Generally, ring spun yarns are manufactured from roving which is produced by roving frame. In this paper, an experiment has been done producing ring spun cotton yarn directly from finisher drawn sliver eliminatin...Generally, ring spun yarns are manufactured from roving which is produced by roving frame. In this paper, an experiment has been done producing ring spun cotton yarn directly from finisher drawn sliver eliminating the roving frame. Total 3 types of yarn with the various linear density of 8 Ne, 10 Ne & 12 Ne were produced using a roving frame and without using a roving frame. In the next step, physical and mechanical properties of those yarns including unevenness, imperfections, hairiness & tenacity were investigated. The result showed that ring spun cotton yarns produced from sliver exhibited inferior physical and mechanical properties compared with samples from the conventional ring spinning system.展开更多
This study deals with a robot manipulator for yarn bobbin handling in the cotton yarns lattice distortion modification system.The aim is to achieve an operation of yarn bobbin handling with minimal execution time,ener...This study deals with a robot manipulator for yarn bobbin handling in the cotton yarns lattice distortion modification system.The aim is to achieve an operation of yarn bobbin handling with minimal execution time,energy consumption and jerk in motion together.The placement of the robot,in relation to the yarn bobbin stations,is also optimized in conjunction of trajectory optimization.Three possible techniques for building the handling traj'ectory were considered:the quaternion spherical linear interpolation in Cartesian space,the quintic polynomial spline and quintic B-spline in joint space.The genetic algorithm(GA) was used to optimize the trajectories of the robot,with a penalty function to handle nonlinear constraints associated in the robot motion.Two simulations of the optimal trajectory in joint space and the placement of robot were carried out and the results obtained were presented and discussed.It is concluded that the quintic polynomial spline constructs a better trajectory in joint space and the proper placement of robot makes better performance.展开更多
According to the Statistics Center of China National Textile and Apparel Council,inthe first four months of2010,the import of cotton yarn achieved 103085 tons,with
The tensile properties of cotton yarns are studied. A lot of data are gotten and analyzed. It indicates that the breaking strength of the yarns follows Weibull distribution. Then the effect of sample length on strengt...The tensile properties of cotton yarns are studied. A lot of data are gotten and analyzed. It indicates that the breaking strength of the yarns follows Weibull distribution. Then the effect of sample length on strength is analyzed using Weibull's statistics. The Weibull parameters are calculated through regression method.The breaking strength of the yarn at different sample length is predicted. Theoretical prediction conforms the experimental results very well.展开更多
Yarn quality characteristics are affected by processing parameters. A 36 tex rotor spun yarn of 50/50 Basofil/cotton (B/C) blended yarn was spun, and the spinning process optimised for rotor speed, opening roller spee...Yarn quality characteristics are affected by processing parameters. A 36 tex rotor spun yarn of 50/50 Basofil/cotton (B/C) blended yarn was spun, and the spinning process optimised for rotor speed, opening roller speed and twist factor. Selected yarn characteristics were studied during the optimization process. During the optimizations process yarn elongation and hairiness reduced with increase in rotor speed. Tenacity increased with increase of rotor speed. The increase in TF caused tenacity and CV of count to increase up to a peak and then started to decrease with further increase of TF. While TF caused an increase in yarn hairiness, elongation decreased to a minimum level and then started to increase with further increase of TF. CV of count and hairiness increased with increase in opening roller speed, but tenacity and elongation decreased with increase in opening roller speed. The optimization process yielded the optimum levels for rotor speed, opening roller speed and twist factor (TF) as 45,000 rpm, 6,500 rpm and 450 respectively. As per uster Standards the optimum yarn showed good results for CV of count, CV of tenacity and thin places/km.展开更多
The objective of this paper is to establish reliable prediction equations relating cotton fibreproperties measured by HVI system and yarn quality,A useful statistical method is adopted for de-veloping a multiple regre...The objective of this paper is to establish reliable prediction equations relating cotton fibreproperties measured by HVI system and yarn quality,A useful statistical method is adopted for de-veloping a multiple regression model interpreting the relation between the data of Spinlab HVIfibre properties and quality parameters of yarn STQ (Strength Tex Quotient).The percent relativecontribution of a fibre property with respect of STQ is also assessed.The results show that the totalcontribution of the HVI measured fibre properties can account for 77.4% of known variation ofyarn STQ.The main feature of the approach is its flexibility in accommodating all fibre properties.The examination of regression equation showed that it could be well applied to predict STQ ofyarns spun from the same spinning system,but,for different spinning systems and also for yarns ofdifferent linear density,modification of the equation would be needed.展开更多
Cotton,a hydrofilic textile fiber,has unstable characteristics and,for this reason,it varies its properties according to the environment changes.Moisture and temperature are the two most important factors that lead to...Cotton,a hydrofilic textile fiber,has unstable characteristics and,for this reason,it varies its properties according to the environment changes.Moisture and temperature are the two most important factors that lead to a cotton spinning sector and influence its quality.Those two properties can change the entire spinning process.Understanding this,moisture and temperature must be kept under control when used during the spinning process,once the environment is hot and dry,the cotton yarns absorb moisture and lose the minimal consistency.According to this information,this paper was developed testing four types of cotton yarns,one kind of cotton from Brazil and the others from Egypt.The yarns were exposed to different temperatures and moisture in five different tests and in each test,six samples were examined through physical and mechanical tests:resistance,strength,tenacity,yarn’s hairness,yarn’s evenness and yarn’s twisting.All the analyses were accomplished at Laboratório de Mecânica dos Fluidos and at COATS Corrente S.A.,where,it was possible to use the equipments which were fundamental to develop this paper,such as the STATIMAT ME that measures strength,tenacity,Zweigler G566 that measure hairiness in the yarn,a skein machine and a twisting machine.The analysis revealed alterations in the yarn’s characteristics in a direct way,for example,as moisture and temperature were increased,the yarn’s strength,tenacity and hairness were increased as well.Having the results of all analysis,it is possible to say that with a relatively low temperature and a high humidity,cotton yarns have the best performance.展开更多
文摘Generally, ring spun yarns are manufactured from roving which is produced by roving frame. In this paper, an experiment has been done producing ring spun cotton yarn directly from finisher drawn sliver eliminating the roving frame. Total 3 types of yarn with the various linear density of 8 Ne, 10 Ne & 12 Ne were produced using a roving frame and without using a roving frame. In the next step, physical and mechanical properties of those yarns including unevenness, imperfections, hairiness & tenacity were investigated. The result showed that ring spun cotton yarns produced from sliver exhibited inferior physical and mechanical properties compared with samples from the conventional ring spinning system.
基金National Key Technology Support Program,China(No.2012BAF13B03)Program for Changjiang Scholars and Innovative Research Team in University,China(No.IRT1220)
文摘This study deals with a robot manipulator for yarn bobbin handling in the cotton yarns lattice distortion modification system.The aim is to achieve an operation of yarn bobbin handling with minimal execution time,energy consumption and jerk in motion together.The placement of the robot,in relation to the yarn bobbin stations,is also optimized in conjunction of trajectory optimization.Three possible techniques for building the handling traj'ectory were considered:the quaternion spherical linear interpolation in Cartesian space,the quintic polynomial spline and quintic B-spline in joint space.The genetic algorithm(GA) was used to optimize the trajectories of the robot,with a penalty function to handle nonlinear constraints associated in the robot motion.Two simulations of the optimal trajectory in joint space and the placement of robot were carried out and the results obtained were presented and discussed.It is concluded that the quintic polynomial spline constructs a better trajectory in joint space and the proper placement of robot makes better performance.
文摘According to the Statistics Center of China National Textile and Apparel Council,inthe first four months of2010,the import of cotton yarn achieved 103085 tons,with
文摘The tensile properties of cotton yarns are studied. A lot of data are gotten and analyzed. It indicates that the breaking strength of the yarns follows Weibull distribution. Then the effect of sample length on strength is analyzed using Weibull's statistics. The Weibull parameters are calculated through regression method.The breaking strength of the yarn at different sample length is predicted. Theoretical prediction conforms the experimental results very well.
文摘Yarn quality characteristics are affected by processing parameters. A 36 tex rotor spun yarn of 50/50 Basofil/cotton (B/C) blended yarn was spun, and the spinning process optimised for rotor speed, opening roller speed and twist factor. Selected yarn characteristics were studied during the optimization process. During the optimizations process yarn elongation and hairiness reduced with increase in rotor speed. Tenacity increased with increase of rotor speed. The increase in TF caused tenacity and CV of count to increase up to a peak and then started to decrease with further increase of TF. While TF caused an increase in yarn hairiness, elongation decreased to a minimum level and then started to increase with further increase of TF. CV of count and hairiness increased with increase in opening roller speed, but tenacity and elongation decreased with increase in opening roller speed. The optimization process yielded the optimum levels for rotor speed, opening roller speed and twist factor (TF) as 45,000 rpm, 6,500 rpm and 450 respectively. As per uster Standards the optimum yarn showed good results for CV of count, CV of tenacity and thin places/km.
文摘The objective of this paper is to establish reliable prediction equations relating cotton fibreproperties measured by HVI system and yarn quality,A useful statistical method is adopted for de-veloping a multiple regression model interpreting the relation between the data of Spinlab HVIfibre properties and quality parameters of yarn STQ (Strength Tex Quotient).The percent relativecontribution of a fibre property with respect of STQ is also assessed.The results show that the totalcontribution of the HVI measured fibre properties can account for 77.4% of known variation ofyarn STQ.The main feature of the approach is its flexibility in accommodating all fibre properties.The examination of regression equation showed that it could be well applied to predict STQ ofyarns spun from the same spinning system,but,for different spinning systems and also for yarns ofdifferent linear density,modification of the equation would be needed.
文摘Cotton,a hydrofilic textile fiber,has unstable characteristics and,for this reason,it varies its properties according to the environment changes.Moisture and temperature are the two most important factors that lead to a cotton spinning sector and influence its quality.Those two properties can change the entire spinning process.Understanding this,moisture and temperature must be kept under control when used during the spinning process,once the environment is hot and dry,the cotton yarns absorb moisture and lose the minimal consistency.According to this information,this paper was developed testing four types of cotton yarns,one kind of cotton from Brazil and the others from Egypt.The yarns were exposed to different temperatures and moisture in five different tests and in each test,six samples were examined through physical and mechanical tests:resistance,strength,tenacity,yarn’s hairness,yarn’s evenness and yarn’s twisting.All the analyses were accomplished at Laboratório de Mecânica dos Fluidos and at COATS Corrente S.A.,where,it was possible to use the equipments which were fundamental to develop this paper,such as the STATIMAT ME that measures strength,tenacity,Zweigler G566 that measure hairiness in the yarn,a skein machine and a twisting machine.The analysis revealed alterations in the yarn’s characteristics in a direct way,for example,as moisture and temperature were increased,the yarn’s strength,tenacity and hairness were increased as well.Having the results of all analysis,it is possible to say that with a relatively low temperature and a high humidity,cotton yarns have the best performance.
