الفهرس 
INTRODUCTION AND AIM OF THE WORKOnly 14 pages are availabe for public view
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Abstract
Noise has become one of the most harmful physical sources in the Textile Industry, which is among those industries that are faced with noise exposure problems. Results of sound environmental measurements at modern mills of textile industry have shown that the sound level ranges from 95 to 130 dB, with weaving machines having the highest sound level. Textiles’ insulation materials can be fitted in order to decrease sound pollution at a low cost. As a first step in this research work, a sound insulation simulator was developed and proved to be effective for testing different sound insulators. Kapok fibers, Polyester hollow fibers and wool fibers proved to give better sound sound transmission losss compared to other conventional fibrous materials up to 1600 HZ. Different parameters concerning the materials of the insulators investigated were tested and had significant effects on the increase of sound transmission losses: the use of lycra in knitted fabrics with ratios up to 16%, the increase in the ratio of waste fibers blended with virgin fibers (20 — 40%), adding rubber particles — especially with small particle sizes (size <51.1) as well as changing insulators’ surface topography. The use of melt blown nonwoven fabrics gives better sound transmission losses up to 1600 Hz than knitted and woven fabrics. Different machine parameters for the production of needle punched nonwoven fabrics were also investigated and were proved to have a significant effect on the sound transmission losses of the nonwoven fabrics produced: needle speed, lattice speed and depth penetration. Changing the position of composite material relative to other insulators’ layers was proved to have a significant effect on the sound transmission loss. As a final step, a case study on a ring spinning m/c was performed. Different designs of sound insulators have been tested. Their performance and the increase of the sound insulation properties associated was recorded and analyzed.