Sound Absorption of Tufted Carpets Produced from Coarse Wool of Mountain Sheep

Abstract

Coarse wool from Polish mountain sheep, often treated as a useless by-product of sheep husbandry, was used to produce pile carpets with tufting technique. Raw wool was used in the small-scale spinning mill to spin prototype rug yarns, which were then used for the production of carpets. The carpets with cut and loop piles of two different heights and densities were manufactured. During examinations, the basic parameters of raw wool, yarns, and tufted fabrics were determined. Then, the soundproofing properties of carpets were analyzed. To characterize the acoustic properties of the carpets, the sound absorption coefficient and transmission loss were measured. The measurements were carried out in one-third octave bands in the frequency range of 80–5000 Hz using the impedance tube method. It was stated that the wool of Polish mountain sheep is coarse, highly differentiated both in thickness and length and contains a significant content of medullated fibers and kemp. Despite its poor characteristics, the wool can be used for the production of rag yarns suitable for the production of pile carpets with tufting technique. The carpets possess acceptable sound absorbing capacity comparable to other similar products obtained from other wool types, which is dependent on both pile types and their parameters. The carpets exhibit low transmission loss, which is influenced, to a lesser extent, by the change in the parameters of the pile layer.

Keywords

• sheep wool
• yarn
• carpet
• tufting
• acoustic properties
• sound absorption
• transmission loss