紧密纺纱技术及D型牵伸在苎麻加工中的应用

本文分析了环锭细纱机毛羽的产生,介绍了紧密纺的原理,分析了D型牵伸系统的原理及其在环锭纺细纱机中的应用,紧密纺技术在苎麻纺上应用的可行性.     

紧密纺纱技术在苎麻生产中的应用

本文主要探讨紧密纺技术在苎麻纺织生产中的应用.实践证明,紧密纺纱装置在苎麻生产中能够使苎麻纱线毛羽大幅降低并能改善乌斯特条干各项指标及纱线强力,使苎麻纱线外观质量得到提高.同时提出了目前紧密纺装置在苎麻生产中仍存在的不足及改进建议.     

紧密纺技术在苎麻纺纱中的应用探讨

本文主要探讨紧密纺技术在苎麻纺纱领域中的应用.通过对影响苎麻紧密纺工艺参数的试验研究,以纱线毛羽、断裂强度、乌斯特条干CV值等为考核指标,优选苎麻紧密纺纱工艺.试验结果表明:将紧密纺技术应用于苎麻纺纱中,能较好减少苎麻纱毛羽,提高断裂强度,改善乌斯特条干等纱线品质指标.     

超高支苎麻棉紧密纺纱的开发

优选原料,合理配置混纺工艺,利用可溶维纶短纤提高纺纱支数技术;采用了苎麻、棉、可溶维纶短纤三种性能各异的原料分步均匀、准确混合的"分步混纤"工艺;应用先进的紧密纺技术.成功开发超高支--100sR55/C45苎麻棉紧密纺优质纱.     

嵌入纺在亚麻纺纱中的应用探讨

本文通过对嵌入纺所涉及的长丝张力,长丝和亚麻须条之间的距离,相交角度等分析,探讨嵌入纺技术在亚麻纺纱领域中的应用.实际生产表明,根据亚麻纤维的特点,正确调整相关参数,嵌入式纺纱技术在亚麻纺纱中有着一定的创新性.     

利用新原料和新技术开发麻类（苎麻）新面料

本文对于充分利用目前发展的化纤原料以及新型的纺纱技术和设备，纺制出能克服麻类产品的固有缺陷的混纺纱、复合纱，开发新型麻类面料作了探讨。     

纺纱方式对长绒棉高支纱性能的影响

为明确不同长绒棉纤维适纺性能及不同纺纱方式下的成纱质量，以新疆5个长绒棉品种（系）（新海35号、新海53号、新海57号、丰海8号、丰海7号）的纤维为原料，采用普通环锭纺和紧密纺2种纺纱方式，纺100S纯长绒棉纱，并对成纱性能进行测试。结果：与环锭纺相比，紧密纺大大提高了成纱的强伸性能，降低了3 mm毛羽指数，改善了条干不匀变异系数，其中最为明显的是对3 mm毛羽指数的改善，其次是对强伸性能的改善。可见，紧密纺可较环锭纺提高长绒棉成纱品质，较优的原棉品质对纺纱等后道工序具有很重要的意义。另外，品质指标较优的丰海7号纤维的成纱强伸性能、3 mm毛羽指数、条干不匀变异系数等指标表现较优异。     

苎麻/壳聚糖抗菌纱喷气纺研究

对苎麻/壳聚糖(55/45) 抗菌纱,采用喷气纺纺制的可行性进行了探讨,结果表明通过对喷嘴的设计,选取优化后的工艺参数,同时,喷气纱具有较佳的纱线结构及良好的抗菌性.     

苎麻／壳聚糖抗菌纱喷气纺研究

对苎麻/壳聚糖(55/45)抗菌纱,采用喷气纺纺制的可行性进行了探讨,结果表明:通过对喷嘴的设计,选取优化后的工艺参数,同时,喷气纱具有较佳的纱线结构及良好的抗菌性。     

苎麻牵切纺纱与常规纺纱质量对比

苎麻常规纷纱过程中纤维平均长度为100mm左右,但其中存在着大量的超长、倍长纤维,且纤维长度严重参差不齐,本文对苎麻精干麻进行牵切,得到平均长度为85mm左右、长度整齐度明显改善的牵切苎麻条,并通过生产实践与同一环境下常规苎麻纺的各道工序的质量进行对比分析.     

Analysis of resistance torque on the compact spinning with suction groove

The compact spinning with suction groove can eliminate or decrease the spinning triangle by airflow compacting and shape condensing of the groove, so the yarn hairiness can be reduced effectively for long staple fiber. But the resistance torques produced by the spinning tension and the negative pressure of airflow influence the twist propagation. This paper analyzes variation of the friction coefficient between the fiber bundles and the groove. The transfer process of the moment of the spinning tension and airflow is studied in the variation of the friction coefficient. The expression of the resistance torque is established in the gathering area. The results show that the many factors influence the resistance torque, such as the horizontal friction coeffecient between the fiber bundles and the groove, the spinning tension and the negative pressure, as well as the angle between two suction holes etc. The proper negative pressure and the spinning tension can prevent twist propagation, and can reduce the yarn hairiness and improve the yarn quality.     

Color and whiteness properties of fabrics knitted from different hybrid core-spun yarns containing metal wire

In this study, the color and whiteness properties of fabrics knitted from ring, siro and compact core-spun yarns containing metal wire were investigated. In general, an increase in the metal ratio of yarns causes a decrease in the whiteness and color strengths of fabrics. In our study, spinning method had no statistically significant effect on either the T _w or K/S values of fabrics while the effect of spinning method on the whiteness index of fabrics was briefly observed. Fabrics knitted from siro spun yarns showed higher whiteness properties than those of fabrics knitted from compact and ring spun yarns. This might be explained by the superior covering effectiveness of the siro spinning method on metal wire.     

Study on Spinning triangles in the common ring spinning and Super draft ring spinning systems

In the paper, one kind of super draft ring spinning frame with four drafting rollers and corresponding three drafting zones were introduced. The yarn qualities spun by the super draft ring spinning frame were analyzed by studying the shape of spinning triangles. Using the high speed camera system OLYMPUS i-speed3 and one kind of transparent front top roller, the spinning triangles were captured, and the geometry size of spinning triangle were measured. Then, according to the theoretical model of fiber tension in the spinning triangle, fiber tension distributions in the spinning triangles were presented by using Matlab software. Using the combed roving of 350 tex as raw material, three kinds of cotton yarns, 27.8 tex (21^S), 18.2 tex (32^S) and 14.6 tex (40^S), were spun in the common ring spinning frame with three different suitable spindle speeds, travelers and twist factors. Using the combed roving of 350 tex and 500 tex as raw material, 14.6 tex cotton yarns were spun in the super draft ring spinning frame with three different drafting ratios at back zone. It is shown that with the increasing of spindle speed, a more asymmetric shape of spinning triangle would be produced, and lead to worsen yarn evenness. With the decreasing of traveler weight, the height and horizontal deviation of the spinning triangle is decreased, and may lead to better yarn evenness and less long hairiness. By taking suitable large yarn twist factors, the comprehensive qualities can be improved. Comparing with the common ring spinning, the spinning triangle is larger in the super draft ring spinning. That is, in the super draft ring spinning, the fibers in the strand in the front roller nip are more dispersed, and not benefit for yarn qualities. Therefore, the compact device was introduced into the super draft ring spinning, and the cotton pure yarns and blend yarns were spun, and the yarn qualities were measured and analyzed.     

Comparative study on the characteristics of knitted fabrics made of vortex-spun viscose yarns

Murata vortex spinning system is based on the air jet spinning system. The vast majority of previous works deal with the properties of vortex spun (VS) yarn and the spinning system. In this study, we investigated knitted fabrics from VS yarn in comparison with fabrics from ring (RS), compact (CS) and open-end rotor (OES) spun yarns made from viscose. The effect of yarn spinning system on dimensional and physical properties of knitted fabrics was explained with specific attention to fabrics from VS yarn. Shrinkage of fabrics from VS yarn has the lowest at widthwise direction, while having the highest at lengthwise direction. It is shown that the order of fabric spirality and twist liveliness for yarns from different spinning systems are quite similar. However, relation between loop shape factor and angle of spirality is inconsistent. Angle of spirality of fabrics from VS yarn is higher than fabrics from OES yarn, but lower than that of others. The bursting strength of fabrics from VS yarn is lower than that of those from RS and CS yarns and higher than that of those from OES yarn. From this study, it is also evident that fabrics from VS yarn have the lowest pilling tendency and highest resistance to abrasion.     

Study on characteristics of compact yarns under dynamic state

The dynamic testing conditions simulate actual manufacturing conditions more closely than static testing. In most cases, as results from dynamic tests differ significantly from static tests, dynamic tests are more relevant from the point of view of processing of yarn. The yarns are in motion when they are running on different machines during the production process viz. weaving; knitting etc. Compact ring spun yarns have created a fundamental change how the industry views the ring spinning. The new technology compact yarns such as EliTe® yarns need to be compared with the normal doubled yarns in a dynamic way. This study involves dynamic testing of the EliTe® compact yarns and normal ring spun doubled yarns using CTT (Constant Tension Transport) machine, a versatile test instrument to measure the yarn properties such as dynamic breaking strength, elongation, abrasion, lint, yarn faults (thick, thin places, neps), hairiness etc. EliTe® compact yarns showed higher breaking strength, more elongation, with lesser yarn faults and hairiness, less abrasiveness and less lint generating tendencies during the dynamic testing as compared to the normal ring spun doubled yarns.     

Numerical simulation of fiber strands on condensing effect of suction slot in compact spinning with lattice apron

Compact spinning technology is through the airflow force to get fiber strands to be compacted in the condensing zone. In this paper, it makes a deeper study on the morphological changes and movement process of fiber strands in the flow field of condensing zone. Based on the airflow data in the condensing zone, the geometrical model of single fiber is built, and then the trajectory of single fiber can be got. The difference of trajectory and compact effect of fiber strands is also analyzed in the condensing zone of straight, oblique and deformed suction slots.     

Effect of chemical softening of coconut fibres on structure and properties of its blended yarn with jute

Coconut fibres were subjected to chemical treatment to obtain softer and finer fibres, suitable to blend with other finer fibre like jute. The chemical softening recipe was optimized using Box-Behnken design of experiments as 40 % Na₂S, 10 % NaOH and 6 % Na₂CO₃, which notably reduced the fineness (33 %) and flexural rigidity (74 %) and improved tensile property of coconut fibre. Effect of softening of coconut fibre on its process performance was studied in high speed mechanized spinning system at different blend ratios with jute. Blending with jute assists in spinning of coconut fibre to produce yarn of 520 tex at production rate of 5-6 kg/h, as compared to 15 kg/day for hand spun 5300 tex raw coconut fibre yarn in manual system. Analysis of blended yarn structure in terms of packing density, radial distribution of fiber components (SEM) and mass irregularity were investigated. SEM shows yarns made from softened coconut fibre -jute blends are more compact than raw coconut fibre -jute blend yarns. Coconut fibres were preferentially migrated to core of the yarn. Major yarn properties viz., tensile strength, and flexural rigidity of raw and chemically softened blended yarns were compared against their finest possible 100 % coconut fibre yarn properties. Yarn made up to 50:50 chemically softened coconut fibre-jute blend showed much better spinning performance, and having superior property in terms of reduced diameter, higher compactness, strength, initial modulus and less flexural rigidity than 100 % raw, 100 % chemically softened coconut fibre rope, and raw coconut fibre-jute blend yarns.     

The effect of physical ageing on torque in worsted spun yarns

The intrinsic torque of freshly spun wool yarns is affected by ageing of wool roving prior to spinning as well as the storage time of the yarn after spinning. The effect of physical ageing of roving on yarn torque properties has not been observed before and this study shows that the yarn intrinsic torque increases with ageing of the roving and decreases or relaxes with the yarn storage time. The dependency of the intrinsic torque on the roving ageing time and the yarn storage time after spinning show a simple double-logarithmic shift factor of 0.42 compared with the value of 1 found generally for amorphous polymeric materials. The self-plying twist of the yarns used in this study shows a close link to the intrinsic torque and both are affected by the history of the roving prior to spinning. Significant reductions in the self-plying twist were obtained when deaged rovings were used in spinning. When self-plying twist is used as a predictor of fabric spirality the roving and yarn history needs to be considered. This study shows that low intrinsic torque yarns can be produced by deageing of the roving prior to spinning.     

A study on siro-jet spinning system

Nowadays, there is ever increasing interests regarding with the nozzle usage in spinning systems and also winding process. In this study, an air nozzle was attached on to the sirospun spinning system and the system was called as siro-jet. Sirospun is a spinning system combining spinning and doubling in one operation and a yarn like a two fold is produced. The principle of the siro-jet system is based on the placement of the nozzle at the exit of drafting unit on sirospun spinning system and pressurized air was fed into the nozzle by the compressor during the spinning. In literature, air nozzle application in this manner is not common and hence the system is very less known. For that reason, siro-jet and siropun yarns were produced with different fibre types, material qualities and yarn counts, and the properties of the yarns were compared. At the end of the study, it was determined that siro-jet spinning system truly improves the yarn hairiness in comparison to sirospun spinning system. Even, the siro-jet yarns are less hairy after winding process. Interestingly, hairiness results of siro-jet and sirospun yarns produced with short, non-uniform fibres showed that siro-jet spinning system allows working with low cost raw materials while maintaining yarn quality. Therefore, siro-jet can be considered as an innovative spinning system regarding with less hairy yarn production opportunity.     

Performance of cotton single yarns and knitted fabrics produced by a 2-step spinning method

A low torque spinning method has been recently developed by integrating the ring spinning process with false twisting techniques. As a result of false twist and true twist, a novel single yarn of low torque and soft handle is generated. Based on the similar spinning principle, this paper proposed a 2-step spinning method, which is composed of twisting-anduntwisting operation and can be considered as a variant of the low torque spinning method. The proposed spinning method separates the false twisting process into twisting and untwisting processes which are combined in one step in the low torque spinning method. In this paper, physical properties of yarns produced by the proposed spinning method were evaluated and compared with the conventional yarns. Influences of various spinning parameters on the properties of 2-step yarns were also examined. Furthermore, a systematic study of the physical properties of the 2-step yarns and resultant fabrics with respect to the conventional and low torque ones was carried out. The experimental results showed that the 2-step yarns exhibit slightly higher tenacity, lower wet snarl and much less hairiness than the conventional yarns, which, however, are inferior to the low torque yarns, particularly the evenness. The fabrics made by the 2-step yarns show the softest handle feeling, best airpermeability and moderate spirality angle with acceptable pilling resistance.