Adjustable disassembly-free double-screw extruder die
By setting adjustment components on both sides of the die of the twin-screw extruder to adjust the number of discharge holes, the problems of coiling and strip breakage caused by uneven pressure are solved, improving production efficiency and safety, and reducing the cost of replacing the die.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- YINGKOU KANGHUI PETROCHEM
- Filing Date
- 2025-02-12
- Publication Date
- 2026-04-24
AI Technical Summary
During the processing of twin-screw extruders, the material flow rate and velocity are higher at the center of the die and lower on both sides, resulting in uneven pressure distribution and problems such as coiling, breakage, and inability to stretch the material, which affects production efficiency and safety. Furthermore, changing the die requires stopping the machine, increasing costs.
Design an adjustable twin-screw extruder die. By setting adjustment components on both sides of the die, the number of discharge holes can be adjusted without disassembly, the pressure distribution can be balanced, and problems such as coiling and breakage can be solved.
It improved production efficiency, reduced costs, avoided material waste and safety hazards caused by uneven pressure, and enabled flexible adjustment of different materials.
Smart Images
Figure CN224158837U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of twin-screw extruder technology, and more particularly to an adjustable, non-disassembly-required twin-screw extruder die. Background Technology
[0002] Twin-screw extruders are essential production equipment in modified plastics processing. They achieve the extrusion molding of plastic products through steps such as feeding, screw drive, plastic melting, extrusion, and control and adjustment. The extrusion process is the most crucial step in modified plastics processing. The principle involves feeding molten plastic into the extrusion section of the barrel, where it is conveyed and sheared by the twin screws. After pressure is built up at the die head, the plastic is extruded through the die's discharge port. A cooling system is typically installed at the extrusion port to rapidly cool and solidify the molten plastic, followed by stretching, cooling, and granulation to obtain plastic granules.
[0003] The principle and function of an extruder die: to change the direction of melt flow, transforming the flow of melt from a spiral motion to a linear motion; to form a specified cross-sectional shape, ensuring the extrudate forms a specified cross-sectional shape, which is one of the main functions of the die; to uniformly distribute the melt, with the die distribution cavity responsible for distributing the polymer melt flow into the die across the entire cross-section, ensuring uniform melt distribution; and to streamline the flow, with the guide channel ensuring the polymer melt flows into the final die outlet in a streamlined manner, ensuring a smooth extrusion process.
[0004] The die in a twin-screw extruder plays a crucial role in the extrusion process, ensuring the stability of the extruded material's shape, size, and quality. However, during extrusion, the material flow rate and velocity are relatively high at the center of the die, while the flow rate and velocity are relatively low on the sides of the die, which are furthest from the center. This results in uneven pressure distribution in the storage area between the die head and the die, especially at the sides, where the pressure is weakest. Consequently, the discharge speed from the side outlets is slower than in the center, making it difficult to draw the extruded material. Problems such as coiling, breakage, and inability to draw the extruded material frequently occur, affecting operator work, posing safety hazards, wasting materials, and impacting product output. Utility Model Content
[0005] The technical problem this application aims to solve is that during the extrusion process, the material flow rate and velocity are relatively high at the center of the die, while the material flow rate and velocity are relatively low on the sides of the die, which are furthest from the center. As a result, the internal pressure distribution in the storage area between the die head and the die is uneven, especially the pressure on the sides of the die is the weakest. This leads to a slower discharge speed from the discharge holes on the sides compared to the center, making it difficult to draw the extruded material. Problems such as curling, breakage, and inability to draw the extruded material frequently occur, affecting the operator's work, posing certain safety hazards to the operator, wasting materials, and also affecting output.
[0006] To overcome the above-mentioned defects, this application provides an adjustable, non-disassembly-required twin-screw extruder die, including a die body and adjusting components; one end of the die body is connected to the extruder die head, and the other end has multiple discharge holes for extruding materials; through holes are respectively opened on both sides of the die body, and the adjusting components are respectively disposed on both sides of the die body; the adjusting components are used to penetrate into the interior of the die body through the through holes and to seal some of the discharge holes.
[0007] Furthermore, the die body is provided with a single discharge hole.
[0008] Furthermore, all of the discharge holes are the same size, the same depth, and are evenly distributed.
[0009] Furthermore, the diameter of the discharge hole is smaller than the diameter of the internal cavity of the die body.
[0010] Furthermore, the diameter of the internal cavity of the die body gradually decreases from near the extruder die head to near the discharge hole.
[0011] Furthermore, the adjusting component is a nut, and the diameter of the nut is larger than the diameter of the discharge hole.
[0012] Furthermore, the length of the adjusting component inside the die body is capable of covering at least one of the discharge holes.
[0013] Furthermore, the extruder die head is connected to the perforated plate, and the perforated plate is connected to the extruder body.
[0014] The above-mentioned technical solution of this application has the following advantages:
[0015] The adjustable, non-disassembly-free twin-screw extruder die provided in this application features adjusting components positioned on both sides of the die body. These components penetrate the die body through through-holes on both sides, sealing off some of the discharge holes. The adjusting components can seal off discharge holes that do not require material extrusion, allowing for adjustment of the number of discharge holes on both sides of the die without stopping the machine to disassemble and replace the die. This solves problems such as coiling, breakage, and inability to stretch the die due to pressure differences between the sides and the center. Furthermore, the number of discharge holes can be adjusted promptly for different materials, eliminating the need for repeated machine shutdowns to replace different dies, significantly improving production efficiency and reducing costs. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0017] Figure 1 A front view of the adjustable, non-removable twin-screw extruder die provided in this application;
[0018] Figure 2 A side sectional view of the adjustable, non-removable twin-screw extruder die provided in this application.
[0019] Reference numerals in the attached drawings: 1. Die body; 2. Adjustment component; 3. Extruder die head; 4. Discharge hole; 5. Perforated plate; 6. Extruder body. Detailed Implementation
[0020] The specific embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this application, but are not intended to limit the scope of this application.
[0021] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0022] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0023] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized.
[0024] During extrusion, the significant pressure difference between the center and sides of the die causes the discharge speed from the side orifices to be slower than that from the center, making strand drawing difficult and frequently resulting in problems such as coiling, breakage, and inability to draw strands. This necessitates frequent machine shutdowns to replace different dies for testing. While this solution addresses these issues, it requires multiple dies and constant machine shutdowns during production to change dies based on extrusion results, severely impacting production efficiency. Furthermore, the use of multiple dies significantly increases manufacturing costs.
[0025] This application provides an adjustable, non-disassembly-free twin-screw extruder die, which allows adjustment of the number of discharge holes on both sides of the extruder die without disassembly. This solves problems such as coiling, breakage, and inability to stretch the die due to pressure differences between the sides and the center. Furthermore, it allows for timely adjustment of the number of discharge holes for different materials, eliminating the need to repeatedly replace different dies and reducing costs.
[0026] The specific embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this application, but are not intended to limit the scope of this application.
[0027] like Figure 1 and Figure 2 As shown in the figure, this application provides an adjustable, non-disassembly-required twin-screw extruder die, including a die body 1 and an adjusting component 2; one end of the die body 1 is connected to the extruder die head 3, and the other end has a plurality of discharge holes 4, which are used for extruding materials; through holes are respectively opened on both sides of the die body 1, and the adjusting component 2 is respectively disposed on both sides of the die body 1; the adjusting component 2 is used to penetrate into the interior of the die body 1 through the through holes and to seal some of the discharge holes 4.
[0028] By setting the adjusting components 2 on both sides of the die body 1, the adjusting components 2 pass through the through holes on both sides of the die body 1 to seal some of the discharge holes 4 on the die body 1. According to actual needs, the adjusting components 2 can seal the discharge holes 4 that do not need to be extruded. The number of discharge holes actually used for extruding material on both sides of the extruder die can be adjusted without stopping the machine to disassemble and replace the die. This solves the problems of curling, strip breakage, and inability to stretch strip caused by different pressures on both sides and the center of the die. Furthermore, the number of discharge holes can be adjusted in time for different materials without having to stop the machine to replace different dies, which greatly improves production efficiency and reduces costs.
[0029] like Figure 1 As shown, in some embodiments, the die body 1 has a single discharge hole 4.
[0030] In some embodiments, each of the discharge holes 4 is the same size, the same depth, and is evenly distributed.
[0031] In some embodiments, the diameter of the discharge hole 4 is smaller than the diameter of the internal cavity of the die body 1.
[0032] like Figure 2 As shown, in some embodiments, the diameter of the internal cavity of the die body 1 gradually decreases from near the extruder die head 3 to near the discharge hole 4.
[0033] In some embodiments, the adjusting component 2 is a nut, and the diameter of the nut is larger than the diameter of the discharge hole 4.
[0034] In some embodiments, the length of the adjusting member 2 inside the die body 1 is sufficient to cover at least one of the discharge holes 4.
[0035] like Figure 2 As shown, in some embodiments, the extruder die 3 is connected to the perforated plate 5, and the perforated plate 5 is connected to the extruder body 6.
[0036] Traditional dies typically have double rows of holes and very large cavities, leading to uneven pressure distribution within the die. Unlike traditional dies, this application uses a single row of holes with multiple uniformly spaced, identical-sized discharge holes of the same depth. The smaller die cavity facilitates material extrusion, preventing material buildup and subsequent decomposition. Furthermore, an adjustable nut is located on each side of the die, allowing adjustment of the number of discharge holes based on the material's pressure at the die head during extrusion. This balances the die pressure, ensuring uniform, stable, and continuous extruded strips. Moreover, when switching to different materials, there is no need to replace the die; simply adjusting the number of discharge holes based on the material's viscosity is sufficient to balance the die pressure.
[0037] After the material is melted, it is extruded through a twin-screw extruder and enters the extruder die head through a perforated plate. As it passes through the die head section, the die cavity gradually decreases in size, and the material flows towards the die after being pressurized. Similarly, the die cavity in this application also gradually decreases in size, and with limited storage space, the material is again pressurized and flows towards the die outlet. The bottom of the die has multiple identical discharge holes, and the material is divided into equal flow rates before exiting each hole, which are then extruded separately. This design, on the one hand, utilizes the dual pressure from the die head and die to rapidly increase the pressure of the material inside the die, allowing for smooth extrusion through each discharge hole. The simple die cavity design reduces material storage. Since the die is constantly kept at a high temperature, excessive material accumulation can cause decomposition and deterioration, especially in the production of colored materials, leading to color changes. On the other hand, it also simplifies die processing and makes the desired effect more effective.
[0038] An adjustable nut is located on each side of the die, connected to the discharge port. Its depth covers the fourth discharge hole on each side (the currently used KraussMaffei Φ75 twin-screw extruder has a total of 31 discharge holes per row, with a diameter of 4mm; therefore, the adjustable number of discharge holes is between 23 and 31). The screw diameter is slightly larger than the discharge hole diameter, allowing for the sealing of unnecessary discharge holes to prevent material leakage. When no adjustment is needed, all discharge holes are open. In actual production, the number of discharge holes can be adjusted at any time according to the extrusion state of the material, without stopping the machine to disassemble or replace the die, greatly improving production efficiency and reducing manufacturing costs. Furthermore, adjustments can be made at any time when changing to different materials, increasing the adjustability for verifying different production processes and improving production and R&D efficiency.
[0039] The adjustable, non-disassembly-free twin-screw extruder die provided in this application includes a die body and an adjustable nut. The die is connected to the extruder die head to complete the entire extrusion process. Figure 1 As can be seen, this application has a single discharge hole with 31 discharge holes of the same size and spacing; there are two adjustable nuts on both sides, which can adjust the number of discharge holes at any time according to the state of the extruded material strips, balance the pressure inside the die, and eliminate the need to change the die back and forth; the die cavity inside the die is small, which increases the die pressure while preventing material accumulation and avoiding decomposition and deterioration of excessive material accumulation.
[0040] The following description is based on specific embodiments.
[0041] Example 1
[0042] The adjustable, non-disassembly-free twin-screw extruder die provided in this application has 31 discharge orifices, each 4mm in diameter, and a production output of 1200 kg / hour. The produced product is reinforced flame-retardant PBT. Actual testing revealed that with 31 discharge orifices, the strips from the two outermost orifices were significantly thinner than those from the others, frequently resulting in strip breakage. Adjusting the number of discharge orifices to 29 resulted in uniform strip size and stable production across all orifices.
[0043] Example 2
[0044] Based on Example 1, another toughened PBT product was switched to, with a production output of 1000 kg per hour. According to actual tests, when the number of discharge holes was 31, the material strips from the six discharge holes on both sides of the die broke, affecting the traction of the middle section of the material strip. When the number of discharge holes was adjusted to 25, the material strips from all discharge holes were uniform, the particle size was moderate, and stable production was achieved.
[0045] Comparative Example
[0046] Using a commercially available conventional die with double rows of holes, it has a total of 41 discharge holes, each 3.5mm in diameter, with a production capacity of 1200 kg / hour. The product produced is reinforced flame-retardant PBT. According to actual testing, the feed strips from the 4-6 discharge holes on the outermost sides of the die are much thinner than those from other discharge holes, frequently resulting in broken strips. This necessitates machine shutdown. Replacing the die with one that has 35 discharge holes results in uniform feed strips and appropriately sized pellets, allowing for stable production. However, after 4 hours of stable production, occasional yellow filaments appear mixed in with the feed strips from the outermost discharge holes. Inspection at the pelletizing stage indicates that the product appearance is substandard, requiring machine shutdown and die cleaning. Switching to different product types requires further machine shutdown and die selection before production can resume.
[0047] As can be seen from the above two embodiments and comparative examples, the adjustable, non-disassembly-required twin-screw extruder die of this application can adjust the number of discharge orifices at any time according to the production situation and the state of the extruded material strips, thereby balancing the pressure inside the die. Furthermore, it eliminates the need for frequent die replacements, allowing for machine shutdown during daily production or product switching, significantly improving production efficiency. The small internal cavity of the die increases die pressure while preventing material accumulation, thus avoiding decomposition and spoilage due to excessive material buildup.
[0048] The adjustable, non-disassembly-free twin-screw extruder die provided in this application embodiment allows for adjustment of the number of discharge holes on both sides of the extruder die without stopping the machine to disassemble and replace the die. This solves problems such as coiling, strip breakage, and inability to stretch strips caused by pressure differences between the sides and the center of the die. Furthermore, the number of discharge holes can be adjusted in a timely manner for different materials, eliminating the need to stop the machine repeatedly to replace different dies, thus greatly improving production efficiency and reducing costs.
[0049] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. Furthermore, the specific names of the functional units and modules are only for easy distinction and are not intended to limit the scope of protection of this application.
[0050] It should be clarified that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. This application is not limited to the specific structures described above and shown in the figures. Furthermore, for the sake of brevity, detailed descriptions of known methods and techniques are omitted here.
[0051] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.
Claims
1. An adjustable, non-disassembly-free twin-screw extruder die, characterized in that, The device includes a die body and an adjusting component; one end of the die body is connected to the extruder die head, and the other end has multiple discharge holes for extruding materials; through holes are respectively opened on both sides of the die body, and the adjusting component is respectively disposed on both sides of the die body; the adjusting component is used to penetrate into the interior of the die body through the through holes and to seal some of the discharge holes.
2. The adjustable, non-disassembly-free twin-screw extruder die as described in claim 1, characterized in that, The die body has a single discharge hole.
3. The adjustable, non-disassembly-free twin-screw extruder die as described in claim 1, characterized in that, All the discharge holes are the same size, the same depth, and are evenly distributed.
4. The adjustable, non-disassembly-free twin-screw extruder die as described in claim 1, characterized in that, The diameter of the discharge hole is smaller than the diameter of the internal cavity of the die body.
5. The adjustable, non-disassembly-free twin-screw extruder die as described in claim 1, characterized in that, The diameter of the internal cavity of the die body gradually decreases from near the extruder die head to near the discharge hole.
6. The adjustable, non-disassembly-free twin-screw extruder die as described in claim 1, characterized in that, The adjusting component is a nut, and the diameter of the nut is larger than the diameter of the discharge hole.
7. The adjustable, non-disassembly-free twin-screw extruder die as described in claim 1, characterized in that, The length of the adjusting component inside the die body is sufficient to cover at least one of the discharge holes.
8. The adjustable, non-disassembly-free twin-screw extruder die as described in claim 1, characterized in that, The extruder die head is connected to the perforated plate, and the perforated plate is connected to the extruder body.