This article discussed the structural changes influenced by punching parameters and their impact ... more This article discussed the structural changes influenced by punching parameters and their impact on the functional properties of needle punched nonwoven. Three punching parameters i.e., punch density, needle penetration depth and stroke frequency were considered as process variables. Three factors three levels Box Behnken experimental design was used for sample preparation. Newly proposed structural indices were used to evaluate the fibre orientation in X and Y direction of fabric using tracer fibre technique. It was found that measured functional properties of fabrics are well correlated with considered structural indices. The fibre coverage area inferred an increase but coefficient of fibre curliness and anisotropy of inclination angle of fibre observed a decrease, with the increase of punch density, needle penetration depth and stroke frequency. Mean flow pore size followed an initial decrease and then, increase, but filtration efficiency and pressure drop followed an initial inc...
The ef fects of moist ure content and li near density of feed sliv er on rotor spinning perf orma... more The ef fects of moist ure content and li near density of feed sliv er on rotor spinning perf ormance and yarn qual ity of grey and dyed cotton have been studied. It is observed that the high moisture content in the feed sli ver decreases the end breakage rate of grey cott on, but for dyed cotton the running performance deteriorates wit h the in crease in moisture content. With the in crease in the li near density of feed sliv er, the end-b reakage rate incr eases for both grey and dyed cott on. The yarn quality in terms of esp, irregularity and imperfe ctions, in general, deteriorates with the incr ease in moistur e content and lin ear density of feed sli ver for both grey and dyed cotton. The cotton dyed with natural in digo shows poor running performance and yarn qualit y in comparison to grey and rea ctive black dyed cott on. For all the samples, a heavier sliv er with high level of moisture content produces poor quality of yarn.
Fresh and pollution-free air is very much required to breathe normal and healthy life. However, d... more Fresh and pollution-free air is very much required to breathe normal and healthy life. However, due rise in the usage of automobiles and industrialization, the pollution load is also increasing day by day. Hence efficient filter media is in high demand. In this research, a systematic study was planned and executed for the development of efficient and bio-degradable filter media. A total of five process parameters; carding parameters namely, feeder speed, cylinder speed, and doffer speed, and punching parameters namely punch density and depth of penetration were considered as input parameters were considered and their effect on the physical and functional properties of the final fabric were studied. Forty-six samples were prepared as per 5 factor-3 level Box and Behnken design. The properties such as fabric thickness, tenacity, air permeability, and filtration efficiency were evaluated. Finally, the carding and punching parameters were optimized for achieving the required characteris...
An attempt has been made to study the effect of fibre orientation, measured by the structural cha... more An attempt has been made to study the effect of fibre orientation, measured by the structural characteristics, onmechanical and functional properties of needle-punched nonwoven by varying the carding machine and punchingparameters. It is observed that all measured physical, mechanical and functional properties of nonwovens have strongcorrelation with the proposed structural characteristics. Cylinder speed, punch density and needle depth penetration havesignificant effect on fabric thickness, air permeability, pore diameter, filtration efficiency and pressure drop.
The failure behaviour of polyester/viscose blended ring, rotor and air-jet spun yarns has been st... more The failure behaviour of polyester/viscose blended ring, rotor and air-jet spun yarns has been studied on the basis of fibre failure coefficient, yarn broken end configuration and failure zone length. The failure behaviour of spun yarns under warping process is simulated in the dynamic tensile tester. The tensile failure behaviour of ring, rotor and air-jet yarns are found to be different owing to their difference in fibre consolidation mechanism. The yarn failure is observed to be more and more dominated by fibre slippage once moving from ring to rotor and finally to air-jet yarns. The study also reports mathematical modeling of spun yarn failure behaviour during warping process. The mathematical model indicates that the spun yarn failure is non-linearly related to yarn structural parameters.
Fibre cross-section is an important factor in determining flexural rigidity and elastic recovery ... more Fibre cross-section is an important factor in determining flexural rigidity and elastic recovery of OE rotor-spun yams. The level of spin finish, tex twist factor, draw-off nozzle profile, rotor speed and opening roller speed have profound influence on flexural rigidity. The variation either in twist factor or in rotor speed hardly affects elastic recovery; the elastic recovery, however, increases with the increase in level of spin finish. The increase is highly dependent on the draw-off nozzle profile and opening roller speed.
313-317The effect of fibre-to-fibre friction, roving hank and roving twist multiplier, which dire... more 313-317The effect of fibre-to-fibre friction, roving hank and roving twist multiplier, which directly affect the roving drafting force, on the properties of yarn has been studied. A fairly good correlation (R2 = 0.9001) has been observed between roving strength and drafting force. The yarn tenacity is found to be better correlated with fibre and roving parameters as compared to yarn breaking elongation. Yarn irregularity and total imperfections have very good correlation with the fibre and roving parameters
The nature of fibre migration, the number of fibres in yarn cross-section and the factors that in... more The nature of fibre migration, the number of fibres in yarn cross-section and the factors that influence the strength of rotorand ring-spun yarns have been studied. Rotor yarn comprised 15%less fibres in yarn cross-section than the corresponding ring yarn. Fewer fibres in ~arn cross-section in rotor yarn result in lesser yarn strength. Low values of stress-strain show up the limitation in the spinning of fine counts on a rotor-spinning machine.
A simple nozzle extraction method for measuring objectively the fabric handle has been used. This... more A simple nozzle extraction method for measuring objectively the fabric handle has been used. This method is based on the use of a simple attachment fitted to a tensile testing machine and measures the force generated while extracting a circular fabric specimen through a nozzle. Different testing variables, like presence of supporting plate, extraction speed and shape of the specimen, have significant effect on peak extraction force, whereas the number of pass does not have any specific effect on the extraction behaviour of fabric. Chemical finishing results in reduction in extraction force and at the same time the traverse-at-peak extraction force also reduces with the chemical finish.
An attempt has been made to investigate the filtration behaviour of filter media with gradient st... more An attempt has been made to investigate the filtration behaviour of filter media with gradient structure created through layers of needle punched nonwoven. Batts of different fibre orientation influenced by carding parameters were prepared. Carding parameters i.e. feeder, cylinder and doffer speed were optimized by using response surface methodology to achieve the batts of different fibre orientation. Three batts with a wide range of fibre orientation were selected to create the gradient structures by placing them in a different position in the layered structure. The physical, mechanical and functional properties of nonwoven were evaluated. The different order of fibre orientation of batts was also analysed with the help of SEM images. The fabric with inverse gradient structure having batts in increasing order of fibre orientation in the layered structure provided very high (close to the highest) filter efficiency and very low (close to lowest) pressure drop instead of having higher...
The mechanism of end breakage in ring spinning is a complex phenomenon, and is entirely different... more The mechanism of end breakage in ring spinning is a complex phenomenon, and is entirely different from the yarn failure mechanism during a tensile test. In this paper a possible mechanism of end breakage is reported. A statistical model is developed for predicting the likely end breakage rate in ring spinning. The important factors in governing end breaks are the mean yarn strength, yarn strength variation, mean value of the peak spinning tensions and the variation of yarn mass irregularity. Some practical aspects have also been discussed to tackle the problem of when the breakage rate suddenly increases.
ABSTRACT In the present work, the initiative is being taken to study the spun yarn failure behavi... more ABSTRACT In the present work, the initiative is being taken to study the spun yarn failure behaviour under real dynamic conditions i.e. winding. An attempt is made to study the dynamic failure behaviour of blended ring yarn in relation to yarn structure. Multi-coloured tracer fibre technique is employed to study the broken ends of yarn during the winding process in terms of proportion of fibre break/slip, configuration of yarn broken end and yarn failure length. The ring spun yarn failure during winding is basically dominated by fibre breakage. The length of broken and slipped fibres is found to be different in trailing and leading portion of the broken ends and also depends on viscose content in the blends. The failure zone length and sum of percentage of tapered and slipped broken ends are found to follow the exactly similar trend with fibre failure coefficient with the change in blend ratio. The mathematical model established to explain the spun yarn failure during winding process displays lower error%.
A study of the spinning-in coefficient and critical fiber length ratio in sliver explains the lon... more A study of the spinning-in coefficient and critical fiber length ratio in sliver explains the longitudinal behavior of rotor spun yam. The results show that fiber length and parallelization in rotor spun yarn are inferior to those in feed sliver. Yarn tenacity varies linearly with spinning-in coefficient. The sliver linear density and number of drawframe passages have significant correlations with the spinning-in coefficient and critical fiber length ratio in sliver. Too high an opening roller speed leads to excessive fiber breakage, thus reducing the spinning-in coefficient. Too low a speed, on the other hand, causes a reduced degree of fiber separation and orientation, which also results in a low spinning-in coefficient and hence lower yarn tenacity.
... Although extensive work has been done on a comparison of the properties of yarns (Salhotra, 1... more ... Although extensive work has been done on a comparison of the properties of yarns (Salhotra, 1992; Louis et al., 1985; Padmanabhan, 1989; Barella and Manich, 1989; Krause, 1985; Balasubramanian, 1992 ... The wicking behaviour was studied by using a 2% soap solution. ...
ABSTRACT The effects of ring frame process parameters affecting the packing of yarn, namely yarn ... more ABSTRACT The effects of ring frame process parameters affecting the packing of yarn, namely yarn twist, spindle speed and draft at ring frame, on fabric transmission characteristic have been reported in the present paper. The detailed results on the yarn characteristics and low-stress mechanical properties, due to change of these ring frame parameters, have been reported in Part I of this series. It has been observed that there is very strong evidence that by changing the above ring frame process parameters, which affect the packing factor of yarn, the transmission characteristics of the fabrics can be manipulated. The yarn packing factor is directly related with the yarn diameter. All the studied ring frame process parameters have direct relationship with air permeability, thermal conductivity and relative water vapour permeability, i.e. with the increase in these ring frame parameters the above fabric transmission parameters increase, but water retention characteristics show opposite trend. Thermal absorptivity was found to be related with the fabric surface roughness.
This article discussed the structural changes influenced by punching parameters and their impact ... more This article discussed the structural changes influenced by punching parameters and their impact on the functional properties of needle punched nonwoven. Three punching parameters i.e., punch density, needle penetration depth and stroke frequency were considered as process variables. Three factors three levels Box Behnken experimental design was used for sample preparation. Newly proposed structural indices were used to evaluate the fibre orientation in X and Y direction of fabric using tracer fibre technique. It was found that measured functional properties of fabrics are well correlated with considered structural indices. The fibre coverage area inferred an increase but coefficient of fibre curliness and anisotropy of inclination angle of fibre observed a decrease, with the increase of punch density, needle penetration depth and stroke frequency. Mean flow pore size followed an initial decrease and then, increase, but filtration efficiency and pressure drop followed an initial inc...
The ef fects of moist ure content and li near density of feed sliv er on rotor spinning perf orma... more The ef fects of moist ure content and li near density of feed sliv er on rotor spinning perf ormance and yarn qual ity of grey and dyed cotton have been studied. It is observed that the high moisture content in the feed sli ver decreases the end breakage rate of grey cott on, but for dyed cotton the running performance deteriorates wit h the in crease in moisture content. With the in crease in the li near density of feed sliv er, the end-b reakage rate incr eases for both grey and dyed cott on. The yarn quality in terms of esp, irregularity and imperfe ctions, in general, deteriorates with the incr ease in moistur e content and lin ear density of feed sli ver for both grey and dyed cotton. The cotton dyed with natural in digo shows poor running performance and yarn qualit y in comparison to grey and rea ctive black dyed cott on. For all the samples, a heavier sliv er with high level of moisture content produces poor quality of yarn.
Fresh and pollution-free air is very much required to breathe normal and healthy life. However, d... more Fresh and pollution-free air is very much required to breathe normal and healthy life. However, due rise in the usage of automobiles and industrialization, the pollution load is also increasing day by day. Hence efficient filter media is in high demand. In this research, a systematic study was planned and executed for the development of efficient and bio-degradable filter media. A total of five process parameters; carding parameters namely, feeder speed, cylinder speed, and doffer speed, and punching parameters namely punch density and depth of penetration were considered as input parameters were considered and their effect on the physical and functional properties of the final fabric were studied. Forty-six samples were prepared as per 5 factor-3 level Box and Behnken design. The properties such as fabric thickness, tenacity, air permeability, and filtration efficiency were evaluated. Finally, the carding and punching parameters were optimized for achieving the required characteris...
An attempt has been made to study the effect of fibre orientation, measured by the structural cha... more An attempt has been made to study the effect of fibre orientation, measured by the structural characteristics, onmechanical and functional properties of needle-punched nonwoven by varying the carding machine and punchingparameters. It is observed that all measured physical, mechanical and functional properties of nonwovens have strongcorrelation with the proposed structural characteristics. Cylinder speed, punch density and needle depth penetration havesignificant effect on fabric thickness, air permeability, pore diameter, filtration efficiency and pressure drop.
The failure behaviour of polyester/viscose blended ring, rotor and air-jet spun yarns has been st... more The failure behaviour of polyester/viscose blended ring, rotor and air-jet spun yarns has been studied on the basis of fibre failure coefficient, yarn broken end configuration and failure zone length. The failure behaviour of spun yarns under warping process is simulated in the dynamic tensile tester. The tensile failure behaviour of ring, rotor and air-jet yarns are found to be different owing to their difference in fibre consolidation mechanism. The yarn failure is observed to be more and more dominated by fibre slippage once moving from ring to rotor and finally to air-jet yarns. The study also reports mathematical modeling of spun yarn failure behaviour during warping process. The mathematical model indicates that the spun yarn failure is non-linearly related to yarn structural parameters.
Fibre cross-section is an important factor in determining flexural rigidity and elastic recovery ... more Fibre cross-section is an important factor in determining flexural rigidity and elastic recovery of OE rotor-spun yams. The level of spin finish, tex twist factor, draw-off nozzle profile, rotor speed and opening roller speed have profound influence on flexural rigidity. The variation either in twist factor or in rotor speed hardly affects elastic recovery; the elastic recovery, however, increases with the increase in level of spin finish. The increase is highly dependent on the draw-off nozzle profile and opening roller speed.
313-317The effect of fibre-to-fibre friction, roving hank and roving twist multiplier, which dire... more 313-317The effect of fibre-to-fibre friction, roving hank and roving twist multiplier, which directly affect the roving drafting force, on the properties of yarn has been studied. A fairly good correlation (R2 = 0.9001) has been observed between roving strength and drafting force. The yarn tenacity is found to be better correlated with fibre and roving parameters as compared to yarn breaking elongation. Yarn irregularity and total imperfections have very good correlation with the fibre and roving parameters
The nature of fibre migration, the number of fibres in yarn cross-section and the factors that in... more The nature of fibre migration, the number of fibres in yarn cross-section and the factors that influence the strength of rotorand ring-spun yarns have been studied. Rotor yarn comprised 15%less fibres in yarn cross-section than the corresponding ring yarn. Fewer fibres in ~arn cross-section in rotor yarn result in lesser yarn strength. Low values of stress-strain show up the limitation in the spinning of fine counts on a rotor-spinning machine.
A simple nozzle extraction method for measuring objectively the fabric handle has been used. This... more A simple nozzle extraction method for measuring objectively the fabric handle has been used. This method is based on the use of a simple attachment fitted to a tensile testing machine and measures the force generated while extracting a circular fabric specimen through a nozzle. Different testing variables, like presence of supporting plate, extraction speed and shape of the specimen, have significant effect on peak extraction force, whereas the number of pass does not have any specific effect on the extraction behaviour of fabric. Chemical finishing results in reduction in extraction force and at the same time the traverse-at-peak extraction force also reduces with the chemical finish.
An attempt has been made to investigate the filtration behaviour of filter media with gradient st... more An attempt has been made to investigate the filtration behaviour of filter media with gradient structure created through layers of needle punched nonwoven. Batts of different fibre orientation influenced by carding parameters were prepared. Carding parameters i.e. feeder, cylinder and doffer speed were optimized by using response surface methodology to achieve the batts of different fibre orientation. Three batts with a wide range of fibre orientation were selected to create the gradient structures by placing them in a different position in the layered structure. The physical, mechanical and functional properties of nonwoven were evaluated. The different order of fibre orientation of batts was also analysed with the help of SEM images. The fabric with inverse gradient structure having batts in increasing order of fibre orientation in the layered structure provided very high (close to the highest) filter efficiency and very low (close to lowest) pressure drop instead of having higher...
The mechanism of end breakage in ring spinning is a complex phenomenon, and is entirely different... more The mechanism of end breakage in ring spinning is a complex phenomenon, and is entirely different from the yarn failure mechanism during a tensile test. In this paper a possible mechanism of end breakage is reported. A statistical model is developed for predicting the likely end breakage rate in ring spinning. The important factors in governing end breaks are the mean yarn strength, yarn strength variation, mean value of the peak spinning tensions and the variation of yarn mass irregularity. Some practical aspects have also been discussed to tackle the problem of when the breakage rate suddenly increases.
ABSTRACT In the present work, the initiative is being taken to study the spun yarn failure behavi... more ABSTRACT In the present work, the initiative is being taken to study the spun yarn failure behaviour under real dynamic conditions i.e. winding. An attempt is made to study the dynamic failure behaviour of blended ring yarn in relation to yarn structure. Multi-coloured tracer fibre technique is employed to study the broken ends of yarn during the winding process in terms of proportion of fibre break/slip, configuration of yarn broken end and yarn failure length. The ring spun yarn failure during winding is basically dominated by fibre breakage. The length of broken and slipped fibres is found to be different in trailing and leading portion of the broken ends and also depends on viscose content in the blends. The failure zone length and sum of percentage of tapered and slipped broken ends are found to follow the exactly similar trend with fibre failure coefficient with the change in blend ratio. The mathematical model established to explain the spun yarn failure during winding process displays lower error%.
A study of the spinning-in coefficient and critical fiber length ratio in sliver explains the lon... more A study of the spinning-in coefficient and critical fiber length ratio in sliver explains the longitudinal behavior of rotor spun yam. The results show that fiber length and parallelization in rotor spun yarn are inferior to those in feed sliver. Yarn tenacity varies linearly with spinning-in coefficient. The sliver linear density and number of drawframe passages have significant correlations with the spinning-in coefficient and critical fiber length ratio in sliver. Too high an opening roller speed leads to excessive fiber breakage, thus reducing the spinning-in coefficient. Too low a speed, on the other hand, causes a reduced degree of fiber separation and orientation, which also results in a low spinning-in coefficient and hence lower yarn tenacity.
... Although extensive work has been done on a comparison of the properties of yarns (Salhotra, 1... more ... Although extensive work has been done on a comparison of the properties of yarns (Salhotra, 1992; Louis et al., 1985; Padmanabhan, 1989; Barella and Manich, 1989; Krause, 1985; Balasubramanian, 1992 ... The wicking behaviour was studied by using a 2% soap solution. ...
ABSTRACT The effects of ring frame process parameters affecting the packing of yarn, namely yarn ... more ABSTRACT The effects of ring frame process parameters affecting the packing of yarn, namely yarn twist, spindle speed and draft at ring frame, on fabric transmission characteristic have been reported in the present paper. The detailed results on the yarn characteristics and low-stress mechanical properties, due to change of these ring frame parameters, have been reported in Part I of this series. It has been observed that there is very strong evidence that by changing the above ring frame process parameters, which affect the packing factor of yarn, the transmission characteristics of the fabrics can be manipulated. The yarn packing factor is directly related with the yarn diameter. All the studied ring frame process parameters have direct relationship with air permeability, thermal conductivity and relative water vapour permeability, i.e. with the increase in these ring frame parameters the above fabric transmission parameters increase, but water retention characteristics show opposite trend. Thermal absorptivity was found to be related with the fabric surface roughness.
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