Manufacturing of Worsted and Woolen Yarns

Manufacturing of Worsted and Woolen Yarns

Worsted Yarns:

In the manufacturing of worsted yarns following steps are carried out

• Carding
• Gilling and combing
• Drawing
• Roving formation
• Spinning
• Worsted yarns are obtained.

A short description of the above process is given below:

Carding:

The main objective of carding is to disentangle the fibers, in the process the fibers are laid in parallel manner. The fibers are passed through rollers which are covered with fine layer of teeth. As soon as the carding is carried out the fibers are directed to the gilling and the combing operation.

Gilling and combing operations:

There are two gilling operations provided, one before preparatory and one after combing. The function of preparatory gilling is to align the fibers in parallel fashion and further blend the wool through doubling and to add moisture and lubricants.

The finishing gilling operation aims to remove mild entanglement introduced to the combed sliver. The carded wool, which is to be made into worsted yarn, is put through gilling and combing procedure. The gilling process removes the shorter staple fibers and straightens the longer fibers.

This process is continued, in the combing operations, which removes short fibers which are called as comber noils, places the longer fibers which are called as tops, parallel and further cleans the fibers by removing any remaining impurities.

Drawing:

Drawing is an advanced operation which involves doubling of sliver of wool fibers. The process draws, drafts, twists, winds the stock making the sliver more compact and thinning them into slubbers. Drawing is only done for worsted yarns.

Roving:

This is the final stage before spinning. Roving is actually involves a light twisting operation which is carried out to hold the thin slubber intact.

Spinning of Worsted yarn:

The same type of spinning applicable for both woolen and worsted yarn. In the spinning operation the wool roving is drawn out and twisted into the yarn. There are two main methods to produced woolen spun and worsted spun yarn is Ring and Mule spinning.

Mule spinning:

Mule spun yarns are superior to ring spun yarn but they are more expensive due to the slow production rates and high labor input.

Worsted yarns are spun on any kind of spinning machine, Mule, Ring, Cop or flyer. The two principle system of spinning worsted yarns is English and French system. In English system, the fiber is oiled before the combing which inserts a tight twist. In the French system, oil is not used and yarn is not given any twist. Thus, yarn obtained by this process is fuzzy.

Manufacturing of Woolen Yarn:

• In manufacturing of woolen yarn, the fibers are passed through two stages, carding and spinning.
• The objective of the carding process is to disentangle the fibers, during this process the wool fibers are passed through rollers which are covered with thousands of wire like teethes. With the help of these wires the fibers are arranged in parallel manner, this makes the woolen yarn smooth.
• By the help of oscillating device, one thin film or sliver of wool is placed diagonally and overlapping another sliver to give a criss-cross effect to the fiber.

Difference between Woolen yarn and Worsted

• The Woolen yarn is medium or coarser in diameter than the worsted yarn which is finer in diameter. The woolen yarn is spun from short fibers which are 1-3 inches where as the worsted yarns are spun with longer fibers which are above 3 inches. Woolen yarns are bulky in nature and the worsted yarns are fine and smooth.
• During woolen yarn processing, the fibers are washed, scoured and carded and in worsted yarn processing the fibers are washed, scoured, carded and them combed and drawn. Woolen yarns have low to medium slack twist which results in low twist. The worsted yarns have tighter twist giving them high tensile strength.
• The fabric produced by woolen yarn is soft in feel and fuzzy and posses heavy weight the fabric produced by worsted yarn is smooth and has crisp with lighter in weight. Woolen yarns are good insulator due to the trapped air, where as the worsted yarns are not good insulator.
• The woolen yarn fabrics do not hold the crease well and are less durable than worsted yarns. On the other hand, the woolen fabrics hold creases and shape well and are more durable. Woolen spun yarns are in the production of sweaters, carpets, tweeds.  Worsted spun yarns are used in preparation of suits, dresses, crepes.