A multi-layer gating device for investment casting
By designing a multi-layer casting device, the problems of molten metal flow and solidification in complex castings by traditional casting systems are solved, achieving high-quality casting and improving the yield.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XIAN HAOSEN PRECISION CASTING
- Filing Date
- 2025-07-02
- Publication Date
- 2026-06-30
AI Technical Summary
Traditional gating systems struggle to precisely control the flow state and solidification sequence of molten metal in complex castings, leading to porosity and shrinkage defects in concave corner areas. Furthermore, the lack of a directional feeding mechanism results in mold shell breakage and low forming quality.
A multi-layer casting device is designed, including multiple risers, top and bottom horizontal runners, straight runners and ingates. By layered casting and multi-point casting, the filling behavior of molten metal is optimized, the local feeding capacity is enhanced and the temperature field distribution is improved.
It improves the forming quality of complex castings, reduces porosity and shrinkage defects, enhances the local feeding effect, and increases the yield.
Smart Images
Figure CN224424198U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of metal investment casting technology, and in particular relates to a multi-layer pouring device for investment casting. Background Technology
[0002] In investment casting, the forming quality of complex castings (such as parts with deep concave corners, narrow grooves, or non-uniform wall thickness) is often limited by local defects. This is particularly evident in concave corner areas and thin / thick wall transition zones, where solidification defects such as porosity and shrinkage cavities are prone to occur. Analysis reveals that the root causes can be attributed to the following two aspects:
[0003] 1) Insufficient filling capacity: When the molten metal flows through the concave corner area with a complex structure, the flow velocity is significantly reduced due to the increased flow resistance, causing local solidification to occur first in this part, blocking the feeding channel of the subsequent molten metal.
[0004] 2) Solidification thermodynamic imbalance: The heat dissipation rate of thin-walled areas is higher than that of thick-walled areas, causing concave corners to become hot nodes at the end of solidification. Due to the lack of effective directional feeding paths, these areas cannot obtain sufficient molten metal compensation during the solidification shrinkage stage, eventually forming shrinkage cavities or microporous structures.
[0005] Traditional gating systems typically employ a single-entry sprue-runner-ingate series structure. This design has significant limitations:
[0006] 1) It is difficult to accurately control the flow state and solidification sequence of molten metal in the concave corner area of irregular castings. Due to the difference in wall thickness, the concave corner area is not conducive to feeding. The feeding of a single gating system is insufficient to form a bottom-up solidification sequence. The concave corner has poor heat dissipation and slow cooling, resulting in shrinkage cavities and porosity in the concave corner.
[0007] 2) The lack of a directional feeding mechanism for local hot nodes leads to insufficient static pressure of the molten metal in the defect area, which can easily cause more than 30% of the mold shell to break and be scrapped, resulting in serious economic losses.
[0008] 3) The overall casting scheme cannot coordinate the solidification synergy between thin-walled and thick-walled areas, resulting in a consistently low pass rate for concave corner areas (usually less than 70%).
[0009] Therefore, there is an urgent need to develop a new type of casting device that can optimize the filling behavior of molten metal in complex structures, enhance local feeding capabilities, and improve temperature field distribution. Utility Model Content
[0010] To address the aforementioned technical problems, this utility model provides a multi-layer casting device for investment casting, which solves the problems through the following technical means:
[0011] A multi-layer gating device for investment casting is characterized by comprising risers, a top horizontal sprue, a top inner gate, a sprue, a bottom horizontal sprue, and a bottom inner gate, wherein: multiple top horizontal sprues intersect symmetrically in a horizontal state; multiple risers are symmetrically installed on the top of the top horizontal sprues; a top inner gate is provided at the bottom of the outer end of each top horizontal sprue; a sprue is vertically connected downwards at the intersection of the middle of multiple top horizontal sprues; the bottom of the sprue is vertically connected to one or more bottom horizontal sprues, and a bottom inner gate is provided at the bottom of the outer end of the bottom horizontal sprue.
[0012] Preferably, the number of risers is three or five.
[0013] Preferably, the number of the top-level horizontal gating channels is two, three, or four.
[0014] Preferably, when the bottom of the direct pouring channel is vertically connected to a bottom horizontal pouring channel, the direct pouring channel is connected to the center of the bottom horizontal pouring channel.
[0015] Preferably, when the bottom of the straight gating channel is vertically connected to multiple bottom horizontal gating channels, the number of bottom horizontal gating channels is two, three, or four, and the multiple bottom horizontal gating channels intersect symmetrically in a horizontal state.
[0016] Preferably, reinforcing ribs connect the plurality of risers.
[0017] Preferably, the special-shaped casting for casting includes a top perforated circular plate and a bottom circular ring arranged coaxially. The top perforated circular plate and the bottom circular ring are connected by multiple inclined connecting ribs. The top perforated circular plate extends outward on one side to form a top boss, and the bottom circular ring extends outward on one side to form a bottom boss.
[0018] Preferably, the perforated circular plate at the top layer is cast by an ingate at the top layer, and the circular ring at the bottom layer is cast by an ingate at the bottom layer.
[0019] The multi-layer casting device for investment casting of this utility model has the following beneficial effects:
[0020] 1) Riser design: Multiple risers are designed above the gating system. During the pouring process, the molten metal is poured from the middle riser to provide molten metal to compensate for the shrinkage of the casting volume. In addition, the design of multiple risers can increase the venting channels, ensure that the gas can be discharged smoothly, better disperse and collect slag, and reduce slag inclusion defects inside the casting.
[0021] 2) Layered gating system design: A layered gating system is adopted, with each gating system connected to an ingate at its lower end. The two gating systems are directly connected by a sprue, which enables the molten metal to fully fill the upper and lower plates.
[0022] 3) Multi-point pouring: The main runner is connected to multiple gates through multiple branch runners, thus achieving simultaneous filling at multiple points. The upper horizontal runner connects to four ingates, providing sufficient feeding to the upper plate. At the same time, the molten metal flows through the sprue and stiffeners to the lower bottom plate, where two symmetrical ingates and two symmetrical stiffeners provide sufficient feeding to the lower bottom plate. Attached Figure Description
[0023] To more clearly illustrate the technical solution of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0024] Figure 1 is a schematic diagram of the overall structure of this utility model;
[0025] Figure 2 is a schematic diagram of the bottom structure of this utility model;
[0026] Figure 3 is a schematic diagram of the first application of this utility model;
[0027] Figure 4 is a schematic diagram of the second application of this utility model;
[0028] Figure 5 is a schematic diagram of the irregular casting structure of this utility model.
[0029] Among them, 1-riseer, 2-top horizontal runner, 3-top inner gate, 4-sprue, 5-bottom horizontal runner, 6-bottom inner gate, 7-reinforcing rib, 8-irregular casting, 801-top perforated circular plate, 802-bottom circular ring, 803-inclined connecting rib plate, 804-top boss, 805-bottom boss. Detailed Implementation
[0030] In the description of this utility model, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0031] The present invention will now be described in detail with reference to the accompanying drawings.
[0032] As shown in Figures 1 to 5, the multi-layer gating device for the investment casting includes risers 1, top sprues 2, top ingates 3, sprues 4, bottom sprues 5, and bottom ingates 6. In the figures: two top sprues 2 intersect vertically in a horizontal state; three risers 1 are symmetrically installed on the top of the top sprues 2; a top ingate 3 is provided at the bottom of the outer end of each top sprue 2; a sprue 4 is vertically connected downwards at the intersection of the middle parts of the top sprues 2; a bottom sprue 5 is vertically connected at the bottom of the bottom sprue 4; and a bottom ingate 6 is provided at the bottom of the outer end of the bottom sprue 5.
[0033] It should be noted that the number of risers 1 can be three or five, and the number of top-level horizontal runners 2 can be two, three, or four. The number of bottom-level horizontal runners 5 can also be multiple; for example, two bottom-level horizontal runners 5 can be arranged perpendicularly to each other.
[0034] In practical applications, multiple risers 1 are connected by reinforcing ribs 7.
[0035] It should be noted that the casting for the irregular-shaped part 8 includes a top perforated circular plate 801 and a bottom circular ring 802 arranged coaxially. The top perforated circular plate 801 and the bottom circular ring 802 are connected by multiple inclined connecting ribs 803. The top perforated circular plate 801 extends outward on one side to form a top boss 804, and the bottom circular ring 802 extends outward on one side to form a bottom boss 805. Specifically, the casting product mainly consists of two circular plates and two connecting ribs. Due to the difference in wall thickness, the concave corner at the connection between the ribs and the bottom plate has poor heat dissipation, resulting in porosity. When using traditional methods, the concave corner area is prone to porosity and shrinkage defects due to insufficient filling of molten metal or insufficient solidification and feeding. The layered casting and multi-point casting combination design can eliminate porosity at the concave corner.
[0036] During actual casting, the perforated circular plate 801 at the top is poured through the top ingate 3, and the circular ring 802 at the bottom is poured through the bottom ingate 6. In this design, multiple risers are designed above the gating system. During casting, molten metal is poured from the middle riser to compensate for the shrinkage of the casting volume. Furthermore, the multiple risers increase venting channels, ensuring smooth gas discharge, better dispersion and collection of slag, and reducing inclusion defects inside the casting. In addition, a layered runner system is used, with each runner connected to an ingate at its lower end. Two runners are directly connected by a sprue, ensuring sufficient filling of the upper and lower plates with molten metal. Secondly, the main runner connects to multiple gates through multiple branch runners, enabling simultaneous filling at multiple points. The upper runner connects to four ingates, providing sufficient feeding to the upper plate. Simultaneously, the molten metal flows along the sprue and ribs to the lower bottom plate, where two symmetrical ingates and two symmetrical ribs provide sufficient feeding to the lower bottom plate.
[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model 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. Such 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 this utility model.
Claims
1. A multiple layer pouring apparatus for investment castings, characterized by, It includes riser (1), top horizontal runner (2), top ingate (3), sprue (4), bottom horizontal runner (5), and bottom ingate (6), wherein: Multiple top-level horizontal gating channels (2) intersect symmetrically in a horizontal manner; Multiple risers (1) are symmetrically installed on the top of the top horizontal gating (2); Each top-level horizontal gating (2) has a top-level inner gating (3) at the bottom of its outer end; At the intersection of the middle parts of multiple top-level horizontal sprues (2), vertical sprues (4) are connected downwards. The bottom of the sprue (4) is vertically connected to one or more bottom runners (5), and the bottom of the outer end of the bottom runner (5) is provided with a bottom inlet (6).
2. The multiple layer pouring apparatus for investment castings according to claim 1, wherein The number of risers (1) is three or five.
3. The multiple layer pouring apparatus for investment castings of claim 1 wherein, The number of the top-level horizontal gating (2) is two, three, or four.
4. The multiple layer pouring apparatus for investment castings of claim 1 wherein, When the bottom of the sprue (4) is vertically connected to a bottom horizontal sprue (5), the sprue (4) is connected to the center of the bottom horizontal sprue (5).
5. The multiple layer pouring apparatus for investment castings of claim 1 wherein, When the bottom of the straight gating channel (4) is vertically connected to multiple bottom horizontal gating channels (5), the number of bottom horizontal gating channels (5) is two, three or four, and the multiple bottom horizontal gating channels (5) intersect symmetrically in a horizontal state.
6. The multiple layer pouring apparatus for investment castings of claim 1 wherein, Reinforcing ribs (7) are connected between the multiple risers (1).
7. The multiple layer pouring apparatus for investment castings of claim 1 wherein, The special-shaped casting (8) for casting includes a top perforated circular plate (801) and a bottom circular ring (802) arranged coaxially. The top perforated circular plate (801) and the bottom circular ring (802) are connected by multiple inclined connecting ribs (803). The top perforated circular plate (801) extends outward to one side to form a top boss (804), and the bottom circular ring (802) extends outward to one side to form a bottom boss (805).
8. The multiple layer pouring apparatus for investment castings of claim 7 wherein, The perforated circular plate (801) on the top layer is cast by the top layer ingate (3), and the circular ring (802) on the bottom layer is cast by the bottom layer ingate (6).