount of oxide scale and inclusions, which can easily cause casting defects. Therefore, the molten metal initially entering the forming cavity is injected under high pressure, carrying oxide scale and inclusions into the slag bag 4 to prevent impurities from remaining in the forming cavity and causing forming defects, thus improving the forming quality. Furthermore, after the die casting is formed, the slag bag 4 is knocked off to preserve the solid shape of the die casting product, facilitating subsequent processing.
[0026] The venting section includes a venting plate 2 located outside the slag pot 4. The venting plate 2 is corrugated, and a connecting groove 3 connects the venting plate 2 and the slag pot 4. In this embodiment, the connecting groove 3 is also represented by a solid casting after die casting. The free slag pot 8 is not connected to the venting plate 2. To prevent the rapidly filling molten metal from directly rushing into the venting channel and causing the molten metal to splash too quickly, which may result in insufficient air removal in the forming cavity, leading to the formation of pores inside the die casting and affecting the die casting quality, the corrugated venting plate 2 can buffer the molten metal and effectively suppress molten metal splashing into the venting plate 2.
[0027] The method for using this solution is as follows:
[0028] After the mold is closed, the molten metal is injected under high pressure from the main runner 6, and then flows into the circular cavity 7 and the irregular cavity 5 through the four ingates 601, gradually filling the entire molding cavity. Then it enters the slag bag 4, the connecting groove 3 and the venting plate 2 in sequence before being discharged.
[0029] The advantages of this solution are as follows: Since the main gating system 6 is located on one side of the molding cavity and the ingate 601 is located at the bottom of the outer circumference of the molding cavity, the molten metal gradually covers the entire filling area of the molding cavity in a unidirectional manner. The temperature difference between the various filling parts is smaller. Compared to the symmetrical gating system of existing technologies, this solution avoids the problem of seams forming at the junction due to temperature differences when the molten metal from the two gating systems merges. Furthermore, due to the large volume of the circumferential sidewalls of the molding cavity, the molten metal fills quickly. The more complex hollow structure of the bottom surface of the molding cavity provides greater resistance to the molten metal, resulting in a slower filling speed compared to the circumferential sidewalls of the molding cavity. Therefore, there are differences in temperature changes between the circumferential sidewalls and the bottom of the molding cavity. If the ingate position is not set properly, molding defects may occur at the junction of the molten metal. To avoid the possibility of such defects, this solution sets the ingate at the bottom of the outer circumferential surface of the molding cavity. When the molten metal enters the molding cavity, it will first fill the circumferential sidewalls of the molding cavity and assist in filling the bottom of the molding cavity. After the circumferential sidewalls are quickly filled, the temperature loss of the molten metal is small. When this part of the molten metal merges with the molten metal at the bottom of the molding cavity, the temperature difference between the two is smaller, thus avoiding the possibility of molding defects at the junction of the molten metal and effectively ensuring the quality of molding.
[0030] This design places the ingate 601 of the main gating system 6 at the bottom of the molding cavity, which saves filling time. For example, if the filling speed of the circumferential sidewalls of the molding cavity is fast, taking 20 milliseconds, and the filling speed of the bottom of the molding cavity is slow, taking 40 milliseconds, if the ingate 601 is placed at the top of the molding cavity, the circumferential sidewalls will be filled first, followed by the bottom, taking a total of 60 milliseconds. However, with the ingate 601 placed at the bottom of the molding cavity, the molten metal prioritizes filling both the circumferential sidewalls and assists in filling the bottom of the molding cavity in the initial time, and the die casting may be completed in 50 milliseconds. This ingate placement not only achieves the minimum filling distance but also optimizes the die casting processing time, effectively improving die casting efficiency.
[0031] The above are merely embodiments of this utility model, and the utility model is not limited to the field covered by this embodiment. Commonly known structures and characteristics in the solutions are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications 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 high-pressure casting gating system for large-area hollow structural components, characterized in that: It includes a fixed mold plate, a fixed mold core fixed in the middle of the fixed mold plate, a molding cavity set in the middle of the fixed mold core, a main runner connected to one side of the molding cavity, a slag discharge section connected to the outer periphery of the molding cavity, and an exhaust section connected to the outside of the slag discharge section; the inner gate of the main runner is set at the bottom of the outer periphery of the molding cavity, and the molding cavity includes an integrally formed circular cavity and an irregular cavity, the center of the molding cavity and the irregular cavity is a deep cavity structure, and the bottom of the molding cavity and the irregular cavity is a hollow structure.
2. The high-pressure casting gating system for large-area hollow structural components according to claim 1, characterized in that: The slag discharge section includes a slag bag disposed on the outer periphery of the forming cavity, and the slag bag has a hollow structure.
3. The high-pressure casting gating system for large-area hollow structural components according to claim 2, characterized in that: The exhaust section includes an exhaust plate located on the outside of the slag bag, and a connecting groove is provided between the exhaust plate and the slag bag for communication.
4. The high-pressure casting gating system for large-area hollow structural components according to claim 3, characterized in that: The exhaust plate has a wavy shape.
5. The high-pressure casting gating system for large-area hollow structural components according to claim 2, characterized in that: The slag discharge section also includes a free slag bag disposed on the outer periphery of the molding cavity, and the free slag bag is not connected to the exhaust plate.