Production method of special-shaped extra-black polyester fiber

Abstract

The invention belongs to the technical field of special-shaped polyester fibers, and relates to a production method of a special-shaped extra-black polyester fiber, which comprises the following steps: extruding a polyester melt containing black master batch through a special-shaped section spinneret plate, cooling, pre-network oiling, a guide wheel I, a guide wheel II, a GR1 godet, a pre-network, a GR2 godet, a guide wheel III and winding in sequence to obtain the special-shaped extra-black polyester fiber, in the polyester melt containing the black master batch, the content of the black master batch is more than 7wt%; pre-interlacing oiling refers to oiling while pre-interlacing the tows; the pre-interlacing air channel is communicated with the oil mist channel at the outlet, when compressed air is sprayed out through the pre-interlacing air channel, oil mist in the oil mist channel is pressed to the pre-interlacing air channel, and the oil mist and the compressed air meet at the outlet of the pre-interlacing air channel and are mixed to jointly act on tows, so that the tows are pre-interlaced and oiled at the same time. According to the invention, the oil mist channel is additionally arranged on the pre-interlacing air channel, so that the purposes of oiling and bundling wires at the same time are achieved; and meanwhile, low-resistance uniform oiling can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of special-shaped polyester fibers and relates to a production method of special-shaped special black polyester fibers. Background Art

[0002] The production process of special-shaped black polyester fiber usually melts the black masterbatch through a screw, then extrude and inject it into a normal melt conveying pipeline, and then fully mixes it through a dynamic mixer, and then passes through a spinning box, cooling, oiling, pre-networking, GR1, GR2 and winding head. Since the amount of black masterbatch added determines the blackness of the product, when producing special black yarn, the addition ratio of black masterbatch even reaches more than 7%. This high proportion of black masterbatch addition, coupled with the larger specific surface area of ​​special-shaped fibers, leads to a significant increase in the friction between the tow and the wire guide porcelain parts; at the same time, since the tow passes through the wire guide porcelain parts, the wire cutter porcelain parts, the pre-networking porcelain parts and the wire guide porcelain parts on the winding machine after oiling, the friction between the tow and these wire guide porcelain parts will produce more black powder and fluff, which will inevitably lead to a decrease in fiber strength and affect product quality.

[0003] To solve the above problems, the literature (Production process of 430dtex / 288f special black polyester pre-oriented yarn [J]. Synthetic Fibers. 2023, 52(3): 22-24) records that by using a special oil nozzle and optimizing the oiling bundle position, oil concentration and oil content, the friction coefficient of the fiber is reduced, thereby reducing the fuzz. However, for porous special-shaped black fibers, the oil permeability is poor, and conventional parameter optimization alone cannot completely solve the friction between the yarn bundle and the porcelain part.

[0004] Therefore, it is of great significance to study a production method of special-shaped black polyester fiber to solve the above-mentioned problems existing in the prior art. Summary of the invention

[0005] The purpose of the invention is to solve the problems existing in the prior art and provide a method for producing special-shaped black polyester fibers.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A method for producing special-shaped black polyester fibers, wherein a polyester melt containing black masterbatch is extruded through a special-shaped cross-section spinneret, and then subjected to cooling, pre-networking and oiling, guide wheel I, guide wheel II, GR1 godet roller, pre-networking, GR2 godet roller, guide wheel III and winding to obtain the special-shaped black polyester fibers;

[0008] In the polyester melt containing black masterbatch, the content of black masterbatch is more than 7wt%;

[0009] Pre-network oiling means oiling the tow while pre-networking it; the pre-network air duct is connected to the oil mist passage at the outlet. When compressed air is ejected through the pre-network air duct, the oil mist in the oil mist passage is pressed into the pre-network air duct, meets and mixes with the compressed air at the outlet of the pre-network air duct, and then acts on the tow together, so as to realize oiling the tow while pre-networking it.

[0010] During pre-network oiling, the pressure in the pre-network air duct is 0.03 - 0.07 MPa.

[0011] For the pre-network oiling method adopted in the present invention, an oil mist passage is added to the pre-network air duct. When compressed air passes through the pre-network air duct and is ejected from the nozzle, due to Bernoulli's principle, the pre-network air duct is connected to the oil mist passage, and the pre-network air duct is constantly blowing air, which easily causes a negative pressure to form in the oil mist passage behind the oil mist flow limiting valve. The pressure in the oil mist passage is greater than the pressure at the edge of the pre-network air flow, so that the oil mist in the oil mist passage is pressed into the air flow and sprayed on the filaments together with the air flow, thus achieving the purpose of oiling the filaments and bundling them simultaneously.

[0012] For a profiled cross-section tow, its specific surface area is large. When using an oil nozzle for oiling, the oil hole wire channel needs to be wide. And in order to make the tow stick tightly to the oil nozzle and improve the oiling uniformity, a wire guiding hook needs to be installed below the oil nozzle. However, sticking tightly to the oil nozzle and installing the wire guiding hook both increase the oiling friction resistance, which will lead to uneven oiling. At the same time, for super black fibers, since more than 7% of the black masterbatch (the black masterbatch is a color masterbatch raw material produced by processes such as carbon black, carrier, and additive injection molding) is added, and carbon black has strong oil absorption, mainly manifested as carbon black particles being easily precipitated on the fiber surface, resulting in a hard feel for single fibers. If using an oil nozzle for oiling, the friction resistance is greater, which will make the tow have poor bundling property. While the pre-network oiling adopted in the present invention, the tow and the network porcelain parts do not directly contact, and the friction resistance is relatively small, which can achieve low-resistance and uniform oiling, and effectively solve the above problems.

[0013] In the prior art, the purpose of pre-networking is to form "interlaced and entangled" network nodes to improve the bundling property, and a relatively high air pressure needs to be adopted. However, if the network air pressure is too large, it is easy to blow the oil mist out of the tow, resulting in problems such as uneven oiling of the tow and inconsistent oil film thickness on the tow surface, and then hairiness occurs. Especially for profiled cross-sections, such as the "king" - shaped cross-section, due to the large pre-network air pressure, it is easier to cause a very thin oil film at the front end of the "king" - shaped profile, resulting in problems such as hairiness.

[0014] The present invention uses an oil mist generator to atomize the oil agent, and then uses the pre-networked compressed gas to mix and act on the tow. After the bonding effect is completed, each single filament can be evenly contacted with the oil mist, and the oiling is more uniform; the low-pressure injection working mode is adopted to ensure that the fiber is always in the center of the nozzle wire channel, avoiding the friction between the fiber and the nozzle wire channel porcelain parts in the conventional nozzle. By improving the uniformity of oiling, the bonding can also be well guaranteed, and adding a pre-network between the GR1 wire guide roller and the GR2 wire guide roller will also improve the bonding.

[0015] As the preferred technical solution:

[0016] As described above, a method for producing special-shaped black polyester fibers, the device used for pre-network oiling includes a pre-network base and a pre-network airway and an oil mist channel arranged inside the pre-network base, and also includes a pre-network nozzle, an air source, a pre-network air pipe, an oil mist generator and an oil mist pipe; the outlet of the pre-network airway is interconnected with the outlet of the oil mist channel; the pre-network nozzle is installed at the outlet of the pre-network airway; the air source is connected to the pre-network airway through the pre-network air pipe, and the pre-network air pipe and the pre-network airway are connected through a pre-network air pipe joint; the oil mist generator is connected to the oil mist channel through the oil mist pipe, and the oil mist pipe and the oil mist channel are connected through an oil mist pipe joint.

[0017] In the above-mentioned method for producing special-shaped black polyester fibers, an oil mist flow limiting valve is provided near the inlet of the oil mist channel.

[0018] In the production method of a special-shaped black polyester fiber as described above, the diameter of the pre-network airway is 1.5-2 mm, the diameter of the oil mist pipe before the oil mist limiting valve is 4-6 mm, the pressure is 0.04-0.06 MPa, the diameter of the oil mist channel after the oil mist limiting valve is 0.75-1 mm, the pressure is 0.02-0.03 MPa, and the angle between the oil mist channel and the pre-network airway is 10°-45°; when the angle between the oil mist channel and the pre-network airway is less than 10°, the pipeline may be easily deformed due to the high air pressure; when it is greater than 45°, the oil mist may easily flow back to the oil mist channel in the pre-network airway.

[0019] In the above-mentioned production method of special-shaped black polyester fiber, the pre-network oiling position is 700-800 mm below the spinneret; the pre-network nozzle wire path length is 3-4 cm, and the pre-network nozzle outlet is located in the middle of the pre-network nozzle wire path, that is, 1.5-2 cm from the pre-network nozzle wire path; the purpose of such arrangement is to reduce the dispersion of oil mist and reduce the shaking of the yarn bundle in the pre-network wire path, so as to avoid the problem of high oil consumption;

[0020] When the pre-network is oiled, the temperature of the compressed air in the pre-network airway is 30-40°C; when the pre-network is oiled, the constant temperature air supply is obtained through the temperature regulating compressed air system; the temperature regulating compressed air system includes a pressure regulating valve, an insulated air pipe, a heat exchange unit, a temperature control meter and a temperature sensor;

[0021] The gas source is connected to the pre-network gas pipe through an insulated gas pipe; along the direction from the gas source to the pre-network gas pipe, a pressure regulating valve and a heat exchange unit are sequentially arranged on the insulated gas pipe;

[0022] The pressure regulating valve is used to regulate the pressure of the gas transported by the gas source to obtain compressed air that meets the process requirements; the heat exchange unit includes an inlet pipe, an outlet pipe and an inlet valve; hot water is introduced into the inlet pipe, and the hot water exchanges heat with the compressed air passing through the heat exchange unit; the inlet valve is arranged on the inlet pipe, and the inlet valve is used to control the flow of hot water entering the inlet pipe to adjust the temperature of the compressed air;

[0023] The temperature controller is installed on the pre-network air pipe near the pre-network air pipe joint, and the temperature sensor is installed at the pre-network air pipe joint. The temperature controller is electrically connected to the temperature sensor and the water inlet valve respectively. The temperature sensor is used to detect the temperature of the compressed air after heat exchange and send the detection result to the temperature controller. The temperature controller compares the detection result with the set temperature. When the two are not equal, the temperature controller controls the opening of the water inlet valve to adjust the temperature of the compressed air.

[0024] The compressed air passes through the pressure regulating valve and the insulated air pipe to enter the heat exchange unit. The temperature of the compressed air entering the heat exchange unit rises to the set temperature and then passes through the insulated air pipe to reach the pre-network air pipe. When the temperature sensor detects that the temperature deviates from the set temperature, the temperature control meter controls the opening of the regulating valve to control the water inlet of the heat exchange unit, thereby achieving the purpose of adjusting the compressed air temperature.

[0025] The distance between the pre-network oiling position and the spinneret is relatively short, because the special black shaped fiber has a large specific surface area and large friction with the air, resulting in excessive tension. The tension can be reduced by shortening the distance; however, the pre-network oiling position is too close to the spinneret and close to the cooling wind, resulting in a relatively low oiling temperature, and then the fluidity of the oil mist is poor, resulting in poor oil permeability of the shaped fibers, especially the multi-F shaped fibers. The present invention heats the pre-network air pressure to 30-40°C, thereby improving the fluidity of the oil mist on the surface of the filament bundle and thus improving the oil permeability.

[0026] In the above-mentioned method for producing special-shaped black polyester fibers, the pre-network nozzle is a three-hole jet pre-network nozzle, and the adjacent jet holes are distributed at 120 degrees on the same circumference. The three-hole jet pre-network nozzle can reduce the friction between the tow and the network nozzle, and improve the uniformity of oiling, so that the oil agent has better permeability.

[0027] In the above-mentioned method for producing special-shaped black polyester fibers, the length of the GR1 and GR2 godet rollers is 200 mm, and the interval between the wires on the GR1 and GR2 godet rollers is 13 to 15 mm. The interval between the wires on GR1 and GR2 is changed from the conventional 2 to 3 mm to 13 to 15 mm. Since the special-shaped black polyester fibers have poor oiling uniformity, static electricity and other problems are easily generated when the spinning speed is relatively high. By increasing the interval, static electricity can also be reduced; in order to achieve a wire interval of 13 to 15 mm, the length of the GR1 and GR2 godet rollers is increased from the conventional 80 mm to 200 mm.

[0028] According to the method for producing special-shaped black polyester fibers as described in any one of the above items, no black powder is observed on the porcelain parts of the guide wheels I, II and III during continuous production for 72 hours.

[0029] The above-mentioned method for producing special-shaped black polyester fibers has specifications of 185-300dtex / 144-288f, a hair reduction rate of ≤0.3%, and a breaking strength of ≥2.3cN / dtex.

[0030] Beneficial effects:

[0031] (1) The present invention provides a method for producing special-shaped black polyester fibers, wherein an oil mist channel is added to the pre-network air channel. When compressed air is ejected from the nozzle through the pre-network air channel, due to the Bernoulli principle, the pressure in the oil mist channel is greater than the pressure at the edge of the pre-network air flow, so that the oil mist in the oil mist channel is pressed into the air flow and sprayed onto the yarn along with the air flow, thereby achieving the purpose of simultaneously oiling and bundling the yarn, so that each single yarn can be evenly contacted with the oil mist at the same time, and the oiling is more uniform.

[0032] (2) The present invention provides a method for producing special-shaped black polyester fibers. During pre-network oiling, the filament bundles are not in direct contact with the network porcelain parts, and the friction resistance is relatively small, so low-resistance and uniform oiling can be achieved. At the same time, a low-pressure jet working mode is adopted to ensure that the fibers are always in the center of the nozzle wire path, avoiding problems such as friction between the fibers and the nozzle wire path porcelain parts in conventional nozzles. By improving the uniformity of oiling, the adhesion can be well guaranteed, and adding a pre-network between the GR1 wire guide roller and the GR2 wire guide roller will also improve the adhesion. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of pre-network oiling;

[0034] Figure 2 This is a schematic diagram of the wire bundle entering the guide wheel;

[0035] Among them, 1-air source, 2-insulated air pipe, 3-pre-network air pipe, 4-pre-network air channel, 5-pre-network air pipe connector, 6-oil mist channel, 7-oil mist generator, 8-oil mist pipe, 9-oil mist pipe connector, 10-oil mist flow limiting valve, 11-pressure regulating valve, 12-temperature control meter, 13-temperature sensor, 14-water inlet pipe, 15-water outlet pipe, 16-water inlet valve, 17-guide wheel I, 18-pre-network nozzle, 19-filament bundle, 20-guide wheel II, 21-guide wheel bracket, 22-GR1 wire guide roller, 23-pre-network device, 24-GR2 wire guide roller, 25-guide wheel III. DETAILED DESCRIPTION

[0036] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0037] The test methods involved in the performance indicators of the present invention are as follows:

[0038] Fiber specification: Specification = linear density / number of holes. The linear density is calculated by measuring the mass of a 10,000-meter sample in accordance with GB / T 14343-2008 “Test method for linear density of chemical filaments”. The unit is dtex.

[0039] Downgrading rate of hairy silk: Hairy silk will be downgraded if there are more than 2 single-filament breakage defects on the surface of each silk roll. Downgrading rate of hairy silk = number of downgraded hairy silk × 100% / total number of silks.

[0040] Breaking strength: referring to GB / T 14344-2022 "Test method for tensile properties of chemical fiber filaments", a fully automatic single yarn strength machine (model YG023B-Ⅱ) was used to measure the polyester fiber prepared in each embodiment. The specific process is as follows: the polyester fiber is first placed in an environment with a temperature of 20°C and a humidity of 65% for 4 hours, and then clamped by upper and lower clamps (clamping length of 500 mm), and a pre-tension of 0.05 cN / dtex is applied by a manipulator to stabilize the polyester fiber. At the beginning of the test, the lower clamp uniformly stretches the tow at a speed of 500 mm / min until the tow breaks, and the real-time data of the force sensor during the stretching process is recorded, and the relationship curve between strength and elongation is drawn through the data collection system. Finally, the breaking strength of the tow is obtained through data processing and analysis.

[0041] Example 1

[0042] A method for producing special-shaped black polyester fiber, the specific process is as follows:

[0043] like Figures 1-2 As shown, after the polyester melt containing 7wt% black masterbatch is extruded through a three-leaf cross-section spinneret, it is sequentially cooled, pre-networked and oiled, guided wheel I 17, guided wheel II 20, GR1 godet roller 22, pre-networked by a pre-networking device 23, GR2 godet roller 24, guided wheel III 25 and wound to obtain a three-leaf special black polyester fiber; wherein the guide wheel I 17 and the guide wheel II 20 are respectively mounted on their respective guide wheel brackets 21;

[0044] like Figure 1 As shown, pre-network oiling refers to oiling the filament bundle 19 while pre-networking; the pre-network oiling position is 700 mm below the spinneret; the device used for pre-network oiling includes a pre-network base, a pre-network nozzle 18, an air source 1, a pre-network air pipe 3, an oil mist generator 7, an oil mist pipe 8, and a pre-network air channel 4 and an oil mist channel 6 arranged inside the pre-network base;

[0045] The pre-network nozzle 18 is installed at the outlet of the pre-network airway 4; the pre-network nozzle 18 is a three-hole jet pre-network nozzle, and the adjacent jet holes are distributed at 120° on the same circumference; the pre-network nozzle wire path length is 3 cm, and the pre-network nozzle outlet is located in the middle of the pre-network nozzle wire path;

[0046] The outlet of the pre-network airway 4 is connected to the outlet of the oil mist channel 6. The diameter of the pre-network airway 4 is 1.5 mm. The diameter of the oil mist pipe 8 before the oil mist flow limiting valve 10 is 4 mm. The diameter of the oil mist channel 6 after the oil mist flow limiting valve is 0.75 mm. The angle between the oil mist channel 6 and the pre-network airway 4 is 10°.

[0047] When the pre-network is oiled, the pressure in the pre-network airway 4 is 0.03MPa, the pressure in the oil mist pipe 8 before the oil mist limiting valve 10 is 0.04MPa, and the pressure in the oil mist channel 6 after the oil mist limiting valve 10 is 0.02MPa;

[0048] When the compressed air is ejected through the pre-network air passage 4, the oil mist in the oil mist passage 6 is pressed into the pre-network air passage 4, and meets and mixes with the compressed air at the outlet of the pre-network air passage 4 before acting on the tow together, thereby achieving pre-networking and oiling of the tow at the same time;

[0049] When the pre-network is oiled, the temperature of the compressed air in the pre-network airway 4 is 30°C, and constant temperature air supply is obtained through the temperature-controlled compressed air system; the temperature-controlled compressed air system includes a pressure regulating valve 11, an insulated air pipe 2, a heat exchange unit, a temperature control meter 12 and a temperature sensor 13;

[0050] The gas source 1 is connected to the pre-network gas pipe 3 through the heat-insulating gas pipe 2, and then connected to the pre-network gas channel 4 through the pre-network gas pipe 3; the pre-network gas pipe 3 and the pre-network gas channel 4 are connected through the pre-network gas pipe joint 5; the oil mist generator 7 is connected to the oil mist channel 6 through the oil mist pipe 8, and the oil mist pipe 8 and the oil mist channel 6 are connected through the oil mist pipe joint 9; an oil mist flow limiting valve 10 is provided near the inlet of the oil mist channel 6;

[0051] Along the direction from the gas source 1 to the pre-network gas pipe 3, the insulated gas pipe 2 is provided with a pressure regulating valve 11 and a heat exchange unit in sequence;

[0052] The pressure regulating valve 11 is used to regulate the pressure of the gas delivered by the gas source 1 to obtain compressed air suitable for the process requirements; the heat exchange unit includes a water inlet pipe 14, a water outlet pipe 15 and a water inlet valve 16; hot water is introduced into the water inlet pipe 14, and the hot water exchanges heat with the compressed air passing through the heat exchange unit; the water inlet valve 16 is arranged on the water inlet pipe 14, and the water inlet valve 16 is used to control the flow rate of hot water entering the water inlet pipe 14 to adjust the temperature of the compressed air;

[0053] The temperature control meter 12 is installed on the pre-network air pipe 3 near the pre-network air pipe joint 5, and the temperature sensor 13 is installed at the pre-network air pipe joint 5. The temperature control meter 12 is electrically connected to the temperature sensor 13 and the water inlet valve 16 respectively. The temperature sensor 13 is used to detect the temperature of the compressed air after heat exchange and send the detection result to the temperature control meter 12. The temperature control meter 12 compares the detection result with the set temperature. When the two are not equal, the temperature control meter 12 controls the opening of the water inlet valve 16 to adjust the temperature of the compressed air;

[0054] The length of the GR1 godet roller and the GR2 godet roller is 200 mm, and the wire spacing on the GR1 godet roller and the GR2 godet roller is 13 mm.

[0055] The final three-leaf extra black polyester fiber had a specification of 185dtex / 144f, a hair degradation rate of 0.15%, and a breaking strength of 2.7cN / dtex. After 72 hours of continuous production, no black powder was found on the porcelain parts of guide wheels I, II, and III.

[0056] Example 2

[0057] A method for producing trilobal special black polyester fiber, the specific process is as follows:

[0058] After the polyester melt containing 7.3wt% of black masterbatch is extruded through a trilobal cross-section spinneret, it is sequentially cooled, pre-networked and oiled, guide wheel I, guide wheel II, GR1 godet roller, pre-networked, GR2 godet roller, guide wheel III and wound to obtain trilobal special black polyester fiber; wherein guide wheel I and guide wheel II are respectively installed on their respective guide wheel brackets;

[0059] Pre-network oiling refers to oiling the tow while pre-networking; the pre-network oiling position is 720mm below the spinneret; the device used for pre-network oiling includes a pre-network base, a pre-network nozzle, an air source, a pre-network air pipe, an oil mist generator, an oil mist pipe, and a pre-network air channel and an oil mist channel arranged inside the pre-network base;

[0060] The pre-network nozzle is installed at the outlet of the pre-network airway; the pre-network nozzle is a three-hole jet pre-network nozzle, and adjacent jet holes are distributed at 120° on the same circumference; the length of the pre-network nozzle wire path is 3.5 cm, and the outlet of the pre-network nozzle is located in the middle of the pre-network nozzle wire path;

[0061] The outlet of the pre-network airway is connected to the outlet of the oil mist channel. The diameter of the pre-network airway is 1.6 mm. The diameter of the oil mist pipe before the oil mist flow limiting valve is 5 mm. The diameter of the oil mist channel after the oil mist flow limiting valve is 0.8 mm. The angle between the oil mist channel and the pre-network airway is 20°.

[0062] When the pre-network is oiled, the pressure in the pre-network airway is 0.04MPa, the pressure in the oil mist pipe before the oil mist limiting valve is 0.05MPa, and the pressure in the oil mist channel after the oil mist limiting valve is 0.03MPa;

[0063] When the compressed air is ejected through the pre-network airway, the oil mist in the oil mist channel is pressed into the pre-network airway, and meets and mixes with the compressed air at the outlet of the pre-network airway before acting on the tow together, thereby achieving pre-networking and oiling of the tow at the same time.

[0064] When the pre-network is oiled, the temperature of the compressed air in the pre-network airway is 35°C, and constant temperature air supply is obtained through the temperature-controlled compressed air system; the temperature-controlled compressed air system includes a pressure regulating valve, an insulated air pipe, a heat exchange unit, a temperature control meter and a temperature sensor;

[0065] The gas source is connected to the pre-network gas pipe through the heat-insulating gas pipe, and then connected to the pre-network airway through the pre-network gas pipe, and the pre-network gas pipe and the pre-network airway are connected through the pre-network gas pipe joint; the oil mist generator is connected to the oil mist channel through the oil mist pipe, and the oil mist pipe and the oil mist channel are connected through the oil mist pipe joint; an oil mist flow limiting valve is provided near the inlet of the oil mist channel;

[0066] Along the direction from the gas source to the pre-network gas pipe, a pressure regulating valve and a heat exchange unit are arranged on the heat-insulated gas pipe in sequence;

[0067] The pressure regulating valve is used to regulate the pressure of the gas transported by the gas source to obtain compressed air that meets the process requirements; the heat exchange unit includes an inlet pipe, an outlet pipe and an inlet valve; hot water is introduced into the inlet pipe, and the hot water exchanges heat with the compressed air passing through the heat exchange unit; the inlet valve is arranged on the inlet pipe, and the inlet valve is used to control the flow of hot water entering the inlet pipe to adjust the temperature of the compressed air;

[0068] The temperature control meter is installed on the pre-network gas pipe near the pre-network gas pipe joint, and the temperature sensor is installed at the pre-network gas pipe joint. The temperature control meter is electrically connected to the temperature sensor and the water inlet valve respectively. The temperature sensor is used to detect the temperature of the compressed air after heat exchange and send the detection result to the temperature control meter. The temperature control meter compares the detection result with the set temperature. When the two are not equal, the temperature control meter controls the opening of the water inlet valve to adjust the temperature of the compressed air.

[0069] The length of the GR1 godet roller and the GR2 godet roller is 200 mm, and the wire spacing on the GR1 godet roller and the GR2 godet roller is 14 mm.

[0070] The final three-leaf special black polyester fiber had a specification of 200dtex / 144f, a hair degradation rate of 0.17%, and a breaking strength of 2.61cN / dtex. After 72 hours of continuous production, no black powder was found on the porcelain parts of guide wheels I, II, and III.

[0071] Example 3

[0072] A method for producing flat special black polyester fiber, the specific process is as follows:

[0073] After the polyester melt containing 7.5wt% of black masterbatch is extruded through a flat cross-section spinneret, it is sequentially cooled, pre-networked and oiled, guide wheel I, guide wheel II, GR1 godet roller, pre-networked, GR2 godet roller, guide wheel III and wound to obtain a flat ultra-black polyester fiber; wherein the guide wheel I and the guide wheel II are respectively mounted on their respective guide wheel brackets;

[0074] Pre-network oiling refers to oiling the tow while pre-networking; the pre-network oiling position is 800mm below the spinneret; the device used for pre-network oiling includes a pre-network base, a pre-network nozzle, an air source, a pre-network air pipe, an oil mist generator, an oil mist pipe, and a pre-network air channel and an oil mist channel arranged inside the pre-network base;

[0075] The pre-network nozzle is installed at the outlet of the pre-network airway; the pre-network nozzle is a three-hole jet pre-network nozzle, and adjacent jet holes are distributed at 120 degrees on the same circumference; the length of the pre-network nozzle wire path is 4 cm, and the outlet of the pre-network nozzle is located in the middle of the pre-network nozzle wire path;

[0076] The outlet of the pre-network airway is connected to the outlet of the oil mist channel. The diameter of the pre-network airway is 2 mm, the diameter of the oil mist pipe before the oil mist flow limiting valve is 6 mm, the diameter of the oil mist channel after the oil mist flow limiting valve is 1 mm, and the angle between the oil mist channel and the pre-network airway is 30°.

[0077] When the pre-network is oiled, the pressure in the pre-network airway is 0.06MPa, the pressure in the oil mist pipe before the oil mist limiting valve is 0.06MPa, and the pressure in the oil mist channel after the oil mist limiting valve is 0.03MPa;

[0078] When the compressed air is ejected through the pre-network airway, the oil mist in the oil mist channel is pressed into the pre-network airway, and meets and mixes with the compressed air at the outlet of the pre-network airway before acting on the tow together, thereby achieving pre-networking and oiling of the tow at the same time.

[0079] When the pre-network is oiled, the temperature of the compressed air in the pre-network airway is 40°C, and constant temperature air supply is obtained through the temperature-controlled compressed air system; the temperature-controlled compressed air system includes a pressure regulating valve, an insulated air pipe, a heat exchange unit, a temperature control meter and a temperature sensor;

[0080] The gas source is connected to the pre-network gas pipe through the heat-insulating gas pipe, and then connected to the pre-network airway through the pre-network gas pipe, and the pre-network gas pipe and the pre-network airway are connected through the pre-network gas pipe joint; the oil mist generator is connected to the oil mist channel through the oil mist pipe, and the oil mist pipe and the oil mist channel are connected through the oil mist pipe joint; an oil mist flow limiting valve is provided near the inlet of the oil mist channel;

[0081] Along the direction from the gas source to the pre-network gas pipe, a pressure regulating valve and a heat exchange unit are arranged on the heat-insulated gas pipe in sequence;

[0082] The pressure regulating valve is used to regulate the pressure of the gas transported by the gas source to obtain compressed air that meets the process requirements; the heat exchange unit includes an inlet pipe, an outlet pipe and an inlet valve; hot water is introduced into the inlet pipe, and the hot water exchanges heat with the compressed air passing through the heat exchange unit; the inlet valve is arranged on the inlet pipe, and the inlet valve is used to control the flow of hot water entering the inlet pipe to adjust the temperature of the compressed air;

[0083] The temperature control meter is installed on the pre-network gas pipe near the pre-network gas pipe joint, and the temperature sensor is installed at the pre-network gas pipe joint. The temperature control meter is electrically connected to the temperature sensor and the water inlet valve respectively. The temperature sensor is used to detect the temperature of the compressed air after heat exchange and send the detection result to the temperature control meter. The temperature control meter compares the detection result with the set temperature. When the two are not equal, the temperature control meter controls the opening of the water inlet valve to adjust the temperature of the compressed air.

[0084] The length of the GR1 godet roller and the GR2 godet roller is 200 mm, and the wire spacing on the GR1 godet roller and the GR2 godet roller is 15 mm.

[0085] The final flat extra-black polyester fiber had a specification of 278dtex / 288f, a hair degradation rate of 0.24%, and a breaking strength of 2.37cN / dtex. After 72 hours of continuous production, no black powder was found on the porcelain parts of guide wheels I, II, and III.

[0086] Example 4

[0087] A method for producing flat special black polyester fiber, the specific process is as follows:

[0088] After the polyester melt containing 7.9wt% of black masterbatch is extruded through a flat cross-section spinneret, it is sequentially cooled, pre-networked and oiled, guide wheel I, guide wheel II, GR1 godet roller, pre-networked, GR2 godet roller, guide wheel III and wound to obtain a flat special black polyester fiber; wherein the guide wheel I and the guide wheel II are respectively installed on their respective guide wheel brackets;

[0089] Pre-network oiling refers to oiling the tow while pre-networking; the pre-network oiling position is 770mm below the spinneret; the device used for pre-network oiling includes a pre-network base, a pre-network nozzle, an air source, a pre-network air pipe, an oil mist generator, an oil mist pipe, and a pre-network air channel and an oil mist channel arranged inside the pre-network base;

[0090] The pre-network nozzle is installed at the outlet of the pre-network airway; the pre-network nozzle is a three-hole jet pre-network nozzle, and adjacent jet holes are distributed at 120° on the same circumference; the length of the pre-network nozzle wire path is 3.2 cm, and the outlet of the pre-network nozzle is located in the middle of the pre-network nozzle wire path;

[0091] The outlet of the pre-network airway is connected to the outlet of the oil mist channel. The diameter of the pre-network airway is 2 mm, the diameter of the oil mist pipe before the oil mist flow limiting valve is 6 mm, the diameter of the oil mist channel after the oil mist flow limiting valve is 1 mm, and the angle between the oil mist channel and the pre-network airway is 40°.

[0092] When the pre-network is oiled, the pressure in the pre-network airway is 0.07MPa, the pressure in the oil mist pipe before the oil mist limiting valve is 0.06MPa, and the pressure in the oil mist channel after the oil mist limiting valve is 0.03MPa;

[0093] When the compressed air is ejected through the pre-network airway, the oil mist in the oil mist channel is pressed into the pre-network airway, and meets and mixes with the compressed air at the outlet of the pre-network airway before acting on the tow together, thereby achieving pre-networking and oiling of the tow at the same time.

[0094] When the pre-network is oiled, the temperature of the compressed air in the pre-network airway is 32°C, and constant temperature air supply is obtained through the temperature-controlled compressed air system; the temperature-controlled compressed air system includes a pressure regulating valve, an insulated air pipe, a heat exchange unit, a temperature control meter and a temperature sensor;

[0095] The gas source is connected to the pre-network gas pipe through the heat-insulating gas pipe, and then connected to the pre-network airway through the pre-network gas pipe, and the pre-network gas pipe and the pre-network airway are connected through the pre-network gas pipe joint; the oil mist generator is connected to the oil mist channel through the oil mist pipe, and the oil mist pipe and the oil mist channel are connected through the oil mist pipe joint; an oil mist flow limiting valve is provided near the inlet of the oil mist channel;

[0096] Along the direction from the gas source to the pre-network gas pipe, a pressure regulating valve and a heat exchange unit are arranged on the heat-insulated gas pipe in sequence;

[0097] The pressure regulating valve is used to regulate the pressure of the gas transported by the gas source to obtain compressed air that meets the process requirements; the heat exchange unit includes an inlet pipe, an outlet pipe and an inlet valve; hot water is introduced into the inlet pipe, and the hot water exchanges heat with the compressed air passing through the heat exchange unit; the inlet valve is arranged on the inlet pipe, and the inlet valve is used to control the flow of hot water entering the inlet pipe to adjust the temperature of the compressed air;

[0098] The temperature control meter is installed on the pre-network gas pipe near the pre-network gas pipe joint, and the temperature sensor is installed at the pre-network gas pipe joint. The temperature control meter is electrically connected to the temperature sensor and the water inlet valve respectively. The temperature sensor is used to detect the temperature of the compressed air after heat exchange and send the detection result to the temperature control meter. The temperature control meter compares the detection result with the set temperature. When the two are not equal, the temperature control meter controls the opening of the water inlet valve to adjust the temperature of the compressed air.

[0099] The length of the GR1 godet roller and the GR2 godet roller is 200 mm, and the wire spacing on the GR1 godet roller and the GR2 godet roller is 13.5 mm.

[0100] The final flat extra-black polyester fiber had a specification of 300dtex / 288f, a hair degradation rate of 0.21%, and a breaking strength of 2.39cN / dtex. After 72 hours of continuous production, no black powder was found on the porcelain parts of guide wheels I, II, and III.

[0101] Example 5

[0102] A method for producing trilobal special black polyester fiber, the specific process is as follows:

[0103] After the polyester melt containing 8 wt% of black masterbatch is extruded through a three-leaf cross-section spinneret, it is sequentially cooled, pre-networked and oiled, guide wheel I, guide wheel II, GR1 godet roller, pre-networked, GR2 godet roller, guide wheel III and wound to obtain a three-leaf special black polyester fiber; wherein the guide wheel I and the guide wheel II are respectively mounted on their respective guide wheel brackets;

[0104] Pre-network oiling refers to oiling the tow while pre-networking; the pre-network oiling position is 750mm below the spinneret; the device used for pre-network oiling includes a pre-network base, a pre-network nozzle, an air source, a pre-network air pipe, an oil mist generator, an oil mist pipe, and a pre-network air channel and an oil mist channel arranged inside the pre-network base;

[0105] The pre-network nozzle is installed at the outlet of the pre-network airway; the pre-network nozzle is a three-hole jet pre-network nozzle, and adjacent jet holes are distributed at 120° on the same circumference; the length of the pre-network nozzle wire path is 3.8 cm, and the outlet of the pre-network nozzle is located in the middle of the pre-network nozzle wire path;

[0106] The outlet of the pre-network airway is connected to the outlet of the oil mist channel. The diameter of the pre-network airway is 1.8 mm. The diameter of the oil mist pipe before the oil mist flow limiting valve is 5 mm. The diameter of the oil mist channel after the oil mist flow limiting valve is 0.9 mm. The angle between the oil mist channel and the pre-network airway is 45°.

[0107] When the pre-network is oiled, the pressure in the pre-network airway is 0.05MPa, the pressure in the oil mist pipe before the oil mist limiting valve is 0.05MPa, and the pressure in the oil mist channel after the oil mist limiting valve is 0.03MPa;

[0108] When the compressed air is ejected through the pre-network airway, the oil mist in the oil mist channel is pressed into the pre-network airway, and meets and mixes with the compressed air at the outlet of the pre-network airway before acting on the tow together, thereby achieving pre-networking and oiling of the tow at the same time.

[0109] When the pre-network is oiled, the temperature of the compressed air in the pre-network airway is 38°C, and constant temperature air supply is obtained through the temperature-controlled compressed air system; the temperature-controlled compressed air system includes a pressure regulating valve, an insulated air pipe, a heat exchange unit, a temperature control meter and a temperature sensor;

[0110] The gas source is connected to the pre-network gas pipe through the heat-insulating gas pipe, and then connected to the pre-network airway through the pre-network gas pipe, and the pre-network gas pipe and the pre-network airway are connected through the pre-network gas pipe joint; the oil mist generator is connected to the oil mist channel through the oil mist pipe, and the oil mist pipe and the oil mist channel are connected through the oil mist pipe joint; an oil mist flow limiting valve is provided near the inlet of the oil mist channel;

[0111] Along the direction from the gas source to the pre-network gas pipe, a pressure regulating valve and a heat exchange unit are arranged on the heat-insulated gas pipe in sequence;

[0112] The pressure regulating valve is used to regulate the pressure of the gas transported by the gas source to obtain compressed air that meets the process requirements; the heat exchange unit includes an inlet pipe, an outlet pipe and an inlet valve; hot water is introduced into the inlet pipe, and the hot water exchanges heat with the compressed air passing through the heat exchange unit; the inlet valve is arranged on the inlet pipe, and the inlet valve is used to control the flow of hot water entering the inlet pipe to adjust the temperature of the compressed air;

[0113] The temperature control meter is installed on the pre-network gas pipe near the pre-network gas pipe joint, and the temperature sensor is installed at the pre-network gas pipe joint. The temperature control meter is electrically connected to the temperature sensor and the water inlet valve respectively. The temperature sensor is used to detect the temperature of the compressed air after heat exchange and send the detection result to the temperature control meter. The temperature control meter compares the detection result with the set temperature. When the two are not equal, the temperature control meter controls the opening of the water inlet valve to adjust the temperature of the compressed air.

[0114] The length of the GR1 godet roller and the GR2 godet roller is 200 mm, and the wire spacing on the GR1 godet roller and the GR2 godet roller is 14.5 mm.

[0115] The final three-leaf special black polyester fiber had a specification of 230dtex / 144f, a hair degradation rate of 0.23%, and a breaking strength of 2.48cN / dtex. After 72 hours of continuous production, no black powder was found on the porcelain parts of guide wheels I, II, and III.

Claims

1. A method for producing special-shaped black polyester fibers, characterized in that: After the polyester melt containing black masterbatch is extruded through a special-section spinneret, it is sequentially cooled, pre-networked and oiled, guide wheel I, guide wheel II, GR1 godet roller, pre-networked, GR2 godet roller, guide wheel III and wound to obtain special-shaped black polyester fiber. In the polyester melt containing black masterbatch, the content of black masterbatch is more than 7wt%; Pre-network oiling refers to oiling the tow while pre-networking; the pre-network airway is connected with the oil mist channel at the outlet, and when the compressed air is ejected through the pre-network airway, the oil mist in the oil mist channel is pressed into the pre-network airway, and meets and mixes with the compressed air at the outlet of the pre-network airway, and then acts on the tow together, so as to achieve oiling of the tow while pre-networking; When the pre-network is oiled, the pressure in the pre-network airway is 0.03-0.07MPa.

2. The method for producing special-shaped black polyester fiber according to claim 1, characterized in that: The device used for pre-network oiling includes a pre-network base and a pre-network air duct and an oil mist channel arranged inside the pre-network base, and also includes a pre-network nozzle, an air source, a pre-network air pipe, an oil mist generator and an oil mist pipe; the outlet of the pre-network air duct and the outlet of the oil mist channel are interconnected; the pre-network nozzle is installed at the outlet of the pre-network air duct; the air source is connected to the pre-network air duct through the pre-network air pipe, and the pre-network air pipe and the pre-network air duct are connected through a pre-network air pipe joint; the oil mist generator is connected to the oil mist channel through the oil mist pipe, and the oil mist pipe and the oil mist channel are connected through an oil mist pipe joint.

3. The method for producing special-shaped black polyester fiber according to claim 2, characterized in that: An oil mist flow limiting valve is provided near the inlet of the oil mist channel.

4. The method for producing special-shaped black polyester fiber according to claim 3, characterized in that: The diameter of the pre-network air duct is 1.5~2mm, the diameter of the oil mist pipe before the oil mist limiting valve is 4~6mm, and the pressure is 0.04~0.06MPa, the diameter of the oil mist channel after the oil mist limiting valve is 0.75~1mm, and the pressure is 0.02~0.03MPa, and the angle between the oil mist channel and the pre-network air duct is 10°~45°.

5. The method for producing special-shaped black polyester fiber according to claim 4, characterized in that: The pre-network oiling position is 700-800mm below the spinneret; the pre-network nozzle wire path length is 3-4cm, and the pre-network nozzle outlet is located in the middle of the pre-network nozzle wire path; When the pre-network is oiled, the temperature of the compressed air in the pre-network airway is 30-40°C; when the pre-network is oiled, the constant temperature air supply is obtained through the temperature regulating compressed air system; the temperature regulating compressed air system includes a pressure regulating valve, an insulated air pipe, a heat exchange unit, a temperature control meter and a temperature sensor; The gas source is connected to the pre-network gas pipe through an insulated gas pipe; along the direction from the gas source to the pre-network gas pipe, a pressure regulating valve and a heat exchange unit are sequentially arranged on the insulated gas pipe; The pressure regulating valve is used to regulate the pressure of the gas transported by the gas source to obtain compressed air that meets the process requirements; the heat exchange unit includes a water inlet pipe, a water outlet pipe and a water inlet valve; hot water is introduced into the water inlet pipe, and the hot water exchanges heat with the compressed air passing through the heat exchange unit; The water inlet valve is arranged on the water inlet pipe, and is used to control the flow of hot water into the water inlet pipe to adjust the temperature of the compressed air; The temperature controller is installed on the pre-network air pipe near the pre-network air pipe joint, and the temperature sensor is installed at the pre-network air pipe joint. The temperature controller is electrically connected to the temperature sensor and the water inlet valve respectively. The temperature sensor is used to detect the temperature of the compressed air after heat exchange and send the detection result to the temperature controller. The temperature controller compares the detection result with the set temperature. When the two are not equal, the temperature controller controls the opening of the water inlet valve to adjust the temperature of the compressed air.

6. The method for producing special-shaped black polyester fiber according to claim 5, characterized in that: The pre-network nozzle is a three-hole jet pre-network nozzle, and adjacent jet holes are distributed at 120 degrees on the same circumference.

7. The method for producing special-shaped black polyester fiber according to claim 1, characterized in that: The length of the GR1 godet roller and the GR2 godet roller is 200 mm, and the interval between the wires on the GR1 godet roller and the GR2 godet roller is 13 to 15 mm.

8. The method for producing special-shaped black polyester fibers according to any one of claims 1 to 7, characterized in that: After 72 hours of continuous production, no black powder was found on the porcelain parts of guide wheels I, II and III.

9. The method for producing special-shaped black polyester fiber according to claim 8, characterized in that: The specification of the special-shaped black polyester fiber is 185-300dtex / 144-288f, the hair degradation rate is ≤0.3%, and the breaking strength is ≥2.3cN / dtex.

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