3. YARN COUNT
Count is an numerical
expression which denotes
the fineness or coarseness
the yarn or fibre.
According to the definition
of textile institute of UK
count means “weight per
unit length”or length per
unit weight of yarn.
There are two
system of yarn
count
1. Direct system
2. Indirect system
4. DIRECT SYSTEM
According to this system, yarn length is fixed and weight is variable.
However the following general formula can used to find count in all direct
system.
W X l
N = ——————–
L X w
Where,
N = The yarn in direct system.
W = The weight of the sample.
w=The weight units of yarn
L = The length of the sample.
l = The units of length of the system
5.
6. INDIRECT SYSTEM
According to this system, weight is fixed yarn and length is
variable.
However the following general formula can used to find count in
all indirect system.
L X w
N = ——————–
l X W
Where,
N = The yarn count in indirect system.
W = The weight of the sample.
w = The units of weight of the system
L = The length of the sample.
l = The units of length of the system
9. METHODS OF BEESLEY
BALANCE:
1. This instrument consists of a simple beam is initially
leveled to bring the poiter opposite adatum line.
2. A standrd weight is hung in a notch on the beam arm
on the pointer side of the pivot.
3. A template is used to cut short length of yarn,the
length depending upon the count system required.
4. These short lengths are added to the hook until the
pointer is opposite the datum line.
5. the count is the number of the short lengths required
to balance the beam.
6. When used in the analysis of small samples of fabric,a
rough estimate of the crimp should be made and the
count corrected.
10. YARN TWIST
Yarn twist means no of spiral
turns per unit length of yarns
the main function of twist is to
increase strength of the yarn up
to a certain point.
11. TYPES OF TWIST
Real twist::
To insert a real twist into a length of yarn, one end of
the yarn should be rotated relative to the other end,Spun
yarns usually have real twist, which holds the fibres
together in the yarn. as indicated in figure (a)
False twist:
When inserting false twist into a length of yarn, both
ends of the yarn are clamped, usually by rollers, and
twist is inserted with a false twister between the
clamping points, as indicated in figure (b)
14. S twist
When a twisted yarn is held vertically, the individual
filaments are appearing in this case as the diagonal in
the letter "S". The same can apply if several yarns have
been twisted together: their combined twist can again
appear as the diagonal of the letter "S".
Fig: Direction of S twist
TWIST
DIRECTION
15. TWIST DIRECTION
Z twist
When a twisted yarn is held vertically, the individual
filaments are appearing in this case as the diagonal in
the letter "Z". The same can apply if several yarns have
been twisted together: their combined twist can again
appear as the diagonal of the letter "Z".
Fig: Direction of Z twist