yarn formation test 1- yarn classification and numbering systems

first spun fibers in history

wool, flax

some of the first spinning technology

drop spindle, spindle wheel

advantages of spinning Jenny

several spindles, more efficient

product of substantial length and relatively small cross-section composed of staple fibers and/or continuous filaments

yarn

yarn classification

staple spun or continuous filament

has to be spun to form yarn

staple spun yarn

filament length=yarn length

continuous filament

staple yarn classification

short or long staple

short staple yarn is either

conventionally ring spun, or new

conventionally ring spun is either

combed or carded

new is either

airjet or open end

long staples are either

woolen or worsted

filaments are either

flat or textured

yarn classifications

single yarns or ply yarns

2 or more kinds of fibers

blended yarns

yarns are blended to…

obtain desired attributes

benefits of natural fibers

moisture absorbent, soft and warm, less static

benefits of synthetic fibers

strong, resist abrasion, wrinkles/creases, and chemicals

thermoplastic fibers improve…

crease retention

property of polyester

resilience

properties of nylon

tensile strength, abrasion resistance

property of wool

warmth

property of glass

high thermal resistance

property of cotton or wood pulp

moisture absorption

properties of rayon

softness and absorption

property of acrylic

chemical resistance

property of polypropylene

hydrophobic

common fiber blends

cotton/polyester, polyester/wool, nylon/cotton

cotton/polyester used for

t-shirts, bedding, terrycloth

used for suiting, coats

polyester/wool

used for activewear, intimates

nylon/cotton

combination of 2+ yarns/fibers by twisting

core/sheath blending

the core is the ____ yarn

filament

the sheath is ____ ____

staple fibers

core/sheath blending provides…

color/texture effects and functionality

staple spun yarn

twisted strand made from limited length fibers

yarn twist is measured in

turns/unit

yarn twist provides coherence from _____ _____ ____ and gives yarn ____

inter-fiber-friction, strength

transverse pressure causes ____ force

tensile

as pull force _____, pressure ______ contact between fibers (increase/decrease)

increase, increase

true or false: as pull force increases, inter-fiber-friction decreases

false, the inter-fiber-friction increases

the more twist, the stronger/weaker the yarn:

stronger

twist level which yarn exhibits maximum strength

optimum twist

yarn-twist relationship depends on ____ _____

fiber qualities

yarns may be twisted beyond optimal twist to…

enhance fabric elasticity and elongation, provide surface texture

slanted left

z-twist

slanted right

s-twist

yarns are plied to…

increase strength and balanced yarn structure

plying happens when yarns are…

twisted in the opposite direction during plying

single yarns tend to untwist which causes them to be ______

unbalanced

yarn composed of 1+ filament that run the whole length of the yarn

continuous filament yarn

infinitely long lengths

filaments

ribbon (tape), twisted, interlaced

non-textured (flat) filaments

false twisted, stuffer box crimped, bi-component, air jet

textured filaments

the natural curl/convolution in cotton and wool fibers provides…

yarn bulkiness which makes them comfortable in end use

yarn numbering systems

direct or indirect

direct systems (weight/unit length)

tex, dtex, denier

indirect system (length/unit weight)

cotton, metric, worsted

why the need for yarn numbering systems rather than yarn thickness?

unlike metal, yarns aren’t uniform and compressible and therefore thickness cannot represent the yarn

tex is defined as:

the weight in g of 1000 m

denier is defined as:

the weight in g of 9000 m

decitex is defined as:

the weight in g of 10,000 m

cotton count is defined as:

the number of cotton hanks per lb

cotton hank length

840 yards

worsted count is defined as:

the number of worsted hanks per lb

worsted hank length

560 yards

metric count is defined as:

the length in m per g

yarn number/count can be expressed in terms of:

yarn length, yarn weight

direct system numbering formula- tex

N(g/km)=W(g)*1000m/L(m)

direct system numbering formula- dtex

N(g/10km)=W(g)*10,000/L

direct system numbering formula- denier

N(g/9km)=W(g)*9000/L

indirect system numbering formula- cotton count

N(h/lb)=L/W(lb)*840h

indirect system numbering formula- worsted

N(h/lb)=L/W(lb)*560h

indirect system numbering formula- metric

N(m/g)=L(m)/W(g)

methods of determining yarn number:

skein method (used in preproduction), short yarn length method (used when short sample is available)

Ply yarn formula- direct

Nply=N1+N2+N3…

Ply yarn formula- indirect

1/Nply=1/N1+1/N2+1/N3…

why is 24/1 cotton count?

the bigger number is first

what would 24/1 indicate? and what system is it?

cotton count, 24 cotton hanks/lb, yarn is made of 1 strand

what would 50/2 indicate? and what system is it?

Cotton count, 2 ply yarn formed by plying two 50/1 strands. the resultant yarn cc is 25 cc

why is 1/25 worsted count?

smaller number is first

what would 1/25 indicate and system?

worsted, 25 hanks/lb, yarn is made of 1 strand

what would 2/64 indicate and system?

worsted, 2 ply yarn formed by plying two 1/64 strands, resultant yarn count is 32 wc

why is 40/1 Nm metric count system?

because of the Nm

what would 40/1 Nm indicate and system?

metric, 40 m/g and the yarn is made of 1 strand

what would 60/2 Nm indicate and system?

2 ply yarn formed by plying two 60/1 strands, resultant yarn count is 30 Nm

why is 1×20 tex count

its being multiplied, tex label

what would 1×20 indicate and system?

tex, 1000 m of yarn weigh 20g and the yarn is made of 1 strand

what would 2×20 indicate and system?

tex, 2 ply yarn formed by plying two 1×20 strands, resultant tex is 40 tex

what would 1×70 den indicate and system?

denier, 9000m of yarn weigh 70g and the yarn in made of a single strand

what would 2×150 den indicate and system?

denier, 2 ply yarn formed by plying two 1×150 den strands, resultant den count is 300 den

what would 1×200 dtex indicate and system?

decitex, 10,000m of yarn weigh 200g and the yarn is made of a single strand

what would 2×200 dtex indicate and system?

decitex, 2 ply yarn formed by plying two 1×200 dtex strands, resultant dtex is 400