A precision thin-walled pipe extrusion die

Abstract

The utility model belongs to extrusion mould technical field discloses a kind of precision thin-walled pipe extrusion mould, it includes compression mould, mouth mould and setting mould fixedly connected in proper order along processing forming direction;Compression mould is internally provided with cavity;It further includes extrusion passage, and extrusion passage is through mouth mould and setting mould and is communicated with cavity;It further includes core mould and fixed base, fixed base is fixed in cavity inside;Core mould one end is connected with fixed base, and other end is inserted into extrusion passage and is suspended;Extrusion passage quantity is two or more, and core mould quantity corresponds with extrusion passage quantity.The device of the utility model can produce multiple thin-walled pipes at a time, and the output is multiplied in unit time, which greatly improves the production efficiency.In addition, core mould and fixed base are preassembled and do not need to be on-site debug eccentricity, which can ensure the uniformity of the wall thickness of each pipeline during multi-channel extrusion.The core mould and fixed base are fixedly connected as a whole, which reduces the on-site installation alignment time, shortens the assembly time, and greatly improves the practicability of the device.

Description

Technical Field

[0001] This utility model relates to the field of extrusion die technology, and in particular to a precision thin-walled tube extrusion die. Background Technology

[0002] Precision extruded thin-walled tubes are an important industrial material widely used in automobile manufacturing, aerospace and medical devices and other fields. Their core advantages are high wall thickness uniformity and strong dimensional stability, which can meet the requirements of lightweight and high strength under complex working conditions.

[0003] The traditional production process of precision extruded thin-walled tubes mainly utilizes a single-channel extrusion die, where the material undergoes melting, molding, and cooling to form the tube. However, with increasing demands for production efficiency and cost control in the industrial sector, existing production methods have gradually revealed significant shortcomings in terms of capacity, flexibility, and practicality. On the one hand, most thin-walled extrusion dies on the market adopt a single-channel design, forming only one thin-walled tube per extrusion process. While this design is simple and direct, its production efficiency is relatively low, failing to meet the demands of large-scale and efficient production. On the other hand, different extrusion dies are often required to produce different tube materials, and each switch necessitates repeated manual adjustments to the eccentricity, which is not only time-consuming and labor-intensive but also increases production costs and downtime.

[0004] Therefore, it is necessary in this field to improve the precision thin-walled tube extrusion die to overcome the shortcomings of the existing technology. Utility Model Content

[0005] The purpose of this utility model is to provide a precision thin-walled tube extrusion die, which has a simple structure, high production efficiency, high assembly efficiency, and strong practicality.

[0006] To achieve the above objectives, this utility model provides a precision thin-walled tube extrusion die, comprising a compression die, a die head, and a shaping die connected sequentially along the forming direction; the compression die has a cavity inside; it also includes an extrusion channel that passes through the die head and the shaping die and communicates with the cavity; it further includes a core die and a fixing seat, the fixing seat being fixed inside the cavity; one end of the core die is connected to the fixing seat, and the other end extends into the extrusion channel and is suspended; the number of extrusion channels is two or more, and the number of core dies corresponds to the number of extrusion channels.

[0007] Furthermore, a guide mold is fixedly connected to the end face of the die that mates with the compression mold. The guide mold has a flared guide opening in the middle that communicates with the extrusion channel. The larger end of the flared guide opening faces the cavity, and the smaller end has the channel entrance of the extrusion channel. A flow divider is also fixedly connected inside the flared guide opening to separate the extrusion channel entrance.

[0008] Furthermore, the core mold includes a first guide portion, a second guide portion, a fixing portion, and an extrusion molding portion; the first guide portion, the second guide portion, and the fixing portion are all disposed within the cavity, and the extrusion molding portion is located within the extrusion channel and suspended; the first guide portion and the second guide portion are respectively located at both ends of the fixing portion, the first guide portion is located at the end away from the die, and the second guide portion is located between the fixing portion and the extrusion molding portion; the surfaces of the first guide portion and the second guide portion are both conical surfaces, used for guiding the material to flow along the processing and molding direction.

[0009] Furthermore, the fixing seat includes a sleeve and a fixing ring. The fixing ring is disposed outside the sleeve and is fixedly connected to the inside of the cavity; the fixing part is embedded inside the sleeve and is fixedly connected to the sleeve.

[0010] Furthermore, the cavity is a trumpet-shaped cavity whose inner cavity gradually decreases in size along the processing and forming direction, and its smaller opening end mates with the die.

[0011] Furthermore, cooling channels are provided on the molding die for cooling and shaping the product.

[0012] Furthermore, it also includes a barrel, which is fixedly connected to the compression mold via a flange.

[0013] The beneficial effects of this invention are as follows: By setting two or more extrusion channels and equipping them with corresponding mandrels, the device can produce multiple thin-walled tubes at once, doubling the output per unit time and greatly improving production efficiency. Furthermore, the pre-assembly of the mandrel and the fixed base eliminates the need for on-site adjustment of eccentricity, ensuring uniformity of pipe wall thickness during multi-channel extrusion. The fixed connection between the mandrel and the fixed base reduces on-site installation and alignment time, shortens assembly time, and greatly improves the practicality of the device. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the utility model will be further described below in conjunction with the accompanying drawings and embodiments. The drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0016] Figure 2 This is a schematic diagram of the main structure of this utility model.

[0017] Figure 3 It is along Figure 2 A structural schematic diagram shown in cross-section of plane AA.

[0018] Figure 4This is a schematic diagram of a structure in which the die, shaping die, and guide die are assembled.

[0019] Figure 5 yes Figure 4 A schematic diagram of a front view structure.

[0020] Figure 6 yes Figure 4 A schematic diagram of a side view structure.

[0021] Figure 7 It is along Figure 6 A structural schematic diagram of a cross-section of the BB plane.

[0022] Figure 8 This is a schematic diagram of the structure of a compression mold in this utility model.

[0023] Figure 9 yes Figure 8 A schematic diagram of a front view structure.

[0024] Figure 10 It is along Figure 9 A schematic diagram of a structure viewed in cross-section of the C-plane.

[0025] Figure 11 This is a schematic diagram of a structure in which the core mold and the fixed base of this utility model are matched.

[0026] Figure 12 yes Figure 11 A schematic diagram of a front view structure.

[0027] Figure 13 yes Figure 11 A schematic diagram of a side view structure.

[0028] Figure 14 It is along Figure 13 A structural schematic diagram of a cross-section of the DD plane.

[0029] Figure 15 This is a schematic diagram of the structure of the fixing base of this utility model.

[0030] Figure 16 yes Figure 15 A schematic diagram of a side view structure.

[0031] Figure 17 It is along Figure 16 A structural schematic diagram with a cross-sectional view of the EE plane.

[0032] Figure 18 This is a schematic diagram of the core mold of this utility model.

[0033] In the diagram: 1. Compression mold; 2. Die; 3. Shaping mold; 4. Cavity; 5. Extrusion channel; 6. Core mold; 7. Fixing base; 8. Guide mold; 9. Trumpet-shaped guide opening; 10. Channel inlet; 11. Diverter; 12. Cooling channel; 13. Barrel; 14. Flange; 15. Limiting protrusion; 16. Limiting groove; 17. Vent hole; 18. Connecting rod;

[0034] 601. First guide section; 602. Second guide section; 603. Fixing section; 604. Extrusion molding section;

[0035] 701. Sleeve; 702. Retaining ring. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0037] like Figures 1 to 18 As shown, a precision thin-walled tube extrusion die includes a compression die 1, a die 2, and a shaping die 3, which are fixedly connected in sequence along the processing direction; the compression die 1 has a cavity 4 inside; it also includes an extrusion channel 5, which passes through the die 2 and the shaping die 3 and communicates with the cavity 4; it also includes a core die 6 and a fixing seat 7, which is fixed inside the cavity 4; one end of the core die 6 is connected to the fixing seat 7, and the other end extends into the extrusion channel 5 and is suspended; the number of extrusion channels 5 is two or more, and the number of core dies 6 corresponds to the number of extrusion channels 5.

[0038] The device of this invention mainly serves as a mold for processing and forming precision tubes. The specific material needs to be selected according to the actual situation, such as polypropylene, polyethylene, polyvinyl chloride, and polytetrafluoroethylene, etc. During processing, the material sequentially passes through compression mold 1, die 2, and shaping mold 3. The functions of compression mold 1, die 2, and shaping mold 3 are the same as those commonly found in existing technologies. The specific material conditions at each stage are as follows:

[0039] In the compression mold 1 stage, the material enters the cavity 4 of the compression mold 1 from the outside, and is fully melted under the action of the heating device. The compression action eliminates air bubbles and increases the density to a formable state.

[0040] In the die 2 stage, the molten material enters the die 2 and remains in a flowing state in the extrusion channel 5 to prepare for shaping.

[0041] In the shaping mold 3 stage, the material enters the shaping mold 3 from the extrusion channel 5. Under the combined action of the inner wall of the extrusion channel 5 and the core mold 6, it forms a thin-walled tube, which is completely solidified to the required size of the product and output from the end of the extrusion channel 5.

[0042] In practical use, compression mold 1 and die 2 also need to be equipped with corresponding heating devices, such as segmented electric heating coils, hot oil circulation heating systems or electromagnetic induction heating devices commonly used in the prior art. Their principles are relatively common, such as the heating principle of compression mold 1 and die 2 in the patent with publication number CN223211877U, which will not be elaborated here.

[0043] like Figure 1 , Figure 3 , Figure 4 and Figure 7 As shown, in this invention, a cooling channel 12 is formed inside the forming mold 3, and the cooling channel 12 is distributed in a grid or spiral pattern around the outer periphery of the extrusion channel 5, forming a comprehensive surrounding cooling of the extrusion pipe. The two ends of the cooling channel 12 are connected to external water sources such as cooling towers, circulating water systems, or refrigeration units through interfaces, forming a closed loop. Low-temperature cooling water enters the cooling channel 12 from the inlet end and flows within it. The extrusion pipe transfers heat to the cooling water through the inner wall of the forming mold 3. The high-temperature water, after absorbing heat, flows out from the outlet end of the cooling channel 12 and returns to the external water source for cooling, achieving recycling. In actual design, it should be ensured that the cooling channel 12 evenly covers the outer periphery of the pipe to avoid localized overheating or insufficient cooling, thereby preventing the pipe from deforming due to uneven contraction.

[0044] During processing, a cooling water tank is installed behind the shaping mold 3. The extrusion pipe from the end of the extrusion channel 5 enters the cooling water tank for cooling, ensuring the product is thoroughly shaped. Multiple sets of guide rollers are also installed in the cooling water tank to ensure the straight movement of the extrusion pipe and avoid uneven cooling caused by bending and contact with the tank wall.

[0045] This invention's device, by setting up two or more extrusion channels 5 and equipping them with corresponding mandrels 6, can produce multiple thin-walled tubes at once, doubling the output per unit time and greatly improving production efficiency. It is particularly suitable for large-scale industrial production of medical catheters and automotive wiring harnesses. The mandrel 6 extends suspended into the channel, forming an annular gap with the channel's inner wall, directly determining the wall thickness of the thin-walled tube. Simultaneously, since the mandrel 6 is pre-assembled with the fixed base 7 and no on-site adjustment of eccentricity is required, the uniformity of the tube wall thickness during multi-channel extrusion is ensured. Furthermore, the mandrel 6 and the fixed base 7 are fixedly connected as one unit, reducing on-site installation and alignment time when switching between different extrusion dies, shortening assembly time, and greatly improving the device's practicality.

[0046] The device of this invention needs to be connected to extrusion equipment during use, specifically to the barrel 13 of the extruder. During use, the compression die 1 is fixedly connected to the barrel 13 via a flange 14. In this invention, a limiting protrusion ring 15 is provided on the outer surface of the end of the compression die 1 that mates with the barrel 13, and the limiting protrusion ring 15 is integrally formed with the compression die 1. A limiting groove 16 is also provided inside the barrel 13, and the limiting protrusion ring 15 is embedded in the limiting groove 16. The flange 14 is sleeved on the outer periphery of the die 2 and is bolted to the end face of the barrel 13; it is in close contact with and blocks the end face of the limiting protrusion ring 15, thereby preventing the entire compression die 1 from sliding out of the barrel 13 and preventing the compression die 1 from rotating. On the barrel 13, there are two or more evenly distributed vent holes 17 on the wall of the barrel 13 located at the limiting groove 16. The vent holes 17 provide a gas escape channel to prevent gas from being trapped in the material and avoid defects such as bubbles and holes during subsequent molding.

[0047] In practical use, two or more extrusion channels 5 can be designed with different dimensions or the same size. However, for ease of processing, this invention preferably uses channels of the same size, which greatly improves processing convenience and allows for the simultaneous production of multiple extrusion channels within a single processing cycle, effectively improving production efficiency and reducing production costs.

[0048] like Figure 3 , Figure 7 , Figure 11 , Figure 12 , Figure 14 and Figure 18 As shown, in one embodiment of this utility model, there are two extrusion channels 5, which are identical in shape and size, and each extrusion channel 5 is fitted with a corresponding mandrel 6. Having two extrusion channels 5 can improve efficiency and facilitate operation.

[0049] like Figures 4 to 17 As shown, in this embodiment, a guide mold 8 is fixedly connected to the end face of the die 2 that mates with the compression mold 1. The guide mold 8 has a flared guide opening 9 in the middle that communicates with the extrusion channel 5. The larger end of the flared guide opening 9 faces the cavity 4, and the smaller end has the channel inlet 10 of the extrusion channel 5. A flow divider 11 is also fixedly connected inside the flared guide opening 9 to separate the inlet of the extrusion channel 5. In this embodiment, the flow divider 11 is a conical block structure, positioned between the two extrusion channels 5, with its tip facing the compression mold 1. Because the flow divider 11 is a conical block structure, its inclined surface can guide the material. Cooperating with the flared guide opening 9 of the guide mold 8, it guides the material to the channel inlet 10, and then from the channel inlet 10 into the extrusion channel 5.

[0050] In this embodiment, when the extrusion equipment starts working, the material first enters the end face of the die 2 that mates with the compression die 1. Since a guide die 8 is provided on the end face, and a funnel-shaped guide opening 9 communicating with the extrusion channel 5 is provided in the middle of the guide die 8, with the larger end of the funnel-shaped guide opening 9 facing the cavity 4 and the smaller end having the channel inlet 10 of the extrusion channel 5, the material first enters the funnel-shaped guide opening 9. Because a conical block-shaped diverter 11 is provided inside the funnel-shaped guide opening 9, the material, after entering the funnel-shaped guide opening 9, is guided by the inclined surface of the conical block-shaped diverter 11. Simultaneously, combined with the shape characteristics of the funnel-shaped guide opening 9, the material is accurately guided to the channel inlets 10 of the two extrusion channels 5, and then enters the extrusion channel 5 from the channel inlets 10. Within the extrusion channel 5, it is further processed, and each extrusion channel 5 is correspondingly fitted with a core die 6 to complete the corresponding extrusion molding operation.

[0051] In this embodiment, the cooperation between the trumpet-shaped guide opening 9 of the guide die 8 and the conical block-shaped diverter 11 accurately guides the material to the entrance of the extrusion channel 5. The trumpet-shaped guide opening 9 provides a large entry space for the material and gradually narrows to guide the material flow towards the channel inlet 10. The inclined surface of the conical block-shaped diverter 11 further diverts and guides the material, ensuring that the material can enter its respective extrusion channel 5 evenly and accurately, avoiding confusion or blockage when the material enters the channel. By setting the guide die 8 on the end face of the die 2, the stability and continuity of the extrusion process are ensured, and product quality is improved.

[0052] like Figure 11 , Figure 12 , Figure 14 and Figure 18As shown, in this embodiment, the core mold 6 is integrally formed and includes a first guide portion 601, a second guide portion 602, a fixing portion 603, and an extrusion molding portion 604. The first guide portion 601, the second guide portion 602, and the fixing portion 603 are all disposed within the cavity 4, and the extrusion molding portion 604 is located within the extrusion channel 5 and suspended. The first guide portion 601 and the second guide portion 602 are respectively located at both ends of the fixing portion 603, with the first guide portion 601 located at the end furthest from the die 2, and the second guide portion 602 located between the fixing portion 603 and the extrusion molding portion 604. The surfaces of the first guide portion 601 and the second guide portion 602 are both conical surfaces, used for guiding the material flow along the processing and molding direction. The fixing seat 7 includes a sleeve 701 and a fixing ring 702. The fixing ring 702 is disposed outside the sleeve 701 and is fixedly connected to the inside of the cavity 4. The fixing portion 603 is embedded inside the sleeve 701 and fixedly connected to the sleeve 701. The fixing ring 702 and the sleeve 701 are fixedly connected by connecting rods 18, which are evenly distributed to ensure material flow space. In actual design, the sleeve 701, fixing ring 702 and connecting rods 18 can be processed separately and then welded, or they can be integrally formed. However, integral forming requires higher process requirements. This utility model prefers to process them separately and then weld them.

[0053] In this embodiment, during assembly, the retaining ring 702 is embedded into the limiting groove 16 and secured by the limiting protrusion 15. That is, the retaining seat 702 is pressed down by the compression mold 1, the compression mold 1 is pressed down by the flange 14, and the flange 14 is securely connected to the barrel.

[0054] During the assembly process, the fixing base 7 is first fitted with the core mold 6, and then the fixing ring 702 of the fixing base 7 is embedded into the limiting groove 16. During equipment maintenance, it is also convenient to remove the core mold 6 from the fixing base 7 for inspection, cleaning or replacement, which reduces the difficulty and cost of maintenance and improves the overall maintainability of the equipment.

[0055] The maximum cross-sectional diameter of the second guide portion 602, the fixing portion 603, and the extrusion molding portion 604 of the core mold 6 is smaller than the inner diameter of the sleeve 701, while the maximum cross-sectional diameter of the first guide portion 601 is larger than the inner diameter of the sleeve 701. During installation, the extrusion molding portion 604 and the second guide portion 602 of the core mold 6 pass through one end of the sleeve 701 and exit from the other end. Then, the extrusion channels 5 at the corresponding positions of the die 2 and the shaping die 3 are engaged with the extrusion molding portion 604. At this time, the first guide portion 601, the second guide portion 602, and the fixing portion 603 are all located within the cavity 4, with the fixing portion 603 located within the sleeve 701 of the fixing seat 7, and the extrusion molding portion 604 located within the extrusion channel 5 and suspended in the air, preparing for subsequent material extrusion molding.

[0056] During the material flow process, the material enters the cavity 4 and flows towards the extrusion channel 5, first contacting the first guide part 601 of the core mold 6. Because the surface of the first guide part 601 is conical, its special shape guides the material, allowing it to flow smoothly along the processing direction and preventing accumulation or chaotic flow within the cavity 4. As the material continues to flow, it reaches the second guide part 602, which also has a conical surface, further guiding the material and ensuring it flows accurately towards the extrusion channel 5. Finally, the material smoothly enters the extrusion channel 5 and cooperates with the extrusion molding part 604 to complete the extrusion molding process.

[0057] like Figure 3 and Figure 10 As shown, in this embodiment, the cavity 4 is a funnel-shaped cavity that gradually narrows along the forming direction, with its smaller opening end fitting with the die 2. Because the cavity 4 in this embodiment is designed as a funnel-shaped cavity that gradually narrows along the forming direction, and its smaller opening end fits with the die 2, when the material enters the cavity 4, as it flows forward within the cavity 4, the gradually narrowing space causes the material to be subjected to a squeezing force from the sidewalls of the cavity 4, causing the material to aggregate more tightly and guiding it towards the smaller opening end that fits with the die 2. During this flow, the material is continuously compressed and shaped, gradually conforming to the shape and density requirements of subsequent extrusion molding. Finally, the material smoothly enters the die 2 through the smaller opening end of the cavity 4, and then enters the subsequent extrusion channel 5 and other structures for the final extrusion molding operation.

[0058] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific implementation method of this utility model and is not intended to limit this utility model. Any modifications, equivalent substitutions, and improvements made within the scope of the spirit of this utility model should be included within the protection scope of this utility model.

Claims

1. A precision thin-walled tube extrusion die, characterized in that, Along the processing and forming direction, it includes a compression mold (1), a die (2), and a shaping mold (3) that are fixedly connected in sequence; the compression mold (1) has a cavity (4) inside; it also includes an extrusion channel (5), which passes through the die (2) and the shaping mold (3) and communicates with the cavity (4); it also includes a core mold (6) and a fixing seat (7), which is fixed inside the cavity (4); one end of the core mold (6) is connected to the fixing seat (7), and the other end extends into the extrusion channel (5) and is suspended; there are two or more extrusion channels (5), and the number of core molds (6) corresponds to the number of extrusion channels (5).

2. The precision thin-walled tube extrusion die according to claim 1, characterized in that, A guide mold (8) is fixedly connected to the end face of the die (2) that mates with the compression mold (1). The guide mold (8) has a horn-shaped guide opening (9) in the middle that communicates with the extrusion channel (5). The larger end of the horn-shaped guide opening (9) faces the cavity (4), and the smaller end has the channel entrance (10) of the extrusion channel (5). A flow divider (11) is also fixedly connected inside the horn-shaped guide opening (9) to separate the entrance of the extrusion channel (5).

3. The precision thin-walled tube extrusion die according to claim 1 or 2, characterized in that, The core mold (6) includes a first guide part (601), a second guide part (602), a fixing part (603), and an extrusion molding part (604); the first guide part (601), the second guide part (602), and the fixing part (603) are all disposed in the cavity (4), and the extrusion molding part (604) is located in the extrusion channel (5) and suspended; the first guide part (601) and the second guide part (602) are respectively located at both ends of the fixing part (603), the first guide part (601) is located at the end away from the die (2), and the second guide part (602) is located between the fixing part (603) and the extrusion molding part (604); the surfaces of the first guide part (601) and the second guide part (602) are both conical surfaces, used to guide the material to flow along the processing molding direction.

4. The precision thin-walled tube extrusion die according to claim 3, characterized in that, The fixing seat (7) includes a sleeve (701) and a fixing ring (702). The fixing ring (702) is disposed outside the sleeve (701) and is fixedly connected to the inside of the cavity (4). The fixing part (603) is embedded in the sleeve (701) and is fixedly connected to the sleeve (701).

5. The precision thin-walled tube extrusion die according to claim 1, 2, or 4, characterized in that, The cavity (4) is a trumpet-shaped cavity whose inner cavity gradually decreases in size along the processing and forming direction, and its smaller opening end is matched with the die (2).

6. The precision thin-walled tube extrusion die according to claim 3, characterized in that, The cavity (4) is a trumpet-shaped cavity whose inner cavity gradually decreases in size along the processing and forming direction, and its smaller opening end is matched with the die (2).

7. The precision thin-walled tube extrusion die according to claim 1, 2, 4 or 6, characterized in that, Cooling channels (12) are provided on the shaping mold (3) for product cooling and shaping.

8. The precision thin-walled tube extrusion die according to claim 1, 2, 4 or 6, characterized in that, It also includes a barrel (13), which is fixedly connected to the compression mold (1) via a flange (14).

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