A barrel structure for a screw extruder

Abstract

This utility model relates to the field of screw extruder technology, and more particularly to a barrel structure for a screw extruder, comprising several unit barrels connected to adjacent unit barrels by bolts. Each unit barrel includes an inner barrel, an outer barrel, and an electromagnetic spiral heater. The inner barrel consists of a barrel segment and flanges at both ends, with the barrel segment and flanges sharing an extrusion channel. The flanges have bolt holes and inner and outer annular sealing grooves. The outer barrel is formed by the joining of two clamping half-barrels, with two symmetrical clamping grooves. The electromagnetic spiral heater includes a spiral body and terminals at both ends, with the spiral body positioned within the annular heating zone formed by the outer barrel and barrel segment. This utility model, through its innovative modular electromagnetic heating barrel, double sealing, and split structure, achieves precise temperature control, efficient sealing, and flexible configuration, making it suitable for demanding polymer processing scenarios. Its overall performance surpasses that of traditional extruder barrel designs.

Description

Technical Field

[0001] This utility model relates to the field of screw extruder technology, and in particular to a barrel structure for a screw extruder. Background Technology

[0002] The main advantages of using a modular barrel structure in screw extruders lie in their high flexibility and process optimization capabilities. Traditional fixed barrel structures are difficult to adjust once designed, while modular barrels allow engineers to flexibly adjust the arrangement of barrel modules or replace functional sections (such as feed, melting, and mixing sections) according to different material properties and processing requirements. This optimizes temperature distribution, shear strength, and mixing effects, significantly improving product quality and production efficiency. Modular barrel structures reduce equipment modification costs; no complete barrel replacement is required, only partial adjustments to adapt to new process requirements, reducing downtime and metal processing costs. This modular design also facilitates maintenance and cleaning, extending equipment lifespan, while providing more experimental possibilities for developing new materials, such as testing the impact of different process parameters on blend properties through rapid barrel module replacement.

[0003] The existing barrel structure used in screw extruders has several shortcomings. First, the flanges between the unit barrels lack internal supports, resulting in inadequate sealing between the flanges. Second, the unit barrels themselves lack temperature control components, preventing the adjustment of their heating temperature range according to process requirements. Therefore, the existing barrel structure for screw extruders needs to be optimized and improved. Summary of the Invention

[0004] The purpose of this invention is to overcome the aforementioned problems in the traditional technology and provide a barrel structure for a screw extruder.

[0005] To achieve the above-mentioned technical objectives and effects, this utility model is implemented through the following technical solution: A barrel structure for a screw extruder includes several unit barrels, with adjacent unit barrels connected by bolts; the unit barrels include: The inner cylinder is composed of a cylinder segment and flanges located at both ends thereon. The cylinder segment and the flanges are provided with an extrusion channel. The flanges are provided with a number of bolt holes along the circumferential direction near the outer edge. The flanges are provided with an inner annular sealing groove and an outer annular sealing groove between the extrusion channel and the bolt holes. The outer cylindrical component is formed by joining two clamping half-cylinders together, and the outer cylindrical component has two clamping through grooves symmetrically opened on the joining surfaces of the two clamping half-cylinders. An electromagnetic spiral heater, comprising a spiral body and terminals at both ends thereof, wherein the spiral body is disposed in an annular heating zone enclosed by an outer cylinder and a cylinder section, and the specifications of the terminals are matched with the specifications of the corresponding clamping grooves.

[0006] Furthermore, in the above-mentioned barrel structure for a screw extruder, the cross-sections of both the inner annular sealing groove and the outer annular sealing groove are semi-circular.

[0007] Furthermore, in the above-mentioned barrel structure for a screw extruder, the two clamping half-cylinders of the outer barrel are connected as a whole by welding.

[0008] Furthermore, in the aforementioned cylinder structure for a screw extruder, the two ends of the outer cylinder are respectively connected to the two flanges of the inner cylinder by spot welding.

[0009] Furthermore, in the above-mentioned barrel structure for a screw extruder, the outer diameter of the outer barrel is equal to the outer diameter of the outer annular sealing groove, and the inner diameter of the outer barrel is equal to the inner diameter of the outer annular sealing groove.

[0010] Furthermore, in the aforementioned cylinder structure for a screw extruder, the outer cylinder is provided with a pressure relief hole for easy pressure release.

[0011] Furthermore, in the above-mentioned barrel structure for a screw extruder, there are three unit barrels, which are respectively fitted outside the feeding section, compression section, and metering section of the extrusion screw.

[0012] Furthermore, in the above-mentioned barrel structure for a screw extruder, the inner barrel section is made of a material that can be electromagnetically heated.

[0013] The beneficial effects of this utility model are: 1. Modular unit tube design, adaptable to three-section functional requirements. The three unit cylinders correspond to the feeding section, compression section, and metering section, respectively. Their axial length matches the functional sections of the screw, allowing for independent temperature control of each section (e.g., low-temperature anti-bridging in the feeding section, high-temperature homogenization in the metering section). An electromagnetic spiral heater is integrated into the annular heating zone, directly heating the inner cylinder (electromagnetic induction material), resulting in rapid heating and high thermal efficiency, avoiding the lag inherent in traditional resistance heating. A pressure relief hole design balances the internal pressure of the annular heating zone, preventing deformation and damage to the outer cylinder. The unit cylinders are connected by bolts, facilitating disassembly, replacement, or sequence adjustment (e.g., when process requirements change), offering greater flexibility compared to traditional integral cylinder designs.

[0014] 2. Double sealing structure ensures stability under high temperature and high pressure. The inner and outer annular sealing grooves (semi-circular cross-section) work in conjunction with O-rings to create a self-tightening seal under fluid pressure, preventing molten material leakage. The outer sealing ring further isolates external contaminants. The sealing ring material can be TPU or rubber, offering high temperature resistance and tolerance compensation. The outer cylinder is integrally formed by welding and spot-welded to the inner cylinder flange, reducing the risk of seal failure due to thermal deformation. The sealing groove and cylinder dimensions are strictly matched (outer diameter / inner diameter equal), ensuring assembly accuracy. The outer cylinder provides internal support for the flanges on both sides, further guaranteeing sealing reliability.

[0015] 3. Co-optimization of electromagnetic heating and structure The electromagnetic spiral heater acts directly on the inner cylinder, utilizing the limited penetration depth of electromagnetic waves (infrared heating principle) to achieve rapid localized heating with lower energy consumption than traditional heating methods. The terminals and clamping slots are matched, simplifying installation and ensuring circuit stability. The inner cylinder material can be selected based on its electromagnetic response characteristics for different materials (such as TPU and PVC), and combined with three-stage temperature control (e.g., 150–210℃ gradient) to optimize the plasticizing effect. The split design of the outer cylinder (clamping half-cylinder) facilitates heater maintenance or replacement.

[0016] Of course, any product implementing this utility model does not necessarily need to achieve all of the above advantages at the same time. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, 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.

[0018] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is an assembly diagram of the combined use of this utility model; Figure 3 This is a schematic diagram of the inner cylinder component in this utility model; Figure 4 This is a half-sectional schematic diagram of the inner cylinder component in this utility model; Figure 5 This is a schematic diagram of the structure of the outer cylindrical component in this utility model; Figure 6 This is a schematic diagram of the electromagnetic spiral heater in this utility model; In the attached diagram, the components represented by each number are as follows: 1-Inner cylinder component, 101-Cylinder section, 102-Flange, 103-Extrusion channel, 104-Bolt perforation, 105-Inner annular sealing groove, 106-Outer annular sealing groove; 2-Outer cylinder, 201-Clamping half cylinder, 202-Clamping through groove; 3-Electromagnetic spiral heater. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0020] like Figures 1-6 As shown, this embodiment provides a barrel structure for a screw extruder, including several unit barrels, with adjacent unit barrels connected by bolts. Each unit barrel includes an inner barrel 1, an outer barrel 2, and an electromagnetic spiral heater 3. An inner sealing ring and an outer sealing ring for improving sealing effect are clamped and installed between adjacent unit barrels.

[0021] In this embodiment, the inner cylindrical component 1 is composed of a cylindrical section 101 and flanges 102 located at both ends thereon. The cylindrical section 101 and the flanges 102 together have an extrusion channel 103. The flanges 102 have a plurality of bolt holes 104 circumferentially formed near their outer edges. An inner annular sealing groove 105 and an outer annular sealing groove 106 are formed between the extrusion channel 103 and the bolt holes 104 on the flanges 102. The cylindrical section 101 of the inner cylindrical component 1 is made of a material that can be electromagnetically heated.

[0022] In this embodiment, the outer cylinder 2 is formed by connecting two clamping half cylinders 201. The outer cylinder 2 has two clamping slots 202 symmetrically opened on the mating surfaces of the two clamping half cylinders 201.

[0023] In this embodiment, the electromagnetic spiral heater 3 includes a spiral body and terminals at both ends. The spiral body is disposed in the annular heating zone formed by the outer cylinder 2 and the cylinder section 101. The specifications of the terminals are matched with the specifications of the corresponding clamping groove 202.

[0024] In this embodiment, the cross-sections of both the inner annular sealing groove 105 and the outer annular sealing groove 106 are semi-circular.

[0025] In this embodiment, the two clamping half-cylinders 201 of the outer cylinder 2 are connected as a whole by welding. The two ends of the outer cylinder 2 are respectively connected to the two flanges 102 of the inner cylinder 1 by spot welding.

[0026] In this embodiment, the outer diameter of the outer cylinder 2 is equal to the outer diameter of the outer annular sealing groove 106, and the inner diameter of the outer cylinder 2 is equal to the inner diameter of the outer annular sealing groove 106.

[0027] In this embodiment, the outer cylinder 2 is provided with a pressure relief hole for easy pressure release.

[0028] In this embodiment, three unit cylinders are provided, respectively fitted outside the feeding section, compression section, and metering section of the extrusion screw. The axial length of each unit cylinder is matched with the length of its corresponding functional section. Figure 2 This is just an example and does not impose any restrictions on the length of the unit tube.

[0029] One specific application of this embodiment is as follows: the three unit cylinders correspond to the feeding section, compression section, and metering section, respectively, with their axial length matching the functional sections of the screw, enabling independent temperature control for each section (e.g., low-temperature anti-bridging in the feeding section, high-temperature homogenization in the metering section). The electromagnetic spiral heater is integrated into the annular heating zone, directly heating the inner cylinder (electromagnetic induction material), resulting in rapid heating and high thermal efficiency, avoiding the lag of traditional resistance heating. The pressure relief hole design balances the internal pressure of the annular heating zone, preventing deformation and damage to the outer cylinder. The unit cylinders are connected by bolts, facilitating disassembly, replacement, or sequence adjustment (e.g., when process requirements change), making it more flexible than traditional integral cylinders.

[0030] The inner and outer annular sealing grooves (semi-circular cross-section) work in conjunction with O-rings to create a self-tightening seal under fluid pressure, preventing molten material leakage. The outer sealing ring further isolates external contaminants. The sealing ring material can be TPU or rubber, offering high temperature resistance and tolerance compensation. The outer cylinder is integrally formed by welding and spot-welded to the inner cylinder flange, reducing the risk of seal failure due to thermal deformation. The sealing groove and cylinder dimensions are strictly matched (outer diameter / inner diameter equal), ensuring assembly accuracy. The outer cylinder provides internal support for the flanges on both sides, further guaranteeing sealing reliability.

[0031] The electromagnetic spiral heater acts directly on the inner cylinder, utilizing the limited penetration depth of electromagnetic waves (infrared heating principle) to achieve rapid localized heating with lower energy consumption than traditional heating methods. The terminals and clamping slots are matched, simplifying installation and ensuring circuit stability. The inner cylinder material can be selected based on its electromagnetic response characteristics for different materials (such as TPU and PVC), and combined with three-stage temperature control (e.g., 150–210℃ gradient) to optimize the plasticizing effect. The split design of the outer cylinder (clamping half-cylinder) facilitates heater maintenance or replacement.

[0032] Through innovative electromagnetic heating modular cylinder, double sealing and split structure, it achieves precise temperature control, efficient sealing and flexible configuration, and is suitable for high-requirement polymer processing scenarios. Its overall performance is superior to that of traditional extruder cylinder designs.

[0033] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to specific implementation methods. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A barrel structure for a screw extruder, comprising a plurality of unit barrels, wherein adjacent unit barrels are connected by bolts; characterized in that, The unit cylinder includes: The inner cylinder is composed of a cylinder segment and flanges located at both ends thereon. The cylinder segment and the flanges are provided with an extrusion channel. The flanges are provided with a number of bolt holes along the circumferential direction near the outer edge. The flanges are provided with an inner annular sealing groove and an outer annular sealing groove between the extrusion channel and the bolt holes. The outer cylindrical component is formed by joining two clamping half-cylinders together, and the outer cylindrical component has two clamping through grooves symmetrically opened on the joining surfaces of the two clamping half-cylinders. An electromagnetic spiral heater, comprising a spiral body and terminals at both ends thereof, wherein the spiral body is disposed in an annular heating zone enclosed by an outer cylinder and a cylinder section, and the specifications of the terminals are matched with the specifications of the corresponding clamping grooves.

2. The barrel structure for a screw extruder according to claim 1, characterized in that, Both the inner and outer annular sealing grooves have semi-circular cross-sections.

3. The barrel structure for a screw extruder according to claim 1, characterized in that, The two clamping half-cylinders of the outer cylinder are connected as one piece by welding.

4. The barrel structure for a screw extruder according to claim 1, characterized in that, The two ends of the outer cylinder are connected to the two flanges of the inner cylinder by spot welding.

5. A barrel structure for a screw extruder according to claim 1, characterized in that, The outer diameter of the outer cylinder is equal to the outer diameter of the outer annular sealing groove, and the inner diameter of the outer cylinder is equal to the inner diameter of the outer annular sealing groove.

6. The barrel structure for a screw extruder according to claim 1, characterized in that, The outer cylinder is provided with a pressure relief hole for easy pressure release.

7. A barrel structure for a screw extruder according to claim 1, characterized in that, There are three unit cylinders, which are respectively fitted on the outside of the feeding section, compression section and metering section of the extrusion screw.

8. A barrel structure for a screw extruder according to claim 1, characterized in that, The inner cylinder section is made of a material that can be electromagnetically heated.

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