In manufacturing worsted yarn every necessary operation is performed
to arrange the wool fibers so that they will lie smoothly and parallel
to each other. In the case of woolen yarn every operation is performed
so as to have the fibers lie in every direction and to cross and
overlap each other.
To produce yarn of the woolen type a set of machinery entirely
different from that used in worsted manufacture is necessary. The wool
is carded, but no attempt is made to get the fibers parallel. The
reduction in thickness of the sliver is not brought about upon the
so-called drawing frame, but by a mule frame where the drawing and
twisting are done at the same operation. As neither combs nor gills
are employed, there is not the same smooth, level yarn, but one which
possesses a fringe-like covering or fuzzy appearance that makes the
woolen yarn so valuable.
The operation is as follows:
=Carding.= After washing the material for woolen yarn, it is passed
through three carding processes, and from the last of them is taken
direct to the spinning frame to be made into yarn. The object of
woolen carding is different from carding in any other textile
In most processes of carding the fibers are subjected to a "combing"
principle, and the aim is to lay the fibers parallel. Woolen carding
aims to open the raw wool fiber, and put it in a perfectly loose
condition, without leaning toward any definite arrangement.
The carding machines are called, respectively, first, second, and
third breaker. Each machine consists of a complicated series of
card-covered cylinders of different sizes, running at different rates
of speed--sometimes in the same and sometimes in an opposite
direction. These rollers take the wool from one another in regular
order until it is finally delivered from the third breaker in a soft,
fluffy rope or roll called a sliver. This sliver is wound on a bobbin,
and taken from the card to the mule spinning frame.
The sliver on the bobbins from the card is taken to the mule spinning
frame where it is passed through rolls, and the sliver attenuated by
means of a traveling carriage.
=Count.= In the case of woolen yarn there are numerous systems for
denoting the count, varying with the locality in which it is spun and
the character of the product. In the United States there are two
systems employed, but the one in most general use is known as
"American run counts." This is based on the number of "runs," each
containing 1,600 yards to the pound. Thus, a yarn running 8,000 yards
to the pound is called a 5 "run" yarn, a yarn with 5,200 yards to the
pound is equal to a 3-1/4 "run."
In the vicinity of Philadelphia woolen yarn is based on the "cut,"
each cut consisting of 300 yards, and the count is the number of cuts
in a pound. Thus, No. 30 cut yarn consists of 9,000 yards to the
pound. No. 15 contains 4,500 yards to the pound.
Woolen yarn is suitable for cloths in which the colorings are blended
and the fibers napped, as exemplified in tweed, cheviot, doeskin,
broadcloth, beaver, frieze, chinchilla, blanket, and flannel.
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