A cooling system for melt spinning

Abstract

The utility model discloses a cooling system of melt spinning, including spinning beam, cooling cylinder section, first heating assembly, second heating unit and recovery spare, first heating assembly output trace heat nitrogen, both realized the protection of anti -oxidation of melt stream, avoided the oxidation risk that traditional cooling medium direct contact possibly brought again, cooperate the temperature regulation of second heating unit to cooling cylinder section simultaneously, realize the accurate control of whole process temperature from the anti -oxidation to high -temperature natural cooling, high -temperature natural cooling and do not send the work process of cold -wind, combine gradient type process temperature control, can initiative lengthen the solidification orientation length of melt stream and process, differ from the defect that the orientation is insufficient in the prior art that cools too fast, provide the key condition for the optimization of fiber orientation structure, coaxially stacked cooling cylinder section and nitrogen recovery operation, both constructed the stable cooling environment, avoid the fiber shaking again, improved nitrogen utilization rate and environmental safety, balanced the process stability and economy.

Description

Technical Field

[0001] This application relates to the field of synthetic fiber production technology, and in particular to a cooling system for melt spinning. Background Technology

[0002] In melt spinning, the cooling process is a crucial link between melt extrusion and subsequent processing, directly determining the solidification quality of the filaments and the performance of the final product. Its technical rationality and stability are vital to the entire spinning process. However, existing melt spinning cooling technologies still have multiple shortcomings in practical applications. For high-melting-point specialty raw materials, current technologies fail to create a temperature field that matches the requirements of the spinning process. This results in the flow field being unable to adjust synchronously to maintain heat transfer stability when the cooling medium temperature fluctuates. When local turbulence occurs in the flow field, it can easily trigger rapid crystallization and cooling of the fibers, ultimately leading to uneven filament solidification quality. This creates potential quality risks for subsequent processes such as drawing and heat treatment, failing to guarantee the excellent intrinsic quality of the newly formed fibers.

[0003] Existing cooling air blowing devices only focus on the basic function of "achieving cooling" by supplying air, without addressing the dynamic needs of special raw material spinning processes. Special raw materials (such as liquid crystal polyarylate) do not require cooling by supplying cold air. Ensuring the stability of the flow field and the medium to control fiber disturbances can achieve continuous and high-quality fiber production. Utility Model Content

[0004] In view of the deficiencies in the prior art, this application provides a cooling system for melt spinning to solve the problems of low reliability and low stability of the cooling system in the prior art.

[0005] The above-mentioned objectives of this application are mainly achieved through the following technical solutions: A cooling system for melt spinning, the cooling system comprising: The spinning box has an internal working space for holding molten material. The spinning box is equipped with a component spinneret, through which the molten material forms a fine stream of molten material. A cooling cylinder section is connected to the lower part of the spinning box. Multiple cooling cylinder sections are provided, and each section has an internal channel. The cooling cylinder sections are coaxially stacked and arranged below the spinneret of the assembly. The first heating component is connected between the spinneret and the cooling cylinder section and is used to output nitrogen gas at the target temperature. The second heating unit is provided in multiple units and is respectively connected to the outer wall of the multiple cooling cylinder sections, and can exchange heat with the cooling cylinder sections; The recovery unit is connected to the cooling cylinder section that is remote from the spinning box and is used to collect nitrogen gas output from the first heating assembly.

[0006] In an optional embodiment, a heat insulation section is provided between adjacent cooling cylinder sections.

[0007] In an optional embodiment, the first heating component includes a heater, a heat exchanger, and a nitrogen delivery component. The heater can heat the medium inside the heat exchanger, and the nitrogen delivery component is connected to the heat exchanger so that the nitrogen inside the nitrogen delivery component can exchange heat with the medium.

[0008] In an optional embodiment, the end of the first heating component is provided with an air outlet, which is arranged in a porous annular shape.

[0009] In an optional embodiment, the second heating unit is an electromagnetic heating coil, and the second heating unit is connected to an electromagnetic heating controller.

[0010] In an optional embodiment, the electromagnetic heating controller controls the temperature of a plurality of second heating units to decrease sequentially from the spinning box toward the recycling component.

[0011] In an optional embodiment, the recovery component includes a porous cylindrical component and a negative pressure fan connected to the porous cylindrical component. The porous cylindrical component is arranged within the cooling cylinder section, and the negative pressure fan is connected to the porous cylindrical component via a recovery pipe.

[0012] In an optional embodiment, the spinning box is equipped with a metering pump.

[0013] In an optional embodiment, the cooling cylinder section is provided with at least two sets.

[0014] In an optional embodiment, the cooling system further includes a lifting assembly connected to the spinning box and capable of driving the spinning box to move up or down.

[0015] Compared with the prior art, the advantages of this application are: The cooling system described in this application is used for cooling operations in melt spinning. The cooling system includes a spinning box, cooling cylinder sections, a first heating assembly, a second heating unit, and a recovery unit. The spinning box has an internal working space for accommodating molten material. An assembly spinneret is located inside the spinning box, through which the molten material forms a fine melt stream. Multiple cooling cylinder sections are connected to the lower part of the spinning box and have internal channels. The cooling cylinder sections are coaxially stacked and arranged below the assembly spinneret. The first heating assembly is connected between the assembly spinneret and the cooling cylinder sections and is used to output nitrogen gas at the target temperature. Multiple second heating units are provided and connected to the outer walls of multiple cooling cylinder sections, respectively, and can exchange heat with the cooling cylinder sections. The recovery unit is connected to a connected cooling cylinder section away from the spinning box and is used to collect the nitrogen gas output by the first heating assembly.

[0016] After the molten material in the spinning box is formed into a molten stream by the spinneret, the first heating element connected between the spinneret and the cooling cylinders outputs heated nitrogen gas at the target temperature. This heated nitrogen gas not only provides precise anti-oxidation protection for the freshly extruded molten stream, preventing oxidation reactions from contact with air and affecting fiber quality, but also maintains a suitable initial state for the molten stream before entering the cooling stage by controlling the temperature of the heated nitrogen gas. Subsequently, the molten stream enters multiple coaxially stacked cooling cylinders below. The cooling cylinders employ high-temperature natural cooling, and the process temperature of each cooling cylinder is precisely controlled through the heat exchange of the second heating unit on the outer wall of the cooling cylinder, creating a gradient high-temperature cooling environment within the cooling cylinders. This effectively lengthens the solidification orientation length and solidification process of the molten stream, allowing the molecular chains inside the molten stream more time to arrange themselves in an orderly manner, thereby optimizing the fiber orientation structure.

[0017] The coaxially stacked cooling cylinders can create a closed and stable cooling space around the melt stream, avoiding flow field disturbances caused by external airflow interference and eliminating fiber vibration caused by local airflow disturbances. The nitrogen flowing through the cooling cylinders is collected by the recovery unit, which can reduce nitrogen waste or pollution on the one hand, and maintain a stable pressure in the flow field within the cooling cylinders on the other hand, further ensuring the continuity and stability of the cooling process.

[0018] This cooling system outputs a small amount of hot nitrogen through the first heating component, which not only protects the melt stream from oxidation but also avoids the oxidation risks that may arise from direct contact with traditional cooling media. Simultaneously, the second heating unit regulates the temperature of the cooling cylinder section, achieving precise temperature control throughout the entire process, from oxidation prevention to high-temperature natural cooling. This solves the problems of existing temperature fields being unable to dynamically adapt to process requirements and the fiber disturbance easily caused by cold air. The high-temperature natural cooling process without cold air supply, combined with gradient process temperature control, actively lengthens the solidification and orientation length of the melt stream, unlike existing technologies where excessively rapid cooling leads to insufficient orientation. This provides crucial conditions for optimizing fiber orientation structure. The coaxially stacked cooling cylinder section and nitrogen recovery operation create a stable cooling environment, preventing fiber vibration and improving nitrogen utilization, thus balancing process stability and economy.

[0019] The synergistic effect of hot nitrogen's anti-oxidation protection and high-temperature natural cooling ensures that the melt stream is free from oxidation risk and releases heat steadily during cooling, avoiding filament quality problems caused by oxidation or sudden temperature changes. At the same time, the elongated solidification orientation length and process can significantly optimize fiber orientation and greatly improve the strength of the final fiber. The absence of cold air and the enclosed cooling space solve the fiber vibration problem caused by flow field turbulence in existing technologies, reducing the probability of filament breakage in subsequent drawing processes and reducing product quality fluctuations after setting. Through the flexible control of process temperature by the second heating unit, the entire system can adapt to the process requirements of different spinning speeds and polymer types, providing reliable support for the large-scale production of high-speed, high-quality liquid crystal polyarylate fibers. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A schematic diagram of the cooling system provided in the embodiments of this application; In the diagram: 100, spinning box; 101, spinneret; 102, metering pump; 200, cooling section; 201, heat insulation section; 300, first heating assembly; 301, heater; 302, heat exchanger; 303, nitrogen delivery assembly; 304, gas outlet; 401, second heating unit; 402, electromagnetic heating controller; 501, perforated cylinder; 502, negative pressure fan; 601, lifting assembly. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that the description of these embodiments is intended to aid in understanding the present invention, but does not constitute a limitation thereof. The specific structural and functional details disclosed herein are only for describing exemplary embodiments of the present invention. However, the present invention may be embodied in many alternative forms and should not be construed as being limited to the embodiments described herein.

[0023] like Figure 1 As shown, Figure 1 This is a schematic diagram of a cooling system provided in an embodiment of this application; a cooling system for melt spinning, the cooling system including a spinning box 100, a cooling cylinder section 200, a first heating component 300, a second heating unit 401, and a recovery component, wherein: like Figure 1As shown, the spinning box 100 has an internal working space for accommodating molten material, and the spinning box 100 has an internal spinneret 101, through which the molten material forms a fine stream of molten material; The spinning box 100 serves as the initial unit for melt containment and extrusion. The spinning box 100 has a sealed working space inside, and the outer wall of the working space can be equipped with a heat insulation layer to maintain the melt material within the preset process temperature range and prevent the melt from having abnormal viscosity due to temperature fluctuations. The component spinneret 101 can be made of high-temperature resistant alloy material. Multiple spinnerets are evenly distributed on the component spinneret 101. The melt material is evenly extruded through the spinnerets to form a melt stream with a uniform diameter. The spinneret and the central axis of the cooling cylinder section 200 below are kept coincident to ensure that the melt stream can enter the cooling area vertically.

[0024] like Figure 1 As shown, a cooling cylinder section 200 is connected to the lower part of the spinning box 100. Multiple cooling cylinder sections 200 are provided, and channels are provided inside. The cooling cylinder sections 200 are coaxially stacked and arranged below the spinneret 101 of the assembly.

[0025] The number of cooling cylinder sections 200 can be flexibly set according to the spinning speed and cooling requirements. Each cooling cylinder section 200 has an annular channel inside for the melt stream to pass through and for nitrogen to flow, which can guide the nitrogen to flow smoothly along the cylinder section axis and avoid local airflow eddies. The cooling cylinder sections 200 are coaxially stacked, and sealing gaskets are provided at the connection of adjacent cylinder sections, which not only ensures the airtightness of the cooling space, but also facilitates the disassembly and adjustment of the number of cylinder sections according to process requirements. In addition, the central axis of the entire cooling cylinder section 200 group is completely coincident with the central axis of the spinneret 101 of the component, ensuring that the melt stream is always in the center of the cooling area and avoiding uneven cooling caused by offset.

[0026] like Figure 1 As shown, the first heating component 300 is connected between the spinneret 101 and the cooling cylinder section 200, and is used to output nitrogen gas at the target temperature. As a key unit for oxidation prevention and initial temperature stabilization, the first heating component 300 heats the nitrogen gas to the target temperature and outputs hot nitrogen gas around the melt stream. This forms a dense nitrogen protective layer on the surface of the melt stream, isolating it from air to prevent the oxidative degradation of the liquid crystal polyarylate. Furthermore, by regulating the temperature of the hot nitrogen gas, the freshly extruded melt stream maintains a suitable initial temperature, avoiding excessively rapid surface solidification due to a sudden temperature drop. In addition, the first heating component 300 can dynamically adjust the nitrogen temperature and flow rate according to the diameter and spinning speed of the melt stream to balance the heat release rate of the melt stream.

[0027] like Figure 1As shown, there are multiple second heating units 401, which are respectively connected to the outer walls of the multiple cooling cylinder sections 200 and can exchange heat with the cooling cylinder sections 200.

[0028] The number of second heating units 401 is the same as the number of cooling cylinder sections 200. Each second heating unit 401 is wrapped around the outer wall of the corresponding cooling cylinder section 200. The temperature environment of each cooling cylinder section 200 area is controlled by heat exchange, thereby optimizing the orientation structure of the fiber. At the same time, the second heating unit 401 can also adjust the temperature gradient according to the specific model of liquid crystal polyarylate and liquid crystal polyarylate with different molecular weights to adapt to its higher solidification temperature requirements.

[0029] The recovery unit is connected to the cooling cylinder section 200, which is located away from the spinning box 100, and is used to collect the nitrogen gas output by the first heating component 300. As an auxiliary unit for nitrogen gas circulation and flow field stabilization, the recovery unit can reduce nitrogen gas consumption costs and maintain a slight positive pressure in the channel within the cooling cylinder section 200, ensuring that nitrogen gas flows smoothly in one direction along the channel and avoiding flow field turbulence caused by pressure fluctuations.

[0030] like Figure 1 As shown, in an optional embodiment, the cooling system of this application is used for cooling operations during melt spinning. The cooling system includes a spinning box 100, a cooling cylinder section 200, a first heating component 300, a second heating unit 401, and a recovery component. The spinning box 100 has an internal working space for accommodating molten material, and an assembly spinneret 101 is provided inside the spinning box 100. The molten material forms a fine melt stream through the assembly spinneret 101. The cooling cylinder section 200 is connected to the lower part of the spinning box 100, and multiple cooling cylinder sections 200 are provided, each with internal channels. The cooling cylinder sections 200 are coaxially stacked and arranged at the lower part of the spinneret 101 of the assembly; the first heating assembly 300 is connected between the spinneret 101 of the assembly and the cooling cylinder sections 200, and is used to output nitrogen gas at the target temperature; multiple second heating units 401 are provided and are respectively connected to the outer walls of multiple cooling cylinder sections 200, and can exchange heat with the cooling cylinder sections 200; the recovery unit is connected to the cooling cylinder section 200 that is far away from the spinning box 100, and is used to collect the nitrogen gas output by the first heating assembly 300.

[0031] After the molten material in the spinning box 100 is formed into a molten stream by the spinneret 101, the first heating component 300, connected between the spinneret 101 and the cooling cylinder section 200, outputs heated nitrogen gas at the target temperature. This heated nitrogen gas not only provides precise anti-oxidation protection for the freshly extruded molten stream, preventing oxidation reactions that could affect fiber quality, but also maintains a suitable initial state for the molten stream before entering the cooling stage by controlling the temperature of the heated nitrogen gas. Subsequently, the molten stream enters multiple coaxially stacked cooling cylinder sections 200 below. The cooling cylinder sections 200 employ a high-temperature natural cooling method. Through the heat exchange effect of the second heating unit 401 on the outer wall of the cooling cylinder section 200, the process temperature of each cooling cylinder section 200 is precisely controlled, creating a gradient high-temperature cooling environment within the cooling cylinder section 200. This effectively lengthens the solidification orientation length and solidification process of the molten stream, allowing the molecular chains inside the molten stream more time to arrange themselves in an orderly manner, thereby optimizing the fiber orientation structure.

[0032] The coaxially stacked cooling cylinder sections 200 can construct a closed and stable cooling space around the melt stream, avoiding flow field disturbances caused by external airflow interference and eliminating fiber vibration caused by local airflow disturbances. The nitrogen flowing through the cooling cylinder section 200 is collected by the recovery unit, which can reduce nitrogen waste or pollution on the one hand, and maintain a stable pressure in the flow field inside the cooling cylinder section 200 on the other hand, further ensuring the continuity and stability of the cooling process.

[0033] This cooling system outputs a small amount of hot nitrogen through the first heating component 300, which not only protects the melt stream from oxidation but also avoids the oxidation risks that may arise from direct contact with traditional cooling media. Simultaneously, in conjunction with the second heating unit 401, it regulates the temperature of the cooling cylinder section 200, achieving precise temperature control throughout the entire process from oxidation prevention to high-temperature natural cooling. This solves the problems of existing temperature fields being unable to dynamically adapt to process requirements and being prone to fiber disturbance due to cold air. The high-temperature natural cooling process without cold air supply, combined with gradient process temperature control, actively lengthens the solidification and orientation length of the melt stream, unlike existing technologies where excessively rapid cooling leads to insufficient orientation, providing key conditions for optimizing fiber orientation structure. The coaxially stacked cooling cylinder section 200 and nitrogen recovery operation create a stable cooling environment, preventing fiber vibration and improving nitrogen utilization, thus balancing process stability and economy.

[0034] The synergistic effect of hot nitrogen's anti-oxidation protection and high-temperature natural cooling ensures that the melt stream is free from oxidation risk and releases heat steadily during cooling, avoiding filament quality problems caused by oxidation or sudden temperature changes. At the same time, the elongated solidification orientation length and process can significantly optimize fiber orientation and greatly improve the strength of the final fiber. The absence of cold air and the enclosed cooling space solve the fiber vibration problem caused by flow field turbulence in existing technologies, reducing the probability of filament breakage in subsequent drawing processes and reducing product quality fluctuations after setting. Through the flexible control of process temperature by the second heating unit 401, the entire system can adapt to the process requirements of different spinning speeds and polymer types, providing reliable support for the large-scale production of high-speed, high-quality liquid crystal polyarylate fibers.

[0035] like Figure 1 As shown, in an optional embodiment, a heat insulation section 201 is provided between adjacent cooling cylinder sections 200. The heat insulation section 201 can be made of ceramic fiber or aerogel material, with a thickness of 5-10 mm. The inner diameter of the heat insulation section 201 is consistent with the inner diameter of the cooling cylinder section 200 to avoid obstructing the flow of nitrogen and the fine flow of melt. In the prior art, adjacent cooling cylinder sections 200 often interfere with each other due to heat conduction, making it impossible to form a precise gradient temperature field. However, this embodiment blocks the heat transfer between adjacent cylinder sections by using the heat insulation section 201, ensuring that the temperature of each cooling cylinder section 200 is independently controlled by the corresponding second heating unit 401, further improving the accuracy of the gradient temperature distribution. Especially for materials such as liquid crystal polyarylate that are sensitive to temperature gradients, it can more accurately control the solidification orientation process and avoid the problem of uneven fiber orientation caused by temperature crosstalk. At the same time, the flexible material design of the heat insulation section 201 also facilitates the disassembly and assembly of the cooling cylinder section 200, improving the convenience of equipment maintenance.

[0036] like Figure 1 As shown, in an optional embodiment, the first heating component 300 includes a heater 301, a heat exchanger 302, and a nitrogen delivery component 303. The heater 301 can heat the medium in the heat exchanger 302, and the nitrogen delivery component 303 is connected to the heat exchanger 302 so that the nitrogen in the nitrogen delivery component 303 can exchange heat with the medium.

[0037] The first heating assembly 300 includes a heater 301, a heat exchanger 302, and a nitrogen delivery assembly 303. The heater 301 can be an electric heating tube, the heat exchanger 302 is a stainless steel spiral tube, and the interior can be filled with heat-conducting oil as the heat exchange medium. The nitrogen delivery assembly 303 includes a nitrogen pump and a delivery pipe, which is wound around the outer wall of the spiral tube of the heat exchanger 302 and tightly fitted. Through the indirect heat exchange path of "heater 301, heat exchange medium, and nitrogen", the high specific heat capacity of the heat-conducting oil is used to achieve uniform heat transfer, reducing the temperature fluctuation range of nitrogen. At the same time, the heat exchanger 302 extends the contact time between nitrogen and the heat exchange medium, ensuring that the nitrogen is fully heated to the target temperature; effectively avoiding the uneven heating and temperature fluctuations caused by direct nitrogen heating.

[0038] The power of heater 301 can be adjusted in conjunction with the nitrogen flow rate via the temperature control module. In high-speed spinning scenarios, when the nitrogen flow rate increases, the power of heater 301 increases synchronously to avoid a drop in nitrogen temperature due to flow rate changes. This further ensures the stability of anti-oxidation protection and initial temperature stabilization, and provides more reliable temperature adaptability for cooling requirements under different spinning process parameters.

[0039] like Figure 1 As shown, in an optional embodiment, the end of the first heating component 300 is provided with an outlet 304, which is arranged in a porous annular shape. In the prior art, uneven distribution of nitrogen gas often leads to a lack of protection in some areas of the melt stream. However, the porous annular outlet 304 of this embodiment can form a uniform nitrogen protective layer around the melt stream, preventing air from entering through local gaps and causing oxidation. While forming the protective layer, the nitrogen can also provide a guiding airflow along the axial direction of the cooling cylinder section 200, assisting the nitrogen to flow towards the recovery component, reducing nitrogen retention at the top of the cooling cylinder section 200, avoiding flow field turbulence caused by nitrogen accumulation, and further improving flow field stability. Especially for the spinneret 101 of the component with multiple spinnerets, it can ensure that each melt stream receives uniform anti-oxidation protection and airflow guidance.

[0040] like Figure 1 As shown, in an optional embodiment, the second heating unit 401 is an electromagnetic heating coil, and the second heating unit 401 is connected to an electromagnetic heating controller 402.

[0041] The electromagnetic heating coil can be made of copper wire and tightly fitted onto the outer wall of the cooling cylinder section 200. The electromagnetic heating controller 402 can achieve precise temperature control within a preset range. The electromagnetic heating coil heats the cooling cylinder section 200 itself through electromagnetic induction, improving heating efficiency and increasing the heating rate. It can quickly respond to temperature adjustment needs, especially when switching spinning process parameters, it can quickly adjust the temperature gradient of the cooling cylinder section 200, reducing process switching time. At the same time, the electromagnetic heating controller 402 supports multi-unit linkage control and can store temperature gradient parameters of different processes through preset programs to achieve one-click switching, improving production efficiency. In addition, the non-flame and non-contact characteristics of electromagnetic heating also reduce the safety risks of equipment operation, making it suitable for large-scale industrial production scenarios.

[0042] In an optional embodiment, the electromagnetic heating controller 402 controls the temperature of a plurality of second heating units 401 to decrease sequentially from the spinning box 100 toward the recycling component.

[0043] The electromagnetic heating controller 402 controls the temperature of multiple second heating units 401 to decrease sequentially. Specifically, the temperature reduction control can be achieved through a preset gradient algorithm. For example, when the cooling cylinder section 200 is set to 5 sections, the preset temperature gradient can be 350℃, 345℃, 340℃, 335℃, and 330℃, and the temperature difference between adjacent cylinder sections can be flexibly adjusted within the range of 5-20℃. Through the automatic gradient control function of the electromagnetic heating controller 402, gradient deviations caused by manual adjustment are avoided. At the same time, the electromagnetic heating controller 402 can optimize the temperature gradient according to the solidification state of the melt stream (through fiber strength data fed back by the subsequent detection unit). When the fiber strength is detected to be low, the temperature difference between adjacent cylinder sections is automatically reduced, prolonging the solidification orientation process and improving the orderliness of molecular chain arrangement. This further improves the convenience and accuracy of process control and provides technical support for the continuous optimization of the quality of liquid crystal polyarylate fibers.

[0044] like Figure 1 As shown, in an optional embodiment, the recovery component includes a porous cylindrical component 501 and a negative pressure fan 502 connected to the porous cylindrical component 501. The porous cylindrical component 501 is arranged inside the cooling cylinder section 200, and the negative pressure fan 502 is connected to the porous cylindrical component 501 through a recovery pipe.

[0045] The porous cylindrical component 501 is arranged inside the cooling cylinder section 200, with its central axis coinciding with that of the cooling cylinder section 200. A negative pressure fan 502 is connected to the bottom of the porous cylindrical component 501 via a recovery pipe to control the negative pressure value within the cooling cylinder section 200. In existing technologies, nitrogen recovery is mostly performed at the end of the cooling cylinder section 200, which can easily lead to uneven nitrogen flow within the section. In this embodiment, the porous cylindrical component 501 is built inside the cooling cylinder section 200. Through the uniform suction effect of the negative pressure fan 502, nitrogen forms a uniform radial flow field and a stable axial flow field within the cooling cylinder section 200. This avoids the shimmering of the melt stream caused by excessively fast or slow local airflow velocities and does not interfere with the melt stream. Furthermore, the power of the negative pressure fan 502 can be linked to the nitrogen flow rate for adjustment, ensuring a stable airflow state within the cooling cylinder section 200 at different spinning speeds, further improving flow field stability and nitrogen recovery efficiency.

[0046] like Figure 1 As shown, in an optional embodiment, a metering pump 102 is provided inside the spinning box 100. The metering pump 102 can be a gear metering pump 102, with the pump body made of high-temperature resistant alloy. It is sealed to the melt channel inside the spinning box 100. The rotation speed of the metering pump 102 can be adjusted within a preset range to control the extrusion flow rate of the melt. In the prior art, the melt extrusion flow rate mostly depends on the pressure control inside the spinning box 100, which has the problem of large flow fluctuations. The metering pump 102 can accurately control the extrusion amount of the melt per unit time, reducing the diameter deviation of the melt stream and avoiding uneven filament thickness caused by flow fluctuations. At the same time, the rotation speed of the metering pump 102 can be adjusted in conjunction with the subsequent drawing speed to achieve more reliable process parameter matching. When the drawing speed is increased, the rotation speed of the metering pump 102 increases synchronously to ensure the stability of the linear density of the melt stream. Especially for high-viscosity melts such as liquid crystal polyarylate, the precise feeding of the metering pump 102 can avoid the retention and degradation of the melt in the spinneret orifice, further improving the quality stability of the nascent fiber.

[0047] like Figure 1 As shown, in an optional embodiment, the cooling cylinder section 200 is provided with at least two sets. Multiple sets of cooling cylinder sections 200 are arranged symmetrically, enabling precise cooling of the melt streams on both sides for multi-nozzle spinning or wide-width spinning scenarios, ensuring all melt streams are in a stable cooling environment. Simultaneously, the multiple sets of cooling cylinder sections 200 can each have their temperature gradient set by an independent second heating controller to adapt to the cooling requirements of melt streams at different locations, further improving cooling uniformity. This provides equipment support for the production of wide-width, high-yield liquid crystal polyarylate fibers, broadening the application range of the cooling system.

[0048] like Figure 1As shown, in an optional embodiment, the cooling system further includes a lifting assembly 601, which is connected to the spinning box 100 and can drive the spinning box 100 to move up or down.

[0049] The lifting assembly 601 may include a servo motor, a ball screw, and a guide rail. The servo motor is connected to the ball screw through a reducer. The nut of the ball screw is fixedly connected to the bottom of the spinning box 100. The guide rail is slidably engaged with the side wall of the spinning box 100. The lifting assembly 601 can change the initial position of the melt stream entering the cooling cylinder section 200 by adjusting the height of the spinning box 100. When it is necessary to extend the solidification orientation length, the spinning box 100 is driven to rise, increasing the pre-cooling distance of the melt stream outside the cooling cylinder section 200. At the same time, it is also convenient to adjust the position of the spinning box 100 during equipment maintenance, improving maintenance convenience and further enhancing the process adaptability and operational flexibility of the cooling system.

[0050] It should be understood that the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. Although the terms "first," "second," etc., may be used herein to describe various units, these units should not be limited by these terms. These terms are only used to distinguish one unit from another. For example, a first unit may be referred to as a second unit, and similarly, a second unit may be referred to as a first unit, without departing from the scope of the exemplary embodiments of this utility model.

[0051] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" in this article describes another relationship between related objects, indicating that two relationships can exist. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the related objects before and after it are in an "or" relationship.

[0052] It should be understood that in the description of this utility model, the terms "upper," "vertical," "inner," "outer," etc., indicate the orientation or positional relationship when the disclosed product is used, or the orientation or positional relationship commonly understood by those skilled in the art. They 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. Therefore, they should not be construed as limitations on this utility model.

[0053] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" 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 direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0054] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” “containing,” and / or “including” as used herein specify the presence of the stated features, integers, steps, operations, units, and / or components, and do not exclude the presence or addition of one or more other features, quantities, steps, operations, units, components, and / or combinations thereof.

[0055] Specific details are provided in the following description to provide a complete understanding of the exemplary embodiments. However, those skilled in the art will understand that the exemplary embodiments can be implemented without these specific details. In other embodiments, well-known processes, structures, and techniques may be omitted in the depiction of non-essential details to avoid obscuring the exemplary embodiments.

[0056] The above are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

[0057] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art.

Claims

1. A cooling system for melt spinning, characterized in that, The cooling system includes: The spinning box has an internal working space for holding molten material. The spinning box is equipped with a component spinneret, through which the molten material forms a fine stream of molten material. A cooling cylinder section is connected to the lower part of the spinning box. Multiple cooling cylinder sections are provided, and each section has an internal channel. The cooling cylinder sections are coaxially stacked and arranged below the spinneret of the assembly. The first heating component is connected between the spinneret and the cooling cylinder section and is used to output nitrogen gas at the target temperature. The second heating unit is provided in multiple units and is respectively connected to the outer wall of the multiple cooling cylinder sections, and can exchange heat with the cooling cylinder sections; The recovery unit is connected to the cooling cylinder section that is remote from the spinning box and is used to collect nitrogen gas output from the first heating assembly.

2. The cooling system for melt spinning as described in claim 1, characterized in that: A heat insulation section is provided between adjacent cooling cylinder sections.

3. The cooling system for melt spinning as described in claim 1, characterized in that: The first heating component includes a heater, a heat exchanger, and a nitrogen delivery component. The heater can heat the medium inside the heat exchanger, and the nitrogen delivery component is connected to the heat exchanger so that the nitrogen in the nitrogen delivery component can exchange heat with the medium.

4. The cooling system for melt spinning as described in claim 3, characterized in that: The first heating component has an air outlet at its end, and the air outlet is arranged in a porous annular shape.

5. The cooling system for melt spinning as described in claim 1, characterized in that: The second heating unit is an electromagnetic heating coil, and the second heating unit is connected to an electromagnetic heating controller.

6. The cooling system for melt spinning as described in claim 5, characterized in that: From the spinning box toward the recycling component, the electromagnetic heating controller controls the temperature of multiple second heating units to decrease sequentially.

7. The cooling system for melt spinning as described in claim 1, characterized in that: The recovery component includes a porous cylindrical component and a negative pressure fan connected to the porous cylindrical component. The porous cylindrical component is arranged inside the cooling cylinder section, and the negative pressure fan is connected to the porous cylindrical component through a recovery pipe.

8. The cooling system for melt spinning as described in claim 1, characterized in that: The spinning box is equipped with a metering pump.

9. The cooling system for melt spinning as described in claim 1, characterized in that: The cooling cylinder section is provided with at least two sets.

10. The cooling system for melt spinning as described in claim 1, characterized in that: The cooling system also includes a lifting assembly connected to the spinning box and capable of driving the spinning box to move up or down.

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