A double screw extruder with cooling function

Abstract

The utility model relates to double screw extruder technical field, and disclose a double screw extruder with cooling function, including workstation, be provided with the feeding cylinder on the workstation, the outside of feeding cylinder is provided with heating structure, the end of feeding cylinder has an outlet, is provided with cooling channel at the outlet, is provided with cooling pipe on cooling channel, and one end of cooling pipe is linked with the outlet, and the other end of cooling pipe extends to the outside of cooling channel, and the interval structure that is adapted to cooling pipe is provided in cooling channel, when the cooling medium flows through cooling channel, interval structure is used for slowing down the cooling medium flow rate, the utility model discloses can prevent moisture infiltration line material inside, and then improve the quality of line material product.

Description

Technical Field

[0001] This utility model relates to the technical field of twin-screw extruders, specifically a twin-screw extruder with a cooling function. Background Technology

[0002] A twin-screw extruder is an equipment developed from a single-screw extruder. With its superior feeding performance, mixing and plasticizing effect, venting efficiency, and extrusion stability, it is now widely used in the molding and processing of extruded products. This equipment mainly consists of a transmission device, feeding device, barrel, and screws. The functions of each component are similar to those of a single-screw extruder. The core difference lies in the fact that the twin-screw extruder has two parallel screws arranged side-by-side inside the "∞"-shaped cross-section barrel.

[0003] Currently, for the application of plastic pellets, after the existing twin-screw extruder extrudes cylindrical plastic filaments, the material is still in a high-temperature molten state and needs to be cooled and hardened before pelletizing. The common cooling method is to cool the filaments with water through a rectangular water tank. However, when the high-temperature filaments first come into contact with water, due to the surface condition (such as micropores and stress caused by temperature gradients), moisture may easily penetrate into the interior, thus affecting product quality.

[0004] Therefore, existing technologies have shortcomings and need to be improved. Utility Model Content

[0005] This invention provides a twin-screw extruder with a cooling function. By combining a cooling channel, a cooling pipe, and a spacer structure, the cooling medium can indirectly exchange heat outside the pipe, thus solving the problem mentioned in the background art where moisture easily seeps into the interior and affects product quality.

[0006] This utility model provides the following technical solution:

[0007] A twin-screw extruder with a cooling function includes a worktable, a feed cylinder on the worktable, a heating structure on the outside of the feed cylinder, an outlet at the end of the feed cylinder, a cooling channel at the outlet, a cooling pipe on the cooling channel, one end of the cooling pipe being connected to the outlet, and the other end of the cooling pipe extending to the outside of the cooling channel, and a partition structure adapted to the cooling pipe being provided inside the cooling channel, the partition structure being used to slow down the flow rate of the cooling medium when the cooling medium flows through the cooling channel.

[0008] As a preferred embodiment of this utility model, a flow divider is provided at the outlet of the feeding cylinder, the flow divider has a flow dividing cavity, the flow dividing cavity of the flow divider is connected to the cooling channel, and the feed end of the cooling pipe is connected to the flow divider.

[0009] As a preferred embodiment of this utility model, the cooling channel is provided with an inlet pipe and an outlet pipe that are connected to the distribution chamber.

[0010] As a preferred embodiment of this utility model, the spacer structure is provided with through holes.

[0011] As a preferred embodiment of this utility model, a feeding hopper is provided on the workbench, a conveying pipe is provided on the feeding hopper, a conveying component is provided on the conveying pipe, and the conveying pipe is connected to the conveying cylinder.

[0012] As a preferred embodiment of this utility model, a control panel is provided on the workbench.

[0013] Compared with the prior art, this utility model provides a twin-screw extruder with a cooling function, which has the following beneficial effects:

[0014] 1. In this twin-screw extruder with cooling function, the wire material can be conveyed in a sealed manner through the cooling pipe. The cooling medium indirectly exchanges heat outside the pipe, which structurally cuts off the contact path between moisture and wire material. At the same time, the design of the partition structure not only slows down the flow rate of the medium and improves the heat exchange efficiency, but also avoids equipment vibration caused by the impact of the medium, ensuring the forming accuracy of the wire material, preventing moisture from seeping into the interior of the wire material, and thus improving product quality.

[0015] The parts of this device not covered herein are the same as or can be implemented using existing technologies. This utility model can prevent moisture from seeping into the interior of the thread material, thereby improving product quality. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art 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.

[0017] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this utility model. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0018] Figure 1 This is a schematic diagram of the entire utility model;

[0019] Figure 2 This is a schematic diagram of the material conveying cylinder of this utility model;

[0020] Figure 3 This is a schematic diagram of the cooling channel of this utility model;

[0021] Figure 4 This is a schematic diagram of the spacer structure of this utility model.

[0022] In the diagram: 100, workbench; 101, control panel; 200, feed cylinder; 201, distributor; 202, gearbox; 300, heating structure; 400, cooling channel; 401, liquid inlet pipe; 402, liquid outlet pipe; 500, cooling pipe; 600, partition structure; 601, through hole; 700, feed hopper; 701, conveying pipe; 702, conveying component. Detailed Implementation

[0023] To make the utility model's objectives, features, and advantages more apparent and understandable, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below 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 scope of protection of the present utility model.

[0024] In the description of this utility model, it should be understood that the terms "upper," "lower," "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 utility model 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 of this utility model. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component centrally located at the same time.

[0025] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0026] Reference Figures 1-4This utility model provides a twin-screw extruder with a cooling function. Its basic component, the main support module, is centered on the workbench 100, which is welded from high-strength alloy steel. The bottom is equipped with leveling pads (unmarked) to ensure the stability of the equipment during operation and to prevent vibration from affecting the material conveying accuracy. The core components are arranged in functional zones on the top panel of the workbench 100. One end of the material extrusion module's conveying cylinder 200 is fixedly installed, and the other end integrates the control panel 101 of the control module. The control panel 101 adopts a touch-screen operation interface and has a built-in PLC control system. It can be used to display and adjust key parameters such as heating temperature, cooling medium flow rate, screw speed, and conveying component 702 speed. It also has fault alarm functions such as abnormal temperature and medium flow interruption. This is existing technology.

[0027] Specifically, a feeding assembly is provided, consisting of a feeding hopper 700, a conveying pipe 701, and a conveying component 702. The feeding hopper 700 adopts a funnel-shaped structure with a volume of 50L, and the inner wall is polished to prevent material adhesion. The conveying pipe 701 is a stainless steel round pipe, one end of which is welded to the bottom outlet of the feeding hopper 700, and the other end extends to the inlet of the conveying cylinder 200 and is sealed by a flange. The conveying component 702 is a screw feeder, which is installed inside the conveying pipe 701 and is driven by a micro stepper motor. The speed can be adjusted through the control panel 101 to achieve quantitative and uniform material conveying and avoid local overheating or extrusion fluctuations caused by uneven feeding.

[0028] Reference Figure 2 The feeding cylinder 200 has an "∞" shaped cross-section channel with nitrided inner walls to improve wear resistance. Two meshing twin screws are arranged parallel inside. The screws employ a modular, building-block design, including a feeding section, a mixing section, a plasticizing section, and a venting section. A transmission unit, mainly consisting of a gearbox 202 and a servo motor, is also installed on the worktable 100 to drive the two screws to rotate synchronously in opposite directions. The speed adjustment range is 50-300 r / min. The heating structure 300 uses a segmented electric heating jacket, with four groups evenly arranged axially along the outer wall of the feeding cylinder 200. A protective cover is fitted over the segmented electric heating jacket. Each group has a heating power of 3kW. The heating jacket fits tightly against the outer wall of the feeding cylinder 200, and each group is equipped with an independent temperature sensor. Segmented temperature control can be achieved through the control panel 101, with a temperature control range of 80-300℃.

[0029] Specifically, a distributor 201 is fixedly installed at the discharge end of the conveying cylinder 200 via a flange. The distributor 201 is made of stainless steel forging, has a distribution cavity inside, and is connected to the outlet of the conveying cylinder 200 to receive molten wire. The other end is sealed to the inlet end of the cooling pipe 500, and the distributor 201 is connected to the inlet of the cooling channel 400.

[0030] It should be explained that a cooling module is also provided in this device, which is the core innovation of this embodiment, namely the cooling channel 400. It adopts a stainless steel sleeve structure, with one end connected to the distributor 201 and the other end extending to the outside of the workbench 100. The side walls of the cooling channel 400 are respectively connected to the inlet pipe 401 and the outlet pipe 402. The outlet pipe 402 is located at the end closer to the distributor 201 and is connected to the outlet of an external cooling medium circulation system such as a chiller. It is used to introduce industrial soft water, a commonly used low-temperature cooling medium, with the temperature controlled at 15-25℃. The inlet pipe 401 is located at the end away from the distributor 201 and is connected to the return port of the circulation system to form a "medium circulation loop". Both the inlet pipe 401 and the outlet pipe 402 are equipped with flow regulating valves (not shown in the figure), which are automatically adjusted by the control panel 101 according to the temperature feedback.

[0031] Specifically, a cooling pipe 500 is also installed on the cooling channel 400. It is a high-strength quartz glass tube or stainless steel tube with a length consistent with the length of the cooling chamber of the cooling channel 400. One end of the cooling pipe 500 is connected to the distributor 201 to ensure that the molten wire can be sealed into the cooling pipe 500. The other end passes through the cooling channel 400 and extends 50mm to the outside to facilitate the subsequent pelletizing process. The entire cooling pipe 500 is suspended and fixed inside the cooling channel 400, maintaining a gap of 10-15mm with the inner wall of the cooling channel 400 to accommodate the cooling medium.

[0032] A spacer structure 600 is also provided within the cooling channel 400. This spacer structure is made of annular stainless steel plate, with its outer diameter matching the inner diameter of the cooling chamber of the cooling channel 400 and its inner diameter closely fitting the outer diameter of the cooling pipe 500. It is fixed to the cooling pipe 500 by welding. Three to eight groups of spacer structures 600 are evenly arranged along the axial direction of the cooling pipe 500; in this device, there are six groups. Each group has 2 to 6 through holes 601 evenly distributed on its annular plate; in this device, there are four. The diameter of the through holes 601 is [not specified]. The diameter is 5-8mm, and in this device it is 6mm. Its core function is that when the cooling medium enters the cooling channel 400 from the inlet pipe 401, it must pass through the through hole 601 of the spacer structure 600 to flow along the channel. The flow restriction effect of the through hole 601 can slow down the medium flow rate from the original 0.8-1.2m / s to 0.3-0.5m / s, prolong the heat exchange time between the medium and the cooling pipe 500, and at the same time avoid the high-speed medium impact causing the cooling pipe 500 to vibrate, ensuring the smooth conveying of the wire material.

[0033] The working principle is as follows:

[0034] Preheating and parameter setting: Start the equipment via control panel 101, set the temperature of each section of heating structure 300 (e.g., 180-200℃ for PE material), twin screw speed 100r / min, conveying component 702 speed 5r / min, and cooling medium temperature 20℃ and flow rate 10L / min. Start the heating system and cooling medium circulation system. Once the temperature of each section of conveying cylinder 200 reaches the set value and stabilizes, the equipment will enter the working state.

[0035] Material conveying and mixing / plasticizing: Plastic raw materials, such as PE granules, are poured into the feeding hopper 700. The conveying component 702 is started, and the screw feeder quantitatively conveys the raw materials to the feed end of the conveying cylinder 200. The twin screws rotate synchronously in opposite directions, and the thrust of the screws pushes the raw materials forward along the conveying cylinder axis. During the pushing process, the raw materials are subjected to shearing and extrusion forces between the screws and the cylinder wall, generating frictional heat. Combined with the external heating of the heating structure 300, the raw materials gradually melt from a solid state to a uniform molten state. In the mixing and plasticizing sections, the meshing structure of the twin screws can achieve thorough mixing of the materials and ensure uniform composition. At the same time, an exhaust section is also provided on the conveying cylinder 200 to discharge volatiles and moisture in the materials through the exhaust port. This is not shown in the figure and is existing technology.

[0036] The purified molten plastic wire enters the distribution chamber of the distributor 201 from the outlet of the feed cylinder 200, and then enters the interior of the cooling pipe 500. At the same time, the low-temperature cooling medium 20°C soft water of the external circulation system enters the cooling chamber of the cooling channel 400 through the inlet pipe 401. Due to the obstruction of the partition structure 600, the medium needs to flow slowly through the through hole 601 on the annular plate. During the flow, it fully contacts the outer wall of the cooling pipe 500 and carries away the heat of the molten wire in the cooling pipe 500 through heat conduction. The molten wire is continuously transported forward in the cooling pipe 500. The heat conduction of the pipe wall causes the wire temperature to gradually decrease from 200°C to below 60°C, and finally solidifies into solid wire at the outlet of the cooling pipe 500. Because the cooling pipe 500 is sealed throughout, the cooling medium does not come into direct contact with the wire, and water seepage is completely avoided.

[0037] After solidification, the solidified wire extends from the cooling pipe 500 to the external outlet, completing the entire extrusion-cooling-forming process. During operation, the control panel 101 can monitor the temperature of the feeding cylinder 200, the inlet and outlet temperatures of the cooling medium, and the wire discharge temperature in real time. When the wire temperature is detected to be too high, the cooling medium flow rate is automatically increased; when the temperature is too low, the flow rate is reduced to ensure stable cooling effect. This is existing technology. After the raw material is conveyed, the feed inlet of the feeding hopper 700 is closed. After the material in the feeding cylinder is emptied, the temperature of the heating structure 300 is gradually reduced. Reduce the screw speed and cooling medium flow rate. After the equipment temperature drops to room temperature, turn off the main power supply and clean the feeding hopper 700, conveying pipe 701, and cooling channel 400 to prevent residual material from clumping. This allows the wire material to be conveyed in a sealed manner through the cooling pipe 500. The cooling medium indirectly exchanges heat outside the pipe, structurally cutting off the contact path between moisture and the wire material. At the same time, the design of the partition structure 600 not only slows down the medium flow rate and improves the heat exchange efficiency, but also avoids equipment vibration caused by medium impact, ensuring the wire material forming accuracy, preventing moisture from seeping into the wire material, and thus improving product quality.

[0038] Components not described in detail in this article are existing technologies and will not be elaborated upon here.

[0039] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model 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 utility model.

Claims

1. A twin-screw extruder with a cooling function, comprising a worktable (100), characterized in that, A feed cylinder (200) is provided on the workbench (100). A heating structure (300) is provided on the outside of the feed cylinder (200). The end of the feed cylinder (200) has an outlet. A cooling channel (400) is provided at the outlet. A cooling pipe (500) is provided on the cooling channel (400). One end of the cooling pipe (500) is connected to the outlet. The other end of the cooling pipe (500) extends to the outside of the cooling channel (400). A partition structure (600) adapted to the cooling pipe (500) is provided inside the cooling channel (400). When the cooling medium flows through the cooling channel (400), the partition structure (600) is used to slow down the flow rate of the cooling medium.

2. A twin-screw extruder with cooling function according to claim 1, characterized in that, A flow divider (201) is provided at the outlet of the feed cylinder (200). The flow divider (201) has a flow dividing cavity. The flow dividing cavity of the flow divider (201) is connected to the cooling channel (400). The feed end of the cooling pipe (500) is connected to the flow divider (201).

3. A twin-screw extruder with cooling function according to claim 2, characterized in that, The cooling channel (400) is provided with an inlet pipe (401) and an outlet pipe (402) that are connected to the flow distribution chamber.

4. A twin-screw extruder with cooling function according to claim 1, characterized in that, The spacer structure (600) is provided with a through hole (601).

5. A twin-screw extruder with cooling function according to claim 1, characterized in that, The workbench (100) is provided with a feeding hopper (700), the feeding hopper (700) is provided with a conveying pipe (701), the conveying pipe (701) is provided with a conveying component (702), and the conveying pipe (701) is connected to the conveying cylinder (200).

6. A twin-screw extruder with cooling function according to claim 5, characterized in that, A control panel (101) is provided on the workbench (100).

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