Valve casting part structure facilitating mold core positioning
By using soluble core seats and salt cores in valve castings, combined with specific shape design and pore structure, the problems of core misalignment and cleaning were solved, achieving stable positioning inside the castings and high-quality casting.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NANTONG JIALONG FOUNDRY CO LTD
- Filing Date
- 2025-04-02
- Publication Date
- 2026-04-10
AI Technical Summary
The core of existing valve castings is prone to displacement under the impact of high-temperature molten metal, resulting in inaccurate positioning of the internal channels of the casting. After positioning, it is difficult to remove, causing roughness on the surface of the casting and defects on the inner wall.
Soluble core holders and salt cores are used, combined with specific shape design and soluble materials. The core is removed by water-soluble or chemical means to avoid displacement and ensure the smoothness of the casting interior. Core pores and ventilation holes are set to remove gas and prevent porosity and inclusion defects.
This technology enables stable positioning of the core at high temperatures, eliminating the need for mechanical removal after casting and ensuring the casting is internally complete and defect-free, thus improving casting quality and precision.
Smart Images
Figure CN224101779U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to valve casting part technical field, concretely is a valve casting part structure convenient to core positioning. BACKGROUND
[0002] Valve casting parts usually adopt sand casting process, wherein the core plays the role of supporting and shaping, so that the molten metal can accurately fill the predetermined cavity in the casting process, and if the core positioning is not accurate, the flow channel may be deformed, the hole may be misaligned or the size deviation may occur.
[0003] The core of the commonly used valve casting part on the market is easy to shift under the impact of high-temperature molten metal, resulting in inaccurate position of the internal passage of the casting. In order to facilitate the positioning of the core, some casting parts use additional support structures or clamping devices, but these devices are often difficult to remove after casting and need to be removed by additional mechanical removal or chemical treatment. In the later cleaning process, high-pressure water flushing, vibration treatment or manual breaking are needed, which may cause the surface of the casting to be rough and even form internal wall defects.
[0004] Therefore, there is a need for a valve casting part structure convenient for core positioning to solve the above technical defects. CONTENT OF THE UTILITY MODEL
[0005] The utility model aims at providing a valve casting part structure convenient for core positioning to solve the problem of inaccurate core positioning and easy shifting or difficult removal after positioning as mentioned in the background.
[0006] To achieve the above-mentioned purpose, the utility model provides the following technical scheme: a valve casting part structure convenient for core positioning, comprising an upper sand mold and a lower sand mold, wherein the lower sand mold is arranged below the upper sand mold, the upper sand mold is provided with an upper mold cavity, the lower sand mold is provided with a lower mold cavity, a core seat is welded at the center position of the bottom of the lower mold cavity, a core is inserted into the core seat, a group of core air holes are arranged through the core along the height direction of the core, the core air holes pass through the top end of the upper sand mold, the core is a salt core, and the core seat is made of soluble material.
[0007] As a further technical scheme of the utility model, the core seat is made of paraffin material, and a groove matched with the bottom of the core is arranged in the core seat.
[0008] As a further technical scheme of the utility model, the core is a cylindrical body, and the bottom end of the core is processed into a convex wall with a curvature.
[0009] As a further technical scheme of the utility model, the connecting surface of the lower mold cavity and the upper mold cavity is a parting surface, a sprue cup is arranged on the right side of the top end of the upper sand mold, and a sprue is arranged in communication between the sprue cup and the upper mold cavity.
[0010] As a further technical scheme of the utility model, the pouring cup is gradually reduced in caliber from top to bottom.
[0011] As a further technical scheme of the utility model, a group of vent holes are formed on both sides of the top end of the upper sand mold, and a gas outlet hole is arranged beside the left vent hole.
[0012] As a further technical scheme of the utility model, pin holes are formed on both sides of the outer walls of the upper sand mold and the lower sand mold, and a closing pin is fixedly connected to the pin holes, and the upper sand mold and the lower sand mold are fixedly connected through the closing pin.
[0013] As a further technical scheme of the utility model, the upper sand mold and the lower sand mold are closed to form a hexahedron with a top opening and a complete bottom.
[0014] Compared with the prior art, the utility model has the advantages that the valve casting structure of the utility model not only prevents the core from deviating, but also removes the positioning after casting, realizes the complete inner cavity after casting, reduces casting defects, and improves casting quality.
[0015] (1) The core seat and the core are arranged, the core seat is designed in a specific shape, a groove matched with the bottom of the core is arranged in the core seat, the core seat provides fixed support for the core, the core can be stably placed in the lower mold cavity, the position of the core is prevented from deviating due to the impact of metal flow or high-temperature expansion, the salt core is selected for the core, the core can be removed by water dissolution or chemical method after casting, and the core will not be left in the final casting, the core seat is made of paraffin material, the paraffin material can be melted and discharged in the subsequent heat treatment or cleaning process, the inside of the casting is ensured to be smooth, mechanical removal is not needed, the difficulty of post-processing is reduced, the problem that the core is not accurately positioned and deviates under the impact of high-temperature metal liquid is avoided, and the problem that the casting is difficult to clean after casting is eliminated.
[0016] (2) The core gas hole, the upper sand mold and the lower sand mold are arranged, the core is used to form the inner runner of the valve casting, a group of core gas holes penetrating through the core can provide an exhaust passage during pouring, air holes or inclusion defects of the casting are prevented due to gas retention when the metal liquid is filled, the upper sand mold and the lower sand mold are closed to form a complete mold cavity, and the core is removed by dissolution after the casting is solidified, so that the inner cavity structure is complete.
[0017] (3) The upper sand mold, the lower sand mold, the pouring cup, the gas outlet hole and the vent hole are arranged, the complete casting mold cavity is formed in the upper sand mold and the lower sand mold after being closed, the vent holes arranged on both sides of the top can discharge the air in the mold cavity during the filling of the metal liquid, casting defects caused by air retention are avoided, the gas outlet hole is beside the left vent hole, the problems of shrinkage and slag inclusion are reduced, the caliber of the pouring cup is gradually reduced, the speed of the metal liquid flowing in is more stable, turbulence is reduced, and the casting quality is improved. Attached Figure Description
[0018] Figure 1 This is a front view cross-sectional structural diagram of the present invention;
[0019] Figure 2 This is a front view cross-sectional structural diagram of the lower sand mold of this utility model;
[0020] Figure 3 This is a front view cross-sectional structural diagram of the upper sand mold of this utility model;
[0021] Figure 4 This is a three-dimensional structural diagram of the core holder of this utility model.
[0022] In the diagram: 1. Upper sand mold; 2. Vent hole; 3. Air outlet; 4. Core vent; 5. Sprue cup; 6. Sprue; 7. Upper cavity; 8. Closing pin; 9. Core seat; 10. Core; 11. Lower sand mold; 12. Lower cavity; 13. Parting surface; 14. Pin hole. Detailed Implementation
[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0024] Please see Figures 1-4 The present invention provides an embodiment of a valve casting structure for easy core positioning, comprising an upper sand mold 1 and a lower sand mold 11. The lower sand mold 11 is provided below the upper sand mold 1. An upper cavity 7 is provided inside the upper sand mold 1, and a lower cavity 12 is provided inside the lower sand mold 11. A core seat 9 is welded to the bottom center of the lower cavity 12. A core 10 is inserted into the core seat 9. A set of core vent holes 4 are provided through the center of the core 10 along its height direction. The core vent holes 4 are connected to the top of the upper sand mold 1. The core 10 is a salt core. The core seat 9 is made of a soluble material. The core seat 9 is made of paraffin wax. A groove matching the bottom of the core 10 is provided inside the core seat 9. The core 10 is a cylinder. The bottom end of the core 10 is machined into a convex wall with an arc.
[0025] Specifically, such as Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, the core seat 9 is designed in a specific shape, and a groove matched with the bottom of the core 10 is arranged inside the core seat 9. The core seat 9 provides fixed support for the core 10, so that the core 10 can be stably placed inside the lower mold cavity 12, avoiding the position deviation of the core 10 caused by the impact of metal flow or high-temperature expansion. The core 10 is selected as a salt core, which can be removed by water dissolution or chemical method after the casting is completed, and will not be left inside the final casting. The core seat 9 is made of paraffin material, which can be melted and discharged in the subsequent heat treatment or cleaning process, ensuring the smoothness inside the casting and eliminating the need for mechanical removal.
[0026] The upper sand mold 1 and the lower sand mold 11 are fixedly connected by the closing pin 8 through the pin holes 14 arranged on the two sides of the outer walls of the upper sand mold 1 and the lower sand mold 11. The upper sand mold 1 and the lower sand mold 11 are fixedly connected by the closing pin 8. After the upper sand mold 1 and the lower sand mold 11 are closed, a hexahedron with an open top and a complete bottom is formed.
[0027] Specifically, as shown in Figure 1 , Figure 2 , Figure 3 and Figure 4 , the core 10 is used to form the internal flow channel of the valve casting. A group of core air holes 4 penetrating through the core 10 can provide an exhaust passage during the casting process, preventing the casting from producing pores or inclusion defects caused by gas retention when the metal liquid is filled. After the upper sand mold 1 and the lower sand mold 11 are folded, a complete mold cavity is formed, ensuring the sealing and precision during the casting process. During casting, the metal liquid enters from the sprue cup 5, flows into the upper mold cavity 7 and the lower mold cavity 12 through the runner 6, and covers the core 10 to complete the internal cavity forming. After the casting is solidified, the core 10 is removed by dissolution.
[0028] The connecting surface between the lower mold cavity 12 and the upper mold cavity 7 is the parting surface 13. The upper sand mold 1 is provided with the sprue cup 5 at the top right side. The sprue cup 5 is in communication with the upper mold cavity 7 through the runner 6. The caliber of the sprue cup 5 gradually decreases from top to bottom. A group of air holes 2 are arranged on each side of the top of the upper sand mold 1. The air outlet hole 3 is arranged beside the left air hole 2.
[0029] Specifically, as shown in Figure 1 , Figure 2 , Figure 3 and Figure 4 Figure 1 Figure 2 Figure 3 Figure 4 , after the upper sand mold 1 and the lower sand mold 11 are closed, a complete casting mold cavity is formed inside. The air holes 2 arranged on both sides of the top can remove the air inside the mold cavity during the metal liquid filling process, avoiding casting defects caused by gas retention. The air outlet hole 3 is arranged beside the left air hole 2, reducing the problems of shrinkage and slag inclusion. The sprue cup 5 is designed with a gradually decreasing caliber, so that the speed of the metal liquid flowing in is more stable.
[0030] Working principle: after the upper sand mold 1 and the lower sand mold 11 are closed, a complete casting cavity is formed inside, the core 10 is used to form the internal flow passage of the valve casting, a group of core air holes 4 penetrating through the core 10 can provide an exhaust passage during casting to prevent the casting from producing pores or inclusion defects due to gas retention when the metal liquid is filled, the upper sand mold 1 and the lower sand mold 11 are closed to form a complete cavity, ensuring the sealing and precision during casting, when casting, the metal liquid enters from the pouring cup 5, flows into the upper cavity 7 and the lower cavity 12 through the sprue 6, and completes the internal cavity forming of the core 10, after the casting is solidified, the core 10 is removed by dissolution, the core seat 9 is designed in a special shape, and a groove matched with the bottom of the core 10 is arranged inside, the core seat 9 provides fixed support for the core 10, so that the core 10 can be stably placed inside the lower cavity 12, and the position of the core 10 is prevented from being deviated due to the impact of metal flow or high-temperature expansion, the core 10 is selected from a salt core, which can be removed by water dissolution or chemical method after casting, and will not be left in the final casting, the core seat 9 is made of paraffin material, which can be melted and discharged in the subsequent heat treatment or cleaning process, so that the inside of the casting is smooth and does not need to be mechanically removed.
[0031] It is apparent for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application. Any reference signs in the claims should not be regarded as limiting the involved claims.
Claims
1. A valve casting structure for facilitating core positioning, comprising an upper sand mold (1) and a lower sand mold (11), characterized in that: The upper sand mold (1) is provided below with a lower sand mold (11), the upper sand mold (1) is provided with an upper mold cavity (7), the lower sand mold (11) is provided with a lower mold cavity (12), a core seat (9) is welded at the bottom center position of the lower mold cavity (12), a core (10) is inserted into the core seat (9), a group of core air holes (4) are penetrated through the center of the core (10) along the height direction, the core air holes (4) penetrate through the top end of the upper sand mold (1), the core (10) is a salt core, and the core seat (9) is a soluble material.
2. The valve casting structure according to claim 1, characterized by: The core seat (9) is made of paraffin material, and the core seat (9) is provided with a groove matched with the bottom of the core (10).
3. The valve casting structure of claim 1, wherein: The core (10) is a cylinder, and the bottom end of the core (10) is processed into a convex wall with an arc.
4. The valve casting structure of claim 1, wherein: The connecting surface of the lower mold cavity (12) and the upper mold cavity (7) is a parting surface (13), a sprue cup (5) is arranged at the top right side of the upper sand mold (1), and a sprue (6) is arranged in communication between the sprue cup (5) and the upper mold cavity (7).
5. The valve casting structure of claim 4, wherein: The diameter of the sprue cup (5) gradually decreases from top to bottom.
6. The valve casting structure of claim 1, wherein: A group of air vents (2) are arranged on both sides of the top end of the upper sand mold (1), and an air outlet (3) is arranged beside the left air vent (2).
7. The valve casting structure of claim 1, wherein: Pin holes (14) are arranged on the outer walls of the upper sand mold (1) and the lower sand mold (11), the pin holes (14) are fixedly connected with closing pins (8), and the upper sand mold (1) and the lower sand mold (11) are fixedly connected through the closing pins (8).
8. The valve casting structure of claim 1, wherein: The upper sand mold (1) and the lower sand mold (11) are closed into a hexahedron with an opening at the top and a complete bottom.