Casting system for eliminating casting shrinkage cavity defect in eccentric bushing casting
By optimizing the design of the casting system and adopting a combination of risers, chills, and gating systems, the shrinkage defect in eccentric sleeve castings was solved, and sequential solidification and quality improvement of the castings were achieved.
Patent Information
- Application Number
- CN202422574915.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-24
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-10-24
AI Technical Summary
In the existing resin sand eccentric sleeve casting process, the castings are prone to shrinkage defects, which are difficult to completely eliminate using conventional chilling processes, affecting the casting quality and surface quality.
Design a casting system including risers, cavities, sand cores, and a gating system. Employ a fully bottom-casting method, combining a stepped structure of first and second chills with multiple risers to optimize the cooling and solidification sequence of the casting. By coordinating the risers and chills, control the temperature field of the casting to ensure sequential solidification.
It effectively eliminates shrinkage cavities and porosity defects inside castings, improves casting quality and yield, and enhances the mechanical properties of castings.
Smart Images
Figure CN223492008U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of casting technology, and in particular to a casting system for eliminating shrinkage defects in castings during eccentric sleeve casting. Background Technology
[0002] Casting is a production method that involves forming molten metal into a mold. The process of molten metal entering a mold, cooling, and solidifying to form a metal product is called casting. The produced metal product is called a casting. In the casting process, designers discovered that a type of eccentric sleeve casting, due to uneven wall thickness leading to inconsistent cooling rates, was difficult to solidify sequentially, resulting in shrinkage cavities inside the casting. The production of this type of eccentric sleeve casting requires high precision; the finished casting needs to undergo magnetic particle testing on its outer surface and ultrasonic testing on its interior to check its quality.
[0003] For shrinkage cavities, conventional chill processes can only reduce the size of the hot spot at the shrinkage cavity or transfer the hot spot, but cannot completely eliminate the defect. Increasing the number of chills to eliminate shrinkage cavities can easily lead to surface defects in the casting. Therefore, designers need to design a method to solve the shrinkage cavities that occur in castings during existing resin sand eccentric sleeve casting processes, thereby improving the quality of the castings. Utility Model Content
[0004] The technical problem solved by this utility model is to design a casting system that can solve the shrinkage cavity defect in castings that occurs in the existing resin sand eccentric sleeve casting process, thereby improving the quality of castings.
[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:
[0006] A casting system for eliminating shrinkage defects in castings during eccentric sleeve casting includes: riser, mold cavity, sand core, and gating system;
[0007] The riser is located on the top of the cavity;
[0008] The sand core is located inside the cavity;
[0009] A first chill is provided on the outside of the sand core;
[0010] A second chill is provided outside the cavity;
[0011] The casting system employs a fully bottom-casting method.
[0012] Preferably, the casting system includes a sprue passage, a ring gating passage, and a branch gating passage; the sprue passage is located above the ring gating passage.
[0013] A gating gate is provided on the direct gating channel;
[0014] One end of the gating channel is connected to the ring gating channel, and the other end is connected to the bottom of the cavity.
[0015] Preferably, the first chill has a stepped structure and fits into the outer wall of the sand core.
[0016] Preferably, the second chill is arranged in a ring around the side of the cavity.
[0017] Preferably, the riser includes a small riser and a large riser, and the positions of the small riser and the large riser are determined according to the eccentric position of the eccentric sleeve casting.
[0018] Preferably, the gating channel has multiple passages.
[0019] Preferably, multiple risers are provided.
[0020] The beneficial effects of this utility model are:
[0021] This invention relates to a casting system for eliminating shrinkage cavities in eccentric sleeve casting. It solves the problems of shrinkage cavities and porosity in existing resin sand eccentric sleeve casting processes, thereby improving the quality, yield, and mechanical properties of the eccentric sleeve castings. The system improves the solidification sequence of the casting body through the use of large and small risers and the first and second chills, ensuring that the casting solidifies sequentially according to a specific process. The first chill employs a stepped wall thickness design to alter the cooling and solidification sequence of the casting body, creating an increasing temperature field. This ensures that areas far from the riser solidify first, gradually moving towards the riser. The riser uses a heat-generating and insulating riser to maintain the temperature field at the upper end of the casting, transferring the final heat points to the riser and thus ensuring the quality of the casting. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the structure of a casting system for eliminating shrinkage defects in castings during eccentric sleeve casting, according to this utility model.
[0023] Figure 2 This is another schematic diagram of the casting system shown;
[0024] Figure 3 This is a schematic cross-sectional view of the casting system shown.
[0025] Figure 4 This is a schematic diagram of the first chill with a stepped structure in the casting system.
[0026] The components in the attached diagram are labeled as follows:
[0027] 1. Mold cavity; 2. Sand core; 3. First chill; 4. Second chill; 5. Gate; 6. Sprue passage; 7. Ring runner passage; 8. Sprue passage; 9. Small riser; 10. Large riser. Detailed Implementation
[0028] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of the present invention.
[0029] Example:
[0030] This embodiment describes a casting system for eliminating shrinkage defects in eccentric sleeve casting, such as... Figure 1 , 2 As shown in Figure 3; Figure 1 This is a schematic diagram of the structure of a casting system for eliminating shrinkage defects in eccentric sleeve casting according to this utility model. Figure 2 This is another schematic diagram of the casting system shown. Figure 3 This is a schematic cross-sectional view of the casting system shown.
[0031] A casting system for eliminating shrinkage defects in eccentric sleeve casting includes a riser, a mold cavity 1, a sand core 2, and a casting system; the riser is located on the top of the mold cavity 1; the sand core 2 is located inside the mold cavity 1, and a first chill 3 is provided outside the sand core 2; a second chill 4 is provided outside the mold cavity 2.
[0032] In this embodiment, the mold cavity and the second chill are machined as a single unit according to the requirements for casting the eccentric sleeve; that is, the second chill is fixed to the outer wall of the mold cavity. The first chill is fixed together with the sand core. The chills close to the inner and outer walls of the mold cavity serve to cool the molten iron being poured.
[0033] The casting system adopts a fully bottom-pouring method. In this embodiment, the casting material of the eccentric sleeve is QT500-7, and the casting process adopts a fully bottom-pouring method. This method ensures stable filling during the pouring process and reduces the occurrence of secondary slag.
[0034] Furthermore, the casting system includes a sprue passage 6, a ring gating passage 7, and a branch gating passage 8; the sprue passage 6 is located above the ring gating passage 7; a gate 5 is provided on the sprue passage 6; one end of the branch gating passage 8 is connected to the ring gating passage 7, and the other end is connected to the bottom of the mold cavity 2. In this embodiment, multiple branch gating passages 8 are provided. The gate is used to pour in molten iron, which enters the ring gating passage through the sprue passage, and then enters the mold cavity through the multiple branch gating passages.
[0035] like Figure 4As shown, Figure 4 This is a schematic diagram of the first chill with a stepped structure in the casting system. The inner wall of the first chill 3 has a stepped structure and matches the outer wall of the sand core 2.
[0036] The first chill 3 adopts a stepped wall thickness design to change the cooling and solidification sequence of the casting body, creating an increasing temperature field for the casting. This ensures that the casting solidifies preferentially in areas far from the riser, gradually moving towards the riser. The riser uses a heat-generating and heat-insulating riser to maintain the temperature field at the upper end of the casting, transferring the last heat point of the casting to the riser, thereby ensuring the quality of the casting. Finally, the riser itself solidifies, and liquid feeding is performed on the solidified area of the last riser to solve the shrinkage cavity defect.
[0037] like Figure 1 As can be seen above, the second chill 4 is arranged in a ring around the side of the cavity 2, and is offset according to the eccentric position of the eccentric sleeve casting.
[0038] Furthermore, the riser includes a small riser 9 and a large riser 10. Multiple risers are provided; in this embodiment, four small risers and one large riser are provided, and the positions of the small riser 9 and the large riser 10 are determined according to the eccentric position of the eccentric sleeve casting.
[0039] For ease of understanding, combined with Figure 1 This section explains how the small riser and large riser are determined based on the eccentric position of the eccentric sleeve casting. In this embodiment, the eccentric requirements of the eccentric sleeve casting are known before casting. Therefore, in the casting system designed in this utility model, the mold cavity is eccentrically designed, and the second chill 4 is eccentrically designed on the outer wall of the mold cavity, thus forming the eccentric position of the casting, and thus forming the... Figure 1 The above illustration shows the effect. Under the aforementioned conditions, the mold cavity will form internal cavity areas of different sizes, resulting in different amounts of molten iron entering during casting. At this time, the small riser is set in the position of the small area of the mold cavity, and the large riser is set in the position of the large area of the mold cavity. By setting large and small risers, shrinkage cavities are eliminated through feeding, thereby improving the casting quality of the eccentric sleeve casting.
[0040] The casting system provided by this utility model, which eliminates shrinkage defects in eccentric sleeve casting, can solve the shrinkage and porosity defects inside the castings in the existing resin sand eccentric sleeve casting process, thereby improving the quality of eccentric sleeve castings, increasing the yield, and improving the mechanical properties of the castings.
[0041] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.
Claims
1. A casting system for eliminating shrinkage defects in eccentric sleeve casting, characterized in that, include: Riser, cavity (1), sand core (2), casting system; The riser is located on the top of the cavity (1); The sand core (2) is located inside the cavity (1); The sand core (2) is provided with a first chill (3) on its outside; A second chill (4) is provided outside the cavity (1); The casting system employs a fully bottom-casting method.
2. The casting system for eliminating shrinkage defects in eccentric sleeve casting according to claim 1, characterized in that: The casting system includes a sprue passage (6), a ring gating passage (7), and a branch gating passage (8); the sprue passage (6) is located above the ring gating passage (7); A gating gate (5) is provided on the direct gating channel (6); One end of the gating channel (8) is connected to the ring gating channel (7), and the other end is connected to the bottom of the cavity (1).
3. The casting system for eliminating shrinkage defects in eccentric sleeve casting according to claim 1, characterized in that: The first chill (3) adopts a stepped structure and is matched with the outer wall of the sand core (2).
4. The casting system for eliminating shrinkage defects in eccentric sleeve casting according to claim 1, characterized in that: The second chill (4) is arranged in a ring around the side of the cavity (1).
5. A casting system for eliminating shrinkage defects in eccentric sleeve casting according to claim 1, characterized in that: The riser includes a small riser (9) and a large riser (10), and the positions of the small riser (9) and the large riser (10) are determined according to the eccentric position of the casting eccentric sleeve.
6. A casting system for eliminating shrinkage defects in eccentric sleeve casting according to claim 2, characterized in that: The gating channel (8) has multiple channels.
7. A casting system for eliminating shrinkage defects in eccentric sleeve casting according to claim 1, characterized in that: The number of risers is set to multiple.