A Report on Wool and Its Manufacturing

Wool is the most important natural fiber in the world, which is sheared from the sheep or goat and chiefly composed of the animal protein. The properties of wool fiber include good elasticity, low abrasion resistance. In addition, it is very comfortable and attacked by moths. Also, wool fiber has been using in the production of clothing, such as making suits, dresses, coats, and carpets.

Manufacturing countries of the wool material According to the most recent available figures of the International Wool Textile Organisation, around 1.155 million kg of clean raw wool are produced in 20183. Although wool is produced in more than 100 countries around the world, more than 90% of the wool in the global textile market is produced by the following 11 largest wool producing countries. According to the International Wool Textile Organisation, Australia, China, the US, New Zealand, and Argentina are the top wool manufacturing countries of the world. Australia is the country with the highest wool production in the world, which is responsible for the production of 25% of the world's wool. There are approximately 70 million sheep in Australia, producing an average of 4.6kg of wool per head, and a total wool yield of 340 million kilograms greasy. Having a high number of sheep bred, the industries of Australia can produce a high number of wool. In recent years, the annual wool production of Australia has remained at 330,000 tons. China is the second largest wool producer in the world, which produces around 160,000 tons of wool per year. The United States produced 25.7 million pounds of wool. The fourth largest wool producer in the world is New Zealand, which manufactures 11% of the world's wool. The fifth largest wool manufacturing country is Argentina, which produces 3% of the world's wool. The comparison between the greasy wool and the worsted yarn Wool is obtained by shearing the fleece off the sheep’s back once a year, that requires to undergo a series of procedure to transform into a useful yarn. Besides, greasy wool is the raw material form of wool, while worsted yarn is in the form of spun yarn. There are three differences between greasy wool and worsted yarn.

Firstly, the composition of greasy wool contains some impurities, while worsted yarn is without any impurities. Greasy wool is sheared from the sheep that have not process any steps to remove the impurities such as wool grease, sweat and dirt from the wool. Therefore, greasy wool may include some ingredient like suint, vegetable matter, and other ointments. On the contrary, having done the general procedures to transform into a spun yarn, worsted yarn is more clear and purer than the greasy wool.

Secondly, the other differences between greasy wool and worsted yarn is the structure. The worsted spun yarn is formed after the twist enters straightened and parallel fibers. With less trapped air between fibers, worsted yarn will tend to be heavy. On the contrary, the greasy wool will not do any twist processing and this will result in the fact that the greasy wool will purposefully trap more air, and therefore be far more bouncy and light. Also, the fiber length of greasy wool depends on the growth rate which depends on genetic and environmental factors, while the length of the worsted yarn depends on the spinning process.

However, the fiber surface structure of greasy wool and worsted yarn is the same. Both of them are made from the wool fibers which contain different lengths from 0-1 millimeter to more than 10 millimeters. Each fiber is covered with overlapping scales, but is not twisted. It is curled or wavy.

Apart from the structure of the greasy wool and the worsted yarn, the appearance of fiber is also another difference between greasy wool and worsted yarn. Hairiness is a property that indicates the amount and length of fiber ends and loops protruding from the body of the yarn. Worsted spun yarn will have low hairiness, because the shorter fibers have been removed during combing, before they were spun into yarn, and the longer fibers have been organized. On the contrary, greasy wool has a high hairiness since it will not have any combing process. With less hairiness of the worsted spun yarn, greasy wool is less sturdy than the worsted spun yarn.

To transform the raw material of greasy wool to the worsted spun yarn, there are four solutions to the production which include scouring, carbonizing, gilling and combing. For the fiber composition, the principal objectives of wool scouring are to remove all wool contaminants like grease, sweat and dirt from the greasy wool at maximum efficiency, with efficient energy utilization. Scouring conditions are designed to obtain maximum cleaning without felting and minimum impact on the environment. However, scouring does not remove the bulk of vegetable matters, such as burrs, seeds and straw, which tend to remain trapped in the fibers.

For the structure, paralleled and uniformed fiber structures are more suitable for the convert of yarn. During the drafting process, the sliver fibers through a series of rollers to straighten the individual fibers and making them more parallel. However, longer fiber in greasy wool may require pins to prevent entanglement and irregular movement of fibers during drafting. Besides, the gilling can help to improve the regularity of sliver fibers, straighten and parallelize fiber and mix of fibers. Therefore, with less trapped air between fibers, the yarn will tend to be heavy.

Furthermore, the combing process can help improve the appearance of fiber. The combing process can remove the short fibers and vegetable matters as well as complete the fiber alignment process in preparation for spinning. Consequently, the fibre can become less hairiness, more neat and smooth appearance.