A spinning process for producing bending-resistant wide-wing I-beam wire strips

Abstract

The present invention discloses a spinning process for bending-resistant wide-wing I-beam cross-section filaments, comprising the following steps: extruding a melt of a fiber-forming polymer from a spinneret hole of a spinneret through a metering pump to form a liquid stream, and then solidifying the stream in a coagulation bath to form a spun fiber; wherein the spinneret hole comprises a guide hole and a microhole, and the microhole comprises a first hole, a second hole and a third hole connected vertically in sequence, and the first hole, the second hole and the third hole form a wide-wing I-shape in the cross section of the spinning process; during the spinning process, the hole wall of the second hole is continuously cooled so that the web temperature of the spun fiber leaving the spinneret is lower than the wing temperature of the spun fiber, thereby enabling various parts of the spun fiber to be evenly cooled when being air-cooled, thereby solving the problem of different cooling rates in various directions of the spun fiber of the wide-wing I-beam cross-section in the subsequent cooling process.

Description

Technical Field

[0001] The present invention relates to the field of textile spinning, and in particular to a spinning process (spinning method) for bending-resistant wide-wing I-beam cross-section wire strips. Background Art

[0002] After the melt is ejected into a thin stream from the micropores on the spinneret, it gradually cools and takes shape along the path of the filament (referred to as the spinning path). The temperature, diameter, movement speed, force, viscosity and internal structure of each particle on the filament are constantly changing, especially within 1m from the spinneret, where the changes are the greatest. External conditions have a great influence on the uniformity of the filament's fineness, uneven strength and elongation, and post-tensile properties. Therefore, it is very important to control the cooling and blowing solidification conditions.

[0003] In the production of wire rods with wide-wing I-beam sections, the wind blowing toward the web is easily blocked by the wing plates during the annular blowing cooling process, resulting in differences in cooling rates in all directions of the wire rod. The uneven cooling affects the performance of the wire rod. Summary of the Invention

[0004] The object of the present invention is to provide a spinning process (spinning method) for wire strips with a bending-resistant wide-wing I-beam cross-section, so as to solve the problem that during the cooling process of the wide-wing I-beam cross-section, the wind blowing toward the web is easily blocked by the wing plate, resulting in different cooling rates of the wire strips in different directions.

[0005] In order to solve the above technical problems, the present invention specifically provides the following technical solutions:

[0006] A spinning process for bending-resistant wide-wing I-beam cross-section filaments comprises the following steps: extruding a melt of a fiber-forming polymer from a spinneret through a metering pump to form a liquid stream, which is then solidified in a coagulation bath to form spun fibers; wherein the spinneret comprises a guide hole and microholes, the microholes comprising a first hole, a second hole, and a third hole connected vertically in sequence, the first hole, the second hole, and the third hole forming a wide-wing I-shape in the cross section of the spinning process; and continuously cooling the hole wall of the second hole during the spinning process so that the web temperature of the spun fiber leaving the spinneret is lower than the wing temperature of the spun fiber.

[0007] Furthermore, the cross-sectional area of ​​the micropore is 0.12 mm²~0.2 mm², the ratio of the length of the micropore to the length of the diagonal of the micropore is 1.5~2, and the first hole and the third hole are symmetrical with respect to the second hole.

[0008] Furthermore, the widths of the first hole, the second hole, and the third hole are 0.14 mm to 0.18 mm, and the lengths of the first hole, the second hole, and the third hole are 0.85 mm to 1.1 mm.

[0009] Furthermore, the diameter of the entrance of the guide hole is 0.6-0.8 mm.

[0010] Furthermore, a cooling oil channel is formed inside the spinneret, and the inner wall of at least one section of the cooling oil channel is close to the hole wall of the second hole, so that a first heat exchange plate is formed between the cooling oil channel and the second hole, and cooling oil circulates in the cooling oil channel to reduce the temperature of the inner wall of the second hole.

[0011] On the other hand, a heat absorbing side of a heat pump is embedded in the spinneret, and the heat absorbing side of the heat pump is close to the hole wall of the second hole.

[0012] Furthermore, during the spinning process, the hole walls of the first hole and the third hole are continuously heated so that the temperatures of the first hole and the third hole are always constant.

[0013] Furthermore, a heating oil channel is formed inside the spinneret, and the inner wall of at least one section of the heating oil channel is close to the hole walls of the first hole and the third hole, so that a second heat exchange plate is formed between the heating oil channel and the first hole and the third hole, and heating oil circulates in the heating oil channel to maintain the temperature of the inner walls of the first hole and the third hole.

[0014] Furthermore, before heating the fiber-forming polymer, the fiber-forming polymer and the pore-forming agent are mixed. During the spinning process, the pore-forming agent is decomposed by heat to generate gas, so that bubbles and pores are generated on the surface of the nascent fiber.

[0015] Furthermore, the pore-forming agent is NH4HCO3.

[0016] Compared with the prior art, this application has the following beneficial effects:

[0017] Provided is a spinning process for bending-resistant wide-wing I-beam cross-section wire strips. By continuously cooling the hole walls of the webs used to form primary fibers during the spinning process, the web temperature of the primary fibers leaving the spinneret is lower than the wing temperature of the primary fibers. This allows various parts of the primary fibers to be cooled uniformly when air-cooled, thereby solving the problem of different cooling rates in different directions of the primary fibers of the wide-wing I-beam cross-section during the subsequent cooling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other implementation drawings based on the provided drawings without inventive effort.

[0019] Figure 1 is a three-dimensional diagram of a spinneret according to Example 1 of the present invention, showing a multi-hole spinneret;

[0020] Figure 2 This is a three-dimensional diagram of a spinneret according to Example 1 of the present invention, showing a single-hole spinneret;

[0021] Figure 3 Schematic diagram of the spinning direction of the spinneret of Example 1 of the present invention, showing a single-hole spinneret;

[0022] Figure 4 for Figure 3 Cross-sectional view in the AA direction;

[0023] Figure 5 for Figure 3 Cross-sectional view in the BB direction;

[0024] The numbers in the figure represent the following:

[0025] 1-spinneret; 11-first plate; 12-second plate; 13-third plate; 14-groove; 141-annular groove; 142-linear groove;

[0026] 2-spinneret hole; 21-guide hole; 22-microhole; 221-first hole; 222-second hole; 223-third hole;

[0027] 3-cooling oil channel; 31-first heat exchange plate; 32-cooling oil hole;

[0028] 4-heating oil channel; 41-second heat exchange plate; 42-heating oil hole. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] The invention discloses a spinning process for producing bending-resistant wide-wing I-beam cross-section wire strips.

[0031] The following provides Example 1 to solve the problem that during the cooling process of the wide-wing I-beam section, the wind blowing toward the web is easily blocked by the wing, resulting in different cooling rates of the primary fibers in different directions. Figure 1 、 2 .

[0032] The spinning process includes the following steps:

[0033] The melt of the fiber-forming polymer is continuously, quantitatively and evenly extruded from the spinneret 2 of the spinneret 1 through a metering pump to form a liquid stream, which is then solidified in air, water or a specific coagulation bath to form a nascent fiber;

[0034] in,

[0035] The spinneret 2 includes a guide hole 21 and a microhole 22. The microhole 22 includes a first hole 221, a second hole 222 and a third hole 223 connected vertically in sequence. The first hole 221, the second hole 222 and the third hole 223 form a wide-wing I-shaped cross section in the spinning process.

[0036] During the spinning process, the hole wall of the second hole 222 is continuously cooled so that the web temperature of the spun fiber leaving the spinneret 1 is lower than the wing temperature of the spun fiber, thereby ensuring that all parts of the spun fiber are cooled evenly when air-cooled.

[0037] The difference between the temperature of the inner wall of the second hole 222 and the temperature of the inner wall of the first hole 221 is selected according to the material of the spun fiber and the width of the pores.

[0038] The number of spinneret holes 2 of the spinneret 1 is 1 to 30,000, the cross-sectional area of ​​the micropore 22 is 0.12 mm² to 0.2 mm², the first hole 221 and the third hole 223 are symmetrical with respect to the second hole 222, the width of the first hole 221, the second hole 222 and the third hole 223 is 0.14 mm to 0.18 mm, the length of the first hole 221, the second hole 222 and the third hole 223 is 0.85 mm to 1.1 mm, and the ratio of the length of the micropore 22 to the length of the diagonal of the micropore 22 is 1.5 to 2.

[0039] The primary fibers include a web and a wing plate, the length of the web and the wing plate is 0.85 mm to 1.1 mm, and the width of the web and the wing plate is 0.14 mm to 0.18 mm.

[0040] The longitudinal cross-section of the guide hole 21 can be cylindrical, conical, hyperbolic, two-stage cylindrical or flat-bottomed cylindrical. The diameter of the entrance of the guide hole 21 is 0.6-0.8 mm.

[0041] There are generally two methods for cooling the hole wall of the second hole 222 .

[0042] Cooling method 1: direct cooling.

[0043] For example, cold air is directly sprayed onto the spinneret 1 to reduce the temperature around the second hole 222 and indirectly reduce the temperature of the hole wall of the second hole 222. This method has a simple structure, but the cooling range and cooling rate are difficult to control.

[0044] To improve this problem, please refer to Figure 3 、 4In the embodiment shown, a cooling oil channel 3 is formed inside the spinneret 1, and the inner wall of at least one section of the cooling oil channel 3 is close to the hole wall of the second hole 222, so that a first heat exchange plate 31 is formed between the cooling oil channel 3 and the second hole 222. Cooling oil circulates in the cooling oil channel 3 through a circulating pump to reduce the temperature of the inner wall of the second hole 222. By adjusting the cross-sectional area of ​​the cooling oil channel 3, the cooling range can be adjusted, and by adjusting the flow rate of the cooling oil, the cooling rate can be adjusted.

[0045] In order to facilitate the processing of the cooling oil channel 3, the spinneret 1 includes a first plate 11, a second plate 12 and a third plate 13 connected in sequence by bolts. A guide hole 21 is formed on the first plate 11, and micropores 22 are formed on the second plate 12 and the third plate 13. The guide hole 21 and the micropores 22 are connected. Cooling oil holes 32 are respectively formed on the sides of the second plate 12 and the third plate 13 that are close to each other. When the second plate 12 and the third plate 13 are attached to each other, the two cooling oil holes 32 are combined into a cooling oil channel 3.

[0046] A sealing gasket is provided between the two cooling oil holes 32 , although the sealing gasket is not shown in the figures.

[0047] In order to facilitate the arrangement of the cooling oil pipes, a plurality of grooves 14 surrounding the micropores 22 and communicating with each other are formed on the spinneret 1 . The depth of the grooves 14 is equal to the thickness of the second plate 12 and the third plate 13 .

[0048] The figure does not show the circulation pump and cooling oil pipe. The cooling oil pipe is insulated by thermal insulation material and embedded in the inside of the groove 14. The wall cooling oil pipe blocks the cooling air blowing onto the surface of the spun fiber.

[0049] The grooves 14 include annular grooves 141 and linear grooves 142. The annular grooves 141 are distributed on several concentric circles with the center of the spinneret 1 as the center. Two adjacent annular grooves 141 are connected by linear grooves 142. The linear grooves 142 are distributed on radial lines with the center of the spinneret 1 as the center.

[0050] Cooling method 2: heat pump cooling.

[0051] By setting the cooling side of the heat pump near the second hole 222, the heat of the second hole 222 is transferred to the outside of the spinneret 1. This embodiment is not shown in the figure. For example, the heat absorption side of the heat pump is embedded in the inside of the spinneret 1, and the heat absorption side of the heat pump is close to the hole wall of the second hole 222.

[0052] The heat pump adopts a semiconductor refrigeration plate, and the heat absorption side of the semiconductor refrigeration plate at least partially replaces the hole wall of the second hole 222.

[0053] Furthermore, since the hole wall of the second hole 222 is continuously cooled, this will also cause the temperature of the hole walls of the first hole 221 and the third hole 223 to gradually decrease. In order to solve this problem, the production process also includes the following steps: continuously heating the hole walls of the first hole 221 and the third hole 223 during the spinning process so that the temperature of the first hole 221 and the third hole 223 is always constant.

[0054] Please refer to Figure 5 Similar to the cooling oil channel 3, a heating oil channel 4 is formed inside the spinneret 1, and the inner wall of at least one section of the heating oil channel 4 is close to the hole walls of the first hole 221 and the third hole 223, so that a second heat exchange plate 41 is formed between the heating oil channel 4 and the first hole 221 and the third hole 223. The heating oil circulates in the heating oil channel 4 through a circulating pump to maintain the temperature of the inner walls of the first hole 221 and the third hole 223. By adjusting the cross-sectional area of ​​the heating oil channel 4, the heating range can be adjusted, and by adjusting the flow rate of the heating oil, the heating rate can be adjusted.

[0055] The heating oil passage 4 is also formed by combining the heating oil holes 42 formed on the second plate 12 and the third plate 13 .

[0056] Example 2

[0057] On the other hand, the air permeability of the wing plate can be improved by making holes in the wing plate, thereby accelerating the cooling rate of the web plate, so that the wing plate and the web plate are cooled evenly.

[0058] The specific spinning process includes the following steps:

[0059] The fiber-forming polymer and the pore-forming agent are mixed and heated to a melt state to obtain a mixed melt;

[0060] The mixed melt is continuously, quantitatively and evenly extruded from the spinneret 2 of the spinneret 1 by a metering pump to form a liquid stream, which is then solidified in air, water or a specific coagulation bath to form a nascent fiber;

[0061] in,

[0062] The spinneret 2 includes a guide hole 21 and a microhole 22. The microhole 22 includes a first hole 221, a second hole 222 and a third hole 223 connected vertically in sequence. The first hole 221, the second hole 222 and the third hole 223 form a wide-wing I-shaped cross section in the spinning process.

[0063] During the spinning process, the hole wall of the second hole 222 is continuously cooled so that the web temperature of the spun fiber leaving the spinneret 1 is lower than the wing temperature of the spun fiber. At the same time, the pore-forming agent is decomposed by heat to produce gas, so that bubbles and pores are generated on the surface of the spun fiber, thereby ensuring that all parts of the spun fiber can be evenly cooled when air-cooled.

[0064] The pore-forming agent used is NH4HCO3. Upon thermal decomposition, NH4HCO3 produces NH3, CO2, and water vapor. NH3 reacts with water to form ammonia, while CO2 is released into the atmosphere. The pores on the surface of the spun fiber provide excellent ventilation, allowing cooling air to pass through the pores on the wing plate and onto the web.

[0065] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the scope of the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the spirit and scope of protection of the present invention, and such modifications or equivalent substitutions shall also be deemed to fall within the scope of protection of the embodiments of the present invention.

Claims

1. A spinning process for bending-resistant wide-wing I-beam cross-section wire strips, characterized in that: The following steps are involved: The melt of the fiber-forming polymer is squeezed out from the spinneret holes through a metering pump to form a liquid stream, which is then solidified in a coagulation bath to form nascent fibers. in, The spinneret includes a guide hole and a microhole, the microhole includes a first hole, a second hole and a third hole connected vertically in sequence, and the first hole, the second hole and the third hole form a wide-wing I-shaped cross section in the spinning process; The hole wall of the second hole is continuously cooled during the spinning process so that the web temperature of the spun fiber leaving the spinneret is lower than the wing temperature of the spun fiber.

2. The spinning process of a bending-resistant wide-wing I-beam cross-section wire strip according to claim 1, characterized in that: The cross-sectional area of ​​the micropore is 0.12 mm² to 0.2 mm², the ratio of the length of the micropore to the length of the diagonal of the micropore is 1.5 to 2, and the first hole and the third hole are symmetrical with respect to the second hole.

3. The spinning process of the bending-resistant wide-wing I-beam cross-section wire strip according to claim 2, characterized in that: The widths of the first hole, the second hole, and the third hole are 0.14 mm to 0.18 mm, and the lengths of the first hole, the second hole, and the third hole are 0.85 mm to 1.1 mm.

4. The spinning process of the bending-resistant wide-wing I-beam cross-section wire strip according to claim 2, characterized in that: The diameter of the entrance of the guide hole is 0.6-0.8 mm.

5. The spinning process of the bending-resistant wide-wing I-beam cross-section wire strip according to claim 1, characterized in that: A cooling oil channel is formed inside the spinneret, and an inner wall of at least one section of the cooling oil channel is close to the hole wall of the second hole, so that a first heat exchange plate is formed between the cooling oil channel and the second hole, and cooling oil circulates in the cooling oil channel to reduce the temperature of the inner wall of the second hole.

6. The spinning process of the bending-resistant wide-wing I-beam cross-section wire strip according to claim 1, characterized in that: The heat absorbing side of the heat pump is embedded in the spinneret, and the heat absorbing side of the heat pump is close to the hole wall of the second hole.

7. The spinning process of the bending-resistant wide-wing I-beam cross-section wire strip according to claim 5 or 6, characterized in that: During the spinning process, the hole walls of the first hole and the third hole are continuously heated so that the temperatures of the first hole and the third hole are always constant.

8. The spinning process of the bending-resistant wide-wing I-beam cross-section wire strip according to claim 7, characterized in that: A heating oil channel is formed inside the spinneret, and an inner wall of at least one section of the heating oil channel is close to the hole walls of the first hole and the third hole, so that a second heat exchange plate is formed between the heating oil channel and the first hole and the third hole. Heating oil circulates in the heating oil channel to maintain the temperature of the inner walls of the first hole and the third hole.

9. A spinning process for a bending-resistant wide-wing I-beam cross-section wire strip according to any one of claims 1 to 8, characterized in that: Before heating the fiber-forming polymer, the fiber-forming polymer and the pore-forming agent are mixed. During the spinning process, the pore-forming agent is decomposed by heat to generate gas, so that bubbles and pores are generated on the surface of the nascent fiber.

10. The spinning process of the bending-resistant wide-wing I-beam cross-section wire strip according to claim 9, characterized in that: The pore former is NH4HCO3.

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