Melt extrusion system

Abstract

The invention relates to a melt extrusion system which is characterized in that a first feeding unit comprises a first screening device and a first quantitative feeding device, the output end of the first screening device is connected with the input end of the first quantitative feeding device, and a second feeding unit comprises a second screening device and a second quantitative feeding device; the output end of the second screening device is connected with the input end of the second quantitative feeding device, and the input end of the raw material extrusion unit is connected with the output end of the first quantitative feeding device and the output end of the second quantitative feeding device. According to the melt extrusion system, the second impurity cleaner and the second vibrating screen are additionally arranged in the melt extrusion system, hardened antioxidants and impurities in the antioxidants are removed in a targeted mode, and the influence of the hardened antioxidants and the impurities on the stability of the melt extrusion process and the quality and performance of products is eliminated; therefore, the stability of the melt extrusion process is improved.

Description

Technical Field

[0001] The present invention relates to the field of polymer processing technology, and in particular to a melt extrusion system. Background Art

[0002] Cross-linked polyethylene (XLPE) is a widely used thermoplastic, commonly used in power cables and other electrical insulation materials. In the production of cross-linked polyethylene, it is crucial to ensure batch stability, which is closely related to the performance and quality of the final product. Melt extrusion is one of the key processes for preparing cross-linked polyethylene (XLPE) insulation materials. However, in the actual production process, due to changes in factors such as raw materials and process parameters, the stability of the melt extrusion process is affected, which in turn easily affects the quality and performance of the product. Therefore, how to improve the batch stability of cross-linked polyethylene melt extrusion is particularly important. Summary of the invention

[0003] Based on this, it is necessary to provide a melt extrusion system to address the above-mentioned technical problem of how to improve the melt extrusion stability of cross-linked polyethylene.

[0004] The present application provides a melt extrusion system, the melt extrusion system comprising:

[0005] A first feeding unit, the first feeding unit comprising a first screening device and a first quantitative feeding device, the first screening device is used to receive and screen the first raw material according to the first screening standard, the output end of the first screening device is connected to the input end of the first quantitative feeding device, and is used to transport the screened first raw material to the first quantitative feeding device;

[0006] A second feeding unit, the second feeding unit comprising a second screening device and a second quantitative feeding device, the second screening device is used to receive and screen the second raw material according to the second screening standard, the output end of the second screening device is connected to the input end of the second quantitative feeding device, and is used to transport the screened second raw material to the second quantitative feeding device;

[0007] A raw material extrusion unit, the input end of which is connected to the output end of the first quantitative feeding device and the output end of the second quantitative feeding device, and is used for quantitatively receiving the screened first raw material and the second raw material.

[0008] In one embodiment, the melt extrusion system comprises:

[0009] A pelletizing unit, wherein the input end of the pelletizing unit is connected to the output end of the raw material extrusion unit;

[0010] A dehydration unit, wherein the input end of the dehydration unit is connected to the output end of the pelletizing unit.

[0011] In one embodiment, the pelletizing unit comprises:

[0012] An underwater pelletizing device, wherein the input end of the underwater pelletizing device is connected to the output end of the raw material extrusion unit, the output end of the underwater pelletizing device is connected to the input end of the dehydration unit, and the underwater pelletizing device and the dehydration unit are both provided with a reflux end;

[0013] A fluid delivery pipeline, the fluid delivery pipeline comprising a first pipeline section and a second pipeline section, the first pipeline section connecting the output end of the underwater pelletizing device and the input end of the dehydration unit, and the second pipeline section connecting the return end of the dehydration unit and the return end of the underwater pelletizing device;

[0014] A fluid delivery pump body, wherein the fluid delivery pump body is arranged in the second pipeline section;

[0015] A pure water filter device, which is arranged in the second pipeline section and located between the underwater pelletizing device and the fluid delivery pump body;

[0016] A conductivity testing device is provided in the fluid delivery pipeline.

[0017] In one embodiment, the fluid delivery pipeline is set to have a first position, a second position and a third position, wherein the first position is located in the first pipeline section, the second position and the third position are located in the second pipeline section, and the second position is located between the underwater pelletizing device and the pure water filtration device, and the third position is located between the fluid delivery pump body and the dehydration unit, and at least one of the first position, the second position and the third position is provided with at least one conductivity testing device.

[0018] In one embodiment, the melt extrusion system comprises:

[0019] a third screening device, wherein an input end of the third screening device is connected to an output end of the dehydration unit;

[0020] A heat-insulating material storage device, wherein the input end of the heat-insulating material storage device is connected to the output end of the third screening device.

[0021] In one embodiment, the melt extrusion system comprises:

[0022] The third feeding unit comprises a third storage device and a third quantitative feeding device. The third storage device is used to store a third raw material. The output end of the third storage device is connected to the input end of the third quantitative feeding device.

[0023] In one embodiment, the melt extrusion system comprises:

[0024] A shaking can device, wherein the input end of the shaking can device is connected to the output end of the heat-insulating material storage device and the output end of the third quantitative feeding device.

[0025] In one embodiment, the melt extrusion system comprises:

[0026] A heat preservation device, wherein the input end of the heat preservation device is connected to the output end of the shaking pot device.

[0027] In one embodiment, the melt extrusion system comprises:

[0028] A cooling device, wherein the input end of the cooling device is connected to the output end of the heat preservation device.

[0029] In one embodiment, the melt extrusion system further comprises a blending and stirring device, the input end of the blending and stirring device is connected to the output end of the first quantitative feeding device and the output end of the second quantitative feeding device, the output end of the blending and stirring device is connected to the input end of the raw material extrusion unit, and the input end of the raw material extrusion unit is indirectly connected to the output end of the first quantitative feeding device and the output end of the second quantitative feeding device through the blending and stirring device; and / or,

[0030] The first feeding unit further comprises a first storage device, the first storage device is used to store the first raw material, the output end of the first storage device is connected to the input end of the first screening device; and / or,

[0031] The second feeding unit further comprises a second storage device, the second storage device is used to store the second raw material, the output end of the second storage device is connected to the input end of the second screening device; and / or,

[0032] The first screening device comprises a first impurity cleaner and a first vibrating screen, wherein an input end of the first impurity cleaner is used to receive a first raw material, an output end of the first impurity cleaner is connected to an input end of the first vibrating screen, and an output end of the first vibrating screen is connected to an input end of the first quantitative feeding device; and / or,

[0033] The second screening device comprises a second impurity cleaner and a second vibrating screen, the input end of the second impurity cleaner is used to receive the second raw material, the output end of the second impurity cleaner is connected to the input end of the second vibrating screen, and the output end of the second vibrating screen is connected to the input end of the second quantitative feeding device; and / or,

[0034] The raw material extrusion unit includes a screw extruder, the input end of the screw extruder is connected to the output end of the first quantitative feeding device and the output end of the second quantitative feeding device, and the output end of the screw extruder is used to connect to the input end of the pelletizing unit, wherein the screw extruder is provided with a screw drive motor, a melt pump and a screen changer.

[0035] In the above-mentioned melt extrusion system, a second impurity cleaner and a second vibrating screen are added to the melt extrusion system to specifically remove the hardened antioxidant and impurities in the antioxidant. The base material and antioxidant obtained after being processed by the first feeding unit and the second feeding unit are then transported to the raw material extrusion unit for mixed extrusion processing and subsequent other processing processes. The influence of the hardened antioxidant and impurities on the stability of the melt extrusion process and the quality and performance of the product can be eliminated, thereby improving the stability of the melt extrusion process. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of the melt extrusion system provided in the first embodiment of the present application.

[0037] Figure 2 This is a schematic diagram of a melt extrusion system provided in the second embodiment of the present application.

[0038] Figure 3 This is a schematic diagram of the melt extrusion system provided in the third embodiment of the present application.

[0039] Figure 4 This is a schematic diagram of a melt extrusion system provided in the fourth embodiment of the present application.

[0040] Figure 5 This is a schematic diagram of a melt extrusion system provided in the fifth embodiment of the present application.

[0041] Figure Number:

[0042] 1000, first feeding unit; 2000, second feeding unit; 3000, raw material extrusion unit; 4000, pelletizing unit; 5000, dehydration unit;

[0043] 1100, a first material storage device; 1200, a first screening device; 1300, a first quantitative feeding device;

[0044] 2100, second material storage device; 2200, second screening device; 2300, second quantitative feeding device;

[0045] 3100, screw extruder; 3200, screw drive motor; 3300, melt pump; 3400, screen changer; 3500, blending and stirring device;

[0046] 4100, underwater pelletizing device; 4200, fluid delivery pipeline; 4300, fluid delivery pump body; 4400, pure water filtering device; 4500, conductivity testing device; 4201, first pipeline section; 4202, second pipeline section;

[0047] 6100, third screening device; 6200, heat preservation storage device; 6300, third feeding unit; 6400, shaking tank device; 6500, heat preservation device; 6600, cooling device;

[0048] 6310. A third material storage device; 6320. A third quantitative feeding device. DETAILED DESCRIPTION

[0049] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0050] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0051] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0052] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0053] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0054] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0055] See also Figure 1 As shown, the present application provides a melt extrusion system, which includes a first feeding unit 1000, a second feeding unit 2000 and a raw material extrusion unit 3000. The first feeding unit 1000 is used to convey the first raw material to the raw material extrusion unit 3000, and the second feeding unit 2000 is used to convey the second raw material to the raw material extrusion unit 3000, so that the first raw material and the second raw material processed by the first feeding unit 1000 and the second feeding unit 2000 can be concentrated in the raw material extrusion unit 3000 for extrusion processing. Among them, the first raw material can be selected as a low-density polyethylene base material (hereinafter referred to as the base material), and the second raw material can be selected as an antioxidant.

[0056] Continue reading Figure 1As shown, the first feeding unit 1000 includes a first screening device 1200 and a first quantitative feeding device 1300. The first screening device 1200 is used to receive and screen the first raw material according to the first screening standard. The output end of the first screening device 1200 is connected to the input end of the first quantitative feeding device 1300, and is used to transport the screened first raw material to the first quantitative feeding device 1300. The first raw material can be transported to the first screening device 1200 in a variety of ways. For example, the first feeding unit 1000 may also include a first storage device 1100. The first storage device 1100 is used to store the first raw material. The output end of the first storage device 1100 is connected to the input end of the first screening device 1200, thereby directly transporting the first raw material stored in the first storage device 1100 to the first screening device 1200. In addition, the first raw material can also be transported to the first screening device 1200 in other ways, which can be selected by those skilled in the art according to actual needs and are not limited here.

[0057] In one embodiment, the first screening device 1200 may include a first impurity cleaner and a first vibrating screen, the input end of the first impurity cleaner is used to receive the first raw material, the output end of the first impurity cleaner is connected to the input end of the first vibrating screen, and the output end of the first vibrating screen is connected to the input end of the first quantitative feeding device 1300. In this process, the first raw material (base material) can first pass through the first impurity cleaner, and the first impurity cleaner is used to clean the metal and dust impurities doped in the base material. The base material after the impurity cleaning is then screened by the first vibrating screen for particle size, and the particle size of the base material is normalized to remove samples whose particle size does not meet the requirements.

[0058] Continue reading Figure 1 As shown, the second feeding unit 2000 includes a second screening device 2200 and a second quantitative feeding device 2300. The second screening device 2200 is used to receive and screen the second raw material according to the second screening standard. The output end of the second screening device 2200 is connected to the input end of the second quantitative feeding device 2300, and is used to transport the screened second raw material to the second quantitative feeding device 2300. The second raw material can be transported to the second screening device 2200 in a variety of ways. For example, the second feeding unit 2000 may also include a second storage device 2100. The second storage device 2100 is used to store the second raw material. The output end of the second storage device 2100 is connected to the input end of the second screening device 2200, thereby directly transporting the second raw material stored in the second storage device 2100 to the second screening device 2200. In addition, the second raw material can also be transported to the second screening device 2200 in other ways. Those skilled in the art can choose according to actual needs, and it is not limited here.

[0059] In one embodiment, the second screening device 2200 may include a second impurity cleaner and a second vibrating screen, the input end of the second impurity cleaner is used to receive the second raw material, the output end of the second impurity cleaner is connected to the input end of the second vibrating screen, and the output end of the second vibrating screen is connected to the input end of the second quantitative feeding device 2300. In this process, the second raw material (antioxidant) can first pass through the second impurity cleaner, and the second impurity cleaner is used to clean the metal and dust impurities doped in the antioxidant, and mainly further remove the hardened antioxidant and impurities that may exist in the antioxidant.

[0060] The design reason for using the second impurity cleaner and the second vibrating screen to treat the antioxidant is: in the process of producing cross-linked polyethylene, melt extrusion is one of the key processes for preparing XLPE insulating materials. In the actual production process, due to changes in factors such as raw materials and process parameters, the stability of the melt extrusion process is affected, which in turn affects the quality and performance of the product. Among them, this field focuses more on the treatment and screening of base materials, but after research, it is found that in the process of producing cross-linked polyethylene, the added part of the antioxidant is more likely to have hardened antioxidants and impurities, which will affect the quality and performance of the product. This part of the problem has not been discovered or ignored, and has always affected the stability of the melt extrusion process.

[0061] Therefore, in the melt extrusion system of the present application, a second impurity cleaner and a second vibrating screen are added to the melt extrusion system to solve the problems found, and the agglomerated antioxidants and impurities in the antioxidants are removed in a targeted manner, thereby ensuring the stability of the melt extrusion process. The antioxidants after impurity cleaning are then screened for particle size by the second vibrating screen, and the particle size of the antioxidants is normalized to remove samples whose particle size does not meet the requirements.

[0062] At this time, the base material and antioxidant obtained after processing by the first feeding unit 1000 and the second feeding unit 2000 are then transported to the raw material extrusion unit 3000 for mixed extrusion processing and subsequent other processing processes. The influence of the solidified antioxidant and impurities on the stability of the melt extrusion process and the quality and performance of the product can be eliminated, thereby improving the stability of the melt extrusion process.

[0063] Continue reading Figure 1As shown, the input end of the raw material extrusion unit 3000 is connected to the output end of the first quantitative feeding device 1300 and the output end of the second quantitative feeding device 2300, and is used to quantitatively receive the first raw material and the second raw material that have been screened, that is, to weigh the preferred base material and the antioxidant according to a certain ratio, and simultaneously enter the raw material extrusion unit 3000. Among them, the first quantitative feeding device 1300 and the second quantitative feeding device 2300 can adopt a loss-in-weight scale. In one embodiment, the raw material extrusion unit 3000 includes a screw extruder 3100, the input end of the screw extruder 3100 is connected to the output end of the first quantitative feeding device 1300 and the output end of the second quantitative feeding device 2300, and the output end of the screw extruder 3100 is used to connect the input end of the pelletizing unit 4000.

[0064] The screw extruder 3100 is provided with a screw drive motor 3200, a melt pump 3300 and a screen changer 3400. The melting temperature range of the melt pump 3300 can be controlled to be between 170°C and 190°C, the current of the screw drive motor 3200 is ensured to be between 300A-340A, and the speed is between 10rpm and 30rpm. At the same time, the pressure in front of the screen changer 3400 filter during the extrusion process is recorded in real time, and the time for replacing the filter of the screen changer 3400 can be set between 12h and 48h.

[0065] During the production process, the base material and the antioxidant are easily separated when they are mixed in proportion and enter the raw material extrusion unit 3000. The separation of the two will affect the quality and performance of the product. Therefore, in one embodiment, the melt extrusion system is further provided with a blending and stirring device 3500. Figure 1 As shown, the input end of the blending and stirring device 3500 is connected to the output end of the first quantitative feeding device 1300 and the output end of the second quantitative feeding device 2300, and the output end of the blending and stirring device 3500 is connected to the input end of the raw material extrusion unit 3000, and the input end of the raw material extrusion unit 3000 is indirectly connected to the output end of the first quantitative feeding device 1300 and the output end of the second quantitative feeding device 2300 through the blending and stirring device 3500.

[0066] After adding the blending and stirring device 3500, when the preferred base material and antioxidant are weighed respectively according to a certain proportion, they can first enter the blending and stirring device 3500 for sufficient and uniform mixing. After the base material and antioxidant are evenly mixed, they are transported to the raw material extrusion unit 3000. This can solve the problem of the base material and antioxidant being easily separated when entering the raw material extrusion unit 3000, thereby ensuring the stability of the melt extrusion process, as well as the quality and performance of the product.

[0067] Continue reading Figure 2As shown, in one embodiment, the melt extrusion system includes a pelletizing unit 4000 and a dehydration unit 5000, the input end of the pelletizing unit 4000 is connected to the output end of the raw material extrusion unit 3000, and the input end of the dehydration unit 5000 is connected to the output end of the pelletizing unit 4000. The extruded sample of the base material and the antioxidant obtained by the raw material extrusion unit 3000 can be obtained by underwater pelletizing to obtain a semi-finished insulating material, and then the semi-finished insulating material is pressurized and sent to the dehydration unit 5000 through a closed circulating water flow path for dehydration treatment.

[0068] In one embodiment, the pelletizing unit 4000 includes an underwater pelletizing device 4100, a fluid delivery pipeline 4200, a fluid delivery pump body 4300, a pure water filter 4400, and a conductivity testing device 4500. The input end of the underwater pelletizing device 4100 is connected to the output end of the raw material extrusion unit 3000, and the output end of the underwater pelletizing device 4100 is connected to the input end of the dehydration unit 5000. Both the underwater pelletizing device 4100 and the dehydration unit 5000 are provided with a reflux end.

[0069] The fluid delivery pipeline 4200 includes a first pipeline section 4201 and a second pipeline section 4202. The first pipeline section 4201 connects the output end of the underwater pelletizing device 4100 and the input end of the dehydration unit 5000, and the second pipeline section 4202 connects the return end of the dehydration unit 5000 and the return end of the underwater pelletizing device 4100. Figure 2 As shown, the first pipeline section 4201 and the second pipeline section 4202 can form a closed circulating water flow path between the underwater pelletizing device 4100 and the dehydration unit 5000 after being connected.

[0070] Continue reading Figure 2 As shown, the fluid delivery pump body 4300 is arranged in the second pipeline section 4202, the fluid delivery pump body 4300 is the driving power source of the pure water in the fluid delivery pipeline 4200, the pure water filter device 4400 is arranged in the second pipeline section 4202, and the pure water filter device 4400 is located between the underwater pelletizing device 4100 and the fluid delivery pump body 4300. Since the purity of pure water will affect the quality and performance of the product, the pure water filter device 4400 can be used to filter the pure water to ensure the purity of the pure water. However, the pure water filter device 4400 has problems such as malfunction and aging. When the pure water filter device 4400 cannot ensure the effective filtration of pure water and cannot meet the purity requirements, it will still affect the quality and performance of the product.

[0071] Therefore, in one embodiment, the conductivity testing device 4500 can be disposed in the fluid delivery pipeline 4200. The conductivity testing device 4500 can detect the conductivity data of the pure water in the fluid delivery pipeline 4200 in real time, and the purity of the pure water can be determined based on the conductivity data, thereby ensuring that the purity of the circulating pure water meets the process requirements, thereby ensuring the stability of the melt extrusion process, and the quality and performance of the product.

[0072] In one embodiment, the fluid delivery pipeline 4200 is set to have a first position, a second position and a third position, wherein the first position is located at the first pipeline section 4201, the second position and the third position are located at the second pipeline section 4202, and the second position is located between the underwater pelletizing device 4100 and the pure water filtration device 4400, and the third position is located between the fluid delivery pump body 4300 and the dehydration unit 5000, and at least one of the first position, the second position and the third position is provided with at least one conductivity testing device 4500.

[0073] Among them, the conductivity test device 4500 is set at the first position to detect the conductivity data of the used pure water just after the underwater pelletizing operation is completed. The conductivity test device 4500 is set at the second position to detect the conductivity data of the pure water before the pure water is used for the underwater pelletizing operation. The conductivity test device 4500 is set at the third position to detect the conductivity data of the pure water after centrifugal drying and filtration. In the above design, the purity of the circulating pure water can be guaranteed by detecting the conductivity data of the pure water at different positions.

[0074] Continue reading Figure 3 As shown, in one embodiment, the melt extrusion system includes a third screening device 6100 and a heat preservation storage device 6200. The input end of the third screening device 6100 is connected to the output end of the dehydration unit 5000, and the input end of the heat preservation storage device 6200 is connected to the output end of the third screening device 6100. Therefore, after the semi-finished insulating material undergoes underwater pelletizing and dehydration, it can also be screened by the third screening device 6100 (such as a vibrating screen) to screen out abnormal pelletizing particles, and dried in the heat preservation storage device 6200 (such as a storage tank) at 60°C to 80°C.

[0075] Continue reading Figure 4As shown, in one embodiment, the melt extrusion system includes a third feeding unit 6300, and the third feeding unit 6300 includes a third storage device 6310 and a third quantitative feeding device 6320. The third storage device 6310 is used to store the third raw material, and the output end of the third storage device 6310 is connected to the input end of the third quantitative feeding device 6320. The third raw material can be selected as a cross-linking agent, which is stored in the third storage device 6310. When the semi-finished insulating material is dried by the heat preservation storage device 6200, it can be mixed with the cross-linking agent. Figure 5 As shown, in one embodiment, the melt extrusion system includes a shaking pot device 6400, a heat preservation device 6500 and a cooling device 6600. The input end of the shaking pot device 6400 is connected to the output end of the heat preservation storage device 6200 and the output end of the third quantitative feeding device 6320, the input end of the heat preservation device 6500 is connected to the output end of the shaking pot device 6400, and the input end of the cooling device 6600 is connected to the output end of the heat preservation device 6500.

[0076] Therefore, in one embodiment, after the semi-finished insulating material is dried by the heat preservation storage device 6200, it can enter the shaking tank device 6400 together with the cross-linking agent at 60°C to 80°C. At this time, the rotation speed of the shaking tank device 6400 can be controlled between 20rpm and 50rpm, and the temperature can be controlled between 60°C and 80°C to ensure that the surface of the granules obtained by mixing the semi-finished insulating material and the cross-linking agent is dry. After that, it can fall vertically into the heat preservation device 6500 (for example, the post-absorption heat preservation bin) for heat preservation, infiltration, diffusion, and post-absorption. The heat preservation temperature is controlled between 50°C and 80°C, and the heat preservation time is between 12h and 24h. After the post-absorption is complete, the ultra-clean chemical cross-linked polyethylene insulation material for ultra-high voltage cables is obtained. After cooling by the cooling device 6600, and the impurities are separated and collected, the high-voltage cross-linked polyethylene that is completely packed and stable in batches can be obtained.

[0077] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A melt extrusion system, characterized in that: The melt extrusion system comprises: A first feeding unit, the first feeding unit comprising a first screening device and a first quantitative feeding device, the first screening device is used to receive and screen the first raw material according to the first screening standard, the output end of the first screening device is connected to the input end of the first quantitative feeding device, and is used to transport the screened first raw material to the first quantitative feeding device; A second feeding unit, the second feeding unit comprising a second screening device and a second quantitative feeding device, the second screening device is used to receive and screen the second raw material according to the second screening standard, the output end of the second screening device is connected to the input end of the second quantitative feeding device, and is used to transport the screened second raw material to the second quantitative feeding device; A raw material extrusion unit, the input end of which is connected to the output end of the first quantitative feeding device and the output end of the second quantitative feeding device, and is used for quantitatively receiving the screened first raw material and the second raw material.

2. The melt extrusion system according to claim 1, characterized in that: The melt extrusion system comprises: A pelletizing unit, wherein the input end of the pelletizing unit is connected to the output end of the raw material extrusion unit; A dehydration unit, wherein the input end of the dehydration unit is connected to the output end of the pelletizing unit.

3. The melt extrusion system according to claim 2, characterized in that: The pelletizing unit comprises: An underwater pelletizing device, wherein the input end of the underwater pelletizing device is connected to the output end of the raw material extrusion unit, the output end of the underwater pelletizing device is connected to the input end of the dehydration unit, and the underwater pelletizing device and the dehydration unit are both provided with a reflux end; A fluid delivery pipeline, the fluid delivery pipeline comprising a first pipeline section and a second pipeline section, the first pipeline section connecting the output end of the underwater pelletizing device and the input end of the dehydration unit, and the second pipeline section connecting the return end of the dehydration unit and the return end of the underwater pelletizing device; A fluid delivery pump body, wherein the fluid delivery pump body is arranged in the second pipeline section; A pure water filter device, which is arranged in the second pipeline section and located between the underwater pelletizing device and the fluid delivery pump body; A conductivity testing device is provided in the fluid delivery pipeline.

4. The melt extrusion system according to claim 3, characterized in that: The fluid delivery pipeline is set to have a first position, a second position and a third position, wherein the first position is located in the first pipeline section, the second position and the third position are located in the second pipeline section, and the second position is located between the underwater pelletizing device and the pure water filtration device, and the third position is located between the fluid delivery pump body and the dehydration unit, and at least one of the first position, the second position and the third position is provided with at least one conductivity testing device.

5. The melt extrusion system according to claim 2, characterized in that: The melt extrusion system comprises: a third screening device, wherein an input end of the third screening device is connected to an output end of the dehydration unit; A heat-insulating material storage device, wherein the input end of the heat-insulating material storage device is connected to the output end of the third screening device.

6. The melt extrusion system according to claim 5, characterized in that: The melt extrusion system comprises: The third feeding unit comprises a third storage device and a third quantitative feeding device. The third storage device is used to store a third raw material. The output end of the third storage device is connected to the input end of the third quantitative feeding device.

7. The melt extrusion system according to claim 6, characterized in that: The melt extrusion system comprises: A shaking can device, wherein the input end of the shaking can device is connected to the output end of the heat-insulating material storage device and the output end of the third quantitative feeding device.

8. The melt extrusion system according to claim 7, characterized in that: The melt extrusion system comprises: A heat preservation device, wherein the input end of the heat preservation device is connected to the output end of the shaking pot device.

9. The melt extrusion system according to claim 8, characterized in that: The melt extrusion system comprises: A cooling device, wherein the input end of the cooling device is connected to the output end of the heat preservation device.

10. The melt extrusion system according to claim 1, characterized in that: The melt extrusion system further comprises a blending and stirring device, the input end of the blending and stirring device is connected to the output end of the first quantitative feeding device and the output end of the second quantitative feeding device, the output end of the blending and stirring device is connected to the input end of the raw material extrusion unit, and the input end of the raw material extrusion unit is indirectly connected to the output end of the first quantitative feeding device and the output end of the second quantitative feeding device through the blending and stirring device; and / or, The first feeding unit further comprises a first storage device, the first storage device is used to store the first raw material, the output end of the first storage device is connected to the input end of the first screening device; and / or, The second feeding unit further comprises a second storage device, the second storage device is used to store the second raw material, the output end of the second storage device is connected to the input end of the second screening device; and / or, The first screening device comprises a first impurity cleaner and a first vibrating screen, wherein the input end of the first impurity cleaner is used to receive the first raw material, the output end of the first impurity cleaner is connected to the input end of the first vibrating screen, and the output end of the first vibrating screen is connected to the input end of the first quantitative feeding device; and / or, The second screening device comprises a second impurity cleaner and a second vibrating screen, the input end of the second impurity cleaner is used to receive the second raw material, the output end of the second impurity cleaner is connected to the input end of the second vibrating screen, and the output end of the second vibrating screen is connected to the input end of the second quantitative feeding device; and / or, The raw material extrusion unit includes a screw extruder, the input end of the screw extruder is connected to the output end of the first quantitative feeding device and the output end of the second quantitative feeding device, and the output end of the screw extruder is used to connect to the input end of the pelletizing unit, wherein the screw extruder is provided with a screw drive motor, a melt pump and a screen changer.

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