A central distributor structure of a pre-oxidation furnace and a method for adjusting its height

Abstract

The present invention relates to the technical field of carbon fiber production, and in particular to a central distributor structure of a pre-oxidation furnace and a height adjustment method thereof, comprising: a first box and a second box arranged at intervals along the wire running direction, the first box and the second box are respectively provided with a plurality of air outlets at both ends of the wire running direction; wherein the first box and the second box together form a concave structure at the top end in the vertical direction, and the concave structure is lower in the middle height along the wire running direction than at the two ends; the first box and the second box include a plurality of them, and are arranged at intervals along the vertical direction. In the present invention, a common concave structure is formed at the top end in the vertical direction, and this structure makes the central distributor present a lower height in the middle part of the wire running direction, reduces the contact between the filament bundle and the central distributor, reduces the occurrence of wire rubbing, and thus improves the production efficiency and quality of carbon fiber.

Description

Technical Field

[0001] The invention relates to the technical field of carbon fiber production, and in particular to a central distributor structure of a pre-oxidation furnace and a height adjustment method thereof. Background Art

[0002] In the preparation of carbon fiber, the preoxidation furnace is an important equipment in the production process of carbon fiber. The preoxidation furnace uses the driving roller to continuously preoxidize the carbon fiber raw fiber bundle in the preoxidation furnace. After being baked at different gradient temperatures in several preoxidation furnaces, oxidized fibers and preoxidized fibers are formed. The preoxidized fibers are then carbonized in medium-temperature and high-temperature carbonization furnaces.

[0003] During the pre-oxidation process, the tension of the filament bundle can be controlled by the transmission speed of the driving roller. Although the filament bundle is exerted with a certain tension by the driving roller, the filament bundle will still contact with the central distributor in the pre-oxidation furnace due to its own weight and cause "filament rubbing". This filament rubbing phenomenon makes the filament bundle vulnerable to damage and affects the performance of the final carbon fiber.

[0004] The information disclosed in this background technology section is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to those skilled in the art. Summary of the invention

[0005] The present invention provides a central distributor structure of a pre-oxidation furnace and a height adjustment method thereof, thereby effectively solving the problems in the background technology.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: a central distributor structure of a pre-oxidation furnace, comprising:

[0007] A first box and a second box are arranged at intervals along the wire running direction, and a plurality of air outlets are respectively arranged at both ends of the first box and the second box in the wire running direction;

[0008] The first box and the second box together form a concave structure at the top in the vertical direction, and the middle height of the concave structure along the wire running direction is lower than the height at both ends;

[0009] The first box and the second box include a plurality of first boxes and the second boxes are arranged at intervals in the vertical direction.

[0010] Furthermore, the first box body includes a first cavity and a second cavity that are not connected to each other, the second box body includes a third cavity and a fourth cavity that are not connected to each other, the first box body and the second box body are symmetrically arranged, the second cavity and the third cavity are located in the middle of the wire running direction, and the top height thereof is lower than the height of the first cavity and the fourth cavity at both ends in the wire running direction.

[0011] Furthermore, the concave structure comprises:

[0012] A first arc and a second arc are arranged on a vertical section parallel to the wire running direction, wherein the first arc is arranged at the top of the first box body, and the second arc is arranged at the top of the second box body, and the first arc and the second arc form a parabola.

[0013] Furthermore, the concave structure comprises:

[0014] A first oblique line and a second oblique line are arranged on a vertical section parallel to the wire running direction, wherein the first oblique line is arranged at the top of the first box body, and the second oblique line is arranged at the top of the second box body, and the angle between the first oblique line and the second oblique line is an obtuse angle.

[0015] Furthermore, the concave structure comprises:

[0016] The third arc and the fourth arc are arranged on a vertical section parallel to the wire running direction, the third arc is arranged at the top of the first cavity, the fourth arc is arranged at the top of the fourth cavity, and the tops of the second cavity and the third cavity are horizontal planes.

[0017] Furthermore, the concave structure comprises:

[0018] The third oblique line and the fourth oblique line are arranged on the vertical section parallel to the wire running direction, the third oblique line is arranged at the top of the first cavity, the fourth oblique line is arranged at the top of the fourth cavity, and the tops of the second cavity and the third cavity are horizontal planes.

[0019] Furthermore, the concave structure comprises:

[0020] The fifth oblique line, the sixth oblique line, the seventh oblique line and the eighth oblique line arranged on the vertical section parallel to the wire feeding direction are respectively arranged at the top of the first cavity, the second cavity, the third cavity and the fourth cavity, and the angle between the fifth oblique line and the eighth oblique line is smaller than the angle between the sixth oblique line and the seventh oblique line.

[0021] The present invention also includes a method for adjusting the height of a central distributor of a pre-oxidation furnace, and adjusting the central distributor structure as described above includes the following steps:

[0022] Collect the wire running length between the driving rollers and the mass of the wire bundle per unit length;

[0023] The tension provided by the driving roller is collected, and the deadweight of the tow between the driving rollers is calculated based on the force analysis;

[0024] Calculate the angle between the tow and the horizontal direction due to its own weight, and calculate the falling height of the tow;

[0025] Determine the height between the layers of the central distributor and adjust the height of the central distributor.

[0026] Further, determining the height between layers of the central distributor includes:

[0027] According to the falling height of the tow, the distance between the bottom surface of the first box and the second box of the upper layer in the central distributor and the lowest point of the concave structure of the first box and the second box of the lower layer is set to be greater than the falling height.

[0028] Further, the calculation of the falling height of the tow includes:

[0029] The collected wire length between the driving rollers is L, and the mass of the wire bundle per unit length is m1. Assuming that the wire bundle forms an angle θ with the horizontal due to its own weight, the mass of the wire between the driving rollers is:

[0030]

[0031] The weight of the tow G is:

[0032]

[0033] The driving roller provides the required tension F of the carbon fiber tow. According to the force analysis, it can be obtained that:

[0034]

[0035] From the above formula we can get:

[0036]

[0037] According to the geometric relationship, the falling height h of the tow can be obtained:

[0038]

[0039] In order to ensure that the carbon fiber tow does not rub against the central distributor, the interlayer height h of the central distributor is required. 层 satisfy:

[0040]

[0041] The beneficial effects of the present invention are as follows: the first box body and the second box body in the present invention are arranged along the wire running direction, and a common concave structure is formed at the top in the vertical direction. This structure makes the central distributor present a lower height in the middle part of the wire running direction, while the heights at both ends are relatively high. This structure helps to reduce the contact between the yarn bundle and the central distributor, and reduce the occurrence of wire friction, thereby improving the production efficiency and quality of carbon fiber. At the same time, because the wire running space becomes larger, the air flow speed entering the wire running space from the upper and lower air outlets slows down, thereby reducing the disturbance of the yarn bundle and reducing the risk of wire friction between the yarn bundle and the central distributor. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0043] Figure 1 It is a structural diagram of the central distributor;

[0044] Figure 2 This is a schematic diagram of the airflow direction of the central distributor;

[0045] Figures 3 to 7 Schematic diagrams of structures of different forms of concave structures;

[0046] Figure 8 Force analysis diagram for calculating the falling height of the tow. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0048] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by “center”, “up”, “down”, “left”, “right”, “vertical”, “horizontal”, “inside” and “outside”, etc., are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0049] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] like Figures 1 to 2 Shown: A central distributor structure of a pre-oxidation furnace, comprising:

[0051] A first box body 1 and a second box body 2 are arranged at intervals along the wire running direction, and a plurality of air outlets 3 are respectively arranged at both ends of the first box body 1 and the second box body 2 in the wire running direction;

[0052] The first box body 1 and the second box body 2 together form a concave structure A at the top in the vertical direction, and the middle height of the concave structure A along the wire running direction is lower than the height at both ends;

[0053] The first box body 1 and the second box body 2 include a plurality of first boxes 1 and second boxes 2, which are arranged at intervals in the vertical direction.

[0054] By arranging the first box body 1 and the second box body 2 along the wire running direction and forming a common concave structure A at the top in the vertical direction, this structure makes the central distributor present a lower height in the middle part of the wire running direction, while the heights at both ends are relatively high. This structure helps to reduce the contact between the tow and the central distributor, reduce the occurrence of wire rubbing, and thus improve the production efficiency and quality of carbon fiber. Figure 2 As shown, the arrow in the figure indicates the flow direction of the outlet airflow. As the wire feeding space becomes larger, the airflow speed entering the wire feeding space from the upper and lower air outlets 3 slows down, thereby reducing the disturbance to the wire bundle and reducing the risk of the wire bundle rubbing against the central distributor.

[0055] In this embodiment, the first box body 1 includes a first cavity 11 and a second cavity 12 which are not connected to each other, and the second box body 2 includes a third cavity 21 and a fourth cavity 22 which are not connected to each other. The first box body 1 and the second box body 2 are symmetrically arranged, and the second cavity 12 and the third cavity 21 are located in the middle of the wire feeding direction, and the top height thereof is lower than the height of the first cavity 11 and the fourth cavity 22 at both ends in the wire feeding direction.

[0056] The first box 1 and the second box 2 are symmetrically arranged in the pre-oxidation furnace. This symmetry helps to ensure uniform airflow distribution, thereby improving the working efficiency of the pre-oxidation furnace and the quality of carbon fiber. The second cavity 12 and the third cavity 21 are located in the middle of the wire running direction, and the height of their top ends is lower than the height of the first cavity 11 and the fourth cavity 22 at both ends of the wire running direction. This setting makes the height of the central cavity lower than the cavities on both sides, thereby forming a concave structure, which helps to reduce the contact between the filament bundle and the central distributor and reduce the occurrence of wire rubbing. While ensuring symmetry, the central distributor structure of the pre-oxidation furnace further optimizes the concave structure, effectively reduces the risk of wire rubbing, and improves the stability and quality of the carbon fiber production process.

[0057] like Figure 3 As shown, the concave structure A includes:

[0058] The first arc A1 and the second arc A2 are arranged on a vertical section parallel to the wire running direction. The first arc A1 is arranged at the top of the first box 1, and the second arc A2 is arranged at the top of the second box 2. The first arc A1 and the second arc A2 form a parabola.

[0059] Through this design, the concave structure A forms a smooth curve, allowing the filament bundle to move more smoothly when passing through the pre-oxidation furnace and reducing the contact with the central distributor, further reducing the risk of rubbing and improving the stability and quality of the carbon fiber production process.

[0060] Or Figure 4 As shown, the concave structure A includes:

[0061] The first oblique line Aa and the second oblique line Ab are set on the vertical section parallel to the wire running direction. The first oblique line Aa is set at the top of the first box 1, and the second oblique line Ab is set at the top of the second box 2. The angle between the first oblique line Aa and the second oblique line Ab is an obtuse angle.

[0062] The angle between the first oblique line Aa and the second oblique line Ab is an obtuse angle. This obtuse angle makes the concave structure A form an inwardly inclined shape, which helps to reduce the contact area between the tow and the central distributor, and further reduces the risk of rubbing. Through this design, the concave structure A forms an inwardly inclined angle, which makes the tow move more smoothly when passing through the pre-oxidation furnace, and reduces the contact between the tow and the central distributor, further reducing the risk of rubbing, and improving the stability and quality of the carbon fiber production process.

[0063] Or as Figure 5 As shown, the concave structure A may include:

[0064] The third arc A3 and the fourth arc A4 are set on the vertical section parallel to the wire running direction. The third arc A3 is set at the top of the first cavity 11, and the fourth arc A4 is set at the top of the fourth cavity 22. The tops of the second cavity 12 and the third cavity 21 are horizontal planes.

[0065] The tops of the second cavity 12 and the third cavity 21 form a horizontal plane. This design forms a concave structure between the third arc A3 and the fourth arc A4, which helps to reduce the contact area between the tow and the central distributor and reduce the risk of scratching.

[0066] Through this design, the concave structure A forms an inwardly concave shape, which allows the filament bundle to move more smoothly when passing through the pre-oxidation furnace and reduces the contact with the central distributor, further reducing the risk of rubbing and improving the stability and quality of the carbon fiber production process.

[0067] It is also possible that Figure 6 As shown, the concave structure A may include:

[0068] The third oblique line Ac and the fourth oblique line Ad are set on the vertical section parallel to the wire running direction. The third oblique line Ac is set at the top of the first cavity 11, and the fourth oblique line Ad is set at the top of the fourth cavity 22. The tops of the second cavity 12 and the third cavity 21 are horizontal planes.

[0069] The top ends of the second cavity 12 and the third cavity 21 form a horizontal plane. This design allows a concave structure to be formed between the third oblique line Ac and the fourth oblique line Ad, which helps to reduce the contact area between the yarn bundle and the central distributor and reduce the risk of yarn scratching.

[0070] Through this design, the concave structure A forms an inwardly concave shape, which allows the filament bundle to move more smoothly when passing through the pre-oxidation furnace and reduces the contact with the central distributor, further reducing the risk of rubbing and improving the stability and quality of the carbon fiber production process.

[0071] Finally, if Figure 7 As shown, the concave structure A may include:

[0072] The fifth oblique line Ae, the sixth oblique line Af, the seventh oblique line Ag and the eighth oblique line Ah arranged on the vertical section parallel to the wire feeding direction are respectively arranged at the top of the first cavity 11, the second cavity 12, the third cavity 21 and the fourth cavity 22, and the angle between the fifth oblique line Ae and the eighth oblique line Ah is smaller than the angle between the sixth oblique line Af and the seventh oblique line Ag.

[0073] The angle between the fifth oblique line Ae and the eighth oblique line Ah is smaller than the angle between the sixth oblique line Af and the seventh oblique line Ag. This design allows the concave structure A to form an inwardly inclined shape and a deeper depression in the central position, which helps to reduce the contact area between the wire bundle and the central distributor and reduce the risk of wire scratching.

[0074] Through this design, the concave structure A forms an inwardly inclined concave shape, which allows the filament bundle to move more smoothly when passing through the pre-oxidation furnace and reduces the contact with the central distributor, further reducing the risk of rubbing and improving the stability and quality of the carbon fiber production process.

[0075] This embodiment also includes a method for adjusting the height of the central distributor of the pre-oxidation furnace, and adjusting the central distributor structure as described above includes the following steps:

[0076] Collect the wire running length between the driving rollers and the mass of the wire bundle per unit length;

[0077] The tension provided by the driving roller is collected, and the deadweight of the tow between the driving rollers is calculated based on the force analysis;

[0078] Calculate the angle between the tow and the horizontal direction due to its own weight, and calculate the falling height of the tow;

[0079] Determine the height between the layers of the central distributor and adjust the height of the central distributor.

[0080] After obtaining the self-weight tension of the yarn bundle, the angle between the yarn bundle and the horizontal direction due to its own weight can be calculated based on the principle of force balance, and the falling height of the yarn bundle can be further calculated. This step is to determine the distance the yarn bundle falls, so as to adjust the height of the central distributor.

[0081] According to the falling height of the tow and the preset safety distance, the height between the layers of the central distributor is determined, and the height of the central distributor is adjusted accordingly. This can be done by adjusting the supporting structure of the central distributor or using an automatic adjustment device.

[0082] Through this height adjustment method, the height of the central distributor of the pre-oxidation furnace can be accurately adjusted according to the real-time collected data to ensure the smooth operation of the filament bundle in the pre-oxidation furnace and avoid wire rubbing or other adverse effects.

[0083] Among them, determining the height between the layers of the central distributor includes:

[0084] According to the falling height of the tow, the distance between the bottom surface of the first box 1 and the second box 2 of the upper layer in the central distributor and the lowest point of the concave structure A of the first box 1 and the second box 2 of the lower layer is set to be greater than the falling height.

[0085] Add a safety margin to the falling height of the tow to get the bottom height of the first box 1 and the second box 2 of the upper layer in the central distributor. This height setting needs to ensure that the distance from the lowest point of the concave structure A of the first box 1 and the second box 2 of the next layer is greater than the falling height of the tow to avoid collision or contact between the tow and the structure of the next layer.

[0086] According to the bottom height obtained in the previous step, the height of the central distributor is adjusted accordingly. This may need to be achieved through mechanical means or automatic adjustment devices to ensure that the height difference between the layers meets safety requirements. Through this preferred solution, the height between the layers of the central distributor can be set according to the falling height of the tow, ensuring the safe operation of the tow in the pre-oxidation furnace and avoiding collision or contact with the next layer of structure, thereby improving the efficiency and quality of carbon fiber production.

[0087] like Figure 8 As shown, the calculation of the falling height of the tow includes: the collected wire length between the driving rollers is L, the mass of the tow per unit length is m1, and it is assumed that the tow forms an angle θ with the horizontal due to its own weight, then the mass of the wire between the driving rollers is:

[0088]

[0089] The weight of the tow G is:

[0090]

[0091] The driving roller provides the required tension F of the carbon fiber tow. According to the force analysis, it can be obtained that:

[0092]

[0093] From the above formula we can get:

[0094]

[0095] According to the geometric relationship, the falling height h of the tow can be obtained:

[0096]

[0097] In order to ensure that the carbon fiber tow does not rub against the central distributor, the interlayer height h of the central distributor is required. 层 satisfy:

[0098]

[0099] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A central distributor structure of a pre-oxidation furnace, characterized in that: include: A first box and a second box are arranged at intervals along the wire running direction, and a plurality of air outlets are respectively arranged at both ends of the first box and the second box in the wire running direction; The first box and the second box together form a concave structure at the top in the vertical direction, and the middle height of the concave structure along the wire running direction is lower than the height at both ends; The first box and the second box include a plurality of boxes, which are arranged at intervals in the vertical direction; The first box body includes a first cavity and a second cavity which are not connected to each other, the second box body includes a third cavity and a fourth cavity which are not connected to each other, the first box body and the second box body are symmetrically arranged, the second cavity and the third cavity are located in the middle of the wire running direction, and the top heights thereof are lower than the heights of the first cavity and the fourth cavity at both ends in the wire running direction, so that the airflow speed entering the wire running space is slowed down; The central distributor structure of the pre-oxidation furnace uses the following height adjustment method, including the following steps: Collect the wire running length between the driving rollers and the mass of the wire bundle per unit length; The tension provided by the driving roller is collected, and the deadweight of the tow between the driving rollers is calculated based on the force analysis; Calculate the angle between the tow and the horizontal direction due to its own weight, and calculate the falling height of the tow; Determine the height between the layers of the central distributor and adjust the height of the central distributor; Determining the height between layers of the central distributor includes: According to the falling height of the tow, the distance between the bottom surface of the first box and the second box of the upper layer in the central distributor and the lowest point of the concave structure of the first box and the second box of the lower layer is set to be greater than the falling height; The calculation of the tow drop height comprises: The collected wire length between the driving rollers is L, and the mass of the wire bundle per unit length is m1. Assuming that the wire bundle forms an angle θ with the horizontal due to its own weight, the mass of the wire between the driving rollers is: The weight of the tow G is: The driving roller provides the required tension F of the carbon fiber tow. According to the force analysis, it can be obtained that: From the above formula we can get: According to the geometric relationship, the falling height h of the tow can be obtained: In order to ensure that the carbon fiber tow does not rub against the central distributor, the interlayer height h of the central distributor is required. 层 satisfy:

2. The central distributor structure of the pre-oxidation furnace according to claim 1 is characterized in that: The concave structure comprises: A first arc and a second arc are arranged on a vertical section parallel to the wire running direction, wherein the first arc is arranged at the top of the first box body, and the second arc is arranged at the top of the second box body, and the first arc and the second arc form a parabola.

3. The central distributor structure of the pre-oxidation furnace according to claim 1 is characterized in that: The concave structure comprises: A first oblique line and a second oblique line are arranged on a vertical section parallel to the wire running direction, wherein the first oblique line is arranged at the top of the first box body, and the second oblique line is arranged at the top of the second box body, and the angle between the first oblique line and the second oblique line is an obtuse angle.

4. The central distributor structure of the pre-oxidation furnace according to claim 1 is characterized in that: The concave structure comprises: The third arc and the fourth arc are arranged on a vertical section parallel to the wire running direction, the third arc is arranged at the top of the first cavity, the fourth arc is arranged at the top of the fourth cavity, and the tops of the second cavity and the third cavity are horizontal planes.

5. The central distributor structure of the pre-oxidation furnace according to claim 1, characterized in that: The concave structure comprises: The third oblique line and the fourth oblique line are arranged on the vertical section parallel to the wire running direction, the third oblique line is arranged at the top of the first cavity, the fourth oblique line is arranged at the top of the fourth cavity, and the tops of the second cavity and the third cavity are horizontal planes.

6. The central distributor structure of the pre-oxidation furnace according to claim 1, characterized in that: The concave structure comprises: The fifth oblique line, the sixth oblique line, the seventh oblique line and the eighth oblique line arranged on the vertical section parallel to the wire feeding direction are respectively arranged at the top of the first cavity, the second cavity, the third cavity and the fourth cavity, and the angle between the fifth oblique line and the eighth oblique line is smaller than the angle between the sixth oblique line and the seventh oblique line.

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