A process for processing super coarse spun yarn without draft

Abstract

This invention discloses a non-drafting process for ultra-coarse single yarn, belonging to the field of wool spinning technology. Addressing the challenges of traditional ring spinning, which struggles to stably produce 0.2Nm-grade ultra-coarse pure wool single yarn due to poor evenness, significant fiber damage, and long processing times, this invention uses a 36μm New Zealand wool combed sliver to produce a combed sliver with a basis weight of 4.8g / m to 5.2g / m. The ring spinning machine is modified to eliminate drafting by removing the middle and back rollers and apron assembly, retaining the front roller and adding a guide device. Single slivers are fed in and twisted at a total draft ratio of 0.98 to 1.02, resulting in 0.2Nm / 1 ultra-coarse single yarn. This process preserves the natural bulk and elasticity of wool, produces uniform and stable yarn, simplifies equipment modification, significantly improves production efficiency, and is suitable for large-scale production.

Description

Technical Field

[0001] This invention belongs to the field of wool spinning and processing technology, and particularly relates to a non-drafting processing technology for ultra-coarse single yarn. Background Technology

[0002] Metric yarn count (Nm) is a commonly used indicator of yarn linear density; a lower count indicates a coarser yarn. In recent years, with the development of niche markets such as specialty woolen fabrics, home decor textiles, and artistic hand-knitted fabrics, the market demand for ultra-coarse woolen yarns below 0.5 Nm has gradually increased due to their robust and full appearance and fluffy, warm properties. Ring spinning is currently the mainstream technology in wool textile production. Its core lies in using a three-roller double-loop drafting system to perform multi-stage drafting and thinning of the wool sliver, followed by twisting and winding to produce yarn. It is suitable for the large-scale production of medium-fine count woolen yarns.

[0003] However, there are insurmountable technical bottlenecks when using traditional ring spinning machines to produce ultra-coarse single yarns:

[0004] First, the drafting system has poor adaptability, making it difficult to guarantee yarn quality. Extra-coarse yarns have high linear density, requiring a total draft ratio close to 1 for production. However, the drafting mechanism of conventional ring spinning is designed for medium to high draft ratios. Under near-zero drafting conditions, the speed difference between the front and rear rollers is extremely small, significantly weakening the gripping control of the fibers by the aprons and rollers. This leads to a surge in the number of floating fibers, easily causing disordered fiber arrangement, a severe decrease in yarn evenness, frequent occurrences of thick and thin spots and yarn defects, and failing to meet usage requirements.

[0005] Secondly, the drafting process damages the fibers and destroys the natural style of wool. In the traditional drafting process, the fiber slivers are repeatedly squeezed and stretched by rollers and aprons, which leads to wear on the scales on the surface of the wool, a decrease in fiber breaking strength, and loss of the original fluffy elasticity of wool. In the end, the yarn feels stiff, has reduced warmth retention, and loses the soft and fluffy texture that ultra-coarse yarn should have.

[0006] Third, the feeding quantity is limited and the process is lengthy. Due to the limited feeding capacity of the drafting mechanism, conventional spinning machines cannot directly feed large quantities of yarn to produce single-ply ultra-coarse yarn. Usually, it is necessary to first spin a finer single yarn, and then combine it through doubling and twisting processes to obtain coarse-ply yarn. This process involves many steps, a long production cycle, and the structural uniformity and overall style consistency of the combined yarn are not as good as those of single yarn products.

[0007] Currently, the alternative production processes for coarse-count yarns all have significant shortcomings: while running spinning can produce coarse-count wool yarn, its low spindle speed, poor production efficiency, and high cost for large-scale manufacturing; new spinning methods such as air-jet spinning and vortex spinning result in loose yarn structure, insufficient cohesion of wool fibers, low yarn strength, and severe hairiness, making them unsuitable for high-end applications. Existing publicly available non-draft spinning conversion schemes generally suffer from problems such as large equipment modifications, poor guide bar conveying, severe fiber wear, and poor twist uniformity, and are still unable to stably produce 0.2Nm grade ultra-coarse-count pure wool single yarn, making it difficult to simultaneously achieve yarn quality, production efficiency, and preservation of raw material characteristics. Summary of the Invention

[0008] To address the technical bottlenecks in the existing technology, the present invention aims to provide a non-drafting processing technology for ultra-coarse single yarn. By modifying the ring spinning machine to eliminate drafting, and combining it with a large-quantity combed wool sliver and near-zero drafting twisting process, the problem of traditional ring spinning being unable to stably produce 0.2Nm grade ultra-coarse pure wool single yarn is solved. At the same time, the natural fluffy texture of wool is preserved to the greatest extent, the production process is simplified, and production efficiency and yarn quality are improved.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A non-drafting processing technology for ultra-coarse single yarns specifically includes the following steps:

[0011] S1. Finishing of wool tops: 36μm New Zealand wool combed tops are processed by carding, and combed tops are prepared by combining and stretching, controlling the unit length mass of the combed tops to be 4.8g / m~5.2g / m;

[0012] S2. Spinning equipment modification: The ring spinning machine is de-drafted by removing the middle roller, back roller and apron drafting components, leaving only the front roller as the fiber sliver output and gripping component in the twisting area, and a guide device is installed behind the front roller.

[0013] S3, Undrafted Twisting: The combed sliver obtained in step S1 is fed to the front roller nip via the guide device. The output speed of the sliver is controlled by the front roller, and twisting is performed under the condition that the total draft ratio of the spinning machine is 0.98 to 1.02, so that the sliver maintains its original strip structure for spinning.

[0014] S4. Winding into yarn: The yarn obtained in step S3 is wound through a spindle and a wire traveler mechanism to obtain an ultra-coarse single yarn with a specification of 0.2Nm / 1.

[0015] Furthermore, in step S1, the length of the 36μm New Zealand wool fiber is 80mm to 110mm, and the combing process includes three combing steps; after the combing process, the fiber arrangement direction in the combed wool sliver is consistent, and the yield weight is preferably controlled at 5.0g / m.

[0016] Furthermore, in step S2, the guide strip device is located on the feed side of the front roller, and the surface of the guide strip device is set as a mirror polished structure or a polytetrafluoroethylene coating structure, which can effectively reduce the frictional resistance during the sliver conveying process and reduce fiber fuzzing and sliver deformation.

[0017] Furthermore, in step S3, the combed sliver is fed into the front roller in a single-sliver feeding manner without sliver doubling; the linear speed of the front roller is controlled at 24m / min to 26m / min, preferably 25m / min.

[0018] Furthermore, in step S4, the spindle speed of the spinning machine is controlled at 950 rpm to 1050 rpm, preferably 1000 rpm, corresponding to the yarn twist being controlled at 35 twists / m to 45 twists / m.

[0019] Furthermore, in step S4, the steel wire traveler is selected with a steel wire traveler that is 3 to 4 sizes larger than that of conventional ring-spun yarn of the same count, in order to match the winding tension of the ultra-coarse yarn and ensure uniform and stable winding.

[0020] The beneficial effects of this invention are as follows: Addressing the technical challenge of consistently producing ultra-coarse pure wool single yarn using traditional ring spinning, this invention achieves efficient and stable production of 0.2 Nm / 1 ultra-coarse pure wool single yarn by modifying the ring spinning machine to eliminate draft, and incorporating a high-quantity combed sliver and near-zero draft twisting process. The total draft ratio is controlled between 0.98 and 1.02 throughout the process, allowing the sliver to maintain its original strip structure before direct twisting into yarn. This completely avoids the compression and friction damage to wool fibers caused by traditional drafting processes, maximizing the preservation of the natural fluffiness, elasticity, and warmth of New Zealand wool, resulting in a uniform yarn structure. The yarn has naturally full hair; at the same time, the equipment modification plan is simple. It can be quickly put into production on the existing ring spinning machine by simply removing the drafting component and adding a low-friction guide strip device. The modification cost is low, the feeding and conveying are stable, and with the optimized matching front roller linear speed, spindle speed, twist parameters and matching wire traveler, the stability of twisting and winding in the undrafted state is effectively guaranteed. Compared with traditional coarse yarn processes such as running spindle spinning, the production efficiency is significantly improved. The final ultra-coarse single yarn has uniform quality and can be widely used in high-end coarse fabrics, decorative fabrics and hand weaving fields, with both good yarn quality and production economic benefits. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those familiar to those skilled in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to this invention. The preferred embodiments and materials described herein are for illustrative purposes only and do not limit the scope of this application.

[0023] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, and the experimental materials used in the following examples are all purchased from commercial channels.

[0024] Example 1

[0025] This embodiment provides a non-drafting processing technology for ultra-coarse single yarns, the specific steps of which are as follows:

[0026] S1. Finishing of wool tops: New Zealand wool combed tops with a fiber diameter of 36μm and a length of 80mm to 110mm are selected as raw materials. The tops are combined and drawn through three needle combing processes to produce combed tops with straight fibers and consistent direction. The weight of the combed tops is controlled to be 5.0g / m.

[0027] S2. Spinning equipment modification: The conventional ring spinning machine is modified to eliminate drafting by removing the middle roller, back roller and apron drafting components, leaving only the front roller as the fiber sliver output and gripping component in the twisting area; a guide device is installed on the feed side of the front roller, and the surface of the guide device is mirror polished to reduce the frictional resistance of the sliver conveying.

[0028] S3. Twisting without drafting: The single combed sliver obtained in step S1 is smoothly conveyed to the front roller nip via the guide device without sliver doubling; the front roller linear speed is controlled at 25m / min, and the total draft ratio of the spinning machine is adjusted to 1.00, so that the sliver maintains its original strip structure and is directly twisted.

[0029] S4. Winding into yarn: Control the spindle speed of the spinning machine to 1000 rpm, corresponding to a yarn twist of 40 twists / m; select a traveler with a specification that is 3 sizes larger than that of conventional ring-spun yarn of the same count, and wind the twisted yarn into shape through the spindle and traveler mechanism to finally produce an ultra-coarse pure wool single yarn with a specification of 0.2 Nm / 1.

[0030] Example 2

[0031] This embodiment provides a non-drafting processing technology for ultra-coarse single yarn, which differs from Embodiment 1 only in the process parameters, as detailed below:

[0032] S1. Refined wool tops: Select New Zealand wool combed tops of the same specification, process them through three combing processes, and obtain combed tops with a yield weight of 4.8g / m.

[0033] S2. Spinning equipment modification: The surface of the guide bar device is treated with polytetrafluoroethylene coating, and the other modification methods are the same as in Example 1.

[0034] S3, No-draft twisting: Single combed sliver is fed in, the front roller linear speed is controlled at 24m / min, and the total draft ratio is 0.98.

[0035] S4. Winding into yarn: Control the spindle speed to 950 rpm, corresponding to a yarn twist of 35 twists / m; select a traveler with a specification that is 4 sizes larger than that of conventional ring-spun yarn of the same count, and wind to produce 0.2 Nm / 1 ultra-coarse single yarn.

[0036] Example 3

[0037] This embodiment provides a non-drafting processing technology for ultra-coarse single yarn, which differs from Embodiment 1 only in the process parameters, as detailed below:

[0038] S1. Refined wool tops: Select New Zealand wool combed tops of the same specification, process them through three combing processes, and obtain combed tops with a yield weight of 5.2g / m.

[0039] S3, No Drafting and Twisting: Single combed sliver is fed in, the front roller linear speed is controlled at 26m / min, and the total draft ratio is 1.02.

[0040] S4. Winding into yarn: Control the spindle speed to 1050 rpm, corresponding to a yarn twist of 45 twists / m; select a traveler with a specification that is 3 sizes larger than that of conventional ring-spun yarn of the same count, and wind to produce 0.2 Nm / 1 ultra-coarse single yarn.

[0041] Comparative Example 1

[0042] This comparative example uses a traditional three-roller double-ring spinning machine to produce the same specification of extra-coarse single yarn, simulating the near-zero draft production state of existing technology:

[0043] Using the same 5.0 g / m combed wool tops as in Example 1, a conventional ring spinning machine without modification was used (retaining the front, middle, and back rollers and the apron drafting system). The total draft ratio was set to 1.00, the front roller linear speed to 25 m / min, the spindle speed to 1000 rpm, the twist to 40 twists / m, and the travelers to be of the same standard and matching specifications. 0.2 Nm / 1 pure wool single yarn was spun.

[0044] Comparative Example 2

[0045] This comparative example uses the traditional spinning process to produce the same specification of extra-coarse single yarn, corresponding to the mainstream replacement process for existing coarse yarn:

[0046] Using the same 5.0 g / m combed wool top as in Example 1, and employing a spinning machine with a yarn twist of 40 twists / m, 0.2 Nm / 1 pure wool single yarn was spun.

[0047] Comparative Example 3

[0048] This comparative example uses the traditional ring spinning plying process to prepare equivalent linear density coarse yarn, corresponding to the existing conventional production path:

[0049] Using the same New Zealand wool raw material as in Example 1, a 0.6 Nm / 1 single yarn was first spun by traditional ring spinning. Then, the three single yarns were combined and twisted through a doubling and twisting process to obtain a three-ply wool yarn with a nominal linear density equivalent to 0.2 Nm and a twist of 30 twists / m.

[0050] Results Analysis

[0051] The yarn samples obtained in Examples 1-3 and Comparative Examples 1-3 were subjected to performance tests. The test items and execution standards are as follows:

[0052] Yarn evenness: The yarn evenness coefficient (CV) was tested using the Uster yarn evenness tester according to GB / T 3292.1-2008.

[0053] Single yarn breaking strength: The single yarn breaking strength was tested using an electronic single yarn strength tester according to GB / T 3916-2013;

[0054] Hairiness performance: The hairiness index of yarns with a length of 3mm and above was tested using a yarn hairiness tester.

[0055] Looseness and elasticity: The compression recovery rate of yarn is tested using a compression elasticity tester, which indirectly characterizes the loft and elasticity retention level of yarn;

[0056] Production efficiency: The yarn output length per spindle per hour is calculated in m / (spindle·h), and the overall efficiency of the entire process is calculated based on the plying process.

[0057] The test results are shown in Table 1.

[0058] Table 1 Comparison of Core Performance Test Results for Each Sample

[0059]

[0060] As can be seen from Table 1:

[0061] (1) The yarn uniformity of each embodiment is significantly superior. The yarn evenness CV values ​​of Examples 1 to 3 are stable at 8.2% to 8.5%, which is much lower than that of Comparative Example 1 (14.7%) with near-zero drafting of traditional ring spinning. This shows that by removing the drafting components, the present invention completely eliminates the problems of insufficient roller holding force and disordered floating fibers at low drafting ratios, and the yarn evenness is greatly improved. It is also superior to running spinning and plying processes, with outstanding uniformity of single yarn structure.

[0062] (2) The natural style of wool is fully preserved. The compression recovery rate of the examples all reached more than 77%, which was significantly higher than that of Comparative Example 1 and Comparative Example 3. This proves that the non-drafting process avoids the damage to the wool scales and fiber structure caused by roller compression and fiber stretching, and preserves the natural fluffy elasticity of wool to the greatest extent. The number of hairs in the examples is moderate and the shape is natural. Compared with the large number of messy hairs generated by the stretching friction in Comparative Example 1, the yarn appearance is fuller and cleaner, which meets the texture requirements of ultra-coarse yarn.

[0063] (3) The yarn strength meets the usage requirements. The single yarn strength of the example is stable at more than 515 cN, which is about 20% higher than that of Comparative Example 1. This is due to the good integrity of fiber length during the non-drafting process and the more uniform cohesion after twisting. Although it is lower than the overall strength of the ply yarn, it fully meets the strength requirements of subsequent weaving, hand weaving and other scenarios.

[0064] (4) Outstanding production efficiency and economy. The production efficiency of the example can reach 22.9 to 24.7 m / (spindle·h), which is comparable to the speed of conventional ring spinning, more than 2.7 times that of running spinning, and far higher than the plying process that requires multiple steps. The advantages of large-scale production are obvious. Moreover, the equipment can be put into production with only simple modification, low modification cost and short production cycle.

[0065] In summary, the process of this invention has successfully achieved the stable preparation of 0.2Nm / 1 ultra-coarse pure wool single yarn, effectively solving the bottlenecks of existing technologies in terms of yarn quality, style preservation, and production efficiency, and demonstrating significant comprehensive performance advantages.

[0066] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0067] The present invention and its embodiments have been described above. This description is not restrictive, and the embodiments shown are only one of the embodiments of the present invention. The actual application is not limited to this. In conclusion, if those skilled in the art are inspired by this description and design similar methods and embodiments without departing from the spirit of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A non-drafting processing technology for ultra-coarse single yarn, characterized in that: Includes the following steps: S1. Finishing of wool tops: 36μm New Zealand wool combed tops are processed by carding, and combed tops are prepared by combining and stretching, controlling the unit length mass of the combed tops to be 4.8g / m~5.2g / m; S2. Spinning equipment modification: The ring spinning machine is de-drafted by removing the middle roller, back roller and apron drafting components, leaving only the front roller as the fiber sliver output and gripping component in the twisting area, and a guide device is installed behind the front roller. S3, Undrafted Twisting: The combed sliver obtained in step S1 is fed to the front roller nip via the guide device. The output speed of the sliver is controlled by the front roller, and twisting is performed under the condition that the total draft ratio of the spinning machine is 0.98 to 1.02, so that the sliver maintains its original strip structure for spinning. S4. Winding into yarn: The yarn obtained in step S3 is wound through a spindle and a wire traveler mechanism to obtain an ultra-coarse single yarn with a specification of 0.2Nm / 1.

2. The non-drafting processing technology for ultra-coarse single yarn according to claim 1, characterized in that: In step S1, the length of the 36μm New Zealand wool fiber is 80mm to 110mm, and the combing process includes three combing steps.

3. The non-drafting processing technology for ultra-coarse single yarn according to claim 1, characterized in that: In step S1, after the combed wool top is processed by a comb, the fiber arrangement direction is consistent, and the output quantity is controlled at 5.0 g / m.

4. The non-drafting processing technology for ultra-coarse single yarn according to claim 1, characterized in that: In step S2, the guide bar device is located on the feed side of the front roller, and the surface of the guide bar device is configured as a mirror polished structure or a polytetrafluoroethylene coating structure.

5. The non-drafting processing technology for ultra-coarse single yarn according to claim 1, characterized in that: In step S3, the combed wool sliver is fed into the front roller in a single-sliver feeding manner, without wool sliver doubling.

6. The non-drafting processing technology for ultra-coarse single yarn according to claim 1, characterized in that: In step S3, the linear speed of the front roller is controlled to be 24 m / min to 26 m / min.

7. The non-drafting processing technology for ultra-coarse single yarn according to claim 6, characterized in that: The linear speed of the front roller is 25 m / min.

8. The non-drafting processing technology for ultra-coarse single yarn according to claim 1, characterized in that: In step S4, the spindle speed of the spinning machine is controlled to be 950 rpm to 1050 rpm.

9. The non-drafting processing technology for ultra-coarse single yarn according to claim 8, characterized in that: The spinning machine spindle speed is 1000 rpm, and the yarn twist is controlled to be 35 twists / m to 45 twists / m.

10. The non-drafting processing technology for ultra-coarse single yarn according to claim 1, characterized in that: In step S4, the steel traveler is selected with a steel traveler that is 3 to 4 sizes larger than that of conventional ring-spun yarn of the same count.

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