Akademik Veri Yönetim Sistemi
9th INTERNATIONAL ISTANBUL SCIENTIFIC RESEARCH CONGRESS, İstanbul, Türkiye, 14 Mayıs 2022, ss.105
In this study, rollers used in sizing and indigo dyeing process of open-end cotton yarns have been
evaluated. Different types of rollers employed in a wide range of applications namely, sheet metal,
paper, textile, and packaging industries. NIP characteristics such as NIP Pressure (N/cm2) and NIP
width (mm) were calculated with NIP Pressure Indicator device and callipers. Experimental results
showed that true roller design selection criterion is bonded with process applied to yarn, squeezing effect
required and pick up ratio that is needed for proper handling of web. Sizing and Slasher indigo dyeing
lines designed according to processes suitable with customer needs. Rollers in creel section are made of
6060-T6 aluminium alloy material with a certain shape which is strong enough and lightweight as well
so that warp can easily rotate roller with the friction created between roller and warp. However, rollers
used in sizing box should be rubber coated for squeezing function of size box, roller diameters are larger
in comparison with creel due the fact that pick-up process requires hyperplastic effect of elastomers
coating to allow absorbing size into fibres. Twin and three high roller combinations positioned on
production line according to function of roller such as drive rollers which are ebonite or chromium
coated, driven rollers which are rubber coated helps to feed web to forward and smaller diameter rollers
for guiding of web. Pressure distribution of squeezing rollers has a critical role on assuring good quality
yarn dyeing, avoiding colour differences along the width of roller. Commonly, final squeezing of
process and heavy load applying rollers are designed and manufactured with a crowned profile. NIP
Pressure measurements of crowned roller profile revealed that side-middle-side differences are less in
comparison with non-crowned rollers