A production process for producing melt-spun fine-denier PET with high gloss

Abstract

The present invention provides a production process for producing melt-spun fine-denier PET, including PET melt conveying, color paste conveying, entering the spinning box, FDY spinning and FDY finishing. The spinning temperature of the melt-spun fine-denier PET is 295°C, the cooling method adopts ring blowing, and when the ring blowing air temperature is 21°C, the ring blowing air humidity is 90%RH, the ring blowing process air pressure is 40Pa, and the ring blowing air speed is 0.35m / s, the product can be produced continuously and stably, the product quality is stable, and all indicators reach the level of excellent products.

Description

Technical Field

[0001] The invention relates to the technical field of polyester fully drawn yarns, and in particular to a production process for producing melt-spun fine-denier PET high-gloss fully drawn yarns. Background Art

[0002] As one of the synthetic fiber varieties, polyester has a large output, wide application, and simple process, accounting for more than 60% of the world's synthetic fiber output. It has excellent physical and mechanical properties and textile properties, is cheap, strong and durable, has good elasticity, is not easy to wrinkle and deform, is corrosion-resistant, has strong insulation, is easy to wash and dry, and is widely used in four-season clothing, bedding, interior decoration, national defense and military industry, and other industries.

[0003] In recent years, with the development of the global economy, changes in consumer concepts, and the emergence of new fiber products, new processes, and new technologies, people's pursuit of four-season clothing has become more and more personalized and high-end. As the chemical fiber variety with the largest total amount of use among all textile fibers, polyester has great development potential and a broad market for product differentiation. Developing differentiated polyester varieties, increasing product added value, and thus improving corporate economic benefits are crucial to the entire chemical fiber industry. Woven imitation silk fabrics and warp knitted fabrics made from fine-denier polyester high-gloss fully stretched yarn (FDY) have a soft and smooth feel and are often used to make outdoor sportswear, spring and summer high-end women's clothing, high-end underwear clothing, and home textile products.

[0004] Fine-denier polyester is shiny. Taking 40D / 48F FDY as an example, the preparation process of the existing technology has the following defects: the traditional fine-denier fully-drawn yarn has too little tension in the fiber itself, and the yarn is prone to shaking when passing through the ring blowing. If the traditional process parameters are used for production, melt fracture is prone to occur, the spinnability deteriorates, and hard-head yarns appear.

[0005] The patent document with application number 201310577811.3 discloses a system for producing POY and FDY composite polyester yarns from melt direct spinning stock solution and its preparation method, wherein the PET melt tower is connected to the melt cooler, the color paste silo and the melt cooler are respectively connected to the multi-coupler, the multi-coupler is connected to the dynamic mixer, the dynamic mixer is connected to the spinning box, and the spinning box is respectively connected to the POY device and the FDY device, thereby obtaining a system for producing POY and FDY composite polyester yarns from melt direct spinning stock solution. The system has a compact structure, a shorter production process, simpler operation, higher production efficiency, less energy consumption, more stable quality, reduced pollutant emissions, and is environmentally friendly. However, the production process parameters of the production system are not clear enough and need to be further regulated.

[0006] In view of this, it is necessary to invent a production process for producing melt-spun fine-denier PET with high gloss. Summary of the invention

[0007] In view of the shortcomings of the prior art, the object of the present invention is to provide a production process for producing melt-spun fine-denier PET with high gloss.

[0008] The technical solution adopted by the present invention to solve its technical problem is:

[0009] The invention discloses a preparation method for producing a melt-spun fine-denier PET high-gloss production process, comprising the following steps:

[0010] Step (1), PET melt conveying

[0011] The PET melt produced by polyester reaction in the PET melt tower is transported to the booster pump via a discharge pump and an insulation pipe. The PET melt is pressurized by the booster pump and transported to the melt cooler for cooling and then sent to the spinning line.

[0012] Step (2): Color paste delivery

[0013] Color paste is added to the color paste silo, and the color paste enters the multi-coupler through the color paste silo. The PET melt and the color paste are coupled through the multi-coupler, and after coupling, they are mixed through a static mixer. The static mixer is stirred and mixed to achieve uniform dispersion dyeing of the polyester melt;

[0014] Step (3), enter the spinning box

[0015] The melt evenly dyed by the static mixer enters the spinning manifold, which is connected to the spinning assembly of FDY;

[0016] Step (4), FDY spinning

[0017] After step (3), the fully drawn yarn is formed after passing through the spinneret in the spinning box. After being separated by the ring-blowing cooling device, the fully drawn yarn comes out through the tunnel and enters the oil spray nozzle bundling device for oiling, then enters the pre-networking device, and is preliminarily networked through the pre-networking nozzle. After being fully stretched by the first wire guide disk and the second wire guide disk, the yarn enters the main network, and then enters the winding machine for winding and forming to obtain FDY yarn cakes.

[0018] Among them, the fuel injector nozzle of the fuel injector clustering device is V-shaped;

[0019] The spinning temperature in the spinning box is 295-297°C;

[0020] The wind speed in the annular air cooling device is 0.25-0.55 m / s, the wind pressure is 20-60 Pa, the wind temperature is 17-23° C., and the humidity is 65-100% RH;

[0021] The main network air pressure is 0.2-0.3MPa, and the network density of the main network is controlled at 20-30 / m.

[0022] Step (5): FDY sorting and storage

[0023] The FDY spinning is subjected to long stocking tube color judgment, appearance inspection, and physical inspection, and then the qualified products are graded and packaged, and finally the packaged finished products are put into the finished product three-dimensional warehouse.

[0024] On the basis of the above scheme and as a preferred scheme of the above scheme, the intrinsic viscosity of the PET melt in step (1) is 0.635-0.645 dL·g, the melting point is 258-262°C, the b value is 2.0-6.30, and the L value is 85-90.

[0025] On the basis of the above scheme and as a preferred scheme of the above scheme, on the basis of the above scheme and as a preferred scheme of the above scheme, a melt filter is provided at the output end of the discharge pump described in step (1).

[0026] On the basis of the above scheme and as a preferred scheme of the above scheme, a color paste precise metering device is provided between the color paste silo and the multi-coupler in step (2), and a melt distribution valve is provided at the output end of the static mixer in step (2).

[0027] On the basis of the above scheme and as a preferred scheme of the above scheme, the first wire guide disc and the second wire guide disc described in step (4) are staggered in vertical direction, and the second wire guide disc is located above the first wire guide disc.

[0028] On the basis of the above scheme and as a preferred scheme of the above scheme, the temperature of the first wire guide disc is 90-100°C, and the speed is 1750-1950m / min; the temperature of the second wire guide disc is 130-140°C, and the speed is 4750-4950m / min.

[0029] On the basis of the above scheme and as a preferred scheme of the above scheme, the winding speed of the winding machine in step (4) is 4600-5000m / min.

[0030] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0031] After multiple optimizations of production processes and parameters, the melt-spun fine-denier PET high-gloss produced by the present invention is less likely to shake when passing through annular blowing, and has good spinnability, and does not have problems such as melt fracture and hard-headed yarns. After multiple optimizations of production processes and parameters, this variety has achieved continuous and stable production, and the product quality indicators have reached the level of superior products.

[0032] It should be appreciated that all combinations of the foregoing concepts, as well as additional concepts described in greater detail below, may be considered part of the present subject matter disclosure to the extent such concepts are not mutually inconsistent.

[0033] The foregoing and other aspects, embodiments and features of the present invention will be more fully understood from the following description. Other additional aspects of the present invention, such as the features and / or beneficial effects of the exemplary embodiments, will be apparent from the following description or will be learned from the practice of the specific embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0035] Figure 1 It is a structural diagram of the present invention;

[0036] Figure 2 It is a process flow chart of the present invention.

[0037] Among them, 1. PET melt tower; 2. discharge pump; 3. insulation pipe; 4. booster pump; 5. melt conveying cooler; 6. melt cooler; 7. multi-coupler; 8. color paste silo; 9. color paste precise metering device; 10. static mixer; 11. melt distribution valve; 12. spinning box; 13. ring blowing cooling device; 14. nozzle cluster oiling device; 15. pre-network device; 16. first guide wire disk; 17. second guide wire disk; 18. main network; 19. winder. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meanings understood by people with general skills in the field to which the present invention belongs.

[0039] The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular forms of "a", "an" or "the" and other similar words do not indicate a quantitative limitation, but indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before "include" or "comprise" cover the features, wholes, steps, operations, elements and / or components listed after "include" or "comprise", and do not exclude the existence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0040] As a textile raw material with high added value, the fabric woven from fine-denier polyester with high gloss is light and thin, has excellent soft and smooth feel, soft luster, good air permeability and drape, and has a unique style. The present invention controls and optimizes the corresponding production process parameters to produce fine-denier polyester with high gloss PET-FDY products (taking 40D / 48F as an example) with stable quality and excellent performance, thereby increasing the diversity and differentiation rate of the enterprise's products and improving the market competitiveness of the enterprise. The following will be described in detail with reference to examples.

[0041] Example 1

[0042] The preparation method of the melt-spinning fine denier PET high-gloss production process of this embodiment comprises the following steps:

[0043] (1) PET melt conveying

[0044] The PET melt produced by polyester reaction in the PET melt tower is transported to the booster pump via a discharge pump and an insulation pipe, and the PET melt is pressurized by the booster pump and transported to the melt cooler for cooling, and then sent to the spinning line; wherein the intrinsic viscosity of the PET melt is 0.640 dL·g, the melting point is 260°C, the b value is 4.0, and the L value is 88;

[0045] (2) Color paste transportation

[0046] Color paste is added to the color paste silo, and the color paste enters the multi-coupler through the color paste silo. The PET melt and the color paste are coupled through the multi-coupler, and after coupling, they are mixed through a static mixer. The static mixer is stirred and mixed to achieve uniform dispersion dyeing of the polyester melt;

[0047] (3) Entering the spinning box

[0048] The melt evenly dyed by the static mixer enters the spinning manifold, which is connected to the spinning assembly of FDY;

[0049] (4) FDY spinning

[0050] After step (3), the fully drawn yarn is formed after passing through the spinneret in the spinning box. After being separated by the ring-blowing cooling device, the fully drawn yarn comes out through the tunnel and enters the oil spray nozzle bundling device for oiling, then enters the pre-networking device, and is preliminarily networked through the pre-networking nozzle. After being fully stretched by the first wire guide disk and the second wire guide disk, the yarn enters the main network, and then enters the winding machine for winding and forming to obtain FDY yarn cakes.

[0051] Among them, the spinning temperature in the spinning box is 295°C; the wind speed in the ring-blowing cooling device is 0.35m / s, the wind pressure is 40Pa, the wind temperature is 21°C, and the humidity is 90%RH; the spinning temperature is 295°C, and the cooling method is ring blowing; the oiling rate of the filaments is controlled at 0.8%; the main network air pressure is 0.2MPa, and the network degree of the main network is controlled at 25 / m.

[0052] Step (5): FDY sorting and storage

[0053] The FDY spinning is subjected to long stocking tube color judgment, appearance inspection, and physical inspection, and then the qualified products are graded and packaged, and finally the packaged finished products are put into the finished product three-dimensional warehouse.

[0054] Furthermore, the temperature of the first wire guide disk is 95°C and the speed is 1850m / min; the temperature of the second wire guide disk is 135°C and the speed is 4850m / min; and the winding speed of the winding machine in step (4) is 4800m / min.

[0055] Example 2

[0056] The preparation method of the melt-spinning fine denier PET high-gloss production process of this embodiment comprises the following steps:

[0057] (1) PET melt conveying

[0058] The PET melt produced by polyester reaction in the PET melt tower is transported to the booster pump via a discharge pump and an insulation pipe, and the PET melt is pressurized by the booster pump and transported to the melt cooler for cooling, and then sent to the spinning line; wherein the intrinsic viscosity of the PET melt is 0.645 dL·g, the melting point is 261°C, the b value is 5.0, and the L value is 88;

[0059] (2) Color paste transportation

[0060] Color paste is added to the color paste silo, and the color paste enters the multi-coupler through the color paste silo. The PET melt and the color paste are coupled through the multi-coupler, and after coupling, they are mixed through a static mixer. The static mixer is stirred and mixed to achieve uniform dispersion dyeing of the polyester melt;

[0061] (3) Entering the spinning box

[0062] The melt evenly dyed by the static mixer enters the spinning manifold, which is connected to the spinning assembly of FDY;

[0063] (4) FDY spinning

[0064] After step (3), the fully drawn yarn is formed after passing through the spinneret in the spinning box. After being separated by the ring-blowing cooling device, the fully drawn yarn comes out through the tunnel and enters the oil spray nozzle bundling device for oiling, then enters the pre-networking device, and is preliminarily networked through the pre-networking nozzle. After being fully stretched by the first wire guide disk and the second wire guide disk, the yarn enters the main network, and then enters the winding machine for winding and forming to obtain FDY yarn cakes.

[0065] Among them, the spinning temperature in the spinning box is 296°C; the wind speed in the ring-blowing cooling device is 0.30m / s, the wind pressure is 50Pa, the wind temperature is 22°C, and the humidity is 95%RH; the spinning temperature is 296°C, the cooling method adopts ring blowing, and the oiling rate of the filaments is controlled at 0.7%; the main network air pressure is 0.3MPa, and the network degree of the main network is controlled at 30 / m.

[0066] Step (5): FDY sorting and storage

[0067] The FDY spinning is subjected to long stocking tube color judgment, appearance inspection, and physical inspection, and then the qualified products are graded and packaged, and finally the packaged finished products are put into the finished product three-dimensional warehouse.

[0068] Furthermore, the temperature of the first wire guide disk is 93°C and the speed is 1950m / min; the temperature of the second wire guide disk is 135°C and the speed is 4950m / min; and the winding speed of the winding machine in step (4) is 4900m / min.

[0069] Comparative Example 1

[0070] Commercially available fine denier polyester glossy 40D / 48F FDY was randomly selected for performance testing.

[0071] Performance Test:

[0072] (1) Linear density

[0073] According to GB / T 14343-2008 “Test method for linear density of chemical fiber filaments”, the linear density of the samples was tested.

[0074] (2) Strength test

[0075] According to GB / T 14344-2008 “Test method for tensile properties of chemical fiber filaments”, the samples were tested for properties such as breaking strength and breaking elongation.

[0076] (3) Unevenness of the strips

[0077] According to GB / T 14346-2015 “Test method for unevenness of chemical filament yarn - Capacitance method”, the samples were tested for unevenness of yarn.

[0078] (4) Thermal shrinkage performance test

[0079] According to GB / T 6505-2017 "Test method for thermal shrinkage of chemical fiber filaments (after treatment)", the thermal shrinkage performance of the samples was tested.

[0080] (5) Dyeing uniformity

[0081] According to GB / T 6508-2015 “Test method for dyeing uniformity of polyester filaments”, the samples were tested for heat shrinkage performance.

[0082] According to the relevant performance test standards, samples were taken from the above examples 1-2 and the comparative example, and then the linear density, strength, unevenness of the strips, heat shrinkage and dyeing uniformity and other performance tests were carried out. The physical properties are compared as shown in the following table:

[0083]

[0084] Combining the data analysis in the above table and the research on the process of polyester FDY 40D / 48F series, the following optimal production process parameters are obtained:

[0085] 1) The spinning temperature is 295°C, and the cooling method is ring blowing. The cooling conditions are: ring blowing air temperature 21°C, ring blowing air humidity 90% RH, ring blowing process air pressure 40Pa, and ring blowing air speed 0.35m / s; the oiling rate of the filaments is controlled at 0.7-0.9%.

[0086] 2) After several process adjustments, the temperatures of the first and second hot rollers are 95°C and 135°C, and the speeds of the first and second hot rollers are 1850m / min and 4850m / min; the stretching multiple is 2.2-2.8 times, and the fine denier polyester glossy 40D / 48F FDY yarn is usually controlled at a network density of 20-30 pcs / m at an air pressure of 0.2-0.3MPa; the winding speed is selected to be about 4800m / min.

[0087] Based on the parameter adjustments of Examples 1-2 of the present invention, it can be seen that the factors affecting the continuous and stable production of fine denier polyester spunbond and the stable and excellent product quality include: spinning temperature, cooling molding parameters, oil application amount, hot roller temperature, stretching multiple, main network pressure and winding speed.

[0088] Spinning temperature

[0089] In the melt direct spinning production process, spinning temperature is the most important process condition, and its selection is very important. Whether the spinning temperature is selected appropriately will directly affect the quality of the fiber and the normal spinning process. At the appropriate spinning temperature, the melt has good uniformity and rheology, good spinnability, and stable products. If the spinning temperature is too high, thermal decomposition will intensify, the molecular weight will decrease, the content of low molecular weight substances will increase, and the melt viscosity will decrease; it is easy to produce hair breakage, increase the breakage rate, more floating silk, serious sticking plate, and bubble silk, etc., the spinnability will deteriorate, and the quality index of the finished silk will decrease, which will seriously affect the fiber quality. On the contrary, if the spinning temperature is too low, the melt viscosity will be too high, the uniformity and fluidity of the melt will deteriorate, the transportation burden of the pump will increase, and the energy consumption will increase, which is not economical; the melt outlet extruded from the spinning assembly will swell and become heavier, and even melt fracture will occur, the spinnability will deteriorate, the probability of hard head silk will increase, the finished silk will be white, the luster will be dull, and the hand feel will be hard. The number of broken ends will increase during the winding and stretching process in the later process, and it may even be impossible to stretch, resulting in an increase in the number of spinning broken ends and hairy silk. Therefore, the spinning temperature must be strictly controlled when spinning fine denier polyester glossy 40D / 48F FDY.

[0090] Cooling molding

[0091] Cooling and forming is one of the important processes of melt spinning. In spinning production, the melt is turned into a solid state by cooling annular blowing. The unevenness of fiber strands is not only a concentrated reflection of the unevenness of the internal physical indicators of the fiber, but also an important indicator for measuring the quality level of FDY. The cooling conditions such as wind temperature, humidity, wind speed, and pressure have different effects on the unevenness of fiber strands.

[0092] Oiling amount

[0093] Fine denier yarn has a large specific surface area. During the spinning process, the friction between the fiber and the air and between the fiber and the metal equipment, and the high static electricity on the fiber, cause the yarn bundle to shake severely, which is not conducive to the single yarn bundling and leads to the inability to produce. Therefore, in actual production, a V-shaped oil nozzle is used to oil the fiber and bundle it, so that the oil forms a uniform oil film on the surface of the yarn to reduce the friction resistance between the fiber and the air and the friction between the fiber and the metal equipment, improve the cohesion and antistatic performance between the fibers, and improve the uniformity of the arrangement of the yarn when stretched. Therefore, the oil is required to have good penetration, spreading width and oil film strength; the TK-3588 oil produced independently by the Group is used in actual production.

[0094] Hot roller temperature

[0095] The stretching of polyester FDY is completed between the G1 and G2 godet. The speed of the first hot roller affects the stretching multiple of the filament bundle, which needs to be determined according to the spinning performance and the elongation of the filament bundle. The practice of the preparation process of the present invention shows that the temperature of the first hot roller must be 10°C-20°C higher than the glass transition temperature. After multiple process adjustments, the first and second hot roller temperatures are finally determined to be 95°C and 135°C, and the first and second hot roller speeds are 1850m / min and 4850m / min. This process is cold stretching, using an unheated godet. In order to compensate for the post-relaxation phenomenon of the filament, the G2 hot roller is used for heat setting. The hot roller is heated using a special heat medium. When the winding tension is 0.15cN / dtex, a relaxation rate of 0.4 to 0.85 can be obtained, and the package is well formed.

[0096] Stretching ratio

[0097] The speed ratio of the two wire guides is the stretching multiple. The strength of polyester fiber increases with the increase of the stretching multiple, while the elongation decreases accordingly. This is because under the action of tension, the macromolecules in the fiber are regularly arranged along the fiber axis, and the orientation degree increases. The strength of the fiber is mainly determined by the orientation degree of the macromolecules, which causes slippage and breakage, resulting in a decrease in orientation and strength. On the one hand, due to the small dpf, the stretching ratio of the spinneret becomes larger, which is easy to cause natural stretching and breakage; on the other hand, there are many single fibers, the tension during the spinning process is large, and the tension before winding is also large, which will increase the number of broken ends. Therefore, it is necessary to select a suitable stretching ratio to ensure stable production and reliable quality. Practice shows that the stretching multiple of polyester FDY is about 2.2 to 2.8 times.

[0098] Main network pressure

[0099] Fine denier polyester glossy 40D / 48F FDY is mainly used as the raw material for downstream weaving high-end fabrics, such as warp knitting, high-density woven fabrics, etc. Therefore, it is required that the yarn has good cohesion. The winding tension of fine denier yarn is large, and due to the large number of single fibers, the cohesion performance will deteriorate. In addition, twisting cannot be performed during high-speed winding, so a network nozzle is installed after the winding drafting roller for network processing, so that the yarn bundles are cohesive and entangled to increase the cohesion of the yarns, improve the cohesion performance, and ensure smooth unwinding. The dpf of fine denier yarn is small, and the torque effect of the yarn during network processing is small, so a higher network degree can be obtained under lower air pressure. According to the requirements of downstream users and combined with on-site production conditions, the network degree of fine denier polyester glossy 40D / 48F FDY yarn is usually controlled at 20-30 pieces / m at an air pressure of 0.2-0.3MPa.

[0100] Winding speed

[0101] Due to high-speed spinning followed by high-speed stretching, the stress in the yarn is difficult to relax. By changing the different stretching multiples, fully stretched yarns with a breaking elongation of more than 35% can be obtained. In principle, the speed of the winding head must be lower than the speed of the second stretching, so as to ensure that the stretched yarns can be shrunk to a certain extent with low tension, so as to obtain satisfactory finished product quality and package. Combined with the on-site production situation, the winding speed of polyester FDY is selected to be around 4800m / min.

[0102] According to the feedback from downstream manufacturers, the FDY product produced by the melt-spinning fine-denier PET high-gloss production process used in the present invention is suitable for weaving, dyeing and finishing of textiles, has a very good effect, and fully meets the requirements of post-processing.

[0103] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A production process for producing melt-spun fine-denier PET with high gloss, characterized in that: The following steps are involved: Step (1), PET melt conveying The PET melt produced by polyester reaction in the PET melt tower is transported to the booster pump via a discharge pump and an insulation pipe. The PET melt is pressurized by the booster pump and transported to the melt cooler for cooling and then sent to the spinning line. Step (2): Color paste delivery Color paste is added to the color paste silo, and the color paste enters the multi-coupler through the color paste silo. The PET melt and the color paste are coupled through the multi-coupler, and after coupling, they are mixed through a static mixer. The static mixer is stirred and mixed to achieve uniform dispersion dyeing of the polyester melt; Step (3), enter the spinning box The melt evenly dyed by the static mixer enters the spinning manifold, which is connected to the spinning assembly of FDY; Step (4), FDY spinning After step (3), the fully drawn yarn is formed after passing through the spinneret in the spinning box. After being separated by the ring-blowing cooling device, the fully drawn yarn comes out through the tunnel and enters the oil spray nozzle bundling device for oiling, then enters the pre-networking device, and is preliminarily networked through the pre-networking nozzle. After being fully stretched by the first wire guide disk and the second wire guide disk, the yarn enters the main network, and then enters the winding machine for winding and forming to obtain FDY yarn cakes. Among them, the fuel injector nozzle of the fuel injector clustering device is V-shaped; The spinning temperature in the spinning box is 295-297°C; The wind speed in the annular air cooling device is 0.25-0.55 m / s, the wind pressure is 20-60 Pa, the wind temperature is 17-23° C., and the humidity is 65-100% RH; The main network air pressure is 0.2-0.3MPa, and the network density of the main network is controlled at 20-30 / m; Step (5): FDY sorting and storage The FDY spinning is subjected to long stocking tube color judgment, appearance inspection, and physical inspection, and then the qualified products are graded and packaged, and finally the packaged finished products are put into the finished product three-dimensional warehouse; The temperature of the first godet is 90-100°C, and the speed is 1750-1950 m / min; the temperature of the second godet is 130-140°C, and the speed is 4750-4950 m / min; The winding speed of the winding machine in step (4) is 4600-5000 m / min; The stretching ratio of polyester FDY is about 2.2 to 2.8 times; The FDY yarn network density is controlled at 20-30 pcs / m at an air pressure of 0.2-0.3MPa; The oiling rate of the silk strip is controlled at 0.7-0.9%.

2. A melt-spinning fine-denier PET high-gloss production process according to claim 1, characterized in that: The intrinsic viscosity of the PET melt in step (1) is 0.635-0.645 dL·g, the melting point is 258-262° C., the b value is 2.0-6.30, and the L value is 85-90.

3. The process for producing melt-spun fine-denier PET according to claim 1, characterized in that: The output end of the discharge pump described in step (1) is provided with a melt filter.

4. The process for producing melt-spun fine-denier PET according to claim 1, characterized in that: A color paste precise metering device is provided between the color paste silo and the multi-coupler in step (2), and a melt distribution valve is provided at the output end of the static mixer in step (2).

5. The process for producing melt-spun fine-denier PET according to claim 1, characterized in that: The first wire guide disc and the second wire guide disc described in step (4) are staggered in an up-and-down manner, and the second wire guide disc is located above the first wire guide disc.

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