A manufacturing process of a mold part with conformal waterways
By combining machining and metal casting, the problems of poor heat transfer effect and welding leakage in the mold's conformal water channel were solved, achieving efficient and uniform cooling effect and improving the quality and life of the mold.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TAIZHOU VOCATIONAL & TECHN COLLEGE
- Filing Date
- 2022-11-15
- Publication Date
- 2026-06-09
AI Technical Summary
The heat transfer effect of conformal water channels in existing molds is poor, the quality is low, the life is short, and the weld joints are prone to leakage, which affects the uniformity of cooling effect.
The method combines machining and metal casting. Grooves are machined on the base of the mold part and a conformal water channel model is embedded. High-temperature molten metal is poured in to form the casting part. The conformal water channel model is melted and cooled in a vacuum environment to form a complete water channel without cutting or welding. Combined with precision machining, it is ensured that the water channel is close to the mold cavity contour surface to achieve uniform cooling.
It improves the surface hardness, fatigue resistance, and corrosion resistance of the mold, enhances heat transfer, prevents leakage, ensures the rational design of the cooling water system, shortens cooling time, and improves cooling efficiency.
Smart Images
Figure CN117206845B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of mold processing technology and relates to a manufacturing process for mold parts with conformal water channels. Background Technology
[0002] A mold typically consists of multiple mold parts, such as a template, moving mold, and fixed mold. After closing, these parts form a cavity for molding the workpiece. To cool the mold, water channels are usually installed around the cavity. The shape of the mold cavity is determined by the workpiece, and the cavity's contour surface is mostly curved. However, the water channels in traditional molds are straight and on the same plane. Therefore, the distance from the center of the water channel to different parts of the cavity's contour surface is uneven, resulting in uneven cooling and affecting the quality of the injection-molded workpiece.
[0003] To address this, a mold with conformal water channels has been developed. The so-called conformal water channels refer to water channels that are distributed around the mold cavity in a trajectory consistent with the shape of the mold cavity, which can ensure that the distance between each water channel and the mold cavity contour surface is consistent, resulting in uniform cooling effect.
[0004] Existing molds with conformal water channels are all made using the following methods: For example, Chinese patent application (application number: 201510051427.9) discloses a mold with conformal water channels and its manufacturing method. The method includes: firstly, splitting the mold core into three parts at the water channel location: upper and lower mold cores and the water channel; firstly, making a water channel model and a lower mold core auxiliary forming fixture; then, using metal powder pressing technology, pressing the lower mold core model with the lower mold core auxiliary forming fixture; then placing the water channel model on the lower mold core model; then continuing to fill with metal powder and press; finally, forming a mold core model with an embedded water channel model in the forming groove; sintering and degreasing the mold core model to remove the resin-made water channel model; and then molding the upper and lower mold core models as a single piece, thus producing a mold core with conformal water channels. The conformal water channels are distributed around the cavity in a trajectory consistent with the shape of the cavity, which can uniformly cool the cavity.
[0005] The molds made using the above method form conformal water channels by direct sintering of metal forming powder. The inner walls of the conformal water channels are relatively smooth, and the roughness is uncontrollable, affecting the heat transfer effect. At the same time, the molds made by integral sintering result in a loose, porous prototype structure with internal stress, making them prone to deformation during manufacturing. The mold cavity contour surface is rough and porous and is limited by the size of the powder particles and the laser spot, making post-processing more difficult. Compared with molds made by machining mold steel, the overall mold quality and lifespan are worse.
[0006] Due to the complex shape of conformal water channels, machining of these channels within the mold steel is impossible. Therefore, to ensure heat transfer efficiency and mold quality, the conventional approach is to manufacture the entire mold in multiple modular pieces. Specifically, mold steel is cut into layers of plates, and conformal water channel segments are machined into each plate. The inner walls of these segments are then ground to increase roughness. Finally, the plates are stacked and welded together to form a complete conformal water channel. However, molds manufactured using this method are prone to leakage at the weld joints, and the overall smoothness of the conformal water channel is poor, affecting the uniformity of cooling. Summary of the Invention
[0007] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a manufacturing process for mold parts with conformal water channels. The technical problem to be solved by this invention is: how to solve the problems of poor heat transfer effect, poor quality, and short lifespan of molds manufactured by existing processes.
[0008] The objective of this invention can be achieved through the following technical solution: a manufacturing process for a mold part with conformal water channels, characterized in that the process includes the following steps:
[0009] A. Select mold steel as the base material for the part, and machine the mold cavity contour surface on the base material to form the base part of the mold part;
[0010] B1. The side of the base part away from the mold cavity contour surface is machined to form a cavity, and a groove is machined on the bottom wall of the cavity. The inner wall of the groove is roughened.
[0011] B2. Select a metal material with a melting point lower than the above-mentioned mold steel and process it into a conformal water channel model. The outer diameter of the conformal water channel model matches the inner diameter of the above-mentioned groove. Embed the conformal water channel model into the groove and fix it.
[0012] C1. Pour a liquid metal material with a melting point higher than the above-mentioned conformal water channel model into the cavity, and after cooling and solidification, form a casting part.
[0013] C2. Then, heat preservation treatment is carried out to melt the above-mentioned conformal water channel model into liquid and flow out to form conformal water channels. After cooling, the mold part with conformal water channels is completed.
[0014] A mold is generally composed of multiple mold parts that can be joined together to form a mold cavity. In this application, mold parts refer to components with cavity contour surfaces, such as the moving mold and fixed mold in an injection mold. This process differs from conventional techniques by employing a combination of machining and metal casting to manufacture the mold. The base portion of the mold with cavity contour surfaces is machined from mold steel. Compared to sintered mold parts, this process provides sufficient surface hardness, good core strength and toughness, better fatigue resistance, heat resistance, corrosion resistance, and less heat treatment deformation, ensuring the quality and lifespan of the mold. Then, a cavity is formed on the back side of the base (i.e., the side used to connect with the template), and a groove is machined on the bottom wall of the cavity. The shaped conformal water channel model is embedded into the groove and fixed. Then, casting molten metal is poured into the cavity to fill it (the molten metal cools and solidifies immediately after pouring, so it will not melt the conformal water channel model) to form the casting part. Then, heat preservation treatment is performed so that the conformal water channel model melts and flows out from the mold part, thereby forming a conformal water channel in the mold part. At this time, part of the inner wall of the conformal water channel is formed by the inner wall of the groove, and part is formed by pouring molten metal. During the processing of the groove, the roughness of its inner wall can also be machined, thereby increasing the contact area between the cooling water and the part after the conformal water channel is formed, increasing the heat transfer speed of the part, and improving the heat transfer effect. Meanwhile, the formed conformal water channels are all complete channels without cutting or welding, thus avoiding leakage. Furthermore, the conformal water channels are closer to the mold cavity contour surface and are not limited by the structure and shape of the mold parts. This ensures that the distance from the center of the cross-section of the conformal water channel to the mold cavity contour surface remains consistent, maximizing the rational design and layout of the cooling water channel system, shortening the cooling time in the thermoforming cycle, and enabling the plastic parts to be cooled evenly with higher cooling efficiency.
[0015] In the aforementioned manufacturing process of mold parts with conformal cooling channels, in step B1, a roughly uniform wall thickness is ensured between the bottom of the groove and the mold cavity contour surface. The conformal cooling channel model is then embedded into the groove and fixed tightly against its inner wall. After heat preservation and melting, the inner wall of the groove constitutes part of the conformal cooling channel. During the processing of the groove, the roughness of its inner wall can be machined to increase the contact area between the cooling water and the part, increasing the heat transfer rate and improving the heat transfer effect. Simultaneously, the uniform wall thickness ensures that the distance from the center of the conformal cooling channel section to the mold cavity contour surface remains consistent, maximizing the rational design and layout of the cooling water system, shortening the cooling time in the thermoforming cycle, and resulting in uniform cooling of the plastic part with higher cooling efficiency.
[0016] In the above-described manufacturing process of mold parts with conformal water channels, in step B1, the wall thickness between the bottom of the groove and the mold cavity contour surface is ensured to be 3-15 mm. Setting the wall thickness within this range ensures sufficient strength of the mold cavity forming surface, prevents deformation of the mold cavity contour surface, and guarantees the quality and lifespan of the mold. Simultaneously, this wall thickness spacing ensures a good cooling distance and a good cooling effect.
[0017] In the above-described manufacturing process of mold parts with conformal water channels, in step B1, the roughness of the inner wall of the groove is ensured to be greater than Ra12.5. Through the above design, after forming the conformal water channels, the contact area between the cooling water and the part can be increased to a greater extent, thereby increasing the heat transfer rate of the part.
[0018] In the aforementioned manufacturing process of mold parts with conformal water channels, in steps B1 and B2, multiple grooves are machined into the bottom wall of the cavity, and a conformal water channel model is fixed in each groove. This design allows for the creation of multiple conformal water channels, each with a diameter that can be the same or different. Different temperatures of cooling media can also be introduced into each water channel, with enhanced cooling in some areas and higher-temperature cooling media added to thin-walled sections. For injection-molded products with complex structures, a control system can be used to adjust the flow rate and temperature of the cooling media in the channels in real time, promoting the optimal solidification sequence of the plastic melt.
[0019] In the aforementioned manufacturing process of mold parts with conformal water channels, in step B2, after each conformal water channel model is fixed, both the inlet and outlet ends extend out of the cavity. This prevents blockage when molten metal is poured into the cavity later, ensuring that the liquid generated after the conformal water channel pipe model melts during the subsequent heat preservation process can flow smoothly out of the mold part, forming a complete conformal water channel within the mold part. Preferably, the extension length of the inlet and outlet ends of the conformal water channel pipe model is ≥10cm.
[0020] In the aforementioned manufacturing process of mold parts with conformal water channels, in step A, a three-dimensional modeling design of the mold part with conformal water channels is first created using 3D modeling software. Then, mold steel is selected as the base material for the part based on the three-dimensional modeling design and processed to form the base body of the part with the mold cavity contour surface. Performing three-dimensional modeling first allows for structural refinement before manufacturing, minimizing errors.
[0021] In the above-described manufacturing process of mold parts with conformal water channels, in step B2, the metal material used to form the conformal water channel model is an aluminum tube, magnesium tube, aluminum rod, or magnesium rod with a diameter of 3-10 mm. Aluminum tubes, magnesium tubes, aluminum rods, or magnesium rods are relatively easy to process and form conformal water channel models. Moreover, magnesium and aluminum have lower melting points than mold steel and casting metals, and are also easier to melt and flow out of the mold parts, thereby forming conformal water channels in the mold parts.
[0022] In the aforementioned manufacturing process of mold parts with conformal water channels, in step C1, the liquid metal material used for casting is molten ductile iron or copper alloy. Using this material results in good bonding with the mold steel, and its melting point is much higher than that of aluminum and magnesium. It will not deform during subsequent heat preservation treatment. Furthermore, the thermal conductivity of these two metals is much higher than that of the mold steel, thereby effectively improving the mold cooling efficiency while ensuring the mechanical properties of the parts.
[0023] In the aforementioned manufacturing process of mold parts with conformal water channels, in step C2, the heat preservation treatment is carried out in a vacuum environment, and the heat preservation temperature is controlled to be 100-300°C higher than the melting point of the metal material used to form the conformal water channel model. The vacuum environment allows the conformal water channel model to melt more easily and flow out of the mold part, while maintaining the heat preservation temperature 100-300°C above the melting point of the metal material ensures that the conformal water channel model can fully melt, avoids residue, and guarantees the quality of the formed conformal water channel.
[0024] In the above-described manufacturing process of mold parts with conformal water channels, step C2 involves continuous heat preservation for 20–90 minutes. This continuous heat preservation ensures the conformal water channel model is fully melted, preventing residue buildup, and also avoids thermal deformation of the mold parts themselves due to excessively long heat preservation times.
[0025] In the above-described manufacturing process of mold parts with conformal water channels, in step C2, after the mold parts are manufactured, they are further subjected to precision machining. After the conformal water channels are formed within the mold parts, the mold parts are precision machined to ensure that their dimensions and tolerances meet the technical requirements of the three-dimensional design drawings. Precision machining generally includes polishing and grinding.
[0026] Compared with existing technologies, the manufacturing process of mold parts with conformal water channels has the following advantages:
[0027] 1. The mold is manufactured by combining machining and metal casting. The base part of the mold with the mold cavity contour surface is machined from mold steel. Compared with sintered mold parts, it has sufficient surface hardness, good core strength and toughness, better fatigue resistance, heat resistance and corrosion resistance, and less heat treatment deformation performance, which ensures the quality and life of the mold.
[0028] 2. The inner wall of the formed conformal water channel is partly composed of the inner wall of the groove. During the processing of the groove, the roughness of its inner wall can be machined to make it greater than Ra12.5. This increases the contact area between the cooling water and the parts after the conformal water channel is formed, increases the heat transfer rate of the parts, and improves the heat transfer effect.
[0029] 3. The resulting conformal water channels are all complete water channels without cutting or welding, thus avoiding leakage.
[0030] 4. It can be equipped with multiple conformal water channels. The direct flow of each conformal water channel can be the same or different. Each conformal water channel can also be circulated with cooling media of different temperatures. In some places, cooling can be enhanced, and higher temperature cooling media can be added in thin-walled areas. For injection molded products with complex structures, the flow rate and temperature of the cooling media in the pipeline can be adjusted in real time through the control system to promote the formation of the optimal solidification sequence of the plastic melt.
[0031] 5. The conformal cooling channel is closer to the mold cavity contour surface and is not limited by the structure and shape of the mold parts. It can ensure that the distance from the center of the cross section of the conformal cooling channel to the mold cavity contour surface is consistent, which maximizes the rational design and layout of the cooling water channel system, shortens the cooling time in the thermoforming cycle, and makes the plastic parts cool evenly and with higher cooling efficiency. Attached Figure Description
[0032] Figure 1 A cross-sectional view of the matrix formed in step A.
[0033] Figure 2 This is a cross-sectional view of the structure after the cavity and groove are formed on the base in step B1.
[0034] Figure 3 This is a cross-sectional view of the structure after the conformal waterway model is installed and fixed inside the cavity in step B2.
[0035] Figure 4 This is a top view of the structure after the conformal waterway model is installed and fixed inside the cavity in step B2.
[0036] Figure 5 This is a cross-sectional view of the structure after the casting part is formed in step C1.
[0037] Figure 6 This is a schematic cross-sectional view of the structure after heat preservation and melting to form conformal water channels in step C2.
[0038] In the figure, 1 is the base; 11 is the mold cavity contour surface; 12 is the cavity; 13 is the groove; 2 is the casting part; 3 is the conformal water channel model; and 4 is the conformal water channel. Detailed Implementation
[0039] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings to further illustrate the technical solutions of the present invention. However, the present invention is not limited to these embodiments.
[0040] Example 1
[0041] This mold part with conformal water channels includes a base part 1 made of mold steel and a casting part 2 formed by casting metal material. It is manufactured using the following process, which includes the following steps:
[0042] A. First, a 3D modeling design of the mold part with conformal water channels is created using 3D modeling software. Mold steel is selected as the base material for the part, with a melting point between 1300 and 1400℃. Then, referring to the 3D modeling design, the base material is rough-machined to form the part base 1 with the mold cavity contour surface 11, as shown below. Figure 1 As shown.
[0043] B1. The side of the base part 1 facing away from the mold cavity contour surface 11 (i.e., the side used for connection with the template) is machined using CNC or other machining methods to form a cavity 12. This ensures that the bottom wall shape of the cavity 12 is consistent with the mold cavity contour surface 11, thereby creating a roughly uniform wall thickness between the bottom wall of the cavity 12 and the mold cavity contour surface 11. A groove 13 is machined into the bottom wall of the cavity 12, also ensuring a roughly uniform wall thickness between the bottom of the groove 13 and the mold cavity contour surface 11, specifically ensuring a wall thickness of 3mm between the bottom of the groove 13 and the mold cavity contour surface 11. Then, the inner wall of the groove 13 is machined to ensure that the roughness of the inner wall of the groove 13 is greater than Ra12.5. Figure 2 As shown. In this embodiment, the groove 13 is an arc-shaped groove 13, and the inner diameter of the groove 13 is 3mm.
[0044] B2 selects a metal material with a melting point lower than the aforementioned mold steel, specifically magnesium tubing. Magnesium tubing has a melting point of 651℃. It is processed to form a conformal water channel model 3 with a trajectory distribution consistent with the shape of the mold cavity contour surface 11. The outer diameter of the conformal water channel model 3 is 3mm, and the spacing between adjacent pipe sections is maintained at 6mm. The conformal water channel model 3 is embedded into the groove 13 and fixed tightly against the inner wall of the groove 13 (the specific fixing method can be welding), ensuring that the distance from the center of the cross-section of the conformal water channel model 3 to the mold cavity contour surface 11 is consistent. Simultaneously, both the inlet and outlet ends of the conformal water channel model 3 extend beyond the cavity 12, specifically by a length of 10cm. Figure 3 and 4 As shown.
[0045] C1. Pour a liquid metal material with a melting point higher than that of the aforementioned conformal water channel model 3 into cavity 12. Specifically, it is molten ductile iron, with a melting point of approximately 1200°C. After cooling and solidification, it forms casting part 2. Base part 1 and casting part 2 are connected as one unit, such as... Figure 5 As shown.
[0046] C2. Then, the base part 1 and the casting part 2 are kept in a vacuum environment for heat preservation treatment. The heat preservation temperature is controlled to be 100°C higher than the melting point of the metal material used to form the conformal water channel model 3, that is, the heat preservation temperature is controlled to be 751°C. The heat preservation treatment is continued for 90 minutes, so that the conformal water channel model 3 melts into liquid and flows out to form the conformal water channel 4. After cooling, the mold part with conformal water channels is completed, such as... Figure 6 As shown. Then, the mold parts are precision machined (including polishing, grinding, etc.) to ensure that their dimensions and tolerances meet the technical requirements of the 3D model design drawing, thus completing the manufacturing process.
[0047] This process differs from conventional techniques by employing a combination of machining and metal casting in mold manufacturing. The base part 1 of the mold, which has the cavity contour surface 11, is machined from mold steel. Compared to sintered mold parts, this method provides sufficient surface hardness, good core strength and toughness, better fatigue resistance, heat resistance and corrosion resistance, and less heat treatment deformation, ensuring the quality and lifespan of the mold. Furthermore, part of the inner wall of the formed conformal water channel 4 is formed by the inner wall of the groove 13, and part is formed by pouring molten metal. During the machining process of the groove 13, the roughness of its inner wall can be machined, thereby increasing the contact area between the cooling water and the parts after the conformal water channel is formed, increasing the heat transfer rate of the parts, and improving the heat transfer effect. Meanwhile, the formed conformal water channels 4 are all complete water channels without cutting or welding, thus avoiding leakage. Furthermore, the conformal water channels 4 are closer to the mold cavity contour surface 11 and are not limited by the structure and shape of the mold parts. This ensures that the distance from the center of the cross-section of the conformal water channel 4 to the mold cavity contour surface 11 remains consistent, maximizing the rational design and layout of the cooling water channel system, shortening the cooling time in the thermoforming cycle, and enabling the plastic parts to be cooled evenly with higher cooling efficiency.
[0048] Example 2
[0049] This mold part with conformal water channels includes a base part 1 made of mold steel and a casting part 2 formed by casting metal material. It is manufactured using the following process, which includes the following steps:
[0050] A. First, the mold parts are designed using 3D drawing software. Then, using mold flow analysis software and years of design experience, multiple conformal water channels 4 are set in different areas of the mold parts. The diameter of each conformal water channel 4 can be the same or different, forming a three-dimensional model design drawing with conformal water channels 4. In this embodiment, two conformal water channels 4 are designed. Mold steel is selected as the base material for the parts. The melting point of the mold steel is between 1300 and 1400℃. Referring to the three-dimensional model design drawing, the base material is rough-machined to form the part base 1 with the mold cavity contour surface 11.
[0051] B1. The side of the part base 1 facing away from the mold cavity contour surface 11 (i.e., the side used for connection with the template) is machined using CNC or other machining methods to form a cavity 12, ensuring that the bottom wall shape of the cavity 12 is consistent with the mold cavity contour surface 11, thereby forming a roughly uniform wall thickness between the bottom wall of the cavity 12 and the mold cavity contour surface 11. Two grooves 13 are machined on the bottom wall of the cavity 12, while also ensuring that the bottom of the grooves 13 forms a roughly uniform wall thickness between the bottom of the grooves 13 and the mold cavity contour surface 11, specifically ensuring that the wall thickness between the bottom of the grooves 13 and the mold cavity contour surface 11 is 9mm. Then, the inner wall of the grooves 13 is machined to ensure that the roughness of the inner wall of the grooves 13 is greater than Ra12.5. In this embodiment, the grooves 13 are arc-shaped grooves 13, and the inner diameter of the grooves 13 is 6mm.
[0052] B2 selects a metal material with a melting point lower than the aforementioned mold steel, specifically magnesium rods. Magnesium rods have a melting point of 651℃. These rods are processed to form conformal water channel models 3, whose trajectory distribution matches the shape of the mold cavity contour surface 11. The outer diameter of each conformal water channel model 3 is 6mm, and the spacing between adjacent pipe sections is maintained at 18mm. Two conformal water channel models 3 are formed. The two conformal water channel models 3 are then embedded into their corresponding grooves 13 and fixed tightly against the inner wall of the grooves 13 (the fixing method can be welding), ensuring that the distance from the center of the cross-section of the conformal water channel model 3 to the mold cavity contour surface 11 is consistent. Simultaneously, both the inlet and outlet ends of the conformal water channel models 3 extend beyond the cavity 12, with a specific extension length of 12cm.
[0053] C1. Pour a liquid metal material with a melting point higher than that of the aforementioned conformal water channel model 3 into the cavity 12. Specifically, it is a molten copper alloy liquid with a melting point of about 1000°C. After cooling and solidification, it forms the casting part 2. The base part 1 and the casting part 2 are connected as one unit.
[0054] C2. Then, the aforementioned base part 1 and casting part 2 are kept in a vacuum environment for heat preservation treatment. The heat preservation temperature is controlled to be 200°C higher than the melting point of the metal material used to form the conformal water channel model 3, that is, the heat preservation temperature is controlled to be 851°C. The heat preservation treatment is continued for 55 minutes, so that the conformal water channel model 3 melts into liquid and flows out to form the conformal water channel 4. After cooling, the mold part with conformal water channels is formed. Then, the mold part is precision machined (including polishing, grinding, etc.) to make its dimensions and tolerances meet the technical requirements of the three-dimensional model design drawing, and the manufacturing is completed.
[0055] This process differs from conventional techniques by employing a combination of machining and metal casting in mold manufacturing. The base part 1 of the mold, which has the cavity contour surface 11, is machined from mold steel. Compared to sintered mold parts, this method provides sufficient surface hardness, good core strength and toughness, better fatigue resistance, heat resistance and corrosion resistance, and less heat treatment deformation, ensuring the quality and lifespan of the mold. Furthermore, part of the inner wall of the formed conformal water channel 4 is formed by the inner wall of the groove 13, and part is formed by pouring molten metal. During the machining process of the groove 13, the roughness of its inner wall can be machined, thereby increasing the contact area between the cooling water and the parts after the conformal water channel is formed, increasing the heat transfer rate of the parts, and improving the heat transfer effect. Meanwhile, the formed conformal water channels 4 are all complete channels without cutting or welding, avoiding leakage. Furthermore, the conformal water channels 4 are closer to the mold cavity contour surface 11, not limited by the structure and shape of the mold parts. This ensures that the distance from the center of the cross-section of the conformal water channel 4 to the mold cavity contour surface 11 remains consistent, maximizing the rational design and layout of the cooling water system, shortening the cooling time in the thermoforming cycle, and resulting in uniform cooling of the plastic parts with higher cooling efficiency. Each conformal water channel 4 can also be circulated with cooling media of different temperatures. In areas where cooling is enhanced, higher-temperature cooling media can be added to thin-walled sections. For injection molded products with complex structures, the flow rate and temperature of the cooling media in the pipes can be adjusted in real time through the control system to promote the optimal solidification sequence of the plastic melt.
[0056] Example 3
[0057] This mold part with conformal water channels includes a base part 1 made of mold steel and a casting part 2 formed by casting metal material. It is manufactured using the following process, which includes the following steps:
[0058] A. First, a three-dimensional modeling design drawing of a mold part with conformal water channels is designed using 3D drawing software. Mold steel is selected as the base material of the part. The melting point of the mold steel is between 1300 and 1400℃. Then, referring to the three-dimensional modeling design drawing, the base material of the part is rough-machined to form the base body 1 of the part with the mold cavity contour surface 11.
[0059] B1. The side of the part base 1 facing away from the mold cavity contour surface 11 (i.e., the side used for connection with the template) is machined using CNC or other machining methods to form a cavity 12. This ensures that the bottom wall shape of the cavity 12 is consistent with the mold cavity contour surface 11, thereby creating a roughly uniform wall thickness between the bottom wall of the cavity 12 and the mold cavity contour surface 11. A groove 13 is machined into the bottom wall of the cavity 12, also ensuring a roughly uniform wall thickness between the bottom of the groove 13 and the mold cavity contour surface 11, specifically ensuring a wall thickness of 15mm between the bottom of the groove 13 and the mold cavity contour surface 11. Then, the inner wall of the groove 13 is machined to ensure that the roughness of the inner wall of the groove 13 is greater than Ra12.5 (e.g., ...). Figure 1 (As shown in step B1). In this embodiment, the groove 13 is an arc-shaped groove 13 with an inner diameter of 10mm.
[0060] B2 is made of a metal material with a melting point lower than that of the aforementioned mold steel, specifically aluminum tubing. The aluminum tubing has a melting point of 660℃. It is processed to form a conformal water channel model 3 with a trajectory distribution consistent with the shape of the mold cavity contour surface 11. The outer diameter of the conformal water channel model 3 is 10mm, and the spacing between adjacent pipe sections is maintained at 30mm. The conformal water channel model 3 is then embedded into the groove 13 and fixed tightly against the inner wall of the groove 13 (the specific fixing method can be welding), ensuring that the distance from the center of the cross-section of the conformal water channel model 3 to the mold cavity contour surface 11 is consistent. Simultaneously, both the inlet and outlet ends of the conformal water channel model 3 extend beyond the cavity 12, with a specific extension length of 15cm.
[0061] C1. Pour a liquid metal material with a melting point higher than that of the conformal water channel model 3 into the cavity 12. Specifically, it is molten ductile iron with a melting point of about 1200°C. After cooling and solidification, it forms the casting part 2. The base part 1 and the casting part 2 are connected as one unit.
[0062] C2. Then, the two aforementioned base parts 1 and casting parts 2 are kept in a vacuum environment for heat preservation treatment. The heat preservation temperature is controlled to be higher than the melting point of the metal material used to form the conformal water channel model 3 (300°C), that is, the heat preservation temperature is controlled to be 960°C. The heat preservation treatment is continued for 20 minutes, so that the conformal water channel model 3 melts into liquid and flows out to form the conformal water channel 4. After cooling, the mold part with the conformal water channel is formed. Then, the mold part is precision machined (including polishing, grinding, etc.) to make its dimensions and tolerances meet the technical requirements of the three-dimensional model design drawing, and the manufacturing is completed.
[0063] This process differs from conventional techniques by employing a combination of machining and metal casting in mold manufacturing. The base part 1 of the mold, which has the cavity contour surface 11, is machined from mold steel. Compared to sintered mold parts, this method provides sufficient surface hardness, good core strength and toughness, better fatigue resistance, heat resistance and corrosion resistance, and less heat treatment deformation, ensuring the quality and lifespan of the mold. Furthermore, part of the inner wall of the formed conformal water channel 4 is formed by the inner wall of the groove 13, and part is formed by pouring molten metal. During the machining process of the groove 13, the roughness of its inner wall can be machined, thereby increasing the contact area between the cooling water and the parts after the conformal water channel is formed, increasing the heat transfer rate of the parts, and improving the heat transfer effect. Meanwhile, the formed conformal water channels 4 are all complete water channels without cutting or welding, thus avoiding leakage. Furthermore, the conformal water channels 4 are closer to the mold cavity contour surface 11 and are not limited by the structure and shape of the mold parts. This ensures that the distance from the center of the cross-section of the conformal water channel 4 to the mold cavity contour surface 11 remains consistent, maximizing the rational design and layout of the cooling water channel system, shortening the cooling time in the thermoforming cycle, and enabling the plastic parts to be cooled evenly with higher cooling efficiency.
[0064] Example 4
[0065] This mold part with conformal water channels includes a base part 1 made of mold steel and a casting part 2 formed by casting metal material. It is manufactured using the following process, which includes the following steps:
[0066] A. First, a three-dimensional modeling design drawing of a mold part with conformal water channels is designed using 3D drawing software. Mold steel is selected as the base material of the part. The melting point of the mold steel is between 1300 and 1400℃. Then, referring to the three-dimensional modeling design drawing, the base material of the part is rough-machined to form the base body 1 of the part with the mold cavity contour surface 11.
[0067] B1. The side of the part base 1 facing away from the mold cavity contour surface 11 (i.e., the side used for connection with the template) is machined using CNC or other machining methods to form a cavity 12, ensuring that the bottom wall shape of the cavity 12 is consistent with the mold cavity contour surface 11, thereby forming a roughly uniform wall thickness between the bottom wall of the cavity 12 and the mold cavity contour surface 11. A groove 13 is machined on the bottom wall of the cavity 12, also ensuring that a roughly uniform wall thickness is formed between the bottom of the groove 13 and the mold cavity contour surface 11, specifically ensuring that the wall thickness between the bottom of the groove 13 and the mold cavity contour surface 11 is 8mm. Then, the inner wall of the groove 13 is machined to ensure that the roughness of the inner wall of the groove 13 is greater than Ra12.5. In this embodiment, the groove 13 is an arc-shaped groove 13 with an inner diameter of 5.5mm.
[0068] B2. Select a metal material with a melting point lower than the aforementioned mold steel, specifically aluminum rods. The melting point of aluminum rods is 660℃. Process the aluminum rods to form a conformal water channel model 3 with a trajectory distribution consistent with the shape of the mold cavity contour surface 11. The outer diameter of the conformal water channel model 3 is 5.5mm, and the spacing between adjacent pipe sections is maintained at 15mm. After embedding the conformal water channel model 3 into the groove 13, fix it tightly against the inner wall of the groove 13 (the specific fixing method can be welding), ensuring that the distance from the center of the cross-section of the conformal water channel model 3 to the mold cavity contour surface 11 is consistent. At the same time, ensure that both the inlet and outlet ends of the conformal water channel model 3 extend outside the cavity 12, specifically with an extension length of 13cm.
[0069] C1. Pour a liquid metal material with a melting point higher than that of the aforementioned conformal water channel model 3 into the cavity 12. Specifically, it is a molten copper alloy liquid with a melting point of about 1000°C. After cooling and solidification, it forms the casting part 2. The base part 1 and the casting part 2 are connected as one unit.
[0070] C2. Then, the two aforementioned base parts 1 and casting parts 2 are kept in a vacuum environment for heat preservation treatment. The heat preservation temperature is controlled to be higher than the melting point of the metal material used to form the conformal water channel model 3 by 150°C, that is, the heat preservation temperature is controlled to be 810°C. The heat preservation treatment is continued for 65 minutes, so that the conformal water channel model 3 melts into liquid and flows out to form the conformal water channel 4. After cooling, the mold part with conformal water channels is completed. Then, the mold part is precision machined (including polishing, grinding, etc.) to make its dimensions and tolerances meet the technical requirements of the three-dimensional model design drawing, and the manufacturing is completed.
[0071] This process differs from conventional techniques by employing a combination of machining and metal casting in mold manufacturing. The base part 1 of the mold, which has the cavity contour surface 11, is machined from mold steel. Compared to sintered mold parts, this method provides sufficient surface hardness, good core strength and toughness, better fatigue resistance, heat resistance and corrosion resistance, and less heat treatment deformation, ensuring the quality and lifespan of the mold. Furthermore, part of the inner wall of the formed conformal water channel 4 is formed by the inner wall of the groove 13, and part is formed by pouring molten metal. During the machining process of the groove 13, the roughness of its inner wall can be machined, thereby increasing the contact area between the cooling water and the parts after the conformal water channel is formed, increasing the heat transfer rate of the parts, and improving the heat transfer effect. Meanwhile, the formed conformal water channels 4 are all complete water channels without cutting or welding, thus avoiding leakage. Furthermore, the conformal water channels 4 are closer to the mold cavity contour surface 11 and are not limited by the structure and shape of the mold parts. This ensures that the distance from the center of the cross-section of the conformal water channel 4 to the mold cavity contour surface 11 remains consistent, maximizing the rational design and layout of the cooling water channel system, shortening the cooling time in the thermoforming cycle, and enabling the plastic parts to be cooled evenly with higher cooling efficiency.
[0072] Example 5
[0073] This mold part with conformal water channels includes a base part 1 made of mold steel and a casting part 2 formed by casting metal material. It is manufactured using the following process, which includes the following steps:
[0074] A. First, the mold parts are designed using 3D drawing software. Then, using mold flow analysis software and years of design experience, multiple conformal water channels 4 are set in different areas of the mold parts. The diameter of each conformal water channel 4 can be the same or different, forming a three-dimensional model design drawing with conformal water channels 4. In this embodiment, three conformal water channels 4 are designed. Mold steel is selected as the base material for the parts. The melting point of the mold steel is between 1300 and 1400℃. Referring to the three-dimensional model design drawing, the base material is rough-machined to form the part base 1 with the mold cavity contour surface 11.
[0075] B1. The side of the part base 1 facing away from the mold cavity contour surface 11 (i.e., the side used for connection with the template) is machined using CNC or other machining methods to form a cavity 12, ensuring that the bottom wall shape of the cavity 12 is consistent with the mold cavity contour surface 11, thereby forming a roughly uniform wall thickness between the bottom wall of the cavity 12 and the mold cavity contour surface 11. Two grooves 13 are machined on the bottom wall of the cavity 12, also ensuring that a roughly uniform wall thickness is formed between the bottom of the grooves 13 and the mold cavity contour surface 11, specifically ensuring that the wall thickness between the bottom of the grooves 13 and the mold cavity contour surface 11 is 11mm. Then, the inner wall of the grooves 13 is machined to ensure that the roughness of the inner wall of the grooves 13 is greater than Ra12.5. In this embodiment, the grooves 13 are arc-shaped grooves 13, and the inner diameters of the three grooves 13 are 7mm, 8mm, and 9mm, respectively.
[0076] B2. Select a metal material with a melting point lower than the aforementioned mold steel, specifically aluminum rods. The melting point of aluminum rods is 660℃. Process the aluminum rods to form conformal water channel models 3 with a trajectory distribution consistent with the shape of the mold cavity contour surface 11. In the formed conformal water channel models 3, the spacing between adjacent pipe sections is maintained at 15mm. A total of three conformal water channel models 3 are formed, with outer diameters of 7mm, 8mm, and 9mm respectively. Embed the three conformal water channel models 3 into their corresponding grooves 13 and fix them tightly against the inner wall of the grooves 13 (the specific fixing method can be welding), ensuring that the distance from the center of the cross-section of the conformal water channel model 3 to the mold cavity contour surface 11 is consistent. Simultaneously, ensure that both the inlet and outlet ends of the conformal water channel models 3 extend beyond the cavity 12, with a specific extension length of 11cm.
[0077] C1. Pour a liquid metal material with a melting point higher than that of the aforementioned conformal water channel model 3 into the cavity 12. Specifically, it is a molten copper alloy liquid with a melting point of about 1000°C. After cooling and solidification, it forms the casting part 2. The base part 1 and the casting part 2 are connected as one unit.
[0078] C2. Then, the two aforementioned base parts 1 and casting parts 2 are kept in a vacuum environment for heat preservation treatment. The heat preservation temperature is controlled to be higher than the melting point of the metal material used to form the conformal water channel model 3 (220°C), that is, the heat preservation temperature is controlled to be 880°C. The heat preservation treatment is continued for 45 minutes, so that the conformal water channel model 3 melts into liquid and flows out to form the conformal water channel 4. After cooling, the mold part with conformal water channels is formed. Then, the mold part is precision machined (including polishing, grinding, etc.) to make its dimensions and tolerances meet the technical requirements of the three-dimensional model design drawing, and the manufacturing is completed.
[0079] This process differs from conventional techniques by employing a combination of machining and metal casting in mold manufacturing. The base part 1 of the mold, which has the cavity contour surface 11, is machined from mold steel. Compared to sintered mold parts, this method provides sufficient surface hardness, good core strength and toughness, better fatigue resistance, heat resistance and corrosion resistance, and less heat treatment deformation, ensuring the quality and lifespan of the mold. Furthermore, part of the inner wall of the formed conformal water channel 4 is formed by the inner wall of the groove 13, and part is formed by pouring molten metal. During the machining process of the groove 13, the roughness of its inner wall can be machined, thereby increasing the contact area between the cooling water and the parts after the conformal water channel is formed, increasing the heat transfer rate of the parts, and improving the heat transfer effect. Meanwhile, the formed conformal water channels 4 are all complete channels without cutting or welding, avoiding leakage. Furthermore, the conformal water channels 4 are closer to the mold cavity contour surface 11, not limited by the structure and shape of the mold parts. This ensures that the distance from the center of the cross-section of the conformal water channel 4 to the mold cavity contour surface 11 remains consistent, maximizing the rational design and layout of the cooling water system, shortening the cooling time in the thermoforming cycle, and resulting in uniform cooling of the plastic parts with higher cooling efficiency. Each conformal water channel 4 can also be circulated with cooling media of different temperatures. In areas where cooling is enhanced, higher-temperature cooling media can be added to thin-walled sections. For injection molded products with complex structures, the flow rate and temperature of the cooling media in the pipes can be adjusted in real time through the control system to promote the optimal solidification sequence of the plastic melt.
[0080] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.
[0081] Although this document frequently uses terms such as base part 1, mold cavity contour surface 11, cavity 12, groove 13, casting part 2, conformal water channel model 3, and conformal water channel 4, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of the invention; interpreting them as any additional limitation would contradict the spirit of the invention.
Claims
1. A manufacturing process for a mold part with conformal water channels, characterized in that, The process includes the following steps: A. Select mold steel as the base material for the part, and process the mold cavity contour surface (11) on the base material to form the base part (1) of the mold part. B1. The side of the base part (1) away from the mold cavity contour surface (11) is processed to form a cavity (12). A groove (13) is machined on the bottom wall of the cavity (12) to ensure that the bottom of the groove (13) and the mold cavity contour surface (11) form a roughly uniform wall thickness. The inner wall of the groove (13) is roughened to ensure that the roughness of the inner wall of the groove (13) is greater than Ra12.
5. B2. Select a metal material with a melting point lower than the above-mentioned mold steel and process it into a conformal water channel model (3). The outer diameter of the conformal water channel model (3) matches the inner diameter of the above-mentioned groove (13). Embed the conformal water channel model (3) into the groove (13) and fix it. After the conformal water channel model (3) is embedded into the groove (13), it is fixed tightly against the inner wall of the groove (13). C1. Pour a liquid metal material with a melting point higher than that of the conformal water channel model (3) into the cavity (12), and after cooling and solidification, form the casting part (2). C2. Then, heat preservation treatment is carried out so that the above-mentioned conformal water channel model (3) melts into liquid and flows out to form conformal water channel (4). After cooling, the mold part with conformal water channel (4) is completed.
2. The manufacturing process of the mold part with conformal water channels according to claim 1, characterized in that, In step B1, the wall thickness between the bottom of the groove (13) and the mold cavity contour surface (11) is guaranteed to be 3 to 15 mm.
3. The manufacturing process of the mold part with conformal water channels according to claim 1 or 2, characterized in that, In steps B1 and B2, multiple grooves (13) are formed on the bottom wall of the cavity (12), and a conformal waterway model (3) is fixed in each groove (13).
4. The manufacturing process of the mold part with conformal water channels according to claim 1 or 2, characterized in that, In step B2, after each conformal waterway model (3) is fixed, both the inlet and outlet ends of the waterway extend out of the cavity (12).
5. The manufacturing process of the mold part with conformal water channels according to claim 1 or 2, characterized in that, In step B2, the metal material used to process the conformal waterway model (3) is an aluminum tube, a magnesium tube, an aluminum rod, or a magnesium rod with a diameter of 3-10 mm.
6. The manufacturing process of the mold part with conformal water channels according to claim 1 or 2, characterized in that, In step C2, the heat preservation process is carried out in a vacuum environment, and the heat preservation temperature is controlled to be 100-300°C higher than the melting point of the metal material used to process and form the conformal water channel model (3).
7. The manufacturing process of the mold part with conformal water channels according to claim 6, characterized in that, In step C2, the heat preservation treatment is continued for 20 to 90 minutes.
8. The manufacturing process of the mold part with conformal water channels according to claim 1 or 2, characterized in that, In step C1, the liquid metal material used for casting is molten ductile iron or copper alloy liquid.