Method for improving the uniformity of the full-width warp tension of nylon 66 dipped cord fabric

Abstract

The present invention belongs to the field of tire manufacturing, especially to the field of production of dipped cord fabric for tires, and specifically relates to a method for improving the uniformity of the full-width warp tension of nylon 66 dipped cord fabric. The method includes: Step 1: Analyze the forces acting on the warps entering the gathering plate, and calculate the tension differences of each warp; then, according to the magnitude of the consistent F4 (the tension perpendicular to the gathering plate after the warps enter the rear gathering plate), calculate the required F1 (the warp tension from the yarn creel gathering plate to the rear gathering plate) for each warp; Step 2: Take measures to adjust the magnitude of F1 to improve the tension uniformity of each warp at the gathering plate. By modeling and analyzing the force conditions in different regions of the entire fabric surface, the present invention corrects the force conditions on the fabric surface at key force-bearing positions, which can reduce the tension differences of the warps. It makes the full-width warp tension of the green fabric more uniform and reduces the deviation phenomenon existing after dipping and unwinding.

Description

Technical Field

[0001] The present invention belongs to the field of tire manufacturing, especially to the field of production of dipped cord fabric for tires, and particularly relates to a method for improving the uniformity of the full-width warp tension of nylon 66 dipped cord fabric. Background Art

[0002] Nylon 66 dipped cord fabric is processed and produced from multiple warp threads of the same fineness according to certain warp density requirements through the weaving process and the dipping process. The entire production line has a long process. The white blank weaving process includes processes such as unwinding of complex-twisted yarns, guide wire plates, back reeds, dividing rods (drop wires), heddles, weaving, and winding. The dipping process includes processes such as unwinding of the white blank fabric, dipping, stretching and heat treatment, and winding.

[0003] Due to the limited capacity of the existing equipment and simple processing technology control, it is difficult to ensure the uniformity of the warp tension of the full-width nylon 66 dipped fabric. As a result, when used in dipping production or when the tire enterprise unwinds by calendering, the nylon 66 cord fabric shows technical problems such as different degrees of tight edges, loose edges, and bulging, as shown in the attached drawings of the specification. Figure 1 as shown

[0004] Tracing the entire processing process, the following key influencing factors related to the above technical problems exist in each production link:

[0005] (1) During the process of weaving the white blank fabric, due to the deviation of the horizontal degree of the front and rear rollers or the difference in the full-width warp tension, the white blank fabric is not centered before and after during the weaving process.

[0006] (2) During the dipping heat treatment process, the cord fabric undergoes multiple tension stretching and heat treatment processes and passes through hundreds of rollers. If the horizontal degree and parallelism of each roller deviate, it will affect the uniformity of the fabric surface tension. Even if the deviation amount of the horizontal degree and parallelism of each roller itself is very small, due to the large number of roller rolls passed through, if the deviation amounts of all the rollers accumulate on one side, a superimposed effect will be generated, which will have a certain impact on the uniformity of the fabric surface tension. The warp threads at different positions in the width direction will have different stresses and strains. After dipping treatment, the lengths of the warp threads at different positions in the width direction will be different.

[0007] (3) After the dipped fabric is taken off the machine and placed flat on the ground, observing the horizontal degree on both sides in the width direction, the edge position about 10 cm is slightly higher than other intermediate positions by about 3 - 8 mm. The main reason is caused by the folding back of the edge weft yarns. This causes the warp tension at the edges to be large. As it is placed for a long time, the mechanical properties of the warp threads change, which is the so-called creep effect in the traditional sense. The greater the tension, the greater the creep rate generated by the warp threads, resulting in differences in the full-width warp tension and prone to the phenomenon of loose edges, especially in the first about 300 m used in tire calendering, which will be more serious.

[0008] In the prior art, in order to make the warp tension relatively uniform in the width direction of the impregnated cloth, during the weaving of the grey cloth, many measures are taken, such as improving the time management standard of the winding of the twisted yarn (balancing for more than 24 hours before using the double-twisted yarn, controlling the balance time difference of all the twisted yarn bobbins on the same creel within 120 hours, optimizing the use of the spring of the wire inserting spindle of the large yarn rack, designing and implementing the edge wire preparation plan), etc.

[0009] However, during the impregnation production process, there are still technical problems such as deviation and wrinkle caused by uneven warp tension of the grey cloth. In each tension area and the front and rear cloth storage racks, there is also a situation where the nylon 66 cord fabric deviates from one side of the roller, and in severe cases, quality accidents such as the grey cloth or the impregnated cloth falling off the roller and splitting occur.

[0010] In addition, in the prior art, there is no effective method to actually measure the tension values of thousands of warp threads unwound from the wire inserting spindle of the large yarn rack, so effective measures cannot be taken to optimize the tension size to make the tension of all the warp threads relatively more uniform after unwinding.

[0011] Furthermore, during the unwinding of the grey cloth and the heat treatment of the impregnated cloth, the horizontal degree of the rollers passed through is not horizontal, which will cause abnormal situations such as deviation of the grey cloth and the impregnated cloth. Due to the large number of rollers, the degree of deviation cannot be observed by the naked eye, and the measurement of the horizontal degree of each roller can only be carried out one by one during the parking period, with a large workload and unable to effectively prevent the generation of defective products in a timely manner. Summary of the Invention

[0012] In order to make the warp tension relatively uniform in the width direction of the nylon 66 impregnated cloth, the present invention proposes a method for improving the uniformity of the warp tension of the nylon 66 impregnated cord fabric. The present invention measures the tension size of each warp thread from the unwinding tension rack to the wire collecting plate during the weaving of the grey cloth, establishes a mathematical model, and accurately adjusts the unwinding tension to achieve the uniformity of the warp tension of the whole width.

[0013] The present invention uses a yarn tension meter to measure the tension size of each warp thread from the unwinding tension rack to the wire collecting plate, and finds that there are slight differences in its size. Although this slight difference has little impact during the weaving of the grey cloth, different degrees of width direction deviation will occur during the subsequent process - the unwinding and use of the grey cloth, and it is difficult to correct in severe cases, affecting the normal production and use.

[0014] The method for improving the uniformity of the warp tension of the nylon 66 impregnated cord fabric of the present invention includes the following contents:

[0015] Step 1: Analyze the force on the warp threads entering the wire collecting plate, calculate the tension difference of each warp thread, and the tension difference of each warp thread is calculated by the following formula:

[0016]

[0017] In the formula,

[0018] F1 is the warp tension from the yarn creel gathering plate to the rear gathering plate;

[0019] F2 is the vertical projection of the warp tension from the yarn creel gathering plate to the rear gathering plate;

[0020] F3 is the tension perpendicular to the gathering plate before the warp enters the rear gathering plate;

[0021] F4 is the tension perpendicular to the gathering plate after the warp enters the rear gathering plate;

[0022] α is the angle between the warp and the horizontal plane, and β is the angle between the warp and the vertical plane perpendicular to the yarn creel gathering plate;

[0023] L1 is the length of the warp concentrated from the yarn creel gathering plate to the rear gathering plate, L2 is the height difference between the yarn creel gathering plate and the rear gathering plate, and L3 is the horizontal distance from the yarn creel gathering plate to the rear gathering plate, and this value is a constant;

[0024] μ1 is the correction value of the friction coefficient of the wire inserting spindle in the horizontal direction, and μ1 is a constant 1.01; n refers to the order number of the wire inserting spindles at the same level from right to left.

[0025] For the wire inserting spindles at different positions of the unwinding tension frame, the α angle and β angle passing through the yarn creel gathering plate and the rear gathering plate are different. Finally, it is necessary to make the warp tensions F4 of each thread consistent. According to the magnitude of the required F4, the required F1 for each warp is calculated through the established above formula.

[0026] Step 2: Take measures to adjust the magnitude of F1 to improve the tension uniformity of each warp at the gathering plate.

[0027] Changing the unwinding tension at the warp F1 can be achieved by increasing or decreasing the unwinding tension of the warp at the outlet of the wire inserting spindle. The unwinding tension at the outlet of the wire inserting spindle is calculated by the following formula:

[0028]

[0029] Specifically, the following measures are taken to adjust the unwinding tension of the warp:

[0030] Method 1: By changing the size of the spring at the head of the wire inserting spindle, change the spring unwinding friction coefficient of the wire inserting spindle;

[0031] When the spring diameter of the wire inserting spindle is 0.7 mm (i.e., the spring grade is grade 2), the spring unwinding friction coefficient of the wire inserting spindle is μ2, and μ2 is a constant 1.03. The relationship between the spring unwinding friction coefficient (μ T ) of the wire inserting spindle and the spring grade (t) of the wire inserting spindle is μ T = μ2 t-1 = 1.03 t-1。

[0032] And / or: Method 2: By changing the roughness of the felt sheet at the bottom of the wire-inserting ingot, the unwinding friction coefficient of the felt sheet of the wire-inserting ingot is changed.

[0033] When the roughness of the felt sheet of the wire-inserting ingot is 0.126 μm (i.e., the felt sheet grade is Grade 2), the unwinding friction coefficient of the felt sheet of the wire-inserting ingot is μ3, and μ3 is a constant 1.02. The unwinding friction coefficient (μ M ) of the felt sheet of the wire-inserting ingot and the grade (m) of the felt sheet of the wire-inserting ingot have the relationship of μ M = μ3 m-1 = 1.02 m-1 。

[0034] The beneficial effects of the present invention are as follows:

[0035] By monitoring the warp tension magnitudes at different regional positions, modeling and analyzing the force conditions of different regions of the entire cloth surface, and correcting the force conditions of the cloth surface at the key force-bearing positions, the present invention can reduce the tension difference of the warps, make the warp tensions of the entire width of the grey cloth more uniform, and reduce the deviation phenomenon existing after dipping and unwinding. Description of the Drawings

[0036] Figure 1 It is a common situation diagram of nylon 66 dipped cord fabric during dipping production use and during calendering and unwinding by tire enterprises.

[0037] Figure 2 It is a structural schematic diagram of unwinding tension frames, warps, yarn frame wire collecting plates, and rear wire collecting plates at different positions. In the figure, A is a top view, B and C are both left views, and D and E are structural schematic diagrams of the yarn frame wire collecting plate and the warp.

[0038] Figure 3 It is the unwinding tension magnitudes at F1 and F3 during the weaving of 2800 dtex / 2 nylon 66 grey cloth before and after improvement.

[0039] Figure 4 It is the unwinding tension at F1, the unwinding tension at F3, and F 锭 during the weaving of the improved 2800 dtex / 2 nylon 66 grey cloth.

[0040] Figure 5 It is the position of the spring in the wire-inserting ingot, and the spring is located behind the yellow component.

[0041] Figure 6 It is the position of the felt sheet in the wire-inserting ingot, and the circular structure indicated by the arrow in the figure is the felt sheet.

[0042] Figure 7 It is the theoretical value and measured value (I) at F4 during the weaving of the improved 1400 dtex / 2 nylon 66 grey cloth.

[0043] Figure 8 For the theoretical and measured values of F4 treatment during the weaving of the improved 1400dtex / 2 nylon 66 grey fabric (Part 2).

[0044] In the figure, 1 is the unwinding tension frame, 2 is the warp thread, 3 is the yarn rack wire collecting plate, 4 is the rear wire collecting plate, and 5 is the wire inserting spindle.

[0045] In the figure, the right 1 and the upper single indicate the wire inserting spindles above the upper area closest to the yarn rack wire collecting plate,

[0046] the right 2 and the upper double indicate the wire inserting spindles below the upper area closest to the yarn rack wire collecting plate,

[0047] the right 1 and the middle single indicate the wire inserting spindles above the middle area closest to the yarn rack wire collecting plate,

[0048] the right 2 and the middle double indicate the wire inserting spindles below the middle area closest to the yarn rack wire collecting plate,

[0049] the right 1 and the lower single indicate the wire inserting spindles above the lower area closest to the yarn rack wire collecting plate,

[0050] the right 2 and the lower double indicate the wire inserting spindles below the lower area closest to the yarn rack wire collecting plate. Detailed implementation method

[0051] The present invention will be described in more detail below through specific implementation methods to facilitate the understanding of the technical solution of the present invention, but it is not used to limit the protection scope of the present invention.

[0052] The method for improving the uniformity of the full-width warp tension of nylon 66 dipped cord fabric of the present invention includes the following contents:

[0053] 1. Analyze the forces on the warp threads entering the wire collecting plate and calculate the tension differences of each warp thread

[0054] If we want to improve the uniformity of the full-width warp tension of nylon 66 dipped cord fabric, we need to make the tensions of all warp threads the same after passing through the wire collecting plate during the weaving of nylon 66 grey fabric. Therefore, we need to first analyze the forces on each warp thread and calculate the tension differences of each warp thread.

[0055] When the warp threads are unwound, the warp threads are unwound through the unwinding tension frame and then concentrated on the yarn rack wire collecting plate and the rear wire collecting plate in sequence (the wire collecting plate includes the yarn rack wire collecting plate close to the unwinding tension frame and the rear wire collecting plate located behind the yarn rack wire collecting plate), and then enter the weaving process through the dividing rod downstream of the wire collecting plate. In actual production, several unwinding tension frames will be set in front of the yarn rack wire collecting plate, and several wire inserting spindles will be arranged from top to bottom on each unwinding tension frame.

[0056] In a specific embodiment, as viewed from the top view of the unwinding tension frame ( Figure 2 Figure A therein), the unwinding tension frame is divided into 3 regions: the middle region and the two side regions. There are 2 rows of unwinding tension frames in each region. From the position of the unwinding tension frame close to the yarn rack wire collecting plate to the end of the unwinding tension frame ( Figure 2 the left side of Figure A therein), every interval of length L is one unit, and each unit contains 6 wire inserting spindles (as viewed from Figure 2 Figure B therein, there are 6 wire inserting spindles from top to bottom in each unit). Finally, thousands of warp threads are concentrated on the rear wire collecting plate and then enter the weaving process through the dividing rod downstream of the rear wire collecting plate.

[0057] Since the warp threads concentrated on the rear wire collecting plate come from the wire inserting spindles of different unwinding tension frames or from the wire inserting spindles at different heights of the same unwinding tension frame, there are differences in the forces on each warp thread when unwinding from the unwinding tension frame to the wire collecting plate.

[0058] As can be seen from Figure 2 , the warp threads in the two side regions (the upper region and the lower region) are farther from the rear wire collecting plate, so the unwinding tension is slightly larger than that in the middle side. It is considered that the unwinding tension of the warp threads in the middle region can be increased by adopting different upward tilting angles of the wire inserting spindles in a zoned design (such as 7° in the middle side and 5° on both sides). However, since the warp threads in the same region are at different front and rear positions of the unwinding tension frame, there are differences in the length from the wire collecting plate and slight differences in the angle relative to the wire collecting plate. Even if the wire inserting spindles adopt different upward tilting angles according to their positions in the region, it cannot ensure the uniformity of the tensions of all warp threads after passing through the wire collecting plate.

[0059] The force analysis in this step is to analyze the magnitude of the force on the warp thread from the wire inserting spindle on the unwinding tension frame to the rear wire collecting plate:

[0060] F1 is the tension of the warp thread from the yarn rack wire collecting plate to the rear wire collecting plate section;

[0061] F2 is the vertical projection of the tension of the warp thread from the yarn rack wire collecting plate to the rear wire collecting plate section;

[0062] F3 is the tension perpendicular to the wire collecting plate before the warp thread enters the rear wire collecting plate;

[0063] F4 is the tension perpendicular to the wire collecting plate after the warp thread enters the rear wire collecting plate, as shown in Figure 2 Figure B therein.

[0064] From the top view of the unwinding tension frame, we get: F4 = F3 (1);

[0065] From the left view of the unwinding tension frame (taking the warp thread coming out of the rightmost wire inserting spindle of the upper unwinding tension frame as an example), we get:

[0066] F3 = F2 * cosβ (2);

[0067] F2 = F1 * cosα (3);

[0068] From (1), (2), and (3), we get Equation (4), F4 = F1 * cosα * cosβ (4).

[0069] Where, α—the angle between the warp and the horizontal plane;

[0070] β—the angle between the warp and the vertical plane perpendicular to the yarn rack collecting plate, as shown in Figure 2 Figure D and Figure 2 Figure E in.

[0071] α and β can be obtained through measurement or calculation:

[0072]

[0073] L1—the length of the warp from the yarn rack collecting plate to the rear collecting plate after concentration;

[0074] L2—the height difference between the yarn rack collecting plate and the rear collecting plate;

[0075] L3—the horizontal distance from the yarn rack collecting plate to the rear collecting plate, which is a constant value, usually 5 - 7 m. As shown in Figure 2 Figure C in.

[0076] Substitute Equations (5) and (6) into Equation (4) to get Equation (7):

[0077]

[0078] Therefore, the angles α and β can be obtained by two methods, namely, calculating with Equations (5) and (6) or directly measuring the angles.

[0079] From the above formulas, it can be concluded that: the values of α and β jointly determine the magnitude of F4, and it cannot be simply measured by "the distance between the yarn rack collecting plate and the rear collecting plate to measure F4".

[0080] As Figure 3 shown, taking the 2800 dtex / 2 dipped fabric as an example, before improvement, the unwinding tension at F1 is consistent, which is 300 cN, that is, F1 is a fixed value. After improvement, calculate and adjust the unwinding tension that each warp needs to maintain at F1 to make the tension at F4 (i.e., F3) consistent (closer to the weaving tension), which is 300 cN.

[0081] According to Figure 2 Figure A in, the spacing between the left and right adjacent wire inserting spindles is L. For the wire inserting spindles on the same side, in the same row, and at the same level, the farther to the left (taking the Figure 2 direction in Figure A as the standard), the farther the distance from the collecting plate. Taking Figure 2Taking the direction of Figure A as the standard, for the horizontal wire-inserting spindles, from right to left are the 1st wire-inserting spindle, the 2nd wire-inserting spindle... the nth wire-inserting spindle in sequence. For each additional spacing L between each wire-inserting spindle and the rightmost wire-inserting spindle, the unwinding friction coefficient of this wire-inserting spindle increases by one power, where the unwinding friction coefficient is a constant.

[0082] Substitute the unwinding friction coefficient into Equation (7) to obtain Equation (8):

[0083]

[0084] μ1 is the correction value of the friction coefficient of the horizontal wire-inserting spindle, and μ1 is the constant 1.01.

[0085] Through the established mathematical model Equation (8), the tension difference at the position of the wire-collecting plate after thousands of warp threads arrive can be calculated.

[0086] 2.2. Study the relevant factors affecting F1, and the system takes measures to adjust the size of F1 to improve the tension uniformity of each warp thread at the wire-collecting plate

[0087] If the unwinding tension of the warp threads at the wire-collecting plate is to be uniform, then F3 (i.e., F4) needs to be kept consistent.

[0088] For the wire-inserting spindles at different positions of the unwinding tension frame, due to being in different zones (upper zone, middle zone, lower zone) and different heights, the α angle and β angle passing through the yarn rack wire-collecting plate and the rear wire-collecting plate are different. Ultimately, to achieve the same tension F4 for each warp thread, the required F1 for each warp thread is calculated through the established mathematical model (8). Changing the unwinding tension at the F1 position of the warp thread can be achieved by increasing or decreasing the unwinding tension of the warp thread at the outlet of the wire-inserting spindle.

[0089] The unwinding tension at the outlet of each wire-inserting spindle can be calculated through Equation (9):

[0090]

[0091] Such as Figure 4 shown, taking the 2800dtex / 2 dipped fabric as an example, the unwinding tension F of the warp thread at the outlet of the wire-inserting spindle 锭 is calculated and statistically obtained: maximum value: 355.4 cN, minimum value: 301.9 cN, average value: 326.3 cN.

[0092] Specifically, the following measures can be taken to adjust the unwinding tension of the warp thread:

[0093] After actual measurement, the sizes of each wire-inserting spindle are the same, and no damping measures are taken on the wire-inserting spindle. The actually measured unwinding tensions are the same, all being F 锭 = 295 cN; if you want to make F 锭When the unwinding tension reaches the theoretically calculated level, a spring with a larger diameter or a felt sheet with a higher roughness can be used to increase the damping (i.e., frictional force) of the wire inserting spindle during unwinding.

[0094] Method 1: Change the size of the spring at the head of the wire inserting spindle to increase the unwinding friction coefficient μ2 of the spring of the wire inserting spindle. μ2 is a constant of 1.03. The diameter of the spring is divided into t grades (t: 1 to 10). Using springs of different grades results in different unwinding friction coefficients, which can be expressed by the formula: μ T = μ2 t-1 = 1.03 t-1 .

[0095] The springs are differentiated according to their diameters, from Φ0.6mm to Φ1.5mm (each 0.1mm is a grade).

[0096] Table 1 Related parameters of springs with different diameters

[0097] Spring grade N 1 2 3 4 5 6 7 8 9 10 Spring diameter mm 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 Coefficient of friction 1.00 1.03 1.06 1.09 1.13 1.16 1.19 1.23 1.27 1.30

[0098] The position of the spring in the wire inserting spindle is as Figure 5 shown.

[0099] Method 2: Use felt sheets with different roughnesses at the bottom of the wire inserting spindle to change the unwinding friction coefficient μ3 of the felt sheet of the wire inserting spindle. μ3 is a constant of 1.02. The roughness of the felt sheet is divided into m grades (m: 1 to 4). Using felt sheets with different roughnesses results in different increases in the unwinding friction coefficient, which can be expressed by the formula: μ M = μ3 m-1 = 1.02 m-1 .

[0100] Table 1 Related parameters of felt sheets with different roughnesses

[0101] Felt sheet grade N 1 2 3 4 Felt sheet roughness μm 0.112 0.126 0.14 0.16 Coefficient of friction 1.00 1.02 1.04 1.06

[0102] The position of the felt sheet in the wire inserting spindle is as Figure 6 shown.

[0103] Application Example 1:

[0104] When weaving 1400dtex / 2 dipped cord fabric (the warp weight on the wire inserting spindle is about 8 kg) on the grey cloth loom, usually, 1st grade springs and 1st grade felt sheets are installed, and the unwinding tension of the warp at the outlet of each wire inserting spindle is about F 锭＝ 270 cN.

[0105] Due to the differences in the distances and angles of each wire inserting spindle to the collecting plate, to ensure the uniformity of F4 (usually controlling the tension: 345 cN), by calculating F 锭The actual required unwinding tension of the warp yarn at the exit of the wire-inserting ingot is made relatively uniform for F4 by using a spring size and felt sheet of appropriate diameter. After adjustment, the measured F4 tension approaches the theoretical value, as Figure 7 shown.

[0106] Application Example 2:

[0107] When weaving the 1400 dtex / 2 dipped cord fabric (the weight of the warp yarn on each wire-inserting ingot is about 6 kg) into the grey fabric, usually, a Grade 1 spring and a Grade 1 felt sheet are installed, and the unwinding tension of the warp yarn at the exit of each wire-inserting ingot is about F 锭＝ 235 cN.

[0108] Due to the different differences in the distances and angles of each wire-inserting ingot to the wire collecting plate after arrival, to ensure the uniformity of F4 (usually controlling the tension: 290 cN), assuming that the F4 tension is uniform, the warp yarn on each wire-inserting ingot is calculated according to its position for F 锭 The actual required unwinding tension of the warp yarn at the exit of the wire-inserting ingot is made relatively uniform for F4 by using a spring size and felt sheet of appropriate diameter. After adjustment, the measured F4 tension approaches the theoretical value, as Figure 8 shown.

[0109] The above test results are slightly larger than the theoretical calculated values, which is normal. To ensure the uniformity of the warp yarn tension at F4, a mathematical model is used to calculate the theoretical values that each ingot needs to control for F 锭 and appropriate spring and felt sheet grades are used to make the F 锭 actual unwinding tension approach the theoretical value, so that the actual measured tension results of each warp yarn at F4 are relatively uniform, thereby improving the uniformity of the grey fabric surface tension.

[0110] The above-described embodiments are only the preferred embodiments of the present invention and do not limit the scope of implementation of the present invention. Therefore, any equivalent changes or modifications made according to the structure, features, and principles described in the scope of the present invention patent shall be included in the scope of the patent application of the present invention.

Claims

1. A method for improving the uniformity of the full-width warp tension of nylon 66 dipped cord fabric, characterized in that Including: Step 1: Conduct a force analysis on the warp threads entering the wire collecting plate, and calculate the tension differences of each warp thread. The tension differences of each warp thread are calculated by the following formula: In the formula, F1 is the warp thread tension from the yarn creel wire collecting plate to the rear wire collecting plate; F2 is the vertical projection of the warp thread tension from the yarn creel wire collecting plate to the rear wire collecting plate; F3 is the tension perpendicular to the wire collecting plate before the warp thread enters the rear wire collecting plate; F4 is the tension perpendicular to the wire collecting plate after the warp thread enters the rear wire collecting plate; α is the angle of the warp thread relative to the horizontal plane, β is the angle of the warp thread relative to the vertical plane perpendicular to the yarn creel wire collecting plate; L1 is the length of the warp threads concentrated to the rear wire collecting plate after coming out of the yarn creel wire collecting plate, L2 is the height difference between the yarn creel wire collecting plate and the rear wire collecting plate, L3 is the horizontal distance from the yarn creel wire collecting plate to the rear wire collecting plate, and the value of L3 is a constant of 5 - 7; μ1 is the correction value of the friction coefficient of the wire inserting spindle in the horizontal direction, μ1 is a constant of 1.01; n refers to the sequence number of the wire inserting spindles at the same level from right to left; According to the required consistent magnitude of F4, calculate the required F1 for each warp thread through the above formula; Step 2: Take measures to adjust the magnitude of F1 to improve the tension uniformity of each warp thread at the wire collecting plate.

2. The method according to claim 1, wherein In Step 2, the unwinding tension of the warp thread at F1 is changed by increasing or decreasing the unwinding tension of the warp thread at the outlet of the wire inserting spindle. The unwinding tension at the outlet of the wire inserting spindle is calculated by the following formula:

3. The method according to claim 2, wherein The unwinding tension of the warp thread is adjusted by taking the following measures: Method 1: By changing the size of the spring at the head of the wire inserting spindle, change the spring unwinding friction coefficient of the wire inserting spindle; and / or: Method 2: By changing the roughness of the felt sheet at the bottom of the wire inserting spindle, change the felt sheet unwinding friction coefficient of the wire inserting spindle.

4. The method according to claim 3, wherein The relationship between the spring unwinding friction coefficient of the wire-inserting ingot and the spring grade of the wire-inserting ingot is μ T = μ2 t-1 = 1.03 t-1 , where μ T is the spring unwinding friction coefficient of the wire-inserting ingot, t is the spring grade of the wire-inserting ingot, and μ2 is the spring unwinding friction coefficient of the wire-inserting ingot when the spring grade of the wire-inserting ingot is grade 2.

5. The method according to claim 3, wherein The relationship between the unwinding friction coefficient of the felt sheet of the wire-inserting ingot and the grade of the felt sheet of the wire-inserting ingot is μ M = μ3 m-1 = 1.02 m -1 , where μ M is the unwinding friction coefficient of the felt sheet of the wire-inserting ingot, m is the grade of the felt sheet of the wire-inserting ingot, and μ3 is the unwinding friction coefficient of the felt sheet of the wire-inserting ingot when the grade of the felt sheet of the wire-inserting ingot is 2

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