NOPR Collection:

Quality testing of staple yarn by an instrument with dual sensing and its comparative study with capacitive sensing

Sat, 01 Sep 2018 00:00:00 GMT

Title: Quality testing of staple yarn by an instrument with dual sensing and its comparative study with capacitive sensing Authors: Roy, Subhasish; Sengupta, Anindita; Sengupta, Surajit Abstract: An instrument employing both image processing and optical sensing in a single run has been developed to evaluate yarn quality parameters such as irregularity, imperfections and hairiness. Dedicated software, inbuilt within the system, is also developed, which measures the attributes from both the sensors, and a best fit representation is made. The irregularity and imperfections obtained from proposed instrument are compared with those obtained from universally accepted capacitive sensing Uster tester, whereas hairs/meter are compared with Zweigle tester. The cotton, cotton-polyester blended and jute yarns have been tested in all the systems. The repeatability and reliability of results in both image processing and optical sensing are found insignificant in 5% confidence level. It is observed that the yarns with diameter value up to 0.65 mm can be evaluated by optical sensor, but above this threshold, image processing may be done successfully. Uster tester result mostly corroborates with image processing. Optical sensor shows higher values than image processing. Page(s): 269-276

Prediction of open-hole tensile strength of unidirectional flax yarn reinforced polypropylene composite by analytical and numerical models

Sat, 01 Sep 2018 00:00:00 GMT

Title: Prediction of open-hole tensile strength of unidirectional flax yarn reinforced polypropylene composite by analytical and numerical models Authors: Kannan, T Gobi; Pawar, S J; Cheng, Kuo Bing Abstract: Open-hole tensile strength of unidirectional flax yarn reinforced polypropylene composites has been predicted for different laminates with varying lay-up through analytical and numerical models. Point stress criterion (PSC), modified PSC and finite element modeling (FEM) have been applied to examine the effect of different open-hole sizes on the stress bearing capacity. The characteristic length (d₀) of the composites has been confirmed by PSC which depends on the specimen geometry. The modified PSC has been used with stress concentration factor, notch sensitivity factor, and exponential parameter for evaluating the open-hole tensile strength. The stress distribution and the open-hole tensile strength have also been obtained by finite element simulation. The best correlations between the experimental and predicted results have been achieved from modified PSC model than with traditional PSC and FEM models. Page(s): 277-284

Electroneutral quaternization and sulfosuccination of cornstarch for improving the properties of its low-temperature sizing to viscose yarns

Sat, 01 Sep 2018 00:00:00 GMT

Title: Electroneutral quaternization and sulfosuccination of cornstarch for improving the properties of its low-temperature sizing to viscose yarns Authors: Li, Wei; Zhu, Zhifeng; Wang, Xu; Xu, Zhenzhen; Liu, Xinhua Abstract: The objective of this work is to evaluate the influences of electroneutral quaternization and sulfosuccination (electroneutral QS) on the adhesion of starch to viscose fibres and sizing properties of starch to viscose yarns at low temperature in order to study if the derivatization can improve the serviceability of starch applied for sizing viscose yarns at low temperature. The quaternized and sulfosuccinylated starch (QSS) with electroneutrality has been synthesized in aqueous dispersion by a quaternization of hydrolyzed cornstarch (HS) with N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride and a further sulfosuccination is done for introducing a fixed mole ratio of 3-(trimethylammonium chloride)-2-hydroxypropyl (TACHP) substituents to sulfosuccinate (SS) substituents onto starch chains. It is found that electroneutral QS is available to ameliorate the adhesion at different temperatures. The amelioration in the adhesion depends on the level of the modification. In addition, the modification improves the mechanical properties of the sized viscose yarns, and decreases hairiness of sized yarns, even if the temperature of the electroneutral QSS paste is lowered to 60 °C. Electroneutral QSS with a degree of substitution of 0.0438 is expected to show a potential application in sizing viscose yarns at 60 °C. Page(s): 285-294

Effect of spinning process parameters on mélange yarn quality by Taguchi experimental design

Sat, 01 Sep 2018 00:00:00 GMT

Title: Effect of spinning process parameters on mélange yarn quality by Taguchi experimental design Authors: Ray, Suchibrata; Ghosh, Anindya; Banerjee, Debamalya Abstract: The important yarn quality parameters, like evenness, imperfection, hairiness, strength and breaking elongation percentage, of blow-room blended cotton mélange yarn have been studied using Taguchi experimental design. The impacts of process parameters, such as shade depth (%), twist multiplier and ring frame spindle speed, have been studied in presence of two unavoidable and uncontrolled noise parameters. The experimental results show that the mélange yarn quality parameters are significantly affected by shade depth and ring frame spindle speed. A ranking of the three controlled parameters and the percentage contribution of each of these parameters have also been evaluated. The shade depth is found most dominating factor affecting cotton mélange yarn quality. The set of optimum parameters that correspond to the highest S/N ratio of evenness, imperfections, hairiness, strength and breaking elongation percentage have also been determined. Page(s): 295-300