Spinning Calculation

CONSTANTS AND CALCULATIONS

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.

INDIRECT 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

DIRECT 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 

      SPINNING CALCULATION

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