Mold cooling device for casting processing

Abstract

This invention discloses a mold cooling device for casting, relating to the application field of sand casting equipment. The mold includes upper and lower sand boxes and a sample mold, with a sand mold for casting filling the space between the upper and lower sand boxes. The lower sand box includes a box body, with a water storage and heat dissipation layer inside the box body, filled with cooling water. A reinforcing layer is provided on the outside of the box body, and a cooling coil is installed between the box body and the reinforcing layer, connected to a water circulation device. This invention, by setting a water storage and heat dissipation layer on the inner wall of the sand box as a heat transfer buffer, can better dissipate heat from the casting. The convective heat transfer and temperature uniformity of the water in the water storage and heat dissipation layer are better. The heat from the single high-temperature area of ​​the thick local area of ​​the irregular part is quickly dispersed into the entire interlayer by the water storage and heat dissipation layer, thereby making the overall heat load transferred to the outer cooling coil more even, significantly reducing the temperature difference between different sections of the coil, and making the heating and heat exchange more consistent.

Description

Technical Field

[0001] This invention relates to the field of sand casting equipment applications, specifically a mold cooling device for casting processing. Background Technology

[0002] Sand casting is the most traditional and widely used liquid metal forming process. Molten metal is poured into a sand mold, and after cooling, a casting is obtained. Sand is used as the molding material. First, a sand mold cavity is made that is opposite to the shape of the part. High-temperature molten metal is poured into the mold cavity. After the metal solidifies and cools, the sand mold is broken, the casting is removed, and then the finished product is cleaned and repaired.

[0003] The main equipment for sand casting includes upper and lower sand boxes and a pattern mold. The sand material is compacted in the lower sand box, and then the pattern mold is placed, with one half of the pattern mold recessed and the other half exposed. Then the upper and lower sand boxes are combined, and the sand mold is filled into the upper sand box from above. Finally, the boxes are disassembled and the pattern mold is removed. Then the boxes are closed, and metals such as cast iron, cast steel, and aluminum alloys are heated and melted into liquid and poured into the sand mold cavity. The metal cools and solidifies inside the sand mold. Finally, the sand mold is broken to obtain the casting.

[0004] Sand casting is low-cost, with readily available raw materials (sand) and simple equipment. However, the long cooling time of sand castings is a key factor affecting sand casting capacity. Conventional sand casting mainly relies on natural cooling, using the sand mold and air for natural heat dissipation. In the early stage of casting, rapid cooling methods (such as spraying or water spraying) are strictly prohibited for in-box cooling to avoid uneven internal and external temperatures of the casting and potential microcracks. In some scenarios (such as thick and large parts), forced cooling (such as cooling coils) can be installed on the outer wall of the sand box for in-box cooling. After the casting is removed from the mold, air cooling, spray cooling, water immersion cooling, etc. can be used to shorten the overall cooling time.

[0005] Regarding the use of cooling coils, they are typically added to the outer wall of the sand box, where they are evenly distributed. Cooling coils provide indirect cooling; the water does not contact the sand mold or casting, but conducts heat only through the box wall. Their core function is to remove heat from the sand box wall, thereby reducing sand temperature and shortening cooling time. Room temperature water is preferred for circulation, as it is economical and practical. In practical applications, when castings with large variations in shape are forcibly cooled by cooling coils, the heat storage in thicker areas is much greater than in thinner areas. Consequently, the sand mold and sand box at the corresponding locations continuously transfer more heat. Thinner areas generate less heat and dissipate less heat. Therefore, within the same coil, the area directly opposite the thicker part... The pipe section has a higher water temperature and a larger heat exchange load, while the heat exchange of other pipe sections is weaker. The heating and heat exchange of the entire coil are inconsistent. The original design intended for the thin-walled part to solidify first and the thick part to solidify last (for shrinkage compensation). However, with the outer wall uniformly water-cooled, the greater the temperature difference, the faster the heat dissipation. This causes the thick part to solidify prematurely, and the riser cannot compensate for shrinkage. Shrinkage cavities and porosity are very likely to occur inside. In addition, the local temperature of the coil is too high, and boiling produces bubbles, forming air blockages and disrupting the cooling continuity. Furthermore, in the high-temperature section, minerals in the water are more likely to precipitate and form scale. The pipe diameter becomes narrower and the heat exchange continues to deteriorate. Ultimately, this leads to a disordered solidification sequence in different parts of the irregularly shaped parts, affecting product quality. Summary of the Invention

[0006] Therefore, the purpose of this invention is to provide a mold cooling device for casting processing to solve the technical problems mentioned in the background.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a mold cooling device for casting processing, wherein the mold includes an upper sand box and a lower sand box, a sample mold is provided between the upper sand box and the lower sand box, a flow channel pipe is provided on the side of the sample mold, and the space between the upper sand box and the lower sand box is filled with casting sand mold. The upper sand box and the lower sand box operate on the same principle. The lower sand box includes a box body, and a water storage and heat dissipation layer is provided inside the box body. The water storage and heat dissipation layer is filled with cooling water, and a one-way exhaust valve is provided on the top of the water storage and heat dissipation layer. A reinforcing layer is provided outside the box body, and a cooling coil is provided between the box body and the reinforcing layer. One end of the cooling coil is provided with a water inlet, and the other end is provided with a water outlet. The water inlet and the water outlet are connected to a water circulation device.

[0008] By adopting the above technical solution, and by setting a water storage and heat dissipation layer on the inner wall of the sand box as a heat transfer buffer, the heat dissipation of the casting can be better. That is, the sand mold - sand box inner wall - water storage and heat dissipation layer - sand box outer wall - cooling coil circulating water. The convective heat transfer and temperature uniformity of the water in the water storage and heat dissipation layer will be better. The heat from the single high-temperature area of ​​the local thick area of ​​the irregular part will be quickly dispersed into the entire interlayer by the water storage and heat dissipation layer, reducing local overheating. As a result, the heat load transferred to the outer cooling coil is balanced as a whole, the temperature difference between different sections of the coil is significantly reduced, and the heating and heat exchange are more consistent, which improves the problem of local thick areas of irregular parts being hot on one side and cold on the other side.

[0009] The invention is further configured such that the cooling coil is composed of cooling grooves formed on the outer wall of the housing and the inner wall of the reinforcing layer, and the outer wall of the housing is provided with multiple sets of grooves at the location of the cooling grooves. Each set of grooves is rotatably connected to a blade, the shaft of the blade extends into the interior of the water storage and heat dissipation layer, and a stirring paddle is installed at the end of the shaft.

[0010] Preferably, by setting up a cooling coil to circulate room temperature cooling water, the heat of the water storage and heat dissipation layer can be removed, which can accelerate the cooling of the casting. A blade and a stirring paddle are set in the cooling tank that forms the cooling coil. The flow of cooling water drives the blade with the arc-shaped opening to rotate, which in turn drives the stirring paddle to rotate, making the temperature distribution of the distilled water in the water storage and heat dissipation layer more uniform.

[0011] The present invention is further configured such that a flow divider is provided on the side of each of the multiple sets of grooves, one end of the flow divider is connected to the cooling groove, the other end of the flow divider is connected to the groove, and the outlet end of the flow divider is tangent to the outer contour of the groove.

[0012] Preferably, by setting up multiple flow channels and cooling channels in combination, when room temperature cooling water flows, the impact of the water can act on one circle of the blade, making it rotate better.

[0013] The present invention is further configured such that multiple sets of extension sleeves are provided inside the box at the bottom edge, all of which are hollow and the internal space of the multiple sets of extension sleeves are connected to the water storage and heat dissipation layer.

[0014] Preferably, multiple sets of extension sleeves are set up. The extension sleeves are used to absorb the heat of the sand mold and generate boiling bubbles. The bubbles are used to agitate the distilled water in the water storage and heat dissipation layer, so that the temperature distribution is more uniform. In the upper sand box, the extension sleeves also need to be set at the bottom edge. However, in order to avoid interfering with the placement of the sample mold, the extension sleeves are installed in small size.

[0015] The present invention is further configured such that a water inlet is provided on the side of the box body, the water inlet is connected to the water storage and heat dissipation layer, and a drain outlet is provided at the bottom of the box body, the drain outlet is connected to the water storage and heat dissipation layer.

[0016] Preferably, a water inlet and a drain outlet are provided for adding distilled water to the water storage and heat dissipation layer and for draining and replacing water.

[0017] The present invention is further configured such that a grid plate is provided inside the box body, and the grid plate is located at the bottom edge of the box body.

[0018] Preferably, by setting a grating plate, not only can the strength of the sand box be increased, but it can also provide attachment points for the sand mold, making it more solid after molding.

[0019] The present invention is further configured such that the outer wall of the reinforcing layer is provided with multiple sets of hooks, which are evenly distributed.

[0020] Preferably, multiple sets of hooks are provided to facilitate the relocation of the sand box using auxiliary tools, such as a crane.

[0021] The present invention is further configured such that the upper sand box and the lower sand box are assembled by means of a bolt-fixed clamping assembly.

[0022] Preferably, a bolt-fixed clamping assembly is provided to fix the upper and lower sand boxes, such as upper and lower clamping plates that are bolted on.

[0023] In summary, the present invention has the following main beneficial effects:

[0024] 1. This invention, by setting a water-storage heat dissipation layer on the inner wall of the sand box as a heat transfer buffer, can better dissipate heat from the casting. That is, the sand mold - sand box inner wall - water-storage heat dissipation layer - sand box outer wall - cooling coil circulating water. The water in the water-storage heat dissipation layer has better convective heat transfer and temperature uniformity. The heat from the single high-temperature area of ​​the local thick area of ​​the irregular part will be quickly dispersed into the entire interlayer by the water-storage heat dissipation layer, reducing local overheating. As a result, the heat load transferred to the outer cooling coil is balanced as a whole, the temperature difference between different sections of the coil is significantly reduced, and the heating and heat exchange are more consistent, which improves the problem of local thick areas of irregular parts being hot on one side and cold on the other side.

[0025] 2. The water storage and heat dissipation layer and cooling coil of this invention form a double-layer water-cooling structure. The heat dissipation is a gradient-type slow cooling with a gentle cooling rate. Distilled water can be used in the water storage and heat dissipation layer for long-term use. A one-way exhaust valve is also provided to keep the water storage and heat dissipation layer at constant pressure. The water temperature is locked at a maximum of 100 degrees Celsius. Therefore, the outer cooling coil is not only heated evenly, but also has a limited heat transfer temperature, reducing the original phenomenon of local high boiling, air blockage, and scaling in the cooling coil.

[0026] 3. This invention sets small blades and agitators at local locations in the cooling coil. The power of the circulating water at room temperature in the cooling coil drives a small number of agitators to rotate, which improves the temperature uniformity of the water in the water storage and heat dissipation layer. The rotation of the agitators can increase the convection of the water in the water storage and heat dissipation layer, making the water temperature more uniform, thereby improving the heat dissipation effect of the casting.

[0027] 4. The water storage and heat dissipation layer of the present invention also has an extension sleeve inside the sand box. The space inside the extension sleeve is connected to the water storage and heat dissipation layer. The extension sleeve is located below the casting. By utilizing the heat transfer characteristics of the casting to the surroundings, the water inside the extension sleeve can also absorb heat, which improves the heat transfer efficiency. At the same time, since the extension sleeve is located at the bottom of the sand box, when the water inside it is heated and boils and generates bubbles, it will float upwards. Thus, the bubbles generated by water evaporation agitate the entire water storage and heat dissipation layer, further improving the temperature uniformity of the water inside the water storage and heat dissipation layer. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the assembly of the upper and lower sand boxes of the present invention;

[0029] Figure 2 This is a demonstration diagram of the upper sand box, lower sand box, and sample mold assembly of the present invention;

[0030] Figure 3 This is a schematic diagram of the lower sand box structure of the present invention;

[0031] Figure 4 This is a schematic diagram of the cooling groove structure on the outer wall of the housing according to the present invention;

[0032] Figure 5 For the present invention Figure 4 Enlarged view of point A in the image;

[0033] Figure 6 This is a schematic diagram of the cooling pipe structure of the present invention;

[0034] Figure 7 This is a schematic diagram of the water storage and heat dissipation layer distribution of the present invention;

[0035] Figure 8 This is a schematic diagram of the bottom structure of the lower sand box of the present invention.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1. Housing; 2. Water storage and heat dissipation layer; 3. Extension sleeve; 4. Reinforcing layer; 5. Cooling coil; 6. Water inlet; 7. Water outlet; 8. Cooling tank; 9. Groove; 10. Paddle; 11. Diversion channel; 12. Agitator; 13. Water inlet; 14. Drain outlet; 15. Grating plate; 16. Hook; 17. Template; 18. Flow channel pipe. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0039] The embodiments of the present invention will now be described.

[0040] Please see Figures 1-8A mold cooling device for casting processing is disclosed. The mold includes an upper sand box and a lower sand box. A template 17 is provided between the upper sand box and the lower sand box. The template 17 is used to form an inner cavity that matches the casting. A flow channel pipe 18 is provided on the side of the template 17. The flow channel pipe 18 is used to form a liquid metal pouring port. The upper sand box and the lower sand box are filled with casting sand molds. The lower sand box includes a box body 1. A water storage and heat dissipation layer 2 is provided inside the box body 1. The water storage and heat dissipation layer 2 is filled with cooling water, preferably distilled water, to reduce scale formation. The cooling water is not completely filled. A one-way exhaust valve is provided on the top of the water storage and heat dissipation layer 2. A reinforcing layer 4 is provided on the outside of the box body 1. A cooling coil 5 is provided between the box body 1 and the reinforcing layer 4. A water inlet 6 is provided at one end of the cooling coil 5, and a water outlet 7 is provided at the other end. The water inlet 6 and the water outlet 7 are connected to a water circulation device.

[0041] Please refer to the above embodiments for further details. Figures 4-6 The cooling coil 5 is composed of cooling grooves 8 formed on the outer wall of the housing 1 and the inner wall of the reinforcing layer 4. Multiple sets of grooves 9 are formed on the outer wall of the housing 1 at the location of the cooling grooves 8. Each set of grooves 9 is rotatably connected to a blade 10. The shaft of the blade 10 extends into the interior of the water storage and heat dissipation layer 2, and an agitator 12 is installed at the end of the shaft. By setting up the cooling coil 5 to circulate room temperature cooling water, the heat of the water storage and heat dissipation layer 2 can be removed, which can accelerate the cooling of the casting. The blades 10 and the agitator 12 are set in the cooling grooves 8 that form the cooling coil 5. The flow of cooling water drives the blades 10 with arc-shaped openings to rotate, which in turn drives the agitator 12 to rotate, making the temperature distribution of the distilled water in the water storage and heat dissipation layer 2 more uniform.

[0042] Please refer to the above embodiments for further details. Figure 5 Each of the multiple sets of grooves 9 has a diversion groove 11 on its side. One end of the diversion groove 11 is connected to the cooling groove 8, and the other end of the diversion groove 11 is connected to the groove 9. The outlet end of the diversion groove 11 is tangent to the outer contour of the groove 9. By setting multiple sets of diversion grooves 11 and cooling grooves 8 to cooperate, when room temperature cooling water flows, the impact of the water can act on the periphery of the blade 10, making it rotate better.

[0043] Please refer to the above embodiments for further details. Figure 7 Inside the box 1, multiple sets of extension sleeves 3 are set at the bottom edge. All sets of extension sleeves 3 are hollow and their internal spaces are connected to the water storage and heat dissipation layer 2. By setting multiple sets of extension sleeves 3, the extension sleeves 3 are used to absorb the heat of the sand mold and generate boiling bubbles. The bubbles are used to agitate the distilled water in the water storage and heat dissipation layer 2, making its temperature distribution more uniform. In the upper sand box, the extension sleeves 3 also need to be set at the bottom edge. However, in order to avoid interfering with the placement of the sample mold 17, the extension sleeves 3 are installed in a small size.

[0044] Please refer to the above embodiments for further details. Figure 4 The side of the box 1 is provided with a water inlet 13, which is connected to the water storage and heat dissipation layer 2. The bottom of the box 1 is provided with a drain outlet 14, which is connected to the water storage and heat dissipation layer 2. The water inlet 13 and the drain outlet 14 are used to add distilled water to the water storage and heat dissipation layer 2 and drain and replace it.

[0045] Please refer to the above embodiments for further details. Figure 3 The interior of the box 1 is provided with a grating plate 15, and the grating plate 15 is located at the bottom edge of the box 1. By setting the grating plate 15, not only can the strength of the sand box be increased, but it can also provide an attachment point for the sand mold, making it more solid after molding.

[0046] Please refer to the above embodiments for further details. Figure 3 The outer wall of the reinforced layer 4 is provided with multiple sets of hooks 16, which are evenly distributed. By setting multiple sets of hooks 16, the sand box can be moved in position by auxiliary tools, such as a crane.

[0047] Please refer to the above embodiments for further details. Figure 1 The upper and lower sand boxes are assembled by setting a bolt fixing clamping assembly, which is used to fix the upper and lower sand boxes, such as the upper and lower clamping plates installed by bolts.

[0048] In practical operation, when using the mold in this application for sand casting, the lower sand box is first placed in the designated working area, then the sand mold is filled into the lower sand box and compacted, and then the sample mold 17 is placed so that the lower half of the sample mold 17 is fitted into the sand mold and the upper half is exposed. Next, with the help of tools, such as a crane, the upper sand box and the lower sand box are combined, and it is ensured that the flow channel pipe 18 on the side of the sample mold 17 passes through the grid plate 15 of the upper sand box. The sand mold is filled into the upper sand box in the same way and compacted. After a period of standing, the sand mold solidifies, the sample mold 17 is removed from the box, and finally the upper sand box and the lower sand box are combined again. The upper sand box and the lower sand box are fixed with bolts or other fixing clamping components. Finally, molten iron is poured in through the flow channel pipe 18 to form a pouring port, and then allowed to stand and cool naturally for a period of time.

[0049] After a period of static cooling, a separate natural cooling time of 0.5-1 hour can be set. Then, forced cooling inside the box is turned on. Use hoses to connect the water inlet 6 and water outlet 7 of the upper and lower sand boxes respectively. For example, directly inject room temperature water into the water inlet 6 through a faucet or hose. The hose connected to the water outlet 7 is responsible for draining the room temperature water to the designated location.

[0050] The molten iron, at approximately 1300-1500℃, transfers heat to the sand mold. The temperature of the sand mold gradually decreases from the inside out, with the temperature near the sand box wall dropping to 150-300℃. Finally, the heat is transferred to the distilled water in the water storage and heat dissipation layer 2. The distilled water in the water storage and heat dissipation layer 2 is heated to a high temperature; the portion near the inner wall of the water storage and heat dissipation layer 2 is heated to boiling and generates bubbles. The portion of distilled water distributed within the extension sleeve 3 is also heated to boiling and generates bubbles. The rising bubbles help to even out the overall temperature of the distilled water. The bubbles are discharged through a one-way vent valve. The water storage and heat dissipation layer 2 is not completely filled with distilled water; some space is left to alleviate steam pressure. The amount of distilled water in the water storage and heat dissipation layer 2 can be... Water is replenished through the water inlet 13, while room temperature water injected through the water inlet 6 circulates within the cooling coil 5, carrying away the heat from the distilled water in the water storage and heat dissipation layer 2. The room temperature water flowing in the cooling tank 8 drives the blade 10 to rotate, which in turn drives the agitator 12 to rotate. The rotation of the agitator 12 stirs the distilled water in the water storage and heat dissipation layer 2, further making the temperature distribution of the distilled water in the water storage and heat dissipation layer 2 more uniform. The room temperature water flowing in the cooling tank 8 is also diverted through the diversion channel 11. The diversion channel 11 has a smaller diameter, and its outlet end impacts the blade 10, making the blade 10 rotate more smoothly. Forced cooling of the room temperature water in the tank can last for several hours, depending on the size of the casting.

[0051] Once the casting has cooled completely inside the mold, it is ready to be unpacked. Turn off the water tap, remove the hose, loosen the bolts securing the clamping assembly, then separate the upper and lower sand boxes, break the sand mold, and remove the casting. At this point, the casting can be further cooled externally, such as by spraying or air cooling. The upper and lower sand boxes are then quickly cleaned of any remaining sand before the next sand casting. The distilled water inside the water storage and heat dissipation layer 2 still maintains a high temperature, which can keep the next sand mold filled warm, increase the temperature of the cold sand mold, and reduce the temperature difference between the sand mold and the molten iron, allowing the casting to undergo a gradient slow cooling process.

[0052] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the invention and are not intended to limit it. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the invention, but such modifications, substitutions, and variations are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A mold cooling device for casting processing, characterized in that: The mold includes an upper sand box and a lower sand box. A sample mold (17) is provided between the upper sand box and the lower sand box. A flow channel pipe (18) is provided on the side of the sample mold (17). The upper sand box and the lower sand box are filled with casting sand molds. The lower sand box includes a box body (1). A water storage and heat dissipation layer (2) is provided inside the box body (1). Cooling water is filled inside the water storage and heat dissipation layer (2). A one-way exhaust valve is provided on the top of the water storage and heat dissipation layer (2). A reinforcing layer (4) is provided outside the box body (1). A cooling coil (5) is provided between the box body (1) and the reinforcing layer (4). A water inlet (6) is provided at one end of the cooling coil (5), and a water outlet (7) is provided at the other end. The water inlet (6) and the water outlet (7) are connected to a water circulation device.

2. The mold cooling device for casting processing according to claim 1, characterized in that: The cooling coil (5) is composed of cooling grooves (8) opened on the outer wall of the box (1) and the inner wall of the reinforcing layer (4). The outer wall of the box (1) is provided with multiple sets of grooves (9) at the position of the cooling grooves (8). Each set of grooves (9) is rotatably connected to a blade (10). The shaft of the blade (10) extends into the interior of the water storage and heat dissipation layer (2), and a stirring blade (12) is installed at the end of the shaft.

3. The mold cooling device for casting processing according to claim 2, characterized in that: Each of the multiple sets of grooves (9) has a flow divider (11) on its side. One end of the flow divider (11) is connected to the cooling tank (8), and the other end of the flow divider (11) is connected to the groove (9). The outlet end of the flow divider (11) is tangent to the outer contour of the groove (9).

4. A mold cooling device for casting processing according to claim 3, characterized in that: The interior of the box (1) is provided with multiple sets of extension sleeves (3) at the bottom edge. All sets of extension sleeves (3) are hollow and the internal space of the multiple sets of extension sleeves (3) is connected to the water storage and heat dissipation layer (2).

5. A mold cooling device for casting processing according to claim 4, characterized in that: The side of the box (1) is provided with a water inlet (13), which is connected to the water storage and heat dissipation layer (2), and the bottom of the box (1) is provided with a drain outlet (14), which is connected to the water storage and heat dissipation layer (2).

6. A mold cooling device for casting processing according to claim 1, characterized in that: The box (1) is provided with a grid plate (15) inside, and the grid plate (15) is located at the bottom edge of the box (1).

7. A mold cooling device for casting processing according to claim 1, characterized in that: The outer wall of the reinforcing layer (4) is provided with multiple sets of hooks (16), which are evenly distributed.

8. A mold cooling device for casting processing according to claim 1, characterized in that: The upper and lower sand boxes are assembled by using bolt-fixed clamping components.

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