Worsted Yarns





=Carding.= After the wool is washed it undergoes a number of

operations before it is finished into worsted or woolen yarn.[12] The

first step in the manufacturing of worsted yarn is to pass the washed

wool through a worsted card which consists of a number of cylinders

covered with fine wire teeth mounted on a frame. The effect of these

cylinders on the wool is to disengage the wool fibers, make them

straight, and form a "sliver" or strand. It is now ready for the

combing machine.



=Combing.= The process of combing consists of subjecting the card

sliver to the operations of the automatic wool comber, which

straightens the fibers and removes all short and tufted pieces of

wool. Combing is a guarantee that every fiber of the wool lies

perfectly straight, and that all fibers follow one after the other in

regular order.



=Comb.= A comb is a complicated machine. The principal feature is a

large metal ring with rows of fine steel pins (pin circles), which is

made to revolve horizontally within the machine. By various devices

the wool is fed into the teeth of the ring in the form of tufts. The

fibers of the tufts by an intricate process are separated into long

and short lengths, and a set of rollers draws each out separately and

winds it into a continuous strand called "tops." On leaving the

comber, the wool is free from short fibers, specks, and foreign

substances, and presents a fine, flowing, and lustrous appearance. The

short combed-out wool is called noils, and is used in making carpet

yarns, ground up into shoddy stock, or utilized in spinning fancy

yarns.



=Worsted Tops.= American textile manufacturers are finding it

advantageous to have their combing done by those who make the work a

specialty rather than to do it themselves. In the manufacture of tops

all varieties of combing wools are used: Australian, Merino, and

Crossbred wools, South American Merino and Crossbred wools, Cape

Merino wools, Merino and Crossbred wools grown in the United States,

the lustrous wools of pure English blood, Mohair from Asiatic Turkey,

and Alpaca from the Andes. Tops are sold to worsted spinneries.[13]

Many mills or worsted spinneries send their wools, either sorted or

unsorted as they may desire, to a combing mill, where the wool is put

into top at a lower price than that at which most spinneries can do

their own combing. By means of the naphtha process a larger amount of

top from a given amount of wool can be secured than by any other

process, and in addition, a top in better condition for drawing and

spinning.





In a strand of combed wool, called top, no single fiber lies across

the strand; all lie in the direction of the length. This order is

preserved until the fibers have been converted into yarn, which is

accomplished by passing through "gill boxes." These gill boxes are

machines with bars of iron having upon their surface two rows of

minute steel pins, by this means kept perfectly straight. The bars on

which they are placed are worked on screws between two sets of

rollers. The wool enters between the first set of rollers, and, as it

passes through, is caught by one of these gills that is raised up for

the purpose, being succeeded by others as the rollers revolve. These

gills are moved forward on screws in the direction of the other set of

rollers, and the pins in the gills always keep the fiber perfectly

straight. The second set of rollers is termed the draught rollers,

since by them the wool, after passing through the front rollers, is

drawn out and reduced in thickness. This is accomplished because the

second rollers revolve at a higher rate of speed than the first

rollers, the speed being regulated according to the length of the

wool, and the thickness of the yarn to be produced. These gills are

used in the production of worsted yarn until the size of the rope of

wool has been so reduced and twisted that there is no chance of any

fiber getting crossed or out of the order of straightness. A worsted

yarn is, consequently, a straight yarn, or a yarn produced from

perfectly straight fibers.





The combing of wool may be dispensed with in some cases, although

such a yarn is not in common use. When combing is dispensed with, the

gills, in connection with the draught of the rollers, make the fibers

straight, and produce a worsted yarn, although such a yarn has a

tendency to be uneven and knotty.



Before the wool can be spun it must be made into roving of a suitable

thickness. This is done by passing it, after being combed, through a

series of operations termed drawing, whose functions are to produce a

gradual reduction in thickness at each stage. Although the number of

machines varies according to the kind of wool to be treated, still the

same principle applies to all.



=Spinning.= The process of spinning is the last in the formation of

yarn or thread, the subsequent operations having for their object the

strengthening of the yarn by combining two or more strands and

afterward arranging them for weaving or for the purpose for which the

yarn is required. It is also the last time that the fibers are

mechanically drawn over each other or drafted, and this is invariably

done from a single roving. The humidity and temperature of the

spinning room must be adjusted to conditions. Each spinner is provided

with a wet and dry thermometer so that the best temperature can be

ascertained. The most suitable heat and humidity can only be obtained

by comparison and observation. A dry and warm atmosphere causes the

wool to become charged with electricity and then the fibers repel each

other.



Worsted yarn is spun by two different methods known respectively as

the Bradford or English system and the French system. The difference

in these systems of spinning worsteds lies principally in the drawing

and spinning processes, a radically different class of machinery being

used for each. The combing process is practically the same in both

cases, but the wool is combed dry for the French system, and by the

English method the stock is thoroughly oiled before being combed. The

result of the English method is the production of a smooth level yarn

in which the fibers lie nearly parallel to each other. The yarn made

according to the French system is somewhat fuzzier and more woolly. On

account of the absence of oil, the shrinkage of French spun worsted is

considerably less than that made by the Bradford system.



=Characteristics of Worsted Yarn.= The unique structure of worsted

yarn makes it invaluable in the production of textile fabrics in which

luster and uniformity of surface are the chief characteristics. The

methods by which worsted is formed render it capable of sustaining

more tension in proportion to its size than the pure woolen yarn. This

feature, combined with its lustrous quality, gives it a pre-eminent

position in the manufacture of fine coatings, dress goods, etc. The

method of arranging the fibers in the formation of a woolen yarn is

such as to produce a strand with a somewhat indefinite and fibrous

surface, which destroys to a large degree the clearness of the pattern

effect in the woven piece. In the construction of worsted yarn the

fibers are arranged in a parallel relationship to each other,

resulting in the production of a smooth, hard yarn having a

well-defined surface; hence weave-ornamentation of a decided or marked

type is possible by its use. There is, in a word, more scope for

pattern effects, since the level and regular structure of the yarn

imparts a distinction to every part of a woven design. From this

peculiarity arises the great variety of effects seen in the worsted

dress fabrics, coatings, trouserings, etc., both in colored patterns

and in fabrics of one shade throughout.



Worsted yarn can be made of pure wool; and as a rule, the wool used in

the English system is of fairly good length and uniform staple, for if

otherwise it is only with difficulty that the yarn can be spun

straight. Shorter wool can be combed and spun under the French

system, and this is the reason why the French system of spinning is

being introduced. On the other hand, in the spinning of woolen yarns

great length of staple is not essential, for the machinery employed

will work the small fibers.



=Uses of Worsted Yarn.= Worsted yarn may be used in any of the

following fabrics:



1. Combed wool yarn for ornamental needlework and knitting, as Berlin,

Zephyr, and Saxony wools.



2. Cloth made from combed wool not classified according to material.



a. Fabrics of all wool--serge, bunting, rep, dress

goods, with weave effects.



b. Wool and Cotton--union goods, serge linings,

lathing.



c. Wool and Silk--rich poplin, pongee, henrietta,

bombazine.



d. Alpaca and Mohair--alpaca, mohair dress goods,

lusters, braids, laces.



=Counts.= Yarn is measured by a system of "counts"--the number of

yards of yarn to the pound. The counts of worsted yarn are based on

the number of hanks in one pound, each hank containing 560 yards. Thus

No. 30 worsted yarn consists of 30 hanks of 560 yards each, or 16,800

yards to the pound.





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