Oil application device and use thereof, and method for applying oil to polyacrylonitrile-based carbon fiber precursor

Abstract

The present application relates to the technical field of fiber oiling, and particularly relates to an oiling device and application thereof, and an oiling method for polyacrylonitrile-based carbon fiber precursor. The oiling device comprises a shell, an oiling area is arranged in the shell, the oiling area is provided with three hollow godets connected through grooves, each of the hollow godets is provided with a spray hole, and the spray hole is arranged at an angle of 20-45 degrees below a vertical line, so that the sprayed oil is sprayed to a fiber bundle located below the hollow godet; according to the running direction of the fiber bundle, the first hollow godet is higher than the second hollow godet, and a horizontal included angle alpha is less than or equal to 15 degrees, and the second hollow godet and the third hollow godet are at the same height; a cooling component is arranged below each of the hollow godets, and a vertical distance from the cooling component to the fiber bundle is greater than or equal to 10 mm. The oiling device is used for fiber precursor oiling, and effectively reduces the accumulation of hair in the oil groove and the broken filament caused thereby.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of fiber oiling, in particular to an oiling device, application of the oiling device and an oiling method for polyacrylonitrile-based carbon fiber filaments. BACKGROUND

[0002] Carbon fiber is a special fiber mainly composed of carbon elements. The mass of the carbon fiber is lighter than that of aluminum, but the strength of the carbon fiber is higher than that of steel. The carbon fiber has corrosion resistance and the like, and has a significant anisotropy, softness and processability into various fabrics. The carbon fiber has high strength and modulus along the fiber axis direction, low density, good fatigue resistance, high temperature resistance in a non-oxidizing environment, a specific heat between non-metals and metals, a small thermal expansion coefficient and anisotropy, good corrosion resistance and good X-ray transmittance. The carbon fiber is a new generation of high-performance fiber.

[0003] The carbon fiber can be divided into polyacrylonitrile-based, viscose-based, pitch-based, vapor-phase-grown and activated carbon fibers according to the preparation method and raw material source. The polyacrylonitrile-based carbon fiber has been rapidly developed due to the simple preparation process and excellent carbon fiber performance, and has the largest production, accounting for more than 90% of the global carbon fiber production.

[0004] The preparation process of the carbon fiber filament can be divided into dry spinning, dry-jet wet spinning and wet spinning according to the spinning process. The dry spinning has the characteristics of high solid content and relatively dense filaments. The dry-jet wet spinning has the characteristics of high spinning speed and smooth surface. The wet spinning has the advantages of easy process control, less residual solvent in the fiber, deep grooves on the surface of the prepared carbon fiber and good bonding performance of the composite material, and is one of important methods for preparing carbon fiber filaments. The carbon fiber filament is the key to preparing high-performance carbon fiber, and the high-quality carbon fiber filament is the basis for preparing high-performance carbon fiber. How to prepare high-quality carbon fiber filaments has been the focus and difficulty of the carbon fiber preparation process. The wet spinning has relatively low solid content and relatively many surface defects, and therefore how to realize efficient, stable and low-defect preparation of the wet spinning filament is the key to the wet spinning filament.

[0005] The uniformity of the oiling process and the stable production of the oiling process are crucial for the continuity of the precursor production and the improvement of the mechanical properties of carbon fibers. Uneven oiling causes some fibers in a bundle of fibers to adhere more oil, and these additional adhered oil is more likely to separate from the fibers during subsequent drying densification, causing the oil to adhere to the drying densification roller, which affects the heat transfer efficiency of the hot roller, causing differences in drying densification between different fibers in a bundle of fibers, affecting the mechanical properties of the precursor, and further affecting the mechanical properties of the carbon fibers. It is difficult to completely eliminate the generation of broken fibers during the treatment process before oiling, and the accumulation of broken fibers in the oil tank will cause breakage in the oil tank, which not only affects the continuity of production, but also affects the uniformity of oiling. Therefore, improving the uniformity of the oiling process and reducing the accumulation of broken fibers in the oiling process have been a difficult and important problem in the oiling process of carbon fiber precursor production.

[0006] CN106868616A improves the uniformity of oiling by using a multi-stage oiling device combined with gradient oiling and multi-stage extrusion; CN109097846A uses a pressure rod vibration method to improve the uniformity of fiber oiling in the dry jet wet spinning process; CN110685029A uses a water immersion method before the second oiling to ensure the water content of the fibers before entering the second oiling, thereby improving the uniformity of oiling; CN111088535A, JP1989266214A and CN204455378U use ultrasonic oiling to improve the uniformity of fiber oiling; JP3891025B2 uses a method to control the spacing between the fibers leaving the oil tank to control the oiling process; JP1995011511A uses a method to increase the guide roller in the oil tank to improve the uniformity of the oiling process; JP1997268427A uses a method to control the area of the fibers leaving the bath and the pressure of the press roller to improve the uniformity of the oiling process in the dry jet wet spinning process; JP1997268478A uses a method to control the temperature in the oil bath tank to improve the uniformity of the oiling process.

[0007] The above-mentioned prior art all proposes a scheme to improve the uniformity of oiling, but the operation is not convenient or the structure is complex, and additional vibration, ultrasonic and other equipment are needed, which will bring additional control to the oiling process; at the same time, the above-mentioned prior art does not propose a specific scheme for broken fibers and process interruptions caused by accumulation of broken fibers in the oiling process, which has obvious deficiencies. SUMMARY

[0008] The purpose of the present application is to overcome the problems of uneven oiling and broken fiber accumulation in the oiling process of existing polyacrylonitrile-based carbon fiber precursor, to provide an oiling device and its application, and an oiling method for polyacrylonitrile-based carbon fiber precursor, which has the advantages of uniform oiling of the precursor and effective reduction of broken fiber accumulation.

[0009] In order to achieve the above-mentioned purpose, the first aspect of the present application provides an oiling device, which comprises a shell, wherein an oiling area is arranged in the shell, and the oiling area is provided with three hollow godets connected by a groove, each of the hollow godets is provided with a spray hole, and the spray hole is arranged at an angle θ of 20-45° below the vertical line, so that the sprayed oil is sprayed to the fiber bundle below the hollow godet.

[0010] Among them, according to the running direction of the fiber bundle, the first hollow godet is higher than the second hollow godet, and the horizontal angle α is ≤15°, and the second hollow godet and the third hollow godet are at the same height.

[0011] Among them, a cooling component is arranged below each of the hollow godets, and the vertical distance between the cooling component and the fiber bundle is ≥10mm.

[0012] The second aspect of the present application provides the application of the oiling device provided in the first aspect in the oiling of fiber precursor, preferably in the oiling of carbon fiber precursor, more preferably in the oiling of polyacrylonitrile carbon fiber precursor.

[0013] The third aspect of the present application provides an oiling method of polyacrylonitrile carbon fiber precursor, which is carried out in the oiling device provided in the first aspect; wherein the oiling method comprises: immersing the polyacrylonitrile-based carbon fiber precursor in the oiling area in the presence of a cooling medium, and performing secondary oiling with the oil sprayed through the spray hole of the hollow godet.

[0014] Compared with the prior art, the present application has the following advantages:

[0015] (1) The oiling device provided by the present application is provided with three hollow godets in the oiling area, and the horizontal angle α of the first hollow godet and the second hollow godet and the angle θ of the spray hole of the hollow godet are limited, especially combined with the flow of the oil sprayed through the spray hole, the mass transfer and heat transfer between the fresh oil and the fiber are strengthened, and the uniformity of oiling is improved; at the same time, the cooling component is directly arranged below the groove, so that the temperature around the fiber is more uniform, and the oiling process is more uniform;

[0016] Preferably, by controlling the structure and spatial position of the spray hole and the surface roughness of the hollow godet, some broken filaments in the oiling process are carried away by the oil in the spray hole in time, which can effectively reduce the accumulation of broken filaments in the oil groove and the broken filament caused by the accumulation;

[0017] (2) The oiling device provided by the present application is used for the oiling of fiber precursor, especially the oiling of polyacrylonitrile-based carbon fiber precursor, which has the advantages of good oiling uniformity and less accumulation of broken filaments, and can be used in the industrial production of high-performance carbon fiber precursor;

[0018] (3) The polyacrylonitrile-based carbon fiber precursor is oiled in the oiling device, so that the variation coefficient of the oil content of the oiled fiber can reach 3%, the number of broken ends caused by the broken ends can reach 9 / 10000 meters, and the broken end caused by the broken ends can be reduced to 20 days / time. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural diagram of an oiling device provided by the present application;

[0020] Figure 2 is a structural diagram of a hollow guide rod provided by the present application;

[0021] Figure 3 is a structural diagram of an oiling tank provided by Comparative Example 5.

[0022] REFERENCE SIGNS

[0023] 1, oiling device 01, shell 1-1, oiling area

[0024] 1-2, overflow area 1-3, partition 1-4, hollow guide rod

[0025] 1-5, cooling part 1-6, oil pipe inlet 1-7, oil return pipe

[0026] 2, oil tank 21, guide rod 22, tow DETAILED DESCRIPTION

[0027] The endpoints of the ranges and any values disclosed herein are not limited to the precise values recited as the exact dimensions are not critical to the present application. Any numeric range recited is intended to include all values from the lower value to the upper value, inclusive of both values, and to also disclose all values individually. For numerical ranges having an upper and / or lower limit, the range includes each integer within the range, and also includes each non-integer value within the range.

[0028] In the present application, unless otherwise specified, the "top" of the container refers to the 0-10% position from top to bottom of the container; the "upper part" of the container refers to the 10-40% position from top to bottom of the container; the "middle part" of the container refers to the 40-60% position from top to bottom of the container; the "lower part" of the container refers to the 70-90% position from top to bottom of the container; and the "bottom" of the container refers to the 90-100% position from top to bottom of the container.

[0029] The first aspect of the present application provides a structural diagram of an oiling device as shown in Figures 1-2 Figures 1-2 ​It is known that the oiling device includes: a housing 01, an oiling area 1-1 is provided inside the housing, and the oiling area 1-1 is provided with 3 hollow guide rods 1-4. Each hollow guide rod 1-4 is provided with a spray hole, and the included angle θ of the spray hole along the lower part of the vertical line is 20-45°, so that the sprayed oil is sprayed onto the filament bundle located below the hollow guide rod;

[0030] In this configuration, according to the direction of the filament bundle, the first hollow guide rod is higher than the second hollow guide rod, and the horizontal angle α is less than or equal to 15°. The second and third hollow guide rods are at the same height.

[0031] Each hollow guide rod is provided with a cooling component 1-5 below it, and the vertical distance between the cooling component 1-5 and the filament bundle is ≥10mm.

[0032] In this invention, unless otherwise specified, the angle θ between the nozzle and the vertical line is 20-45°, which means that the center line of the nozzle of the hollow guide rod and the vertical line are 20-45°.

[0033] In this invention, unless otherwise specified, the term "the filament bundle is located below the hollow guide rod" means that the filament bundle runs close to the lower part of the hollow guide rod.

[0034] In some embodiments of the present invention, preferably, such as Figure 1 As shown, according to the direction of the filament bundle, the first hollow guide bar is higher than the second hollow guide bar, and the horizontal angle α ≤ 15°, preferably 12° ≤ α ≤ 15°. Adopting the preferred conditions is more conducive to uniform oiling of the raw filament and reducing the accumulation of fuzz.

[0035] In some embodiments of the present invention, preferably, such as Figure 1 As shown, the vertical distance from the cooling components 1-5 to the filament bundle is ≥10mm, preferably 10-15mm. Using these preferred conditions ensures a more uniform temperature of the oil around the fibers, improving the oiling effect.

[0036] In some embodiments of the present invention, preferably, such as Figure 1 As shown, a partition 1-3 parallel to the center line of the housing 01 is also provided inside the housing 01. The partition 1-3 connects the bottom and side wall of the housing 01, but does not connect to the top of the housing 01.

[0037] In some embodiments of the present invention, preferably, such as Figure 1As shown, the partition plate 1-3 divides the shell 01 into an oiling area 1-1 and an overflow area 1-2. In the present application, the oiling area is used for the tows to be immersed in oiling agent, and the oiling agent sprayed from the spray holes of the hollow guide rod is used for secondary oiling; the overflow area is used for recycling the overflowed oiling agent.

[0038] In some embodiments of the present application, preferably, the height ratio of the partition plate 1-3 to the shell 01 is 0.7-0.8:1, for example, 0.7:1, 0.75:1, 0.8:1, and any value in the range consisting of any two of the numerical values. Figure 1 As shown, the height ratio of the partition plate 1-3 to the shell 01 is 0.7-0.8:1, for example, 0.7:1, 0.75:1, 0.8:1, and any value in the range consisting of any two of the numerical values. With the preferred height ratio, the uniformity of the oiling of the original filaments and the reduction of the accumulation of broken filaments are more favorable.

[0039] In some embodiments of the present application, preferably, the length ratio of the oiling area 1-1 to the overflow area 1-2 in the horizontal plane is 10-11:1, for example, 10:1, 10.5:1, 11:1, and any value in the range consisting of any two of the numerical values. Figure 1

[0040] In some embodiments of the present application, preferably, the length ratio of the oiling area 1-1 to the overflow area 1-2 in the horizontal plane is 10-11:1, for example, 10:1, 10.5:1, 11:1, and any value in the range consisting of any two of the numerical values. Figure 1 As shown, the bottom of the oiling area 1-1 is provided with an oiling agent inlet pipe 1-6 for injecting oiling agent into the oiling area; the bottom of the overflow area 1-2 is provided with an oiling agent return pipe 1-7 for guiding the overflowed oiling agent out and recycling it for use in the oiling area.

[0041] In some embodiments of the present application, preferably, the surface roughness Ra of the hollow guide rod 1-4 is ≤0.6 μm, for example, 0.2 μm, 0.4 μm, 0.6 μm, and any value in the range consisting of any two of the numerical values. With the preferred condition, the accumulation of broken filaments in the oiling area and the broken filaments caused thereby are more effectively reduced. In the present application, the surface roughness Ra parameter adopts the evaluation standard GB / T 3505-2000, the symbol standard GB / T 131-1993, and the numerical value standard GB / T 1031-1995.

[0042] In some embodiments of the present application, preferably, the ratio of the diameter of the hollow guide rod 1-4 to the width of the tow 1-8 is 1.5-2:1, for example, 1.5:1, 1.8:1, 2:1, and any value in the range consisting of any two of the numerical values. In this way, the oiling agent sprayed from the spray holes is in full and uniform contact with the tow, improving the uniformity of the oiling.

[0043] In some embodiments of the present application, preferably, the cross section of the spray hole is a regular shape, preferably a rectangle and / or a square, and more preferably a rectangle. In this way, the accumulation of broken filaments in the oiling area and the broken filaments caused thereby are further reduced. ​

[0044] In some embodiments of the present application, preferably, the ratio of the length of the orifice to the width of the fiber in the tow is 0.5-0.8:1, for example, 0.5:1, 0.6:1, 0.8:1, and any value in the range between any two of the values; the width of the orifice is 1-3 mm, for example, 1 mm, 2 mm, 3 mm, and any value in the range between any two of the values.

[0045] In the present application, the type of the tow has a relatively fast selection range. Preferably, the tow is selected from fiber precursors, preferably from carbon fiber precursors, more preferably from polyacrylonitrile-based carbon fiber precursors.

[0046] The second aspect of the present application provides an application of the oiling device of the first aspect in oiling fiber precursors, preferably in oiling carbon fiber precursors, more preferably in oiling polyacrylonitrile-based carbon fiber precursors.

[0047] The third aspect of the present application provides an oiling method of polyacrylonitrile-based carbon fiber precursors, which is carried out in the oiling device of the first aspect, wherein the oiling method comprises: immersing the polyacrylonitrile-based carbon fiber precursors in the oiling zone in the presence of the cooling medium in the cooling component, and performing secondary oiling with the oil agent sprayed through the orifice of the hollow godet.

[0048] In some embodiments of the present application, preferably, the number of the polyacrylonitrile-based carbon fiber precursors in each tow is 3000-12000.

[0049] In some embodiments of the present application, preferably, the running speed of the polyacrylonitrile-based carbon fiber precursors is 5-40 m / min, for example, 5 m / min, 10 m / min, 15 m / min, 20 m / min, 30 m / min, 40 m / min, and any value in the range between any two of the values.

[0050] In some embodiments of the present application, preferably, the ratio of the spraying speed of the oil agent to the running speed of the polyacrylonitrile-based carbon fiber precursors is 0.3-0.5:1, for example, 0.3:1, 0.4:1, 0.5:1, and any value in the range between any two of the values.

[0051] In some embodiments of the present application, preferably, the spraying speed of the oil agent of the hollow godet gradually decreases in the direction of the tow running. Further preferably, the spraying speed of the oil agent of the first, second, and third hollow godets is 5 m / min, 4.7 m / min, and 4.6 m / min, respectively, in the direction of the tow running.

[0052] In some embodiments of the present application, preferably, the flow rate of the cooling medium in the cooling component gradually decreases along the running direction of the fiber bundle. Further preferably, the flow rate of the cooling medium in the first cooling component, the second cooling component and the third cooling component is in the ratio of 1:0.8:0.7 along the running direction of the fiber bundle.

[0053] In some embodiments of the present application, preferably, the oiling method further comprises: recycling the oiling agent discharged from the oiling agent backflow pipe of the overflow area as the circulating oiling agent for the oiling area.

[0054] According to a particularly preferred embodiment of the present application, an oiling device comprises: a housing, wherein an oiling area is arranged, and the oiling area is provided with three hollow godets connected by a groove, each of the hollow godets is provided with a spray hole, and the spray hole has an angle θ of 20-45° below the vertical line, so that the sprayed oiling agent is sprayed to the fiber bundle below the hollow godet;

[0055] wherein, along the running direction of the fiber bundle, the first hollow godet is higher than the second hollow godet, and the horizontal angle α is ≤15°, and the second hollow godet and the third hollow godet are at the same height;

[0056] wherein, below each of the hollow godets, a cooling component is arranged, and the vertical distance from the cooling component to the fiber bundle is ≥10 mm;

[0057] wherein, the surface roughness Ra of the hollow godet is ≤0.6 μm; and the ratio of the diameter of the hollow godet to the width of the fiber bundle is 1.5-2:1;

[0058] wherein, the cross section of the spray hole is rectangular, the ratio of the length of the spray hole to the width of the fiber bundle is 0.5-0.8:1; and the width of the spray hole is 1-3 mm.

[0059] The present application will be described in detail below through examples.

[0060] Preparation of raw fiber before oiling: wet spinning is used to prepare the as-spun fiber, the solid content of the PAN / DMSO stock solution used is 16 wt%, the spinning dope is accurately metered by a metering pump, filtered again, and then wet spinning is used, the spinneret aperture is 60 μm, the number of spinneret holes is 12000, the coagulation temperature is 30℃, the coagulation bath DMSO concentration is 50%, and subsequent two-stage coagulation drafting is performed, the drafting ratios are 1.0 and 1.05 respectively, to obtain a coagulation fiber; the coagulation fiber is subjected to four-stage hot water drafting in hot water at 80-95℃, the total drafting ratio is 5 times, to obtain a hot water drafted fiber; the hot water drafted fiber is washed at 70℃, the washing process is not drafted, to obtain the raw fiber before oiling, i.e. the washed fiber.

[0061] Example 1

[0062] (1) Oiling device such as Figures 1-2 As shown, the oiling device includes: a housing 01, which contains an oiling zone 1-1, a partition 1-3, and an overflow zone 1-2; the oiling zone 1-1 is provided with 3 hollow guide rods and 3 cooling components 1-5, each hollow guide rod is provided with a spray hole, and the included angle θ of the spray hole along the lower part of the vertical line is 20°; an oil inlet pipe 1-6 is provided at the bottom of the oiling zone 1-1, and an oil return pipe 1-7 is provided at the bottom of the overflow zone 1-2;

[0063] In this configuration, the first hollow guide rod is higher than the second hollow guide rod in the direction of filament bundle movement, with a horizontal angle α of 15°. The second and third hollow guide rods are at the same height. The vertical distance from the cooling component to the filament bundle is 10 mm. The surface roughness Ra of each hollow guide rod is 0.6 μm, and its diameter is 40 mm.

[0064] The height ratio of the partition to the shell is 0.75:1; the length ratio of the oiling area to the overflow area in the horizontal plane is 10:1; the nozzle is rectangular, and the ratio of the length of the nozzle to the width of the filament bundle is 0.6:1; the width of the nozzle is 2mm.

[0065] (2) Oiling method, which is carried out in the above-mentioned oiling device, includes: immersing the above-mentioned washed fibers in the oiling area in the presence of cooling water, and performing secondary oiling with the oil sprayed through the nozzle of the hollow guide rod.

[0066] The width of the washed fiber is 20 mm, and the running speed is 15 m / min. According to the direction of fiber bundle operation, the spraying speeds of the oil in the three hollow guide rods are 5 m / min, 4.7 m / min, and 4.6 m / min, respectively. The flow rate ratio of the cooling water in the three cooling media is 1:0.8:0.7.

[0067] After being oiled by an oiling device and pressed by a pressure roller, the fibers were randomly divided into 20 portions. The 20 portions of fibers were then dried at a constant temperature of 150℃ for 5 minutes. The oil content of the 20 portions of fibers was then determined using the method FZ / T 50043-2018. The coefficient of variation of the oil content was 5%, the number of fuzzy fibers per 10,000m was 11, and the frequency of fiber breakage caused by fuzzy fibers was 19 days / time.

[0068] Example 2

[0069] The oiling device according to Example 1 is different in that...

[0070] According to the direction of the filament bundle, the first hollow guide rod is higher than the second hollow guide rod, and the horizontal angle α is 10°.

[0071] The oiling method according to Example 1 was used.

[0072] The fibers after being treated by the oiling device and being pressed by the press roller were randomly divided into 20 parts, and then the 20 parts of fibers were dried at 150℃ for 5min, and then the oil content of the 20 parts of fibers was determined by the method of FZ / T 50043-2018, the variation coefficient of the oil content was 6%, the number of hairiness per 10000m was 13, and the frequency of broken filament caused by hairiness was 15 days / time.

[0073] Example 3

[0074] The oiling device according to Example 1 was used, except that,

[0075] According to the running direction of the filament bundle, the included angle θ of the spray hole along the lower side of the vertical line was 45°.

[0076] The oiling method according to Example 1 was used.

[0077] The fibers after being treated by the oiling device and being pressed by the press roller were randomly divided into 20 parts, and then the 20 parts of fibers were dried at 150℃ for 5min, and then the oil content of the 20 parts of fibers was determined by the method of FZ / T 50043-2018, the variation coefficient of the oil content was 5%, the number of hairiness per 10000m was 12, and the frequency of broken filament caused by hairiness was 18 days / time.

[0078] Example 4

[0079] The oiling device according to Example 1 was used, except that,

[0080] According to the running direction of the filament bundle, the first hollow guide rod was higher than the second hollow guide rod, and the horizontal included angle α was 12°.

[0081] The oiling method according to Example 1 was used.

[0082] The fibers after being treated by the oiling device and being pressed by the press roller were randomly divided into 20 parts, and then the 20 parts of fibers were dried at 150℃ for 5min, and then the oil content of the 20 parts of fibers was determined by the method of FZ / T 50043-2018, the variation coefficient of the oil content was 3%, the number of hairiness per 10000m was 9, and the frequency of broken filament caused by hairiness was 20 days / time.

[0083] Example 5

[0084] The oiling device according to Example 1 was used, except that,

[0085] According to the running direction of the filament bundle, the first hollow guide rod was higher than the second hollow guide rod, and the horizontal included angle α was 10°.

[0086] The included angle θ of the spray hole along the lower side of the vertical line was 25°.

[0087] The vertical distance from the cooling component to the fiber bundle was 15 mm.

[0088] The oiling method of Example 1 was followed.

[0089] The fibers after being pressed by the press roller after being oiled by the oiling device were randomly divided into 20 portions, and then the 20 portions of fibers were dried at 150°C for 5 min, and then the oil content of the 20 portions of fibers was determined by the method of FZ / T 50043-2018, the coefficient of variation of the oil content was 7%, the number of hair filaments per 10000 m was 14, and the frequency of broken filaments caused by hair filaments was 14 days / time.

[0090] Example 6

[0091] The oiling device of Example 1 was followed.

[0092] The oiling method of Example 1 was followed, except that,

[0093] The oiling speed of the oil agent of the 3 hollow guide rods was 5 m / min.

[0094] The fibers after being pressed by the press roller after being oiled by the oiling device were randomly divided into 20 portions, and then the 20 portions of fibers were dried at 150°C for 5 min, and then the oil content of the 20 portions of fibers was determined by the method of FZ / T 50043-2018, the coefficient of variation of the oil content was 10%, the number of hair filaments per 10000 m was 15, and the frequency of broken filaments caused by hair filaments was 12 days / time.

[0095] Example 7

[0096] The oiling device of Example 1 was followed.

[0097] The oiling method of Example 1 was followed, except that,

[0098] The flow rates of the cooling water of the 3 cooling media were the same.

[0099] The fibers after being pressed by the press roller after being oiled by the oiling device were randomly divided into 20 portions, and then the 20 portions of fibers were dried at 150°C for 5 min, and then the oil content of the 20 portions of fibers was determined by the method of FZ / T 50043-2018, the coefficient of variation of the oil content was 8%, the number of hair filaments per 10000 m was 20, and the frequency of broken filaments caused by hair filaments was 10 days / time.

[0100] Comparative Example 1

[0101] The oiling device of Example 1 was followed, except that,

[0102] According to the running direction of the fiber bundle, the first hollow guide rod was higher than the second hollow guide rod, and the horizontal included angle a was 20°.

[0103] The oiling method according to Example 1.

[0104] The fibers after being treated by the oiling device and being pressed by the press roller were randomly divided into 20 portions, and then the 20 portions of fibers were dried at 150°C for 5 min, and then the oil content of the 20 portions of fibers was determined by the method of FZ / T 50043-2018. The coefficient of variation of the oil content was 10%, the number of hairiness per 10000 m was 20, and the frequency of broken ends caused by hairiness was 12 days / time.

[0105] Comparative Example 2

[0106] The oiling device according to Example 1, except that,

[0107] The included angle θ of the spray hole downward along the vertical line was 10°.

[0108] The oiling method according to Example 1.

[0109] The fibers after being treated by the oiling device and being pressed by the press roller were randomly divided into 20 portions, and then the 20 portions of fibers were dried at 150°C for 5 min, and then the oil content of the 20 portions of fibers was determined by the method of FZ / T 50043-2018. The coefficient of variation of the oil content was 12%, the number of hairiness per 10000 m was 22, and the frequency of broken ends caused by hairiness was 11 days / time.

[0110] Comparative Example 3

[0111] The oiling device according to Example 1, except that,

[0112] The vertical distance from the cooling part to the fiber bundle was 8 mm.

[0113] The oiling method according to Example 1.

[0114] The fibers after being treated by the oiling device and being pressed by the press roller were randomly divided into 20 portions, and then the 20 portions of fibers were dried at 150°C for 5 min, and then the oil content of the 20 portions of fibers was determined by the method of FZ / T 50043-2018. The coefficient of variation of the oil content was 12%, the number of hairiness per 10000 m was 25, and the frequency of broken ends caused by hairiness was 11 days / time.

[0115] Comparative Example 4

[0116] The oiling device according to Example 1, except that,

[0117] According to the running direction of the fiber bundle, the first hollow guide rod was higher than the second hollow guide rod, and the horizontal included angle a was 20°.

[0118] The included angle θ of the spray hole downward along the vertical line was 50°.

[0119] The vertical distance from the cooling component to the tow was 5 mm.

[0120] The oiling method of Example 1 was followed.

[0121] The fibers after being pressed by the press roller were randomly divided into 20 portions, and then the 20 portions of fibers were dried at 150°C for 5 min, and then the oil content of the 20 portions of fibers was determined by the method of FZ / T 50043-2018, the coefficient of variation of the oil content was 15%, the number of hair yarns per 10000 m was 30, and the frequency of yarn breakage caused by hair yarns was 10 days / time.

[0122] Comparative Example 5

[0123] The oiling tank shown in Figure 3 was used for oiling treatment, the fiber width was 20 mm, the running speed of the tow in the tank was 15 m / min, there were two solid guide rods in the tank, the surface roughness Ra of the guide rod was 0.6 μm, and the diameter of the guide rod was 40 mm.

[0124] The fibers after being pressed by the press roller were randomly divided into 20 portions, and then the 20 portions of fibers were dried at 150°C for 5 min, and then the oil content of the 20 portions of fibers was determined by the method of FZ / T 50043-2018, the coefficient of variation of the oil content was 20%, the number of hair yarns per 10000 m was 40, and the frequency of yarn breakage caused by hair yarns was 6 days / time.

[0125] Compared with Comparative Examples 1-5, the oiling of the polyacrylonitrile-based carbon fiber precursor by the oiling device provided by the present application in Examples 1-7 effectively improves the uniformity of oiling and effectively reduces the accumulation of hair yarns in the oiling device and the yarn breakage caused thereby.

[0126] The preferred embodiments of the present application are described in detail above, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be considered as disclosed by the present application and fall within the protection scope of the present application.

Claims

1. An oiling device, characterized in that, The oiling device includes: a housing (01), an oiling area (1-1) is provided inside the housing (01), and three hollow guide rods (1-4) are provided in the oiling area (1-1). Each hollow guide rod (1-4) is provided with a spray hole, and the angle θ between the center line of the spray hole and the vertical line is 20-45°, so that the sprayed oil is sprayed onto the filament bundle located below the hollow guide rod. In this configuration, according to the direction of the filament bundle, the first hollow guide rod is higher than the second hollow guide rod, and the horizontal included angle α ≤ 15°, while the second and third hollow guide rods are at the same height. Each of the hollow guide rods (1-4) is provided with a cooling component (1-5) below it, and the vertical distance between the cooling component (1-5) and the wire bundle is ≥10mm.

2. The oiling device according to claim 1, wherein, The housing (01) is also provided with a partition (1-3) parallel to the center line of the housing (01). The partition (1-3) connects the bottom and side wall of the housing (01) but does not connect to the top of the housing (01).

3. The oiling device according to claim 2, wherein, The partition (1-3) divides the interior of the housing (01) into an oiling zone (1-1) and an overflow zone (1-2).

4. The oiling device according to claim 2, wherein, The height ratio of the partition (1-3) to the shell (01) is 0.7-0.8:

1.

5. The oiling device according to claim 3, wherein, The length ratio of the oiling zone (1-1) and the overflow zone (1-2) in the horizontal plane is 10-11:

1.

6. The oiling device according to claim 3, wherein, The bottom of the oiling zone (1-1) is provided with an oil inlet pipe (1-6), and the bottom of the overflow zone (1-2) is provided with an oil return pipe (1-7).

7. The oiling device according to any one of claims 1-6, wherein, The surface roughness Ra of the hollow guide wire rod (1-4) is ≤0.6µm.

8. The oiling device according to claim 7, wherein, The ratio of the diameter of the hollow guide rod (1-4) to the width of the wire bundle is 1.5-2:

1.

9. The oiling device according to any one of claims 1-6, wherein, The cross-section of the nozzle is a regular shape.

10. The oiling device according to claim 9, wherein, The cross-section of the nozzle is rectangular and / or square.

11. The oiling device according to claim 9, wherein, The ratio of the length of the nozzle to the width of the filament bundle is 0.5-0.8:1; the width of the nozzle is 1-3mm.

12. The application of the oiling device according to any one of claims 1-11 in the oiling of fiber raw yarn.

13. The application according to claim 12, wherein, The application of the oiling device in oiling carbon fiber precursor.

14. The application according to claim 13, wherein, The application of the oiling device in the oiling of polyacrylonitrile-based carbon fiber precursor.

15. A method for oiling polyacrylonitrile-based carbon fiber precursor, characterized in that, The oiling method is performed in the oiling apparatus according to any one of claims 1-11, wherein the oiling method includes: impregnating polyacrylonitrile-based carbon fiber precursors in the oiling zone with oil in the presence of a cooling medium in a cooling component, and performing secondary oiling with oil sprayed through the nozzle of a hollow guide rod.

16. The oiling method according to claim 15, wherein, Each bundle of the aforementioned polyacrylonitrile-based carbon fiber precursor contains 3,000-12,000 fibers.

17. The oiling method according to claim 16, wherein, The running speed of the polyacrylonitrile-based carbon fiber precursor is 5-40 m / min.

18. The oiling method according to any one of claims 15-17, wherein, The ratio of the spraying speed of the oil to the running speed of the polyacrylonitrile-based carbon fiber precursor is 0.3-0.5:

1.

19. The oiling method according to claim 18, wherein the spraying speed of the oil from the hollow guide rod gradually decreases according to the direction of the filament bundle running.

20. The oiling method according to claim 19, wherein the flow rate of the cooling medium in the cooling component gradually decreases according to the direction of the filament bundle running.

21. The oiling method according to claim 15, wherein, The oiling method further includes: recycling the oil discharged through the oil return pipe of the overflow area as a circulating oil for use in the oiling area.

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