Textile constants and calculations - important


FIBRE FINENESS, YARN COUNTS AND CONVERSIONS:
Micronaire value(cotton) :
The unit is micrograms per inch.  The average weight of one inch length of fibre, expressed in micrograms(0.000001 gram).
Denier(man-made fibres): Weight in grams per 9000 meters of fibre.
Micron:(wool): Fineness is expressed as fibre diameter in microns(0.001mm)
Conversions:
·         Denier = 0.354 x Micronaire value
·         Micronaire value = 2.824 x Denier  
YARN COUNTS:
It is broadly classified into 1. DIRECT and 2.INDIRECT system.
DIRECT SYSTEM:
·         English count (Ne)
·         French count(Nf)
·         Metric count(Nm)
·         Worsted count
·          
Metric system:  Metric count(Nm) indicates the number of 1 kilometer(1000 meter) lengths per Kg.
Nm =  length in Km / weight in kg  (or)
Nm = length meter / weight in grams

INDIRECT SYSTEM:
·         Tex count
·         Denier
CONVERSION TABLE FOR YARN COUNTS:
tex
Ne
den
Nm
grains/yd
tex


den/9
1000/Nm
gr.yd   x 70.86
Ne
590.54/tex

5314.9/den
Nm x .5905
8.33 / gr/yd
den
tex  x  9


9000/Nm
gr/yd  x 637.7
Nm
1000/tex

9000/den

14.1 / gr/yd
grains/yd
tex / 70.86

den / 637.7
14.1/Nm

Where, Nm - metric count, Nec - cottoncount


CONVERSION TABLE FOR WEIGHTS:
ounce
grains
grams
kilograms
pounds
ounce

437.5 grains
28.350 grams


grains
0.03527 ounces

0.0648 grams


grams
0.03527 grains
15.432 grains

0.001 kgs

kilograms
35.274 ounces
15432 grains
1000 grams

2.2046 pounds
pounds
16.0 ounces
7000 grains
453.59 grams
0.4536 kgs

CONVERSION  TABLE FOR LINEAR MEASURES:
yard
feet
inches
centimeter
meter
yard

3 feet
36 inches
91.44 cms
0.9144 meter
feet
0.3333 yards

12 inches
30.48 cms
0.3048 meter
inches
0.0278 yards
0.0833 feet

2.54 cms
0.254 meter
centimeter
0.0109 yards
0.0328 feet
0.3937 inches

0.01meter
meter
1.0936 yards
3.281 feet
39.37 inches
100 cms


CALCULATIONS:
·         grams per meter = 0.5905 / Ne
·         grams per yard = 0.54 / Ne
·         tex = den x .11 = 1000/Nm = Mic/25.4
·         Ne = Nm/1.693
·         DRAFT = (feed weight in g/m) / (delivery weight in g/m)
·         DRAFT = Tex (feed) / Tex(delivery)
·         DRAFT = delivery roll surface speed / feed roll surface speed
·         No of hanks delivered by m/c =   (Length delivered in m/min) / 1.605
·          
CARDING:
(1). P =( L x 1.0936 x 60 x effy ) / (hank (Ne) x 36 x 840 x 2.2045)
P - production in kgs / hr
L - delivery speed in m/min
effy- efficiency
Ne - English count ( number of 840 yards in one pound)
840 - constant
2.2045- to convert from lbs to kilograms
(2).production in kgs / hr = (L  x  Ktex   x 60  x   effy)  / ( 1000)
L - delivery speed in m/min
Ktex- sliver count in Ktex (kilotex)
effy - efficiency
1000- to convert to kilograms from grams
(3). production in kgs / 8 hrs = (0.2836  x L x effy) / (Ne)
L - delivery speed in m/min
effy - efficiency
Ne - English count
(4).prodn / 8 hrs = (Hank x Nd) /( Ne x 2.2045)
Hank = no of hank (840 yards)delivered by the machine
Nd = no of deliveries
Ne = hank of the material
(4).Total draft in card = (feed weight in g/m) / (sliver weight in g/m)
DRAWFRAME:
(1.)Break draft = surface speed of 2nd roller / surface speed of back roller
(2).Main draft = surface speed of 1st roller / surface speed of 2nd( middle) roller
(3).Total draft = surface speed of delivery  roller / surface of  feed roller
(4).production in kgs / 8 hrs = (0.2836  x L x effy x Nd) / (Ne)
L - delivery speed in m/min
effy - efficiency
Ne - english count
Nd - No of delvieries
(5.).prodn in kgs / hr  =   (FRD x FRrpm x 3.14 x 60 x effy  x Nd) / (Ne x 840 x 36 x 2.2045) 
FRD - front roller dia in inches
FRrpm - front roller rpm
effy - efficiency
Ne - Sliver hank
Nd - number of deliveries

SPEEDFRAME + RINGFRAME
(1).Twist / Inch (TPI) = Spindle speed / FRS
FRS - front roller surface speed in inches/min
(2).FRS = FRrpm x 3.14 x FRD
FRS - Front roller surface speed
FRD - front roller diameter
(3).T.P.I = T.M. x sqrt(count or hank)
T.M. - Twist multiplier
sqrt - square root
(4).prodn in kgs / 8 hrs = (7.2 x SS x effy) / (TPI x Ne x 1000)
SS - spindle speed
(5).Spindle speed = m/min x TPI x 39.37
(6).hank delivered   = spindle speed  / ( tpi x 62.89)
(7).Ring traveller speed in m/sec =( spindle speed x ring dia in mm x 3.14) / (60 x 1000)
WINDING:
(1). production in kgs / 8 hrs = (0.2836  x L x effy x Nd) / (Ne)
L - delivery speed in m/min
effy - efficiency
Ne - english count
Nd - No of delvieries
(2). P =( L x 1.0936 x 60 x effy ) / (hank (Ne) x 36 x 840 x 2.2045)
P - production in kgs / hr
L - delivery speed in m/min
effy- efficiency
Ne - English count ( number of 840 yards in one pound)
840 - constant
2.2045- to convert from lbs to kilograms

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