Download Premier Intelligence Book on Hair Severity (5.51MB) Hair Severity – A new Yarn Hairiness parameter Hairiness is a key parameter that affects the yarn and degrades the fabric appearance. The conventional Hairiness Index (HI) measurement provides only a single average value of hairs, giving no indication of hair length distribution. Hair count (H3), is a cumulative value (3-10mm) of hair length distribution involving a complex procedure to analyze the measurement. Hair Severity (HS), a new yarn hairiness parameter from Premier represents the severity of the long length hairs. Two yarn samples with similar HI values will have different HS value based on the hairs distribution. HS can be used as an excellent process control tool for spinners and yarn buyers. Sample HI HS A 4.46 8.9 B 4.53 11.5 HS shows a hairiness difference of ~ 30% between the two samples as against ~ 1.5% for HI HS Statistics 2007: A benchmark for yarn hairiness The HS Statistics 2007 serves as benchmark for mills in controlling the yarn hairiness. The statistics have been arrived at from the samples collected across the globe (South East Asia, South Asia, Latin America and the Middle East). HS values have been plotted against four different count and material.  40s CHY Level HI H3 HS 5% 4.96 107.4 6.6 25% 4.71 189.5 11.5 50% 4.0 231.9 14.2 HS shows a good co-relation with key raw material characteristics HS shows a good co-relation and trend with critical raw material characteristics like Uniformity Index (UI), Micronaire (Mic) and Short Fibre Index (SFI). As an example, it has been identified that Lower the UI, higher will be the HS. Coarser Mic leads to a higher HS. Lower the SFI, lower is the HS. HS is a significant indicator for critical process parameters HS is influenced by several process parameters in preparatory and spinning. HS shows a good trend for critical quality parameters like the True Short Fibre (TSFn) in the Draw Frame, spindle speed and the spacer size in the Ring Frame. HS thus acts as an intelligent indicator of the process condition. HS is a very useful tool in the selection of Ring traveler, Ring life, Optimization of spacer size and the twist level in the Ring Frame. Spinners can also benefit by using the HS in arriving at the winding tension and an optimal wax selection. Optimization of spacer size Nec Size(mm) HI HS 40 CHY 3.00 4.86 26.4 3.25 4.73 20.5 3.50 4.62 23.2 HS helps in the right selection of yarn for a superior Knitting/Weaving performance Controlled studies have been carried out to identify the effect of HS on knitting and weaving performance on circular knitting machine and Projectile weaving machines using identical samples from different sources. HS influences pilling effect in knits. The end breaks in knitting are due to the Fluff accumulation at the slub catcher due to protruding hairs. Knitting performance Sample HI HS Average Yarn Breaks/hour A 7.8 151.8 14 B 7.5 106.7 7 HS truly reflects the extent of yarn breaks in knitting and weaving as against the conventional measurement of HI. The weaving results (of 60x60 used as bed linen fabrics) reveal most projectile cuts are due to high HS values Weaving performance Sample Yarn Hairiness Total Warp Breaks per 100,000 picks Projectile cuts due to Hairiness per 100,000 picks Percentage Contribution HI HS       A 4.88 37.0 13.8 6.2 45.2 B 4.63 29.2 4.9 0.4 9.0 Premier recommends the use of HS during selection of the Raw material, Optimization of the process parameters and during yarn selection for improvement of knitting and weaving performance.