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1 Fiber Formulas Commonly used fibre formulas and reference guides used by the textile fibre industry. Fiber Formulae Name Description Micronaire value of cotton (Micrograms per inch) Average weight of 1 inch of fibre in Micrograms (1/1000,000 gms) Denier (for man-made fibres) Weight in gms per 9000 metres of fibre Micron (micro-metre) (μm) (fibre diameter) (normally for Wool) 0.001 mm Denier 0.354 x Micronaire value Micronaire Value 2.824 x Denier Fibre diameter ( μ ) 11.3 x √ ( dtex / sp.gr) = 11.9 x √ (den / sp.gr) Tenacity values: Kg / mm2 9 x (g/den) x Sp.gr. = RKM value x Sp.gr. = (g/tex) x Sp.gr. Tenacity Conversion Tenacity Conversions (Free Strength) g = gms Textile calculations Page 1

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Fiber Formulas

Commonly used fibre formulas and reference guides used by the textile fibre industry.

Fiber Formulae

Name Description

Micronaire value of cotton (Micrograms per

inch)

Average weight of 1 inch of fibre in

Micrograms (1/1000,000 gms)

Denier (for man-made fibres) Weight in gms per 9000 metres of fibre

Micron  (micro-metre)  (μm) (fibre diameter)

(normally for Wool)0.001 mm

Denier 0.354  x Micronaire value

Micronaire Value 2.824 x Denier

Fibre diameter ( μ )  11.3 x √ ( dtex / sp.gr) =  11.9 x √ (den / sp.gr)

Tenacity values: Kg / mm29 x (g/den) x Sp.gr. = RKM value x Sp.gr. =

(g/tex) x Sp.gr.

 Tenacity Conversion

Tenacity Conversions (Free Strength) g = gms

  g/den g/tex g/dtex cN/tex

g/den 1 ( g/tex ) / 9 ( g/dtex ) x 10 / 9 ( cN/tex ) x 0.113

g/tex ( g/den ) x 9 1 ( g/dtex ) x 10 ( cN/tex ) x 1.02

g/dtex ( g/den ) x 0.9 ( g/tex ) / 10 1 ( cN/tex ) x 0.102

cN/tex ( g/den ) / 0.113 ( g/tex ) / 1.02 ( g/dtex ) / 0.102 1

Spinning Formulas

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Formulas used for yarn spinning production including various yarn numbering system

conversions

Common Formulas

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)/1.605grams per meter = 0.5905/Ne

  

Drawframe

Break draft surface speed of 2nd roller / surface speed of back roller

Main draft surface speed of 1st roller / surface speed of 2nd( middle) roller

Total draft surface speed of delivery roller / surface of feed roller

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

Production 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

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Ne - Sliver hank

Nd - number of deliveries

Winding

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

Production in kgs / hr

( L x 1.0936 x 60 x effy ) / (hank (Ne) x 36 x 840 x 2.2045)

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

Carding

Production in kgs / hr

( L x 1.0936 x 60 x effy ) / (hank (Ne) x 36 x 840 x 2.2045)

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

Production in kgs / hr (L x Ktex x 60 x effy) / ( 1000 )

L - delivery speed in m/min

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Ktex- sliver count in Ktex (kilotex)

effy - efficiency

1000- to convert to kilograms from grams

Production in kgs / 8 hrs

(0.2836 x L x effy) / (Ne)

L - delivery speed in m/min

effy - efficiency

Ne - English count

Production / 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

Total draft in card (feed weight in g/m) / (sliver weight in g/m)

  

Speedframe & Ringframe

Twist / Inch (TPI)

Spindle speed / FRS

FRS - front roller surface speed in inches/mi

FRS = FRrpm x 3.14 x FRD

FRS - Front roller surface speed

FRD - front roller diamete

T.P.I

T.M. x sqrt(count or hank)

T.M. - Twist multiplier

sqrt - square root

Production in kgs / 8 hrs

(7.2 x SS x effy) / (TPI x Ne x 1000)

SS - spindle speed

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Spindle speed m/min x TPI x 39.37

Hank delivered spindle speed / ( tpi x 62.89)

Ring traveller speed in m/sec (spindle speed x ring dia in mm x 3.14) / (60 x 1000)

Yarn Conversions

Various yarn numbering systems and conversion formulas and tables for easy reference

English/Metric Conversion Table: Length

  Inch Yard Centimeter Meter

Inch   0.278 2.54 0.0254

Yard 36   91.44 0.9144

Centimeter 0.3937 0.011   0.01

Meter 39.37 1.094 100  

  

English/Metric Conversion Table: Mass/Force

  Ounce Pound Gram Centi-Newton Newton

Ounce   0.06237 28.3495 27.783 0.27802

Pound 15.96772   453.6 444.528 4.44528

Gram 0.0353 0.0022   0.98 0.0098

Centi-Newton 0.035904 0.002248 1.02   0.01

Newton 3.5904 0.2248 102 100  

  

English/Metric Conversion Table: Saturated Steam Gauge

Pressures

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  Pascal Kilo-Pascal Pounds per square inch

Pascal(Pa)   0.001 1.45

Kilo-Pascal(kPa) 1000   0.145

Pounds per square inch(Psi) 6895 6.895  

  

English/Metric Conversion Table: Tenacity

  gf/den gf/tex cN/tex Rkm

gf/den   9.015 8.838 9.015

gf/tex 0.111   0.9807 1

cN/tex 0.113 1.02   1.02

Rkm 0.111 1 0.9807  

Count Conversion Table

tex dtex den Nm NeC NeL

tex   dtex/10 den/9 1000/Nm 590.54/NeC 1653.5/NeL

dtex tex*10   den/0.9 10000/Nm 5905.4/NeC 16535/NeL

den tex*9 dtex*0.9   9000/Nm 5314.9/NeC 14882/NeL

Nm 1000/tex 10000/dtex 9000/den   NeC*1.6934 NeL*0.6048

NeC 590.54/tex 5905.4/dtex 5314.9/den Nm*0.5905   NeL/2.8

NeL 1653.5/tex 16535/dtex 14882/den Nm*1.6535 NeC*2.8  

Count Conversion Calculator

Size (convert from):

Unit (convert from):

Decimal Places:

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System Symbol Value Remarks

Direct Systems

tex Tt 0 grams/kilometer

deciTex dtex 0 grams/10 kilometer

kiloTex ktex 0 kilogram/kilometer

denier Td 0 grams/9'000 meters

Linen (dry spun), Hemp, Jute Tj 0 lb/14,400 yd (spindle)

Woollen (Aberdeen) Ta 0 lb/14400 yd

Woollen (US grain) 0 grains/20 yd

Indirect Systems

Asbestos (American) NaA 0 100 yd (cut)/lb

Asbestos (English) NeA 0 50 yd/lb

Cotton (Bump Yarn) NB 0 yd/oz

Cotton (English) NeC 0 840 yd (hank)/lb

Glass (UK & USA) NG 0 100 yd/lb

Linen (Wet or Dry Spun) NeL 0 300 yd (lea)/lb

Metric Nm 0 kilometers/kg

Spun silk Ns 0 840 yd/lb

Typp Nt 0 1000 yd/lb

Woollen (Alloa) Nal 0 11'520 yd (spindle)/24 lb

Woollen (American Cut) Nac 0 300 yd/lb

Woollen (Americal run) Nar 0 100 yd/oz

Woollen (Dewsbury) Nd 0 yd/oz

Woollen (Galashiels) Ng 0 300 yd (cut) 24 oz

Woollen (Hawick) Nh 0 300 yd (cut)/26 oz

Woollen (Irish) Niw 0 yd/0.25 oz

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System Symbol Value Remarks

Woollen (West of England) Nwe 0 320 yd (snap)/lb

Woollen (Yorkshire) Ny 0 256 yd (skein)/lb

Woollen (Yorkshire) Ny 0 yd/drum

Worsted New 0 560 yd (hank)/lb

lb = pund(s), yd = yard(s), oz = ounce(s), kg = kilogram(s

Weaving Formulas

Commonly used weaving formulas and reference guides used for manufacturing woven fabrics

Count

A number indicating the Mass per unit Length OR

The length per unit mass of Yarn.

Expression of the fineness of Yarn.

There are three Systems to Calculate Count

1 Lea = 120 yd

7 Leas = 1 hank

1 Hank = 840 yds. or 768 meter

1. Indirect System

2. Direct System

3. Universal System

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1. Indirect system

Total No. of hanks per one pound is the count of that yarn (Ne) i.e. if 10 hanks (10 x 840 yds. or

7680 meters) weighs one Pound or 0.454 Kg, then the Count of Yarn in indirect system 10s or

10Ne.

This System widely used for staple fiber spun yarns like 100% Cotton, Viscose, Polyester fibers

and their blends.

Higher the yarn Count i.e Ne the yarn is finer

Count = Length in hanks(840 yards)/Weight in Pounds

2. Direct System

Count = Weight in grams per 9000 meters of yarn

In this system the yarn numbering is called as Denier (D)

Higher the yarn number i.e Denier the yarn is coarser.

3. Universal System

Count = No of grams per 1000 meters or per km of yarn.

In this system count is called as Tex

Weight in Pounds

Length in hanks (840 yards)

Count = Commonly used other numbering systems

1. Nf - French count: - It is the No of 1000 meters length in ½ kg of yarn

2. Nm - Metric system: - Count is the No of 1000 meters length per kg. of yarn.

3. Worsted system: - Count is the No. of 560 yards in one lbs.

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4. Linen system: - It is the No. of leas of 300 yards per pound

5. Hemp, Jute, Flax: - Count is the No of 14,400 yards length per pound of yarn

Conversion System

English (Ne) to Denier (D) - Denier = 5315 / Ne

English (Ne) to Tex - Tex = 590.5 / Ne

French (Nf) to English (Ne) - English (Ne) = Nf x 1.181

Twist per Inch or meter (TPI or TPM)

To give strength to the yarn, certain twist is given in the yarn.

TPI vary according to end use of yarn. More twist for warp yarns, medium twist for weft

yarns and less twist for hosiery yarns.

We calculate the twist as TPI or TPM.

Twist is given in ‘Z’ direction or ‘S’ direction.

If twist is given in CW direction it is ‘Z’ twist.

If it is given in CCW direction it is ‘S’ twist.

Single yarns are given ‘Z’ twist and double yarns are given ‘S’ twist.

Twist relation for double yarn TPI = 0.7 x Single yarn TPI

Conversions Factor

This page helps in determining the Various convertion factors whether it is for textile use or for

common use.

Conversion factor for Textile Use

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To Convert From To Multiply by

Threads in Fabric:

Number per inchNumber per centimetre 0.3937

Stitches in Fabric:

Number per inchNumber per centimetre 0.3937

Mass per unit area:

Ounce per sq. yard

Gram per sq. metre

Momme

Gram per sq. metre

Momme

Ounce per sq. yard

33.906

0.23

0.128

Twist Level

Turns per inchTurns per metre 39.37

Dimetre

1/1000 inch

inch

inch

Micrometre

millimetre

centimetre

25.4

25.4

25.4

Cover Factor

a. Woven cotton fabrics

b.Weft knitted worsted fabric

0.957 

1.172

Twist factor (or multiplier)

9.57

Gram force

Pound Force

Kilogram Force

Millinewton

Newton

Decanewton

9.81

4.45

0.98

Tearing Strength Newton 4.45

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To Convert From To Multiply by

Pound Force

Tenacity

Gram force per denierMillinewton per Tex 88.3

Bursting Pressure

Pound force per sq.inchKilonewtons per square metre 6.89

Conversion factor for Textile Use

To Convert From To Multiply by

Threads in Fabric:

Number per inchNumber per centimetre 0.3937

Stitches in Fabric:

Number per inchNumber per centimetre 0.3937

Mass per unit area:

Ounce per sq. yard

Gram per sq. metre

Momme

Gram per sq. metre

Momme

Ounce per sq. yard

33.906

0.23

0.128

Twist Level

Turns per inchTurns per metre 39.37

Dimetre

1/1000 inch

inch

inch

Micrometre

millimetre

centimetre

25.4

25.4

25.4

Cover Factor

a. Woven cotton fabrics

b.Weft knitted worsted fabric

0.957 

1.172

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To Convert From To Multiply by

Twist factor (or multiplier)

9.57

Gram force

Pound Force

Kilogram Force

Millinewton

Newton

Decanewton

9.81

4.45

0.98

Tearing Strength

Pound ForceNewton 4.45

Tenacity

Gram force per denierMillinewton per Tex 88.3

Bursting Pressure

Pound force per sq.inchKilonewtons per square metre 6.89

Weaving Calculations

A guide to calculations relating to yarn and cloth and all processes of weaving.It includes reed

count, reed width, Maximum EPI for particular count, weave density, crimp percentage, cloth

cover factor etc

Some important Weaving Calculations

1. Reed Count

It is calculated in stock port system.No. of dents in 2 inches is called Reed Count.

Reed Count = EPI/(1 + Weft crimp %age)

2. Reed Width

Reed Width = Cloth Width *(100+ weft crimp %age)/100

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3. Crimp Percentage

Crimp %age = {(Warp length - Cloth length)/Cloth Length}* 100

Crimp %age = {(Warp width - Cloth width)/Cloth width}* 100

4. Cloth Cover Factor

1.

2.

3. Cloth Cover Factor = Wp.C.F +Wt.C.F. - {(Wp.C.F. - Wt.C.F)/28}

5. Maximum EPI for particular count

1.

2.

 

3.

4. other design = (Ends /Repeat * 1/Yarn Diametre)/ (No of

intersections/repeat+ ends/repeat)

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5.

6. Warp Density

o

o

                            = <350

o Weave Density = 50+{(Warp Density - 100) * F.D - 100} /{(Weft Density -

100)* F.D - 100}

o Effective Weave Density = W. D x K of loom width x K of Design

                                     = < 72

Wp / filling - K  Loom Width - K  Weave Design - K

Cotton = 1.00 140 cm - 0.99 Plain1/1 = 1.00

Polyester/Cotton = 1.03 180 cm - 1.00 Twill 1/2 = 0.87

Viscose Filament = 1.17 190 cm - 1.01 Matt, Gabardine 2/2 = 0.82

Polyester Filament = 1.22 220 cm - 1.02 Drill 1/3 = 0.77

250 cm - 1.08 Satin 1/4 = 0.69

330 cm - 1.15

360 cm – 1.20

To change the count and the number of thread / inch , keeping the same denseness

of fabric

To change the count without altering the denseness of the fabric

EPI in Exp.cloth = (EPI in exp.Cloth2/EPI in given cloth) * count in given cloth

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To change the EPI without altering the denseness of the fabric

Warp requirement to weave the cloth

o Warp weight in grams /metre = {(Total Ends * 1.0936 * 453.59 * crimp %)/(840

* count)} * wastage %

o Weft weight in grams /metre ={(R.S. in inches * 453.59 * PPI)/(840 * count)} *

wastage % * crimp %

o Cloth length in metres with given weft weight=( weft weight in kgs * weft count *

1848 * 0.9144)/(PPI * R.S in inches)

For silk and Polyester

o Warp weight in grams /metre ={(Total Ends * count (Denier) )/9000} * wastage

% * crimp %

o Weft weight in grams /metre = {(R.S in inches * count(Denier)* PPI)/9000}*

wastage % * crimp %

Allowance for count in bleached and Dyed fabric

1.Count becomes 4%

2. FinerDyed counts become max 6% Coarser

Fabric Production Calculation

o Loom Speed = Motor RPM * (Motor Pully Diametre)/(Loom Pully Diametre)

o Loom Effeciency Percentage = (Actual Production/Calculated Production )* 100

o Moisture Regain Percentage = {(Yarn Weight - Dried Yarn Weight)/Dried Yarn

weight} * 100

o Moistue Content Percentage = {(Yarn Weight - Dried Yarn Weight)/Yarn

weight} * 100 

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Type of Yarn Moisture Regain % Moisture Content %

Cotton 8.50 7.83

Jute 13.75 12.10

Silk 11.00 9.91

Rayon, Viscose 11.00 9.91

Wool 17.00 14.50

Nylon 4.20 3.78

o Warp Weight in Kg = (Total Ends * Tape Length in metres)/(1693.6 * Warp

Count)

o Weft Weight in Kg = (R.S in centimetres * cloth length in metres * PPI

)/(4301.14 * weft Count)

o Cloth weight in GSM = {EPI/Warp Cout)+(PPI/Weft count)}* 25.6

o oz (ounce ) per sq. yard = GSM(Grams per sq. metre)/34

Material Measurement 

 To calculate the length of any rolled fabrics, this formula gives the nearest accuracy.

  L = {0.0655(D-d)(D+d)}/t 

 Where L = Length of material (Feet)    t = Thickness of fabrics (inches) 

           D = Outside diameter (inches)   d = Inside diameter (inches)

Weight of yarn in a cloth

The weight of cloth manufactured on looms depends upon the weight of yarns in thewarp

and weft: ends/inch, picks/inch and the weight of size on the warp. Therefore,

 Cloth weight = Weight of warp + Weight of weft + Weight of size (All inlbs.)

Where as Weight of warp in lbs. = (Total No. of Ends * Tape Length in Yards)/(840 *

warp yarn count)

Also 

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 FIBRE Top

          Micronaire value (cotton) - 

          Micrograms/ inch. The average weight of one inch length of fiber, expressed in

micrograms (0.000001g), which is approximately equivalent to, Micronaire Readings defined by

A.S.T.M

          Denier(Man-made fiber)

          Weight in grams per 9000 meters of fiber

          Micron(wool)

          Fineness expressed as fiber diameter in microns             (0.001mm).

           Conversions

           Denier = 0.354 * micronaire value

           Micronaire value = 2.824 * Denier

           HVI

           SF = 50.01 - (0.766 * 2.5%SL) - (50%SL *81.48) 

         Where SL is in inches

       

 YARN COUNTS

           (A) Indirect system

               English count (Ne)

              Number of 840 yards per pound.

              French count (Nf)

              Number of 1000 meters per kilogram.

              worsted count

             Number of 560 yards per pound.

              Woolen cut Scllnen Lea (wet spun)

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              Number of 300 yards per pound.

            (B) Direct System

               Tex count

               Weight in grams per 1000 meters

              Weight in pounds per 14,400 yards (Spyndle)

                Denier

              Weight in grams per 9000 metres

COUNT CONVERSION Top

       Calculator

        1. English count=

             French count * 1.1810

             Metric count *  0.5905

             Worsted count * 0.6667

             Wollen  cut 8c Linen Lea * 0.3571

             5905 * Tex count

             5315 * Denier

             17.14 * jute count

        2. Metric count=

             English count * 1.693

             French Count * 2.0

             Worsted count * 1.129

             Woolen cut 8c linen lea * 0.6047

             1000 * Tex count

             9000 * Denier

             29.03 * Jute count

        4. Tex count

            590.5 * English count

            500 * French count

            1000 * Metric count

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            885.8 * worsted count

            1654 * Wolen cut and linen lea

            0.1111 * denier

            34.45 * jute count

          5. Denier

            5315 * English count

            4500 * French count

            9000 * Metric count

            7972 * worsted count

            14880 * woolen cut and linen lea

            9 * tex

            310 * jute count

UNITS CONVERSATION  Top

Calculator

One Pound    = 16.00 ounces One Kilogram =1000.0 grams

                     = 7000 grains =2.2046 pound

                     = 453.59 grains =35.274 ounces

                     = 0.4536 kilogram =15432.0 grains

One Ounce    =    437.50 grains One gram =1000.0 milligram

                     = 28.350 grains =0.03527 ounces

=15.432 grains

One grain     = 0.00229 One Milligram =0.0154 grain

                      = 0.0648 gram

                      = 64.8 milligram

LINEAR

MEASURES

Calculator

One yard      = 3.0 feet One meter = 100.0 centimeter

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                   = 36.0 inches = 3.281 feet

                   =  91.44 centimeters = 39.37 inches

                   = 0.9144 metre =1.0936 yards

One Foot      =  0.3333 yards One millimeter =0.0334 inches

                   = 12.0 inches One inch =0.0278 yard

                   = 30.48 centimeters =0.0833 foot

                   = 0.3048 meter =25.4 milimeters

=2.54 centimeters

=0.0254 meter.

TEMPERATURE AND HUMIDITY IN

COTTON TEXTILE MILLS Top

Department Relative Humidity % Temperature  C (F)

Min. Max. Min. Max

Mixing  Room 60 65 27 (80) 33 (92)

Blow Room 50 55 27 (80) 35 (95)

Card Frame 50 55 27 (80) 35 (95)

Ring Frame 53 58 30 (80) 35 (95)

Winding 60 65 27 (80) 33 (92)

Top  

  MIXING

BLOWROOM Top  

1.        Cleaning efficiency percentage: (CE%)

           (Trash in mixing - Trash in Lap * 100) / Trash in mixing

2.         Beating / inch  

(Beater rpm * no. of arms) / (Feed roller rpm * (22/7) *  Feed roll diameter in inch)

EXAMPLE:

(Beater speed = 800; Arms = 3; Feed roller rpm = 10; Feed roller diameter =2.5"

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Beats / inch = (800 * 30) / (10 * 3.14 * 2.5 ") = 30 Approx.

3.           Standard pressure when spinning cotton and synthetic.

Synthetic Cotton

On rack heads 300 Kg / cm2 300 Kg/cm2

On Calendar Roller 3000Kg / cm2 2700 Kg /cm2

Pulling Device 130Kg / cm2 130 Kg / cm2

4.         Expected standard efficiency %

            For Auto Doffing is 88 to 90%  (Allowing for mixing change and cleaning)

5.        Lap Tolerance Limits = (Avg. Lap Wt. + - (2 * C.V %* Nominal Wt.))/ 100

Coefficient of variation of lap Norms

One yard Good Avg.

Full Lap 0.70 1.0

Wrapping 1.2 2.0

6. Norms of wrapping C.V 

Satisfactory values of % C.V. for wrapping in Preparatory & spinning

Wrapping Length in m %C.V U%

Blow room lap 1 1

Card silver 10 2.0 3.5

Finisher Drawing

Sliver 1 0.85 2.2

Inter  5 1.5 3.3

Yarn up to 60 Ne 100 1.2

Yarn 60 Ne and above 100 1.5

Yarn up to 60 Ne

(Strength CV) 3

Yarn 60 Ne and above

(Strength CV) 4.5

CARDING   Top

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1. Cleaning Efficiency (%)

 (( Trash in Lap - Trash in Silver) / Trash in Lap)*100

2. Twist inserted / inch in sliver

 (rpm of can plate ) / Surface speed of calendar Roller

 

DRAW FRAME

1. Roller setting for 3 Roller Drawing

 Front Zone = AFIS 5% Length Back zone = AFIS 5% + 4m.m.

2. C.V of  Sliver = C/ Sqrt N

C =C.V of creel sliver ; N = Number of slivers fed

 

SPEED FRAME

1 Coils per inch

For Coarse Roving = T.P I * 10 

For fine Roving =T.P I * 13 

2 Thumb Rule for Layers / cm. =5.12 / sqrt (Roving hank)

YARN

1. Natural variation = CV % * 2

   Let CV = 1.2 ; count = 30 

   (1.2 * 2 * 30 ) / 100 = 0.72

   30 +- 0.72 Ne

2. Ring Yarns

     Single yarn strength in gram * 0.264 = lea strength of 120 yards in Lbs.

    Rotor Yarns

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     (i) Cotton RKM = 0.00525 * CSP + 0.842

     (ii) Cotton Blended RKM = 0.00537 * CSP + 0.943

     (iii) Man Made RKM = 0.00561 * CSP + 1.079

 

3. Coils / inch (yarn gap should be equal to half the diameter of yarn between      consecutive

coils) By Thumb Rule = 13.3  * sqrt (count)

4 General formula for tape Width

Tape width = Face width of spindle Wharve - 4mm

WINDING Top

1. Yarn quality Factor = Clearing Efficiency / Knot factor

2. Pre clearer Gauge at winding (carded yarn) 4.0 * yarn diameter

Pre clearer Gauge at winding (combed yarn) 5 * yarn diameter

3. Clearing Efficiency=

100 * (Total unwanted Faults Removed by Clearer) / ( Total Number of such faults

Present in the yarn)

4. Knot Factor = ( Total number of Clearer cuts) / (Number of unwanted yarn faults

removed)

5. Normal Clearing Efficiency and knot Factor

Type of Clearer CE Knot Factor     

Electronic Clearer  80-95 < 1.3     

6. Yarn Tension level

               (1 / 20) * single yarn Strength

DOUBLING

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1. Total imperfection in Double yarn=0.170 * Total

imperfection in single yarn

2. Doubling yarn strength = Ring yarn strength * 2.5

3. Double yarn U% = Single yarn U% / sqrt ( No of yarns)

4. Doubling Tension weight in gram  = ( Lea strength in Lb

* 4) /15.4

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