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Differences between Woollen and Worsted Yarn Manufacturing Process

There is a large difference between the spinning and manufacturing process of both woollen and worsted yarn. These are the two different systems through which different grades of yarns are produced from the wool taken from different animals like sheep, alpaca, rabbits, goats and llama.

Differences between Woollen and Worsted Yarn Manufacturing Process

A. Woollen Yarn, Random entanglement of fibers results in a bulky and fuzzy surface of yarn. B. Worsted Yarn, the fibers are lying more parallel and are more tightly twisted resulting in a smooth and finer yarn surface.

The main difference in the spinning of wool yarns comes after scouring process, according to which the woolen and worsted systems are termed.

Woollen yarns are bulkier and coarser giving a thick and full look. The fibers are loosely intertwined, and the yarn has less twists. These yarns are usually made from short staple fibers (1-2 inch) and are used in the manufacturing of thick, heavy and bulkier materials.

On the other hand, worsted yarns are finer, smoother and firmer. The fibers in these yarns are properly and smoothly aligned with each other giving them a thinner look and also enhancing their tensile strength. Usually, long staple fibers (2-15 inch) are used in the manufacturing of worsted yarns. Worsted yarns with less twists are used in knitted fabrics and the yarns with high twists are used in woven fabrics and fine suiting's.

1 Woollen Yarns

In the scouring process most of the oil and grease impurities are removed from the wool fibers. Other impurities like burrs, twigs and vegetable material are destroyed by soaking the wool in dilute sulphuric acid and then heating at high temperature. In this way cellulosic material is destroyed and beaten out of wool. this is also known as Carbonization.

Often, woollen yarns are spun from a mixture of new wool with reclaimed wool, or with rayon, cotton or other fibers. After scouring and cleaning, the wool is blended to mix various grades together and to incorporate any other fibers.

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1.1 Carding

Here the wool is passed through carding machines equipped with rollers covered with sharp steel wires which disentangle the matted fibers. There are usually three parts to the machine used in woollen carding, called the scribbler, intermediate and carder. They all perform in much the same way, separating the fibres and mixing them thoroughly. The wool emerges from the carding machine as a thin blanket of fibers about 1.5m (5 ft) wide, holding together as a fluffy mass.

1.2 Woollen Spinning

The carded wool is then split-up and formed into ribbons which hang together sufficiently to be able to support their own weight. The fibers in the ribbon are in a total disorder state. This ribbon or slubbing is drawn out and spun to form a yarn. Due to the improper arrangement of wool fibers in all directions of the ribbon or slubbing they form bulkier and soft yarns after the twisting or spinning process.

Woollens spun from merino wool are described as saxony woollens; woollens made from cross-bred wools are generally called cheviot woollens.

2 Worsted Yarns

Wool to be spun into woollen yarns may be scoured and dried by commission firms and stored until wanted. It is bought as blends or separate types. But wool for spinning into worsteds is normally scoured and dried immediately before carding.

After drying, the wool is carried straight to the carding machines. The mass of fiber is opened, teased and cleaned, emerging in the usual flimsy sheet. This is brought together to form card slivers which are wound up into balls or allowed to fall into deep cans.

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Unlike woollen yarns, in worsted yarns the carded mass of fibers is first gilled and then combed before the actual spinning process. During these two process the irregular arrangement of wool fibers in the carded mass is turned to a parallel and uniform arrangement, giving the worsted yarns their finer and smooth look. In the combing process short fibers as well as long fibers are combed to give direction and proper alignment to the fibers. This combed wool in the form of an untwisted strand is also known as "top".

2.1 Worsted Spinning

The spinning of worsted yarns is carried out in one of four different ways.

FLYER SPINNING is used with long wools (10O-250mm (4-10 in), mainly 150mm (6 in) fibres, yielding smooth yarns used largely for hosiery.

CAP SPINNING (almost obsolete) is used very largely with botany and fine cross-bred wool. Its production rate is high, and the yarn tends to be hairy.

RING SPINNING has the highest output and is used for making the fine yarns. It now accounts for 80% of the world's spindles.

MULE SPINNING (now obsolete) is used for making continental worsteds, giving a full, soft yarn.

In worsted spinning, 454g (1 lb.) of wool may spin into more than 63,000m (70,000 yd.) of yarn which is made into hard-wearing, high-quality fabrics. The use of expensive raw wools and the number of processes involved in manufacture mean that worsted fabrics are usually high-priced.

As in the case of cotton, the finer wool fibers provide the better-quality yarns and fabrics. Fine fibers can be spun into uniform, smooth yarns that yield firm, lightweight materials which are soft and warm, drape well and retain their shape when made into garments. The long, fine fibers of good quality wool have many more scales per cm than the coarser fibers and are usually more crimped. Worsted yarns made from merino wool are described as botany worsted yarns; worsted yarns made from cross-bred wools are known as cross-bred worsted yarns.

Muhammad Rehan Ashraf

I am a Textile Engineer, founder and editor of "Textile Trendz". Currently working in an export-oriented textile organization. I love to share my knowledge about textiles.