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Sitra Norms For Spin. SITRA NORMS FOR SPINNING MILLS

EXPANDED CONTENTS

I COTTON QUALITY

Span Length

Mean Length

Upper – Half Length

Micronaire and Maturity - ;

Fibre Strength

Sampling from Bales of Cotton

Fibre Properties

Quality of Indian Cotton

Fibre Quality Index - Defination

TM For Maximum Strength Fibre Yarn relationship Using HVI/FMT Measured Fibre Properties

Fibre Properties For Warp Yarns

Cottons Used For Warp Yarns

Norms For Hosiery Yarns

Fly Liberation During Knitting

Norms For Process Proficiency

Fibre Properties for Different Levels of Yarn U %

SITRA’ s Prediction Expression for Yarn Unevenness Using HVI/FMT measured Fibre Properties

Relative Contribution of Fibre Properties to Yarn CSP and U%.

Relationship between Fibre length & Measured by different Instrument.

Relationship between Fibre Strength & Measured by different Method.

HVI Test system

Trash in Cotton (%)

Nep Content of Some Indian cotton

Nep Content of Some important cotton - .

II BOWROOM : -

Trash IN Lap (%)

Cleaning Efficiency (%) & Lint in waste (%) in modern Blow Room Lines.

Blow Room waste (%)

Cleaning efficiency of individual beating Points.

Fibre Rupture & Nep Generation in Blow Room

C.V% of Blow Room Lap

Running in time of Bale opener with respect to scuther.

III CARDS : -

Trash content in Card Sliver (%).

Combined Cleaning Efficiency of Blow Rom & Cards (%)

Waste % in Cards.

Neps in card web Using shirley template

Neps in Card Sliver ( VHP Cards)

Card setting for cotton

Neps Removal Efficiency of Cards

Unevenness Of Card sliver.

IV COMBERS : -

Comber Preparatory

Combing Efficiency

Norms for Combing Efficiency

Nep Removal Efficiency of Combers.

Process parameter’s of Comber

Sliver Breaks & Roller Lapping.

Comber Sliver Unevenness (U%)

Reduction in Yarn Imperfection at Different

Level of Noil Extraction.

Sitra Norms For Spin.

V DRAWINNG : -

Draw Frame Sliver c.v%

Draw Frame Sliver Unevenness (U%) Finisher passage

Diameter of Trumpet Hole.

End break in Drawing

Recommended setting in Draw Frame Based AFIS length Data.

Break Draft in high Speed Draw Frame

VI FLY FRAME : -

Roving Unevenness

Roving variation c.v%

Ends break in Fly Frame

Variation in empty Roving Bobbin Diameter

Roller Setting in Fly Frame Based on 2.5% Span length

Size of Sliver Condensing Guides in Fly Frame

Size of Floating Condenser & Spacer in Fly Frame

Creel Tension Draft

Optimum level of pneumafil suction Pressure in Fly Frame.

Strech in Roving

VII YARN QUALITY : -

Yarn CSP for Warp Cunts

Yarn Unevenness (U%)

Yarn Imperfection / Km.

Yarn Classimat Fault / 100 Km

Count & Strength c.v%

Yarn Appearance Grade

Wraps per cm for Grading Yarns.

RKM Value

Fibre quality require to spin yarn with 3 different level of RKM under Good Working condition

(Fibre properties measured by HVI test system using ICC mode. ( Coarser Fibres.)

Yarn Hainess values ( Hair/mtr. With hair length 33 mm & above)

Number of test & Precision for yarn for yarn quality characteristics,

VIII RING SPINNING : -

Optimum level of pneumafil Suction pressure in Spinning.

Back Zone Setting in Ring Frame

Traveller Clearer setting in Ring Frame

Spacer for Different count in Ring Frame

Humidity Correction for Yarn Count at 800 F

IX DOUBLING : -

Doubled Yarn CSP

Count & Strength cv%

Yarn Unevenness (U%) and Imperfection

Yarn Quality Improvement Dur to doubling

Importance parameter’s for Two-For-One Twister

End Breaks ak Cheese Winding.


X GENERAL : -

Tolerence limit for pinion Changes

Relative Humidity & Temperature for Different Department

Shore Hardness of Top Roller Cots

Top Roller Pressure (Kg) - Fly frame

Top Roller Pressure (Kg) - Ring frame

Eccentricity of Bottom & Top Rollers

Yarn waste Sweep Waste & Invisible loss (%)

Usable waste % for Good working

Shade variation in dyed fabric

Fibre properties Requires to Produce Cotton Fabric with a DE value of 1.0

XI CONVENTIONAL CONE WINDING AND REELING : -

Slub Catcher setting at cone winding

Tension Weight in winding

End Breaks per one lakh meter for good working

Number of clearer cuts in auto winder

Rewinding breaks for electronically cleared & spliced Yarns

Variation in the number of threads in Hsnk & Weigtht of Bundle,Bale & Cone.

XII ROTOR SPINNING : -

Mixing for Open-End Yarn

Trash content (%) in Card Sliver meant for Rotor Spining

Ends Break in Rotor Spining / 100 Rotor Hours.

CSP for OE Yarns

Unevenness & Imperfection in OE Yarns

Count & Strength variation in OE Yarns

Recommended Rotor diameter

Elongation & Hairiness of Rotor Yarns

XIII MAN-MADE FIBRES AND BLENDS : -

Typical properties of Man-Made fibres

Quality Attributes of P/C Yarns

Quality Attributes of P/V Yarns

Quality of Ring & Rotor spun Yarns made out of Lyocell fibre

Hairiness values (Hairs/m. with Hair length Greater than 3 mm)

Norms of OE Man-Made fibres & Blended Yarns

Processparameters to beAdopted During Processing of blends

Blow Room

Speeds in Cards

Setting in SHP Cards

Setting in HP Cards

Precauyion for processing Tinted MAN – MADe fibres

Preventive measures to Avoid Coiler Choking

Process parameters in Draw frame

Drawframe sliver Unevenness (U%)

Speeds, Setting and Twist in Fly Frame processing

Roving Unevenness (U%)

Process parameters in Ring frame

Twist Multiplier for yarns from Man-Made fibres & Blends

Twist Setting

Shore Hardness on Top Roller Cots.


XIIV NORMS FOR EXPORT ORIENTED SPINNING MILLS (EOUs) : -

Mixing & Blow Room

Quality characteristics of cotton used for export yarn ( HVI Measurement )

Spinning - Prepatory process

Nep level in card & comber sliver

Unevenness (U%)

Drawframe sliver CV%

Charactristics of good quality export yarns

Process parameter in speed frame in exporting mills

Process parameter in Ring frame in exporting mills

Process parameter in Autowinders in exporting mills

Composition of wax for optimum performance


PAGE No - 1

I COTTON QUALITY

SPAN LENGTH

Span length parameters are based on the length of fibre measured at any random point on the fibre.

Only partial length of fibre is considered while computing span length.

Span length are fibre extension distances, not fibre length.

2.5 Span Length

2.5 % span length is the distance 2.5 % of the fibres extended from the clamp where they are

caught at random along their length. This length closely agrees with the staple length as

determined by the American Classers. Figure in Table 1 may be used as a guideline for classifying

Indians Cottons :

TABLE - 1

Classification of Cottons Based On

2.5 % Span Length Values

Class 2.5 % Span Length Values

Expressed in

mm inch

Extra Long Staple 33.0 and above 1.30 and above

Long Staple 29.5 to 32.5 1.15 to 1.29

Medium Staple 25.0 to 29 0.98 to 1.14

Short Staple - A 20.5 to 24.5 0.81 to 0.97

Short Staple - B 20.0 and below 0.80 and below

50 % Span Length

50 % span length is a distance 50 % of the fibres caugth at random extended from the clamp

along their lengths .

Unifimity Ratio

Uniformity ratio is defined as the ratio of 50 % span length to 2.5 % span length expressed as a

percentage . This ratio is a measure of the length variability of the cotton .

The ratings for uniformity ratio as follows :

50% : Good

45% : Average

43% : Poor

Mean Length

The average length of all fibres in the sample based on mass - length data .

Upper - Half - Mean Length

The mean length by number of the longer one half of the fibres by weight , as determined by HVI .

Upper - Half - Mean Length is nearly equal to 2.5 % span length .

Unifimity Index

The ratio betwwen the mean length and the upper half mean length expressed as a percentage .

Mean Length X 100

UI = Upper half mean length


PAGE No - 2

Gradiation of Uniformity Index ( UI )

Below 77 : Very low

77 - 79 : Low

80 - 82 : Medium

83 - 85 : High

86 and above : Very high

Micronaire and Maturity

The ratings of the micronaire and maturity values given below can be used as guideline .

Micronaire values Maturity Coefficient

3.0 : Fine 0.80 : Good

4.0 : Average 0.75 : Average

5.0 : Coarse 0.65 : Poor

Fibre Strength

The tenacity of the cotton obtained at 3 mm . Guage length can be rated on the following basis

Rating Pressley Stelometer

( 1000 lb / sq . In ) ( g / tex )

High 75 30

Average 60 24

Low 45 18

SAMPLING FROM BALES OF COTTON

( BULK SAMPLE )

When relatively large number of bales of cotton belonging to a given variety are purchased ,

a few bales may be chosen at random as representing the bulk . Table 2 gives the number of

bales to be chosen from the a lot .

TABLE - 2

Sampling Procedure for Bales

Bulk Size Sample Size

( Bales ) ( Bales )

Upto 50 2

51 to 100 4

101 to 150 7

151 to 300 13

301 to 500 20

501 to 1000 32

1001 to above 40

The number of tests required to arrive at a realastic estimate of the various fibre properties and

the critical are given in Table 3 .


PAGE No - 3

TABLE - 3

No . Of Tests and Critical Difference % for Various Fibre Properties

Type of tests No of Tests Critical Testing

and condition Difference ( % ) Instrument

Effective Length 2 Patterns/Sample 4 Baer sorter

Mean Length 2 Patterns/Sample 4 Baer sorter

2.5 Span Length 4 Combs / Sample 4 HVI

& upper half mean

length

50 % span length 4 Combs / Sample 4 HVI

Uniformity ratio & 4 Combs / Sample 5 HVI

Uniformity Index

Micrinaire Value 4 Plugs / Sample 6 HVI

Fibre Strength at 10 Breaks/Sample 5 Stelometer or

3 mm guage length Pressley

Maturity Coefficient 600 Fibres/Sample 7 Microscope

Trash Contents 8 Tests / Sample 7 Trash Analyser

If , for example , fibre properties between two cottons differ by more than the critical difference

values , then the difference should be regarded as significient , that is , the two cottons may be

taken to differ in the perticular fibre property .

Quality of Indian Cotton

Important quality characterstics of some of th major Indian Cottons are given in Table - 4 .

TABLE - 4

Fibre Properties of Some Indian Cottons

( Measured by Conventional Testing Instruments )

Cotton 2.5 Span Uniformity Range of Micro- Tenacity Trash

Length Ratio naire value (3mm G) %

( mm ) ( % ) ( ug/inch ) Stelometer

( g / tex )

Short Staple - B

( 20 mm And below )

RG 8 (Sriganganagar) 17.0 51.0 7.0 - 7.4 13.2 5.5

Bengal Deshi 17.7 49.8 6.8 - 7.2 15.2 7.0

Comillas 18.8 48.0 7.2 - 8.1 16.0 8.0

LD 491 (Abohar) 18.9 52.0 7.3 - 7.7 14.9 6.5

LD 327 (Abohar) 19.4 47.0 7.0 - 7.6 14.8 8.0


PAGE No - 4

TABLE - 4 ( Contd.)



2.5 Span Uniformity Range of Tenacity Trash

Cotton Length Ratio Micronaire (3mm G) %

( mm ) ( % ) value Stelometer

( ug/inch ) ( g / tex )

Short Staple - A

( 20.1 - 24.9 mm )

Wagad 21.2 50.0 5.5 - 7.0 15.5 6.0

Desi ( Bharuch ) 22.3 51.0 5.7 - 6.1 18.4 5.0

SRT 1 ( Bodeli ) 22.9 51.0 3.5 - 3.9 18.8 5.6

G. Cot. 12 23.0 47.7 4.2 - 5.0 15.7 8.0

RST 9 (Sriganganagar) 23.2 51.0 5.2 - 6.0 20.9 6.6

Suyodhar 12 23.3 45.9 5.0 - 5.5 18.4 8.0

F - 414 23.4 49.4 3.8 - 4.2 20.2 7.0

LH 900 ( Abohar ) 23.6 47.0 5.0 - 5.2 16.4 8.0

Digvijay(Maha) 23.7 48.9 3.5 - 4.0 21.1 6.0

G. Cot. 17(Bharuch) 23.7 51.0 4.2 - 4.6 23.8 4.2

Gujarat 17 (Kapadwanj) 23.7 52.0 4.5 - 4.9 25.3 4.7

V - 797 24.1 47.1 4.2 - 4.8 18.0 9.0

G.Cot.15 (Amreli) 24.1 52.0 4.9 - 5.1 20.4 5.9

Jayadhar 24.1 47.6 5.0 - 5.6 17.8 6.0

J - 34 24.3 45.3 3.6 - 4.4 19.0 9.0

Digvijay(Bharuch) 24.4 48.0 4.9 - 5.1 23.6 4.4

Bikareri Narma 24.7 49.6 3.6 - 4.4 18.8 -

H - 777 24.7 47.4 3.8 - 4.2 20.7 -

SRT 1 ( Maha ) 24.8 46.7 4.2 - 4.6 18.1 6.0

G.Cot.10 (Surat) 24.8 47.0 3.6 - 4.6 19.5 6.3

Medium Staple

( 25.0 - 29.0 mm )

LH 1556 (Abohar) 25.0 48.0 4.4 - 4.8 19.9 12.3

G.Cot. 13 (Dhanduka) 25.3 49.0 5.2 - 5.5 21.0 3.0

NHH 44 26.3 46.0 3.1 - 4.5 21.0 6.0

Khandwa 2 (Khandwa) 25.3 47.0 4.0 - 4.4 18.0 6.8

Digvijay (Kapadwanj) 25.7 52.0 3.8 - 4.2 24.4 5.0

Hybrid 6 (Surat) 26.0 49.0 3.3 - 3.9 20.6 6.6

G.Cot. 13 26.0 49.4 4.2 - 5.0 17.8 4.0

Sanjay (Amreli) 26.1 48.0 4.5 - 4.8 22.9 6.5

JKHY - 1(Khargone) 26.2 49.0 3.6 - 3.8 23.0 6.0

Laxmi 26.3 45.9 3.6 - 4.0 18.2 7.0

DHY 286 (Akola) 26.5 51.0 3.9 - 4.3 21.5 8.0

Deviraj ( Junagadh) 27.4 42.0 2.7 - 3.7 18.2 11.1

G. Agethi 27.4 46.6 3.8 - 4.2 18.8 8.0

G.Cot Hy 10 (Surat) 27.8 46.0 3.4 - 3.8 23.6 2.9

1007 27.9 44.6 3.7 - 4.0 21.5 6.0

MCU-7 28.5 46.0 3.8 - 4.2 20.3 6.0

MECH 28.7 47.0 3.7 - 4.1 21.4 4.0

LRA - 5166 28.8 50.0 4.0 - 4.5 19.8 7.0


PAGE No - 5 TABLE - 4 ( Contd.)



2.5 Span Uniformity Range of Tenacity Trash

Cotton Length Ratio Micronaire (3mm G) %

( mm ) ( % ) value Stelometer

( ug/inch ) ( g / tex )

Long Staple

( 29. 1 to 32.9 mm )

Sankar - 4 29.5 49.0 3.6 - 4.0 22.2

Sankar - 6 30.1 48.4 3.7 - 4.2 20.9 5.0

Hybrid - 4 30.3 47.2 3.6 - 4.2 20.5 5.0

G.Cot DH 9 (Surat) 32.0 49.0 3.9 - 4.5 28.6 9.0

MCU 5 (TN) 32.5 45.7 3.0 - 3.5 20.8 5.0

Extra - Long Staple

( 33 mm and above )

DCH - 32 (Hubli) 34.7 46.0 2.7 - 3.1 26.6 9.2

Suvin 36.5 49.5 2.7 - 3.1 30.0 2.0

Note : Based on trade varieties

FIBRE QUALITY INDEX : DEFINATION

To decide the quality characteristics of cotton required for spinning of different counts with

desired CSP values, a single measure for the overall quality of cotton ha been established by SITRA.

This measure, known as Fibre Quality Index (FQI.), is arrived at from the following formula :

FQI = Lsm

f

Where L 50% Span length in mm

s Bundle strength in g/tex at 3 mm guage length (Stelometer)

m Maturity coefficient

f Fibre fineness ( Micronaire value)

YARN CSP AND FQI :

The acievable yarn CSP for a given FQI of cotton ( Fibre properties tested using conventional

testing Instruments) under optimum twist multiplier is given by the equation :

Lea CSP = [320 ( f FQI +1) - 13 C ] for Carded couts.

Lea CSP = [320 ( FQI +1) - 13 C ](1+W/100) for Combed couts.

Where C =count spun

W=% Noil extracted during combing

If maturity coefficient values are not readily available , as a rough approximAtion, the yarn CSP

values may be arrived at from the following formula :

CSP = 275 (Ls/f) + 320 - 13 C

The formula will be subject to large error, if the maturity coefficient of the mixing is very low.

While applying this expression , it should be insured that the mixing used is composed of

compatible components.Mixing with hybrid cotton with a low micronaire value of a 3.0 or mixing with high

proportion of soft waste, flat strips and comber noils will not lend themselves to a meaningful application

of this expression.


PAGE No - 6

TM for maximum strength :

T max = 50 - L + f

9

FIBRE YARN RELATIONSHIP USING HVI/FMT MEASURED FIBRE PROPERTIES :

SITRA has also devoloped prediction expressions connecting fibre properties measured by

high volume Instruments (HVI) shirely Fineness Maturity Tester ( Shirely FMT) with yarn CSP. The

expression connecting Les CSP with fibre properties measured by HVI /FMT is given below :

Lea CSP = 280 (FQI) + 700 - 13 C For Carded counts. …..………………(1)

& Lea CSP = {280 (FQI)+ 700 - 13 C} { 1+W/100} For Combed counts. ……(2)

Where FQI = Lsm

f

" L,s & f" are measured using HVI test sustem and "m" using shirely FMT.

L = 50% Span length (mm)

s = Bundle Strength (g/tex)

f = Fineness (Micronaire Value) &

m =Maturity Ratio

If maturity ratio values ( by shirely FMT ) are not readily available,then, as an approximation, the

yarn CSP values may be arrived at from the following formula

Lea CSP = 250 (Ls/f) + 590 - 13 C

FIBRE PROPERTIES FOR WARP YARNS :

Norms for fibre properties of cottons required to spin yarns with three diffenrent levels of CSp are

given in Tables 5 & 6 .

TABLE - 5

NORMS FOR FIBRE PROPERTIES TO SPIN YARNS

WITH 3 DIFFERENT LEVELS OF csp

UNDER GOOD WORKING CONDITION

( Fibre properties measured by HVI Test System)

(Coarser Fibre)Count Yan 2.5.% 50.00% Fibre Micronaire

(Nec) CSP Span Span Strength Value

Length Length ( g/tex ) (ug/inch)

(mm) (mm)

(I) (L) (s) (f)

20s 1850 22.5 12.00 13.5 4.4

2050 23.5 12.30 15.0 4.4

2200 24.5 13.50 18.2 4.4

24s 1900 23.0 12.50 14.7 4.4

2100 24.0 12.65 17.0 4.4

2300 25.5 14.50 19.8 4.4

26s 1950 24.0 13.00 15.3 4.3

2150 25.0 12.80 18.0 4.3

2350 26.5 15.00 20.0 4.3

30s 2000 25.0 13.50 15.8 4.1

2200 26.5 13.50 18.5 4.1

2400 27.0 15.20 21.0 4.1


PAGE No - 7

36s 2000 26.0 13.50 16.2 3.9

2200 27.5 14.00 19.0 3.9

2400 28.0 15.50 21.0 3.9

40s 2000 27.5 14.00 16.2 3.8

2200 28.5 14.20 20.0 3.8

2400 29.0 15.40 21.5 3.8

44s 2000 27.5 14.00 17.0 3.8

2200 28.5 14.50 20.5 3.8

2400 30.0 16.50 21.0 3.8

50s 2000 28.0 14.30 18.0 3.8

2200 30.0 15.00 21.5 3.8

2400 31.0 17.10 21.5 3.8

55s 2050 29.5 15.30 18.8 3.8

2250 31.0 15.50 23.0 3.8

2450 31.5 17.40 23.2 3.8

60s 2100 30.0 15.30 20.8 3.8

2300 32.0 16.30 24.0 3.8

2500 32.5 17.50 25.3 3.8

70s 2100 30.5 15.50 22.4 3.7

2300 33.5 17.00 25.0 3.7

2500 34.0 17.45 27.0 3.7

80s 2100 31.5 16.50 22.8 3.6

2300 35.0 18.00 25.5 3.6

2500 36.0 19.00 26.5 3.6

Example :

Suppose a mill wants to produce 30S yarn with 2200 csp , then the fibre properties of mixinng

which will meet their requirement are ,

50% Span length (mm) 13.5

Fibre Strength (g/tex) 18.5

Micronaire value (ug/inch) 4.1

Incase one of three fibre properties ( as mentioned above) of cotton is lower than the standard

the same may be compensated for by the corrosponding increase in other fibre properties so as to

produce 30S yarn of 2200 CSP as desired.

TABLE - 6





(Finer Fibre)

Count Yan 2.5.% 50.00% Fibre Micronaire



(mm) (mm)

(I) (L) (s) (f)

20s 1850 21.0 10.50 13.5 4.4

2050 22.0 11.00 15.0 4.4

2200 25.0 13.00 18.2 4.4

24s 1900 22.0 11.00 14.0 3.9

2100 24.0 12.00 15.0 3.9

2300 26.0 14.00 16.8 3.9


PAGE No - 8

TABLE - 6 ( Contd.)





(Finer Fibre)

Count Yan 2.5.% 50.00% Fibre Micronaire



(mm) (mm)

(I) (L) (s) (f)

26s 1950 23.0 11.50 14.5 3.8

2150 24.5 12.40 15.5 3.8

2350 26.5 14.50 17.8 3.8

30s 2000 23.5 12.00 14.8 3.7

2200 25.0 12.80 15.0 3.7

2400 27.0 15.00 18.0 3.7

36s 2000 24.0 12.75 15.1 3.5

2200 26.0 13.00 16.5 3.5

2400 28.0 15.50 18.0 3.5

40s 2000 24.5 13.00 15.1 3.4

2200 27.0 14.00 17.5 3.4

2400 28.8 16.00 18.0 3.4

44s 2000 25.0 13.50 15.4 3.3

2200 27.0 14.00 18.5 3.3

2400 29.0 16.00 18.7 3.3

50s 2000 26.0 14.00 16.0 3.3

2200 28.0 14.30 19.5 3.3

2400 29.5 16.50 19.4 3.3

55s 2050 26.5 15.00 17.2 3.3

2250 29.0 15.00 21.0 3.3

2450 30.0 17.00 21.2 3.3

60s 2100 27.5 15.50 17.9 3.2

2300 30.0 16.00 21.8 3.2

2500 31.0 17.50 22.0 3.2

70s 2100 28.5 15.50 19.3 3.2

2300 32.0 16.00 23.0 3.2

2500 32.5 17.50 23.3 3.2

80s 2100 29.5 16.00 19.5 3.0

2300 33.0 16.50 23.0 3.0

2500 33.5 17.80 23.4 3.0

90s 2100 30.0 16.00 22.3 3.1

2300 33.5 16.50 25.5 3.1

2500 34.0 18.50 25.5 3.1

100s 2100 31.0 17.00 24.0 3.2

2300 34.5 17.20 27.0 3.2

2500 35.5 19.50 27.0 3.2


PAGE No - 9

TABLE - 7

COTTONS USED FOR WARP YARNS

Count Range Name of Cotton

1s - 10s V797,GC0T21,JAYADHAR,Y1

11s - 20s NHH 44,H8, GCOT17

21s - 30s NHH 302, GCOT16, H10, DHH 11

31s - 40s LHH 144, JKHY, H6, LK861 , S6

41s - 60s S4, MCU5

61s - 80s MCU5, DCH 32

81s - 120s DCH 32, SUVIN

Hosiery Yarns

TABLE - 8

NORMS FOR HOSIERY YARN

Fibre Properties Yarn prpperties

( Conventional Testing Instrument)

Count .2.5% Unf Mic Bundle Strength

(Ne) Span Ratio Value at 3 mm

Length (%) (ug/inch) Guage (g/tex) Lea U% imp. / Km

(mm) Stelometer CSP Thin Thick Neps

Carded 47 4.1 19 1710 11 10 90 240

20s 27 48 4.1 20 1800 12.5 25 175 500

30s 28 48 3.8 20 1900 13.5 75 275 800

40s 30

Combed

30s 30 48 3.8 20 2050 10 2 38 100

40s 31 48 3.6 22 2050 10.5 3 77 200

60s 31 48 3.6 22 2100 11.5 15 70 195

80s 33 48 3.0 23 2200 12.5 30 100 290

Note : - The receint varities of cotton are about 10% finer & also less mature almost to the same extent.

The maturity coefficient of the cotton used for spinning hosiery yarn are typically around 0.75 - 0.8

FLY LIBERATION DURING KNITTING

25 mg (maximum) per Kg of yarn knitted

NORMS FOR PROCESS PROFICIENCY

Process Proficiency Based on Lea CSP

For a given mixing the ration of actual CSP obtained to that of the expected CSP, expressed as

percentage is called Process Proficiency

( Norms : 100 Good, 95 Average, 90 Poor )

Process Proficiency Based on Yarn Unevenness

For a given mixing the ratio of actual U% to that expected U% expressed as percentage is called

Process Proficency

( Norms : 100 Good, 105 Average, 110 Poor )


PAGE No - 10 Yarn Unevenness

The relationship between the drafting quality of a cotton (Q) & yarn unevenness (U) is given by

(d-1) .+a(d-1) +Ur2

U2 = QNE d

Where U = Yarn unevenness (U%)

Q= 29.4 [F/L]2

F = Fineness / maturity coefficient

L = 50% span length (mm)

Ne = yarn count

d = Draft in ringframe

Ur = Roving unevenness (U%)

a = Contribution by ringframe to yarn unevenness

a' assume a value of 3.5 under good working condition

FIBRE PROPERTIES FOR DIFFERENT LEVELS OF YARN U % : -

Fibre properties of mixing (measured by conventional testing instruments) for spinning counts

with different levels of yarn U% can be determined from table 9 & table 10.

TABLE - 9

U% EXPECTED UNDER GOOD WORKING CONDITION FOR DIFFERENT COTTONS

(CARDED COUNTS)

Q* Counts Q* Counts

100s 80s 60s 40s 30s 20s

1.5 16.2 15.1 13.9 4 15.7 14.3 12.3

1.6 16.5 15.3 14.1 4.2 15.9 14.5 12.5

1.7 16.8 15.6 14.3 4.4 16.2 14.7 12.6

1.8 17.1 15.8 14.5 4.6 16.4 14.9 12.8

1.9 17.4 16.1 14.7 4.8 16.6 15.1 12.9

2 17.6 16.3 14.9 5 16.9 15.3 13.1

2.1 17.9 16.5 15.1 5.2 17.1 15.5 13.2

2.2 18.2 16.8 15.3 5.4 17.3 15.6 13.3

2.3 18.4 17 15.5 5.6 17.5 15.8 13.5

2.4 18.7 17.2 15.7 5.8 17.8 16 13.6

2.5 19 17.4 15.9 6 18 16.2 13.8

2.6 19.2 17.7 16.1 6.2 18.2 16.4 13.9

2.7 19.5 17.9 16.1 6.4 18.4 16.5 14

2.8 19.7 18.1 16.4 6.6 18.6 16.7 14.2

2.9 20 18.3 16.6 6.8 18.8 16.9 14.3

3 20.2 18.5 16.8 7 19 17 14.4

3.1 20.4 18.7 16.9 7.2 19.2 17.2 14.6

3.2 20.7 18.9 17.1 7.4 19.4 17.4 14.7

3.3 20.9 19.1 17.3 7.6 19.6 17.5 14.8

3.4 21.1 19.3 17.4 7.8 19.8 17.7 14.9

3.5 21.4 19.5 17.6 8 20 17.9 15.1

3.6 21.6 19.7 17.8 8.2 20.2 18 15.2

3.7 21.8 19.9 17.9 8.4 20.4 17.2 15.3

3.8 22 20.1 18.1 8.6 20.5 18.3 15.4

3.9 22.2 20.3 18.2 8.8 20.7 18.5 15.6

Draft 29 27 26 22 21 17

Note : - I) For Roving U % as indicated in Table - 45 .

ii ) For Draft in Ring Frame , as given under Table - 12 .

* The drafting quality of cotton From the point of view of yarn U % is determinerd by the measure

Q = 29.4 x ( F / L )2

The values of Q for Cottons with Different values of 'F'(=f/m) and 'L'(=50% span length) are given in

Sitra Norms For Spin. the Table 10 . For combed counts the values of F and L should correspond to those of combed sliver .

PAGE No - 11

TABLE - 10

Q Factors for Different Values of ' F ' and ' L '

L \ F 3.6 4.0 4.4 4.8 5.2 5.617.0 1.3 1.6 2.0 2.3 2.7 3.2

16.5 1.4 1.7 2.1 2.5 2.9 3.4

16.0 1.5 1.8 2.2 2.6 3.1 3.6

15.5 1.6 2.0 2.4 2.8 3.3 3.8

15.0 1.7 2.1 2.5 3.0 3.5 4.1

14.5 1.8 2.2 2.7 3.2 3.8 4.4

14.0 1.9 2.4 2.9 3.5 4.1 4.7

13.5 2.1 2.6 3.1 3.7 4.4 5.1

13.0 2.3 2.8 3.4 4.0 4.7 5.5

12.5 2.4 3.0 3.6 4.3 5.1 5.9

12.0 2.6 3.3 4.0 4.7 5.5 6.4

11.5 2.9 3.6 4.3 5.1 6.0 7.0

11.0 3.1 3.9 4.7 5.6 6.6 7.6

10.5 3.5 4.3 5.2 6.1 7.2 8.4

10.0 3.8 4.7 5.7 6.8 8.0 9.2

Note : A mill Spines 60s carded counts , using a cotton with a 50 % span length ( L ) of 15.0 and fibre

finess / maturity coefficient ratio 4.0 then values of Q = 2.1 from the previous table , it is seen that yarn

U % expected for 60s carded count ( Q = 2.1 ) is 15.1 .

SITRA' s Prediction Expression for yarn unevenness Using HVI / FMT Measured Fibre

Properties : -

STRA has also developed a prediction expression connecting fibre properties measured by

HVI / Shirley FMT and yarn unevenness , ad the expression is given below : -

U2 = 21.5 ( F / L )

2 ( d -1/ d ) Ne + 4.1 ( d -1 ) + Ur

2

Where F = Micronaire value

Maturity Ratio ( FMT )

L = 50 % Span Length ( mm )

d = Draft in ring frame

Ne = Count Spun

Ur = Roving Unevenness

Norms for fibre properties to spin yarns with 3 differnt levels of U % under good working

conditions are given in Table 11 and 12 .

TABLE - 11

Norms for Fibre Properties to Spin Yarns With 3 Different

Levels of U % Under Good Working Conditions

( Fibre Properties Measured by HVI Test System )

( Coarser Fibres )

Count Yarn 50 % Span Maturity Micronaire Values

( Ne ) U % Length (mm ) Ratio ( ug / inch )

( L ) ( FMT ) ( f )20s 13.0 12.1 0.80 4.4

12.0 13.7 0.85 4.4

11.0 16.5 0.90 4.4

24s 13.5 12.3 0.80 4.4

12.5 13.5 0.85 4.4

Sitra Norms For Spin. 11.5 15.7 0.90 4.4

PAGE No - 12

TABLE - 11




( Coarser Fibres )



( L ) ( FMT ) ( f )

26s 13.5 12.5 0.80 4.3

12.5 13.8 0.85 4.3

11.5 16.0 0.90 4.3

30s 13.5 14.2 0.80 4.1

12.5 16.3 0.85 4.1

11.5 20.4 0.90 4.1

36s 13.5 14.8 0.80 3.9

12.5 16.8 0.85 3.9

11.5 21.5 0.90 3.9

40s 14.5 13.3 0.80 3.8

13.5 14.7 0.85 3.8

12.5 17.0 0.90 3.8

44s 14.5 12.5 0.85 3.8

13.5 13.5 0.90 3.8

12.5 15.5 0.95 3.8

50s 14.0 15.0 0.85 3.8

13.0 16.8 0.90 3.8

12.0 20.0 0.95 3.8

55s 14.0 15.6 0.85 3.8

13.0 17.5 0.90 3.8

12.0 21.0 0.95 3.8

60s 14.0 17.0 0.85 3.8

13.0 19.5 0.90 3.8

12.5 21.0 0.95 3.8

70s 14.5 17.3 0.85 3.7

13.5 19.5 0.90 3.7

13.0 21.0 0.95 3.7

80s 14.5 18.0 0.85 3.6

13.5 20.5 0.90 3.6

13.0 22.0 0.95 3.6

Example : -

For a mill to produce 60s yarn with 13.0 U % , the mixing used ougth to have

50 % span length ( mm ) = 19.5

Maturity Ratio = 0.9

Micronaire value = 3.8

Any deficiency in any of the three fibre quality characterstics can be compensated for by

corresponding improvement / increase in other fibre quality attributes so that the overall fibre quality is

maintained ( at the desired level) to spin yarns of required count with desired levels of U % .


PAGE No - 13

TABLE - 12




( Finer Fibres )



( L ) ( FMT ) ( f )

20s 13.0 11.4 0.75 3.9

12.0 12.8 0.80 3.9

11.0 15.5 0.85 3.9

24s 13.0 12.2 0.75 3.8

12.0 13.7 0.80 3.8

11.0 16.5 0.85 3.8

26s 13.0 12.5 0.75 3.7

12.0 13.8 0.80 3.7

11.0 17.0 0.85 3.7

30s 14.0 12.0 0.75 3.5

13.0 13.3 0.80 3.5

12.0 15.7 0.85 3.5

36s 14.0 12.8 0.75 3.4

13.0 14.0 0.80 3.4

12.0 17.0 0.85 3.4

40s 15.0 11.6 0.75 3.3

14.0 12.5 0.80 3.3

13.0 14.0 0.85 3.3

44s 15.0 10.9 0.80 3.3

14.0 11.6 0.85 3.3

13.0 12.8 0.90 3.3

50s 13.0 16.2 0.80 3.3

12.0 19.5 0.85 3.3

11.5 22.0 0.90 3.3

55s 13.0 17.0 0.80 3.3

12.0 20.5 0.85 3.3

11.5 23.0 0.90 3.3

60s 13.0 18.5 0.80 3.2

12.5 20.0 0.85 3.2

12.0 22.0 0.90 3.2

70s 13.5 19.0 0.80 3.2

13.0 20.0 0.85 3.2

12.5 22.0 0.90 3.2

80s 14.0 17.5 0.80 3

13.0 20.5 0.85 3

12.5 22.0 0.90 3

90s 14.5 18.5 0.80 3.1

14.0 19.0 0.85 3.1

13.0 23.0 0.90 3.1

100s 14.5 20.0 0.80 3.2

14.0 20.6 0.85 3.2

13.3 23.0 0.90 3.2


PAGE No - 14

ASSUMPTIONS

1 ) Draft in Ring Frame

20s to 26s 22

30s & 36s 27

40s & 44s 29

50s & 55s 31

60s 34

70s & 80s 35

90s & 100s 38

Relative Contribution of Fibre Properties to Yarn CSP and U %

TABLE - 13

Contribution to Yarn CSP

1 % Increase in Will change the

Yarn CSP by

50 % span length + 0.5 %

Fibre bundle Strength + 0.5 %

Micronaire - 0.5 %

Maturity coeffient + 0.5 %

Note : 1 % increase in 50 % span length will increase the yarn CSP by about 0.5 % .

TABLE - 14

Contribution to Yarn Unevenness

Unit Will increase Yarn U %

Increase in Approximately By

Q Ne / 2U

d a / 2U

a ( d - 1 ) / 2U

Ur Ur / U

Note : To illustrate , if roving U % is 5 and yarn U % is 15 , an increase of roving U % by 1 , that is from

5 to 6 , will increase yarn U % by about 0.33 .

Relationship Between Fibre Length Measured by Different Instruments

Length measures derived from Digital Fibrograph can be compared with Baser Sorter measurements

by making use of the regression equation of the form Y = mX + c .

TABLE - 15

Fibre Length Relationships

Y X m c

( mm ) ( mm )

BAER SORTER DIGITAL FIBROGRAPH

Effective length 2.5 % span length 1.013 4.39

Mean length 50 % span length 1.242 9.78


Note : If 2.5 % span length of a cotton as tested on digital fibrograph is 30mm , then the Baer Sorter

effective length is estimated to be 34.8 mm that is ( 1.013 x 30 ) + 4.39 .

PAGE No - 15

TABLE - 16

Relationship Between fibre Strength Measured by

Different Methods

S No. Test Method Relationship

I 'O' Guage Length Test

Pressley Strength in 2.3 x Stelometer

1000 lbs / sq.in ( g / tex )

Pressley Strength index 0.2 x Stelometer

( lbs / mg ) ( g / tex )

ii '3 mm' Guage Length Test

Pressley Strength in 2.5 x Stelometer

1000 lbs / sq.in ( g / tex )

Pressley Strength index 0.17 x Stelometer

( lbs / mg ) ( g / tex )

Illustration :

To find the expected pressley strength (3 mm.guage) of a cotton , given its Stelometer strength

(3 mm.guage) as 24.8 g / tex .

Pressley Strength in = ( 24.8 x 2.5 ) =62

1000 lbs / sq.in

The strength of the cotton if tested on pressley Tester would be 62000 lbs / sq.in .

Note : The conversion of fibre length and strength value as obtained from one method to another as

above is subject to apperiable errors , and hence should be taken only as an approximate estimate.

HVI Test System

HVI test system is widely used in E.O.Us as well as in leading exporting mills evaluation of Cotton

Quality . HVI system measures 7 important characterstics of cotton, and they are :

I) Length

ii) Length uniformity

iii) Micronaire

iv) Strength

v) Elongation

vi) Colour and reflectance

vii) Trash Content by optical determination .

About 100 Samples / shift of 8 hours ( each sample - 4 tests ) could be conveniently tested using

HVI . Length characterstics and micronaire value measured using HVI and conventional testing Instruments

( Fibrograph 530 / Sheffield Micronaire ) agree well with each other .

In the case of strength assessment , there is some difference between HVI measurement and

measurement based on Stelometer . To narrow down this difference in tenacity values, care has to be

taken with reference to the following aspects .

Sitra Norms For Spin. - Both the instruments ( HVI as well as Stelometer ) are to be calibrated using the same calibration cotton.

- Testing of cotton on both the instruments must be carried out at the same humidity conditions .

PAGE No - 16

Trash in Cotton

The trash allawable in cotton to produce a card sliver of good quality is givn in Table - 17 .

TABLE - 17

Trash in Cotton ( % )

Count 20s 30s 40s 60s 80s 100s

Trash 5.0 4.0 3.5 3.0 2.5 2.0

Note : Because of the wide fluctuations in trash content, eight tests are required for arriving at a

reliable estimate. The critical difference for 8 tests per sample is of the order of 7 % of trash content .

NEP CONTENT OF INDIAN AND FOREIGN COTTONS

TABLE - 18

Nep Contnt Of Some Indian Cottons

S No . Cotton Neps / g Neps SCN / g SCN

Variety ( Range ) Size ( m) (Range ) Size ( m)

( Range ) ( Range )

1 LRA 96 - 167 709 -780 2 - 22 1075 - 1545

2 MCU -5 91 - 135 709 -820 4 - 31 1296 - 1428

3 MECH 91 - 143 654 - 733 14 - 24 975 - 1268

4 DCH -32 98 -315 680 - 800 16 -23 1108 - 1825

5 S - 6 122 - 192 700 - 800 11 - 47 933 - 1305

6 J -34 94 - 243 695 - 856 9 - 26 1025 - 1295

7 RCH 56 - 100 710 - 780 6 - 17 978 -1156

8 NHH - 44 118 - 176 696 - 829 18 - 34 975 - 1519

TABLE - 19

Nep Contnt Of Some Imported Cottons

S No . Cotton Neps / g Neps SCN / g SCN

Variety ( Range ) Size ( m) (Range ) Size ( m)

( Range ) ( Range )

1 SUDAN 86 - 182 669 -762 0 -10 911 - 1025

2 Africans 215 - 253 725 - 846 23 - 49 1076 -1720

3 CIS 213 - 246 710 - 982 18 - 44 1172 - 1420

4 Australian 206 - 231 712 - 824 8 - 22 1010 - 1376

5 GIZA - 75 94 - 188 612 - 760 4 - 11 995 - 1126

6 PLEBE 184 - 312 675 - 698 15 - 26 1061 - 1650

7 GIZA - 86 128 - 198 600 - 688 2 - 14 700 - 1425

8 GIZA - 89 90 - 155 682 - 753 2 - 17 1025 - 1375


PAGE No - 17

II BLOW ROOM

TABLE - 20

Trash in Lap ( % )

Mixing Norms

Good Average Poor

20s 2.00 2.20 2.40

30s 1.80 2.00 2.20

40s 1.50 1.75 2.00

60s 1.35 1.50 1.65

80s 1.25 1.40 1.55

100s 1.00 1.10 1.20

TABLE - 21

Cleaning Efficiency ( % ) and Lint in Waste ( % )

In modern Blow Room Lines

Trash in No. of Cleanings

Cotton ( % ) Beating Efficiency

Points ( % )

5.0 and above 5 60 - 65

3.0 to 4.9 4 55 - 60

1.0 to 2.9 3 50 - 55

Cleanings Efficiency ( % ) = % trash in cotton - % trash in lap x 100

% trash in cotton

Note : In modern Blow Room lines, greater importance is given to opening than to higher cleaning

action and hence , the cleaning efficiency will be lower at about 55 % to 65 % . However , excess

trash in lap is removed by the attachments like pre-carding and post-carding segments om modern

high production cards .

Blow Room Waste % ( Excluding Gutter Loss )

About the same as the trash in cotton for good cleaning efficiency .

Gutter loss will vary between 0.5 % ( fine mixings ) to 1.0 % ( coarser mixings )

TABLE - 22

Cleaning Efficiency of Individual Beating Points

( For Good Working )

Type Cleaning

Efficiency ( % )

Mono Cylinder 25 - 30

Axifloe Cleaner 15 - 20

ERM Cleaner 25 - 30

Step Cleaner 30 - 35

Saw Toothed Operner 25 - 35

Cleanomat 20 - 35*

RK Cleaner 15 - 20

RN Cleaner 15 - 20

RV Cleaner 15 - 20

RSK Beater 20 - 25

2 Bladed Beater 10 - 12

Sitra Norms For Spin. 3 Bladed Beater 12 - 15

Kirschner Beater - 3 lags 8 - 10

Kirschner Beater - 6 lags 15 - 20

Note : Lint in waste of the individual beatings points will be in the range of 20 to 30 % .

* According to the number of beaters employed in the syastem .

PAGE No - 18

Fibre Rupture and Nep Generation in Blow Room

If 2.5 % span length or upper half mean length of lap drops off by more than 4 % as compared with

that of mixing , fibre rupture could be suspected in blow room line. The increase in neps due to processing

the cotton has to be kept below 60 - 70 % for optimal blow room performance .

TABLE - 23

C . V . % of Blow Room Lap

Wrapping Length Good Average Poor

Full Lap 0.6 0.8 1.0

1 m Length within ) 1.0 1.5 2.0

a lap )

Note : For optimum performance , the lap rejections should not exceed 3 %

- In the case of modern blow room lines , full lap CV will be lower by 0.25 % and 1 m CV will be

lower by 0.2 to 0.5 % .

TABLE - 24

Running - in - time of Bale Opener With Respect to scutcher

Type of Blow Room Running - in - time ( % )

1. With blending machine 75

in the time

2. Without blending machine 90

in the time


PAGE No - 19

III CARDS

TABLE - 25

Trash Content in Card Sliver ( % )

% Trash in Mixing 2 to 3.4 3.5 and above

% Trash SHP 0.20 - 0.40 0.30 - 0.50

in Sliver

HP 0.15 - 0.25 0.20 - 0.30

VHP 0.10 - 0.20 0.05 - 0.10

TABLE - 26

Combined Cleaning Efficiency of Blow Room and Cards ( % )

Combition

Trash in mixing Blow Room Blow Room Blow Room

and SHP and HP and VHP

Cards Cards Cards

2.0 to 3.4 85 - 90 88 - 93 90 - 95

3.5 & above 87 - 92 90 - 95 93 - 98

TABLE - 27

Waste ( % ) in Cards

Mixing Type of Lickner in Flat Others Total

Cards Droppings Strips

20s to 40s SHP 1.5 2.5 0.5 4.5

HP 1.8 3.0 1.2 6.0

VHP 2.0 3.5 1.5 7.0

50s to 100s SHP 1.2 2.3 0.5 4.0

HP 1.5 2.8 1.2 5.5

VHP 1.8 3.0 1.2 6.0

Variation in waste permissible between Cards = Average ± 0.5 %

TABLE - 28

Nep in Card Web in Semi - High - Production Cards

Mixing Neps per 500 sq. cm.

Good Average

20s to 40s 20 30

60s 12 18

Sitra Norms For Spin. 80s and Finer 8 12

PAGE No - 20

TABLE - 29

Estimation of Neps in Card Web Using Shirley Template

No.of Neps No.of Neps No.of Neps No.of Neps

Cells Per Cells Per Cells Per Cells Per

With 500 With 500 With 500 With 500

Neps sq. cm . Neps sq. cm . Neps sq. cm . Neps sq. cm .

1 2 9 24 17 53 25 103

2 5 10 27 18 58 26 112

3 7 11 30 19 63 27 122

4 9 12 34 20 69 28 134

5 12 13 37 21 75 29 149

6 15 14 41 22 81 30 166

7 18 15 45 23 87 31 188

8 21 16 49 24 95 32 220

TABLE - 30

Neps in Cards Sliver * ( VHP Cards )

Mixing Neps / g

Good Average

20s to 40s 50 75

50s and finer 75 100

* Based on Instrumental Analysis

- VHP Cards - Very high Production cards are capable of cylinder speeds upto 450 rpm and doffer

speeds upto 180 m / min .

TABLE - 31

Cards Settings for Cotton

HP Cards

Setting Point Setting ( in mm )

Feed roller to feed plate 0.125

Feed plate to licker - in 0.500

Lickner - in to mote knife I 0.450

Lickner - in to mote knife II 0.550

Lickner - in to combing segment I 0.400

Lickner - in to combing segment II 0.500

Lickner - in to Lickner - in undergrid 0.550

Lickner - in to Cylinder 0.200

Cylinder to back plate - Top 0.350

- Bottom 0.450

Cylinder to carding plate - Top 0.325

- Bottom 0.375

Cylinder to Cylinder - under - grid 0.55 , 1.3 , 1.3 ,

2.2 , 8.0

Cylinder to flats 0.25, 0.2, 0.2,0.2

Cylinder to front plate - Top 0.650

- Bottom 0.550

Sitra Norms For Spin. Cylinder to front bottom plate 0.450

Cylinder to Doffer 0.100

Doffer to take off roller 0.125

Take off roller to grooved roller 0.125

Grooved roller to Crush Roller 0.250

PAGE No - 21

For 4th generation of cards , feed plate to lickerin setting of 0.5 mm to 0.6 mm ( lap fed ) ,

0.6 mm to 0.8 mm ( chute fed ) and cylinder to flat setting of around 0.2 mm give better results

in terms of fibre individualisation .

TABLE - 32

Nep Removal Efficiency of Cards

Type of Cards Nep Removal

Efficiency ( % )

SHP 40

HP 60

VHP 80

TABLE - 33

Unevenness of Card Sliver

Type of Cards Unevenness

( U % )

SHP 4.5

HP 4.0

VHP 3.5

Note : CV of card sliver based on 5 m wrappings : 3 - 3.5 %


PAGE No - 22 IV COMBERS

Comber Preparatory

Process Sequence : I) Sliver lap - Ribbon lap

ii) Draw frame - super lap

Toatal number od doublings : Minimum of 120

- Higher the Number of doublings, better will be the sliver quality .

Linear density of lap : 50 - 55 g / m

CV of 1 m length of lap = 2.0 %

Sliver Lap :

Braek Draft : 1.1

Total Draft : 1.5

Ribbon Lap :

Braek Draft : 1.0 to 1.1

Total Draft : 6.0 to 6.5

Combing Efficiency

Combing efficiency is generally assessed by the improvement in fibre length achived with respect

to that of the input material .

Combing Eficiency ( % ) = 50 % span length of comber sliver - 50 % span length of comber lap x

per unit Noil extraction 50 % span length of comber lap

100

% noil extraction during combing

TABLE - 34

Norms for Combing Efficiency

Rating Combing Efficiency ( % ) per unit of Noil Extraction

Upto 12 % 13 to 20 %

Noil Extraction Noil Extraction

Good 0.6 0.8

Average 0.5 0.7

Poor 0.4 0.6

Note : 1) Under good working conditions , for every 1 % increase in comber noil , yarn lea strength will

increase by 1 % and the yarn evenness will improve by 0.15 U % . In modern high speed combers

, the improvements will be some what higher than these values .

2) Apart from machinery condition and processing parameters used, the combing efficiency also

depends on the short fibre contents of mixing . Higher the short fibre content, better will be the

Sitra Norms For Spin. combing efficiency .

Variation in Comber Noil

Between Combers : ± 0.5 %

Between Heads within a comber : ± 0.5 %

PAGE No - 23 TABLE - 35

Nep Removal Efficiency Of Combers

Noil Extraction Nep Removal

( % ) Efficiency ( % )

12 - 14 45

15 - 17 55

18 - 20 70

Note :

Nep Removal Efficiency ( % ) = Neps / g in comber lap - Neps / g in comber sliver x 100

Neps / g in comber lap

TABLE - 36

Process Parameters for Combers

Parameters Optimum Value / Mode

12 - 16 % 17 - 20 %

Noil Noil

Type of feed Forward Backward

Feed Length ( mm / nip) 5.0 to 6.0 4.0 to 5.0

Lap Weight ( g / m ) 50 to 55 50 to 55

Setting Between

Halflap & Bottom

Nipper ( mm ) 0.35 0.35

While using combers with extra fleece nipper ,

I) Noil level could be reduced by 2 to 3 % as compared to that extracted in conventional

combers for the same level of sliver / yarn quality .

ii ) For the same level of noil extraction , combers with extra fleece nipper yield about 30 %

fewer imperfecions .

iii) For the same level of noil extraction and yarn quality , combers with fleece nipper could be

run at about 30 to 40 % higher speed as compared to conventional combers .

SLIVER BREAKS AND ROLLER LAPPING

2 PER Comber Hour

TABLE - 37

Comber Sliver Unevenness ( U % )

Sliver hank 0.12 to 0.16 Ne > 0.16 Ne

Rating

Good 3.5 4.0

Average 4.0 4.5

Poor 4.5 5.0

TABLE - 38

Reduction in Yarn Imperfections at Different

Levels of Noil Extraction

Comber Noil ( % ) Reduction in *

Yarn Imperfections ( % )

Sitra Norms For Spin. 12 70 - 75

15 75 - 80

20 80 - 85

* In comparisation with carded yarn

PAGE No - 24 V DRAWING

TABLE - 39

Draw Frame Sliver C.V. %

Rating Wrapping Length ( m )

0.5 1.0 5.0

Good 2.0 1.8 1.3

Average 2.5 2.5 1.5

Poor 3.0 2.8 1.8

Note : Sliver CV % norms for Drawframes fitted with Autolevels are given in Table 115 in the

section on Norms for EOUs .

TABLE - 40

Draw Frame Sliver Unevenness ( U % )

Finisher Passage

Sliver Hank

Rating 0.12 to 0.16 Ne > 0.16 Ne

Good 2.5 3.0

Average 3.0 3.5

Poor 3.5 4.0

* The Values given in table are for combed finisher drawing sliver. For carded finisher

drawing sliver, the unevenness values will be higher by 1 U% .

TABLE - 41

Diameter of Trumpet Hole ( in mm )

Hank of Sliver Carded Counts

First passage Second Passage

0.25 and above 3.0 2.5

0.18 - 0.24 3.0 2.5

0.15 - 0.17 3.5 3.0

0.12 - 0.14 3.5 3.5

Note : For combed counts the diameter will be less by 0.5 mm .

TABLE - 42

End Breaks in Drawing

( Per 10 Delivery Hours )

Type of Drawing First Passage Second passage

Semi - High Speed 12 6


High Speed 20 10


Recommended Settings in Draw Frames Based on

AFIS Length Data

Draw Frame Roller Setting Allowance

Passage ( nip to nip in mm )

Front Back

Breaker 5 % span length 5 % length + 4 mm

Finisher 5 % length + 2 mm 5 % length + 6 mm

- Roller Setting = 5 % AFIS length ( mm ) + Roller Setting allowance

- These setting are applicable mainly to carded counts containing hooks In the material

presented to drawing . For combed counts , the same setting may be maintained at

breaker as well as finisher .

- While deciding optimum setting for draw frames CV of 0.5 m wrapping may be taken as

the criterion .

TABLE - 44

Break Draft in High Speed Draw Frame

( Carded Counts )

Draw Frame Passage Break Draft

First Passage 1.7

Second Passage 1.3

Note : For combed counts , break draft will be 1.3 for the both passage .


PAGE No - 26 VI FLY FRAMES

TABLE - 45

Roving Unevenness ( U % )

Roving Hank 0.12 to 0.16 Ne > 0.16 Ne

Rating

Good 3.5 4.0

Average 4.0 4.5

Poor 4.5 5.0

* The values given in the Table are for combed roving . For carded roving , the unevenness

values will be higher by 0.5 U %

Roving Variation CV % * ( 5 m Length )

Good 1.5

Average 2.0

Poor 3.0

* For the rovings produced from Autolevelled slivers , the roving Variation ( 5 m - CV % )

will be lower by 0.5 % ( absolute value ).

End Breaks in Fly Frames ( Per 100 Spindle hours )

20s to 39s 4.0

40s to 59s 3.0

60s and above 2.0

Variation in Empty Roving Bobbin Diameter

1.0 % maximum permissible

Roller Setting in Fly Frame Based on 2.5 % Span Length

Setting at the back zone of the drafting system in the flyframe lie within 2. 5% span length

+ 13 to 15 mm . Break draft has to be maintained in the range of 1.08 to 1.30 .

TABLE - 46

Size of the Condensing Guides in Fly Frame

Hank of sliver 0.09 to 0.121 to 0.141 to 0.171 to

( Ne ) 0.120 0.140 0.170 0.200

Sitra Norms For Spin. Inlet Condenser 18 *x 6** 15 x 3 12 x 2.5 8 x 2

( mm ) OR 16 x 4

Middle Condenser 14***or 1 11 or 9 9 or 6 9 or 6

( mm )

* - Width of delivery side of the Inlet Condenser

** - Height of delivery side of the Inlet Condenser

*** - Width of delivery side of the Middle Condenser

PAGE No - 27

TABLE - 47

Size of Floating Condenser & Spacers in Fly Frame

Hank of 0.090 - 0.120 0.121 - 0.140 0.141 - 0.170 0.171 - 0.200

Sliver

Hank of 0.5 1.1 1.7 0.6 1.1 1.7 0.7 1.3 1.7 1.0 1.7

Roving to to to to to to to to to to to

1.0 1.6 2.5 1.0 1.6 2.5 1.2 1.6 3.0 1.6 3.0

* Size of 11 9 7.5 11 9 7.5 9 7.5 6.0 6 6

Floating to to to to to to to to to to to

Condenser (mm) 18 16 14 16 14 11 14 11 9 9 7.5

Size of 6 5.5 5 6 5.5 5 5.5 5.5 5 5 5

Spacer (mm) to to to to to to to to to to to

9 8 7 9 8 7 8 8 7 7 7

* - Width

Fly Frame

Creel Tension Draft

1.01 to 1.03 to maintain creel breaks within acceptable limits .

TABLE - 48

Optimum Levels of Pneumafil Suction

Pressure in Fly Frame

Position of the Frame Suction Pressure* (cm of water)

Gear End 2

Middle End 4

Fan End 8

* Values are applicable to 120 splindle frames .

TABLE - 49

Stretch in Roving

Machine Type Stretch ( % )

1. High Speed Fourth Generation

Machines.

( Spindle speed > 1200 rpm

Sitra Norms For Spin. and lift 14 " and above ) 0.5 - 0.6

2. Third Generation Machines

( Spindle speed 1000 -1200 rpm

and lift 12 " ) 0.8

3. Second Generation Machines

( Spindle speed < 1000 rpm

and lift 10 " & 12 " ) 1.0 - 1.2

PAGE No - 28

VII YARN QUALITY

TABLE - 50

Yarn CSP for Warp Counts

Counts Good Average Poor

Carded 20s 2250 2050 1850

30s 2300 2100 1900

40s 2400 2200 2000

60s 2500 2200 2000

80s 2300 2100 1900

100s 2300 2100 1900

Combed 40s 2600 2500 2300

60s 2800 2600 2300

80s & 100s 2600 2400 2200

TABLE - 51

Yarn Unevenness ( U% )

Counts Good Average Poor

Carded 20s 12.0 13.5 15.0

30s 12.5 14.0 15.5

40s 14.5 16.0 17.5

60s 15.0 16.5 18.0

80s 16.0 17.5 19.0

Combed 30s 11.0 12.0 13.0

40s 12.0 13.0 14.0

60s 12.5 13.5 14.5

80s 13.0 14.0 15.0

100s 13.5 14.5 15.5

Table - 52

Yarn Imperfections / Km

Count Thin places Thick Places Neps

Good Average Poor Good Average Poor Good Average Poor

Carded

20s 50 150 200 250 500 600 150 450 550

30s - 40s 75 200 375 400 700 950 550 800 1200

60s 150 300 500 600 1000 1200 600 1200 1800

80s 250 500 600 600 1000 1200 600 1200 1400

Sitra Norms For Spin. 100s 250 525 750 600 1000 1200 700 1250 2000

Combed

30s 5 10 20 60 150 250 100 200 300

40s 10 20 30 60 100 200 100 150 300

60s 20 40 80 150 200 400 150 200 500

80s 70 100 200 250 500 800 200 400 600

100s 100 150 300 300 500 800 200 500 800

PAGE No - 29

Relation between Imperfections and count spun from a given cotton .

Imp / Km = Q x Ne2

Where Q is measure of the fibre quality influencing yarn imperfections .

Q = K1 + K2 X f + K3 X I FC + K4 X L + K5 X N

Where f = Mic. Value

IFC = % of Immature Fibre Content

L = 50 % span Length ( mm )

N = Neps / g in drawing sliver

( Measured by AFIS - N Instument ) and

K1 , K2 , K3 , K4 , K5 are constants .

Suppose , if 20s and 30s yarns are produced from a given cotton and imperfections in 20s

are 40 / km, then imperfections in 30s yarn will be :

40 x 302

202

= 90 / km

TABLE - 53

Yarn Classimat Faults / 100 km .

Count Short Thick Faults Long Thick Faults Long Thin Faults

A B C D E F G H I

Carded

15s - 30s 750 55 8 2 1 4 1 125 5

31s - 50s 2330 175 20 3 1 6 1 180 1

51s - 80s 6300 300 30 6 4 12 4 740 16

Combed

15s - 30s 240 30 6 1 1 3 1 20 2

31s - 50s 280 35 7 1 1 2 1 30 2

51s - 70s 480 70 15 2 1 3 1 90 1

71s - 90s 1550 150 40 7 2 9 1 200 2

91s % above 1950 170 45 10 6 20 4 420 10

TABLE - 54

Count And Strength C.V. ( % )

Rating

Sitra Norms For Spin. Property Count Good Average Poor

Count C.V % Below 40s 2.0 2.5 3.0

40s & above 2.5 3.0 3.5

Strength C.V % Below 40s 3.5 5.0 6.0

40s & above 5.0 6.0 7.0

Note : C.V. values are calculated based on 200 readings spread over a periodo to one week

taking two non - consecutive leas per bobbin .

PAGE No - 30

TABLE - 55

Yarn Apperance Grades

Count Good Average Poor

20s to 100s carded C + C D

30s & 40s combed B C C

60s to 100s combed B + C + D

TABLE - 56

Warps per Cm. For Grading Yarns

Count Warps per cm

1s to 12s 8

12s to 24s 9

24s to 36s 10

36s to 50s 13

50s to 75s 15

75s to 135s 19

RKM VALUE

" RKM " stands for " Reisskilometer " in German and " Resistance Kilometrique in French .

RKM means the Kilometers of yarn for break : that length which the yarn can support at breaking

point .

RKM Value = Single yarn strength ( g ) = CSP

Tex number of yarn 150

TABLE - 57

Fibre Quality Required to Spin Yarns with 3 Different

Levels of RKM Under Good Working Conditions

( Fibre Properties Measured by HVI Test System Using ICC Mode )

( Coarser Fibres )

Count RKM Value 50 % Span Fibre Micronaire

of Yarn Length Strength Value

( g / tex ) ( mm ) ( g / tex ) ( g / inch )

( I ) ( s ) ( f )

20s 12.0 12.0 12.7 4.4

13.5 12.3 16.4 4.4

15.0 13.5 19.2 4.4

24s 13.0 12.7 15.6 4.4

14.0 12.5 18.7 4.4

15.0 14.5 18.9 4.4

Sitra Norms For Spin. 26s 13.0 13.0 15.3 4.3

14.5 12.8 19.9 4.3

16.0 15.0 21.2 4.3

30s 13.0 13.5 14.9 4.1

14.5 13.5 19.0 4.1

16.0 15.2 20.9 4.1

36s 13.0 13.5 15.4 3.9

14.5 14.0 18.8 3.9

16.0 15.5 20.9 3.9

PAGE No - 31

TABLE - 57 ( Contd. )




( Coarser Fibres )




( I ) ( s ) ( f )

40s 13.0 14.0 15.3 3.8

14.5 14.2 19.0 3.8

16.0 15.4 21.4 3.8

44s 13.0 14.0 16.2 3.8

14.5 14.5 19.5 3.8

16.0 16.5 20.9 3.8

50s 13.0 14.3 17.2 3.8

14.5 15.0 20.2 3.8

16.0 17.1 21.5 3.8

55s 13.5 15.3 18.4 3.8

15.0 15.5 22.1 3.8

16.5 17.4 23.6 3.8

60s 14.0 15.3 20.8 3.8

15.5 16.3 23.6 3.8

17.0 17.5 26.1 3.8

70s 14.0 15.5 22.4 3.0

15.5 17.0 24.4 3.7

17.0 17.5 27.9 3.7

80s 14.0 16.5 22.7 3.6

15.5 18.0 24.6 3.6

17.0 19.0 27.3 3.6

TABLE - 58




( Finer Fibres )




( I ) ( s ) ( f )

20s 12.0 10.5 12.8 3.9

13.5 11.0 16.3 3.9

15.0 13.0 17.7 3.9

24s 13.0 11.0 15.5 3.8

14.0 12.0 16.8 3.8

15.0 14.0 16.9 3.8

Sitra Norms For Spin. 26s 13.0 11.5 14.8 3.7

14.5 12.4 17.7 3.7

16.0 14.5 18.8 3.7

30s 13.0 12.0 14.3 3.5

14.5 12.8 17.1 3.5

16.0 15.0 18.1 3.5

36s 13.0 12.8 14.3 3.4

14.5 13.0 17.6 3.4

16.0 15.5 18.2 3.4

PAGE No - 32

TABLE - 58 ( Contd . )




( Finer Fibres )




( I ) ( s ) ( f )

40s 13.0 13.0 14.4 3.3

14.5 14.0 16.7 3.3

16.0 16.0 17.9 3.3

44s 13.0 13.5 14.6 3.3

14.5 14.0 17.5 3.3

16.0 16.0 18.7 3.3

50s 13.0 14.0 15.2 3.3

14.5 14.3 18.4 3.3

16.0 16.5 19.4 3.3

55s 13.5 14.5 16.8 3.3

15.0 14.5 20.5 3.3

16.5 16.5 21.6 3.3

60s 14.0 15.0 17.9 3.2

15.5 15.0 21.6 3.2

17.0 17.0 22.6 3.2

70s 14.0 15.5 19.3 3.2

15.5 16.0 22.4 3.2

17.0 17.5 24.1 3.2

80s 14.0 16.0 19.5 3.0

15.5 16.5 22.4 3.0

17.0 17.8 24.3 3.0

90s 14.0 16.0 22.3 3.1

15.5 16.5 25.4 3.1

17.0 18.5 26.3 3.1

100s 14.0 17.0 23.8 3.2

15.5 17.2 27.4 3.2

17.0 19.5 27.9 3.2

TABLE - 59

Yarn Hairiness Values

( Hair / Metre with Hair Length 3 mm and Above )

Yarn Type Count Good Average Poor

Carded 20s 15 35 50

30s 15 30 40

40s 15 35 45

Sitra Norms For Spin. Combed 30s 8 20 50

40s 8 25 40

60s 10 25 40

80s 15 25 40

100s 10 20 30

PAGE No - 33

TABLE - 60

Number of Test and precision for various

Yarn Quality Characteristics

Test No. of 95%

Tests C.V% Confidence

Yarn Count 25 2.5 .+-1

Yarn Imperfections * 5 25.0 .+-22%

Yarn Unevenness U% 5 4.0 -3.6

Single End Break 100 8.0 .+-1.6%

Skein Break 25 6.0 -2.4

Ply Yarn Twist # 50 4.0 .+-1.1

Single Yarn Twists 50 6.0 .+-1.7

Here : * for 2000 m length # for 25 cm length

VIII. RING SPINNING

TABLE - 61

Optimum Level of pneumafil suction Pressure in Spinning

Position of Suction Pressure

the Frame ( cm. Of water )

Gear End 6

Middle 8

Fan End 12

* values applicable to both short length and long length Ring Frames

TABLE - 62

Back Zone Setting in Ring Frame

Count Roller Settings (mm)

Upto 20s 56

21s to 60s 60

61s & above 65

Note : Water back zone setting ought to be accompanied with a lower break draft

I.e. 1.1 - 1.2

TABLE - 63

Traveller Clearer Setting in Ring Frame

Count Settings (mm)

above 40s 1.6

Sitra Norms For Spin. 21s to 40s 2.0

20s & below 2.4

PAGE No - 34

TABLE - 64

Spacer for Different Counts in Ring Frame

Count Appron Spacer (mm)

upto 20s 4.0

21s to 40s 3.4

41s to 80s 3.0

81s and above 2.25

TABLE - 65

Humidity Correction for Yarn Count at 800 F

Poyester / Poyester /

RH% Cotton Viscose Viscose Cotton

( 48/52) ( 67/33)

40 0.973 0.966 0.9800 0.9904

45 0.978 0.970 0.9839 0.9923

50 0.985 0.975 0.9873 0.9939

55 0.991 0.980 0.9912 0.9960

60 0.997 0.988 0.9956 0.9979

65 1.000 1.000 1.0000 1.0000

70 1.007 1.010 1.0059 1.0019

75 1.013 1.018 1.0122 1.0051

80 1.020 1.028 1.0199 1.0084

85 1.033 1.045 1.0307 1.0135

90 1.051 1.090 1.0546 1.0183

Lea Strength Corrected to Nominal Count

S2= C1S1 - 18 ( C2-C1)

C2

Where S2 = Observed Les strength (lb)

S1 = Corrected strength to Nominal count (lb)

C1 = Observed count ( Ne)

C2 = Nominal count (Ne)


PAGE No - 35

IX DOUBLING

TABLE - 66

Doubled Yarn CSP

Count Good Average Poor

(Ne)

Carded

2/20s 2400 2250 2100

2/30s 2700 2550 2400

2/40s 2800 2650 2500

2/60s 3000 2850 2700

2/80s 3000 2850 2700

Combed

2/30s 3000 2850 2700

2/40s 3200 3050 2900

2/60s 3300 3150 3000

2/80s 3400 3250 3100

2/100s 3500 3350 3200

TABLE - 67

Doubled Yarn CSP

Property Good Average Poor

Count CV%

Below 2/40s 0.8 1.2 1.8

2/40s and above 0.9 1.1 2.0

Strength CV% 2.5 4.5 6.0

Below 2/40s 3.5 5.0 6.5

2/40s and above

TABLE - 68

Yarn Unevenness (U%) and Imperfections

Imperfections / Km

Count Thin Thick

(Ne) U% Places Places Neps Total

Carded

2/20s 10.5 0 56 41 97

2/30s 11.0 6 107 55 168

2/40s 11.5 7 116 121 244

2/60s 14.0 50 543 857 1450

2/80s 14.5 68 594 875 1537

Sitra Norms For Spin. 2/100a 15.0 61 661 976 1698

Combed

2/40s 9.0 0 23 74 97

2/60s 9.5 1 5 10 16

2/80s 10.0 5 66 112 183

2/100s 10.5 4 32 75 111

PAGE No - 36

TABLE - 69

Yarn Qual;ity Improvement Due to Doubling

S Quality single Yarn Percent

No Parameters Count (Ne) Improvement

1 CSP 20s - 40s 10

40s - 60s 15

60s & Finer 25

and

Man - made fibre

& blended yarns 25

2 Lea All Counts 0.5*

Count CV%

3 Lea strength All Counts 1.0*

CV%

4 Single Yarn All Counts 20

Strength CV

5 Twist CV All Counts 20 - 40

6 Hairiness All Counts 60 - 80

7 Total Below 60s 90

Imperfections 60s & Finer

8 Classimat All Counts 70 - 90

Objectionable

faults

* Absolute Values

1. % improvement is with respect to the level of yarn quality at single yarn stage.

2. The strength improvement depends upon the direction and amount of doubling twist

For normal doubled yarns .

D / S = Doubled Yarn TPI

Single Yarn TPI

D / S will be around 0.7 to 0.75 and the direction of twist will be S / Z ( S - the direction of

the doubling twist & Z - the direction of the single yarn twist ) . In case of Z / Z doubled yarns , the

CSP will be lower by 20 to 30 % ( 20 % at a D/S ratio of 0.7 and 30% at a D/S ratio of 1.1 ) .

TABLE - 70

Importance Performance Parameters for Two - For - One Twister

Parameters Good Average Poor

Breaks / 1000 Spindle Hours

10 15 20

Twist Variation ( CV% ) *

Cotton Yarn 3 4 5

Sitra Norms For Spin. * Based on 30 random samoles collected from all machines .

TABLE - 71

End Breaks at Cheese Winding

Good Average Poor

Breaks / Lakh. Metre 2 5 10

PAGE No - 37

X GENERAL

Tolerance Limits for Pinion Changes

C ± C A

Where ,

C - Sliver hank of yarn count

A - The number of teeth on the change pinion .

When we choose n = 6 A x CV

100

Where n = Number of readings taken for measurement of sliver hank / yarn count .

CV = CV of Drawing Sliver Hank

TABLE - 72

Relative Humidity And Temperature For Different Departments *

Departments R.H. % Temperature0C

0F

Mixing 60 - 65 27 - 35 80 - 95

Blow Room

Card Room 50 -55 27 - 35 80 - 95

Preparatory

Ring Spinning 50 - 60 27 - 35 80 - 95

Winding 60 - 65 27 - 32 80 - 90

* About 5 % higher (than Cotton Spinning) RH % has to be maintained while spinning blended yarns.

TABLE - 73

Shore Hardness of Top Roller Cots

Machine Shore Hardness

Comber Draw box Top Rollers 700 - 80

0

Comber Detaching Rollers 600 - 65

0

Darw Frame top rollers 800 - 90

0

Fly Frame top rollers 800

Ring Frame top rollers 600 - 70

0

TABLE - 74

Sitra Norms For Spin. Top Roller Pressure ( Kg ) - Drawframe

Type of Type of Front Middle Back

Drawframe Drafting

System

Conventional

Drawframe 3/5 80 80 80

3/3 50 - 60 50 - 60 50 - 60

Autoleveller

Drawframe 3/3 64 64 64

5/4 30 40 50

PAGE No - 38

TABLE - 75

Top Roller Pressure ( Kg ) - Fly Frame

Count Front Appron Roller 3rd & 4th

Coarse & Medium Count 25 12 15

Fine Count 20 12 14

Note : In modern 4 over 4 Drafting systems where the apron zone is shifted to middle zone , the

front top roller pressure is 18 Kg for coarse and medium counts and 16 Kg for fine counts .

TABLE - 76

Top Roller Pressure Ring Frame

Position Pressure ( Kg )

Front Line 16 - 18.

Middle Line 10 - 12.

Back Line 12 - 14.

TABLE - 77

Eccentricity of Bottom and Top Rollers

Good 0.050 mm

Average 0.075 mm

Poor 0.1 mm

TABLE - 78

Yarn Waste, Sweep Waste, And Invisible Loss ( % )

Type of Waste Good Average Poor

Yarn Waste

- Conventional cone

Winding or Doubler 0.1 0.2 0.3

Winding or Ring

Doubling or TFO

- Auto Winding 0.5 0.8 1.0

Sweep Waste 1.0 1.5 2.0

Sitra Norms For Spin. Gutter Waste /

Filter Waste 1.0 1.5 2.0

Invisible Loss 0.5 1.0 1.5

PAGE No - 39

TABLE - 79

Usable Waste % for Good Working

Type of Waste Lapfed Chutefed

System System

Lap bit and card web 0.7 0.2

Sliver in drawing and fly frames 0.5 0.5

Waste at comber preparatory and comber 1.0 1.0

Roving ends 0.3 0.3

Pneumafil and bonda waste 2.5 2.5

Total 5.0 4.5

Yarn Realisation ( YR % )

YR % = 97.5 - t - WK - Wh for carded counts

= ( 100 - t - WK ) [ 1 - C / 100 ] - Wh - 2.5

For combed counts

Where

t = % trash in mixing

WK = % card waste

C = % Comber noil

Wh = % Hard waste

TABLE - 80

Shade Variation in Dyed Fabrics

Types of Fabric *

Cotton 1.0

Man - Made - Fibre 0.5

* is a measure of the shade variation which is estimated using Spectrophotometer .

TABLE - 81

Fibre Properties Required to Produce Cotton Fabrics

With a E Value of 1.0

Fibre Properties

Combination Range in Mic . IFC (%)**

Sitra Norms For Spin. Value*

1 0.50 30.0

2 0.65 27.5

3 0.80 25.0

* Range in Mic. Value of the cottons used in the mixing.

** Average Immarature Fibre Content in th emixing.

- Any on of the three combination of the fibre properties as shown in Table 81 will be suitable

to produce cotton fabrics with E value of 1.0 .

PAGE No - 40

XI CONVENTIONAL CONE WINDING AND REELING

TABLE - 82

Slub Catcher Setting at Cone Winding

Count Setting in Count Setting in

( Ne ) 1/1000" ( mm ) ( Ne ) 1/1000" ( mm )

20s 17 (0.43) 60s C 7 (0.18)

30s 14 (0.35) 80s C 9 (0.21)

40s 12 (0.30) 80s C 6 (0.16)

60s 10 (0.25) 100s C 5.5 (0.14)

Setting Guage = 2 times the yarn diameter for carded counts and 1.5 times the

yarn diameter for combed counts .

Yarn diameter in mm = 0.95

count

Tension Weight in Winding

Tension weight in g = 8 to 10 % of Single Yarn Strength in g .

TABLE - 83

Ends Breaks per One Lakh Meters for Good Working

Count During During

( Ne ) Winding Rewinding

20s and below 16 8

21s to 40s 10 5

Above 40s 8 4

* Rewinding test is to be carried out at an open slub catcher setting.

TABLE - 84

Number of Clearer Cuts in Auto Winders

( per one lakh meter)

Rating Good Average Poor

Clearer Cut 35 60 90


TABLE - 85

Rewinding Breaks for

Electronocally Cleared & Spliced Yarns

( per one lakh meter)

Good Average Poor

2 4 7

* During electronic cleaning , settinf for rewinding are same as that used during winding .


Variation in the Number of Threads in Hank and

weight of Bundle,Bale & Cone

Parameter Allowable Variation

Threads in Haank 15 threads

Bundle weight 0.5%

Bale weight 0.5Kg

Cone weight 50Kg

Defective Cones < 1%

XII ROTOR SPINNING

Mixing for Oped - End Yarns

TABLE - 87

Mixing Details and Fibre Quality Characteristics

for Open-End Spinning

( fibre properties measured by conventional Testing Instrument )

.2.5% .0.5% Micro- Stelometer Matu-

Count Mixing Span Span naire Strength rity Trash

Components length length Value (3 mm guage) Coeff- %

mm mm (ug/inch) in g/tex icient

6s Yelllow Picking 50% 21 9.5 4 15 0.8 7.5

Comber Noil 25%

Flat Strip 15%

Hard Waste 10%

10s Virgin Cotton 65% 22 10 5 15.5 0.8 6

Flat Strip 25%

Comber Noil 10%

14s Virgin Cotton 100% 23.5 10.5 4 17 0.8 6

20s Virgin Cotton 100% 24 11.5 3.8 20 0.8 5

Export quality

7s Virgin Cotton 100% 24.5 12 4.2 19 0.8 4.5

14s Virgin Cotton 100% 25.5 12.5 4.2 20 0.8 4

TABLE - 88

Sitra Norms For Spin. Trash Content (%) in Card sliver Meant for Rotor Spinning

Good Average Poor

0.1 0.3 0.5

TABLE - 88

End Break in Rotor Spinning / 100 Rotor Hours.

Conut ( Ne) Good Average Poor

6s 7 10 20

10s 7 10 20

16s 3 8 15

20s 3 8 15

book page 75 & 76

PAGE No - 42

TABLE - 90

CSP For OE Yarns

Mixing Count (Ne) CSP

Virgin Cotton 6s 1900

10s 1800

16s 1750

20s 1700

Waste Cotton 6s 1650

10s 1600

16s 1550

20s 1500

TABLE - 91

Unevenness & Imperfections in OE Yarn

Mixing Count U% Imperfections / Km Total

(Ne) Thin Thick Neps

Virgin Cotton 6s 12 0 25 1 26

10s 10 2 30 20 52

16s 10 5 40 30 75

20s 10 10 50 50 11

Waste Cotton 6s 12 20 70 10 100

10s 12 35 120 50 205

16s 12 100 150 75 325

20s 15 150 200 120 470

TABLE - 92

Count & strength Variation in OE Yarn

Count C.V of C.V of

Mixing (Ne) Count(%) Strength (%)

Virgin Cotton 6s to 20s 2 5.5

Waste Cotton 6s to 20s 2.5 6

TABLE - 93

Recommended Rotor Diameter

Count Rotor Diameter

Sitra Norms For Spin. (Ne) (mm)

1s to 3.5s 66

3.6s to 9s 54

10s to 20s 45

TABLE - 94

Elongation & Hariness of Rotor Yarns

Count Elongation Hairiness

(Ne) (%) Index *

6s 7 7

10s 7 6

16s 6.5 5

20s 6 4.5

Hairiness Index is measured using Uster 3 Instrument

book page 77 & 78

PAGE No - 43 XII MAN - MADE FIBRES AND BLENDS

Typical Properties of Man - Made Fibres

Property Viscose Polynosic Lyocell Polyster Acylic

Tensile strength 2.0 - 2.5 3.0 - 3.5 4.8 - 5 4.5 - 6.5 3.5 - 4

(g/d)

breaking Elong- 16 - 22 .9 - 14 14 - 16 30 - 50 30 - 40

ation (%)

Specific Gravity 1.5 1.5 1.5 1.38 1.17

Moisture Regain % .12 - 44 12 - 14 .12 - 14 0.4 - 0.5 1.6

TABLE - 96

Quality Attributes of P/C Yarns

Yarn Quality 30s 40s 60s 80s

Lea CSP 3040 3100 2600 2750

Count CV (%) 1.9 2.0 2.4 2.5

Strength CV (%) 5.0 5.4 6.8 7.0

RKM (g/tex) 19.2 20.3 19.5 20.9

RKM CV (%) 10.4 10.6 13.8 14.1

Yarn Unevenness (U%) 11.7 13.2 16.3 15.3

Total imperfections / Km 235 960 2600 1475

Elongation (%) 8.8 8.3 9.1 9.0

Note : The twist factor lies between 3 and 3.3

TABLE - 97

Quality Attributes ofP/V Yarns

Yarn Quality 30s 40s 60s

Lea CSP 4122 4212 3037

Count CV (%) 2 3.0 2

Strength CV (%) 5.0 4 6

RKM (g/tex) 25 23 20

RKM CV (%) 9 12 12

Sitra Norms For Spin. Yarn Unevenness (U%) 11 12 14

Total imperfections / Km 136 152 510

Elongation (%) 11 11 10

Note: - (1) The twist multiplier for the above yarn spun from 38 mm fibre ranges from 3.2 to 3.5

(2) For Yarns spun from 44 mm & 51 mm fibres, the teist multiplier will be in the rsnge of

3.0 to 3.3 & the CSP will be higher by about 200 units.


Properties of Ring & Rotor Spun Yarns Made Out of Lyocells fibres

Ring Yarn Rotor Yarn

Yarn Quality 16S Ne 30s Ne 50s Ne 12s Ne 30s Ne

Tenacity (CN/tex) 30 27.5 23 20 19.5

Elongation (%) 12.2 9.4 8.3 10 8.5

Unevenness (U%) 8.1 11.7 12.5 11.4 13.6

Neps/Km 8 14 49 8 30

TABLE - 99

Hairiness Values ( Hairs/m. with Hair length Greater than 3 mm)

Yarn Type Count Good Average Poor

(Ne)

Viscose 31s & 40s 10 15 25

Polyster/Cotton 30s (67/33) 10 20 25

50s (67/33) 4 8 12

Polyster/Viscose 60s (48/52) 5 12 17

TABLE - 100

Norms for OE Man - Made Fibres and blended Yarns

Yarn 100% 100% Polyster/ Polyster/

Quality Polyster Viscose Viscose Cotton

(48% / 52%) ( 67% / 33%)

Count 15s 20s 15s 20s 15s 20s 15s 20s

Rkm (g/tex) 19 24 9.5 9 10.5 14 17 22

Unevenness (U%) 11 11.5 11 11 10.5 11.5 11 11.5

Impefection / Km

Thin Places 4 11 8 13 6 14 8 21

Thick Places 24 32 29 34 24 31 26 44

Neps 36 59 34 62 41 59 41 69

Total Imp. 64 102 71 109 71 104 75 134

Process Parameters to be adopted During Processing of Blends

BLOW ROOM

Sequency of Machinery

Hopper feeder

Kirschner beater 1 or 3 Bladed beater

Hopper feeder with reserve box

Kirschner beater II

Sitra Norms For Spin. Lap end

CARDING

TABLE - 101

Speed in Cards

Element Unit Type of Card

SHP HP VHP

Licker-in rpm 400-500 500-900 900-1100

Cylinder rpm 200-250 250-350 350-450

Doffer rpm 10-12 20-25 40-45

Flats inch/min 3 5 6

The amount of waste extracted during carding (Strippings , dropping,lap bits,sliver etc)

would be around 1 to 1.5 %


Setting in SHP Cards

Setting Points Setting ( mm )

Feed plate to licker-in 0.500

Licker-in to cylinder 0.175

Cylinder to Flats 0.375 - 0.500

Cylinder to doffer 0.100 - 0.125

Doffer to doffer comb 0.375 - 0.425

Back plate to cylinder - Top 0.550

- Bottom 0.850

Front plate to cylinder - Top 0.550

- Bottom 0.850

Licker in to undercasing 0.625 - 0.850

( at nose )

Cylinder to undercasing 0.85 - 1.40 - 2.55

Note : The above setting are applicable to fibres of 38 mm cut length. When fibres longer than

38 mm are used , the feed plate to Lickerin setting must be widened to 0.675 - 0.75 mm .

TABLE - 103

Setting in HP Cards

Setting Point Setting ( in mm )

Feed roller to feed plate 0.125

Feed plate to licker - in 0.750

Lickner - in to mote knife I 0.750

Lickner - in to mote knife II 1.000

Lickner - in to combing segment I 0.750

Lickner - in to combing segment II 1.000

Lickner - in to Lickner - in undergrid 0.550

Licker - in undergrid to Cylinder 0.550

Lickner - in to Cylinder 0.250

Cylinder to back plate - Top 0.550

- Bottom 0.650

Cylinder to carding plate - Top 0.800

- Bottom 0.600

Cylinder to Cylinder - under - grid 0.55,1.3,1.3,2.2,3.0

Cylinder to flats 0.5,0.5,0.4,0.4

Cylinder to front plate - Top 0.500

- Bottom 0.350

Cylinder to front bottom plate 0.450

Cylinder to Doffer 0.100

Take off roller to grooved roller 0.125

Sitra Norms For Spin. Grooved roller to Crush Roller 0.250

Gap between crush rollers 0.55

Genearl Precautions

1. The weighting on the feed rollers must be greater than that for cotton by 50 %

2. The Licker- in droppings and flat strips should not be reused .

Precautions for Processing Tinted Man - Made Fibres :

1. Undercasing have to be taken out and washed with soap water once in a week. Before refitting

Graphite powder is to be applied on the surface of the undercasing.

2. Both the surfaces of cylinder and doffer are to be stripped once in a week with petrol or carbon

Tetrachloride.

3. As more humid condition is preferred in the carding department, lubrication of flat chain should

be done once in a week .

PAGE No - 46 Preventive Measures to Avoid Coiler Choking :

1 Chromium plated steel tubes are to be used for coiler .

2 Humidity of the department should be maintained at 55 - 60 % R.H.

3 The surface of the coiler tubes should be smooth and clean.

4 Cards cans with springs should be used .

5 Higher calender roller loading is to be employed .

DRAWING

TABLE - 104

Process Parameters in Drawframes

Parameters High Speed High Speed

Draw Frame Draw Frame

Drafting System 3 / 5 4 / 5

Top roller Loading 80 Kg per top 80 Kg per top

roller roller

Nip to Nip Setting:

38 mm Fibre 42 - 48 42 - 48

51 mm Fibre 58 - 62 58 - 62

Break draft 1.73 in I st 1.73 in I st

passage and passage and

1.3 to 1.5 1.3 to 1.5

in subsequent in subsequent

passages passages

Tumpet size ( mm ) 2.5 - 3.5 2.5 - 3.5

( Depending on Hank )

Front roller Delivery * 250 - 300 250 - 300

( m / min )

The web tension draft should be around 1.0 for viscose and 0.98 for P / C and P / V blends.

Process waste in drawing would be around 0.3 - 0.5 %

* For drawframes fitted with Autolevellers, the recommended delivery speed is about 350 m / min .

TABLE - 105

Drawframe Sliver Unevenness ( U% )

Material U %

Polyester 2.0

Viscose 2.5

PV Blend 67/33 2.0

48/52 2.0

PC Blend 67/33 3.0

48/52 3.0

Note : Unevenness values for obtained from autoleveller drawframes will be less by 0.5 U % .

Fly Frame

Sitra Norms For Spin. TABLE - 106

Speeds, Setting and Twist in Fly Frame Processing

Drafting System Spring Pneumatic

Loading (4/4) Loading (3/3)

Roller Setting - (mm)

Front to Back :

- 38 mm fibre 44 - 50 - 60 44 - 50

- 51 mm fibre 59 - 54 - 74 59 - 70

Total Draft 10 - 15 10 - 15

Break Draft 1.08 - 1.30 1.08 - 1.30

Middle zone draft 1.04 -

Spacer size ( mm ) 6 - 7 6 - 8

Top Roller Loading 25/10/15/15 24/12/16

(Front to Back in Kg)

Flyer speed ( rpm ) 900 to 1000 900 to 1000

Twist Multiplier

- 38 mm fibre 0.7 - 0.8 0.7 - 0.8

- 51 mm fibre 0.6 - 0.65 0.6 - 0.65

PAGE No - 47

1 In 4/4 Drafting System used in fly frame, the middle zone setting is fixed . 36 mm guage is

generally used for processing 38 mm fibres & 50 mm guage for fibres of 51 mm and longer. While

using 36 mm guage, the middle zone setting is 50 mm & while using 50 mm guage, it is 54 mm.

2 Process waste in fly frames ( sliver, Roving ends,etc ) would be around 0.5 % .

3 For processing man - made fibres, it is better to fit the flyer top with false twist attachment ( made

out of rubber or plastic with 6 - 8 grooves on the inside ) . These attachments impart additional

twist to rove between the flyer top and front drafting rollers and make it more compact.

TABLE - 107

Roving Unevevnness ( U % )

Hank Polyester Viscose P/V Blends P/C Blends

( 100 % ) ( 100 % ) 67/33 48/52 67/33 48/52

1.0 - 2.0 3.0 - 3.25 3.0 3.0 3.5 3.5 4.0

2.0 - 3.0 3.5 - 4.0 3.5 3.5 4.0 4.0 5.0

RING FRAMES

TABLE - 108

Process Parameters in Ring Frames

Parameters Types of Drafting

Spring Pneumatic

Loading(4/4) Loading(3/3)

Roller setting (mm)

Front & Back :

.- 38 mm Fibre 44-56 44-65

.- 51 mm Fibre 56-70 58-70

Total draft 20-40 20-40

Break draft 1.15-1.4 1.13-1.38

Spacer (mm) Yellow / Back .18/12/16

Top Roller loading 18/10/14/14

( front to back) kg

Anti - wedge ring with spiv or clip type of travellers are most suitable for man-made fibre

procesing. The cross-section of the traveller should be half round.

Traveller for polyster blends have to be about 4 - 5 numbers heavier and those for viscose 3 - 4

numbers heavier as compaired to travellers used fro 100% cotto yarns.

It is advisable to use ballon control rings.

The presence of Titanium Dioxide in polyster necessitates more frequent traveller changes.

Yarn twist for man - made fibre to be much lower than that for 100$ cotton. A broad guideline

for yarn twist for man-made fibres and blends is given below :

TABLE - 109

Sitra Norms For Spin. Twist Multiplier for Yarn from Man - Made fibres & Blends

Material End Use T.M.

Polyester Weaving 3.2 - 3.5

Polyester Sewing Threads 3.0 - 3.3

Polyester/cotton Weaving 3.5 - 4.0

Polyester/cotton Knitting 3.0 - 3.3

Polyester/Viscose Weaving 3.0 - 3.5

Viscose Weaving 2.5 - 3.0

Viscose/ Cotton Weaving 3.6 - 4.2

Ply yarn twist,in general ,varies from 70 to 85% of single yarn twist for 51 mm fibre & 80 to 90%

of single yarn twist for 38 mm fibre. Higher twist factors may have to employed depending on the type of

warp preparation with or without sizing,fabric construction. Finish and desired feel. Doubling speed would

be about 9,000 to 10,000 rpm and normal twist direction is 'S'

The process waste in spinning (roving ends,bondas etc.) should be below 2.0%. In addition,the

amount of sweepings and fly would be around 0.2% and invisible loss below 0.5% and 1.0%. The amount

of hard waste would be about 0.5%.

Yarn realisation (%) = 97.5

PAGE No - 48 Twist Setting

To prevent snarling, steam setting is essential for polyester yarns. The recommended steam

setting conditions are given below :

Vaccume guage - 700 - 750 mm Hg

Tempersture - 95 - 1100 C

Time duration - 15 - 30 minutes

TABLE - 110

Shore Hardness on Top Roller Cots

Material Shore Hardness - ( Shore A0 )

( For Front & Back Rollers)

Polyester / Cotton 850

Polyester / Viscose & 850

Polyester

Acrylic & Viscose 900

XIV. NORMS FOR EXPORT ORIENTED SPINNING MILLS (EOUs)

The norms provided in the earlier sections are mainly for mills catering to domestic marlts.

However ,over the past few years,many export oriented spinning units have cone up all over the country

and some of thest mills are members of SITRA. Presently, all the EOUs and also mills producing export

yarn have installed state of art machinery to be able to produce yarns meeting international quality standards.

In addition to the importance given to the choce of sophisticated machinery , these mills also take adequate

care in the raw material selection as well. Generally , these mills resort to underspinning of cotton. Therefore

the norms provided in this section are for EOUs as well as for mills producing export quality yarns .

The salient features of the machinery used in these mills are indicatedbelow :

- Modern blow room line with bale pluckers and chute feed system to cards.

- Fourth generation cards fitted with long-term autolevellers.

- Modern combers with 8 end doubling and with higher intensity of combing (due to increase in the

angle of combing ).

- High speed drawframes with open loop short-term autolevellers.

- Modern high speed flyframes with improved drafting (with facilities for higher top rollers loading)

better creel design to minimise sliver stretch.

- Ringframes with better design parameters.

- Auomatic cone winders attached with electronic yarn clearers with provosion for setting the

Sitra Norms For Spin. clearing curve based on classimat faults analysis.

TABLE - 111

Mixing and Blow Room

Neps/gram

Stage Coarse Medium Fine Superfine

20s-30s 40s 50s-70s 80s & above

Mixing 60-90 90-120 100-130 130-160

Delivered

material 100-160 160-240 170-250 250-320

from Blow

Room

Note : The cleaning efficiency of modern bloe room lines is around 55 - 60 %

* Based on intrumental analysis.


Quality Characterstics of Cottons Used for Export Yarns

( HVI Measuremnts )

Count 2.5 SpanUniformity Micronaire Bundle Maturity Trash

Length Ratio Value Strength Ratio Content

( mm ) ( % ) (mg/inch) (g/tex) ( % )

20s 26-28 51 3.8 - 4.0 20.5-21.5 0.8 4.0

30s 27-29 51 3.6 - 3.8 21 - 22 0.8 4.0

40s 29-31 52 3.5 - 3.7 21-22.5 0.8 3.5

60s 31-33 52 3.3 - 3.6 25-27 0.8 3.5

80s 32-34 54 3.3 - 3.6 26-27 0.8 3.0

100s 33-35 55 3.3 - 3.6 26-28 0.9 3.0

* Tested by Shirley trash analyser.

SPINNING - PREPARATORY PROCESS

TABLE - 113

Nep Level in Card Siver and Comber Sliver

Count Coarse Medium Fine Superfine

Material 20s-30s 40s 50s-70s 80s & above

Card Sliver 30 - 45 45 - 60 60 - 75 75 -100

Comber Sliver 6 - 10 10 - 12 12 - 15 15 - 20

TABLE - 114

Unevenness ( U % )

Material Coarse & Medium Fine

Counts Counts

Card sliver 3.5 4.0

Comber Sliver 3.5 4.0

Drawframe Sliver

( Finisher )

- Carded 2.5 2.5

- Combed 2.0 2.0

Roving

- Carded 3.5 4.0

- Combed 3.0 3.5

TABLE - 115

Draw Frame Sliver CV %

Sitra Norms For Spin. Wrapping Length 1 m 0.5 m

Rating

Good 0.75 1.30

Average 1.00 1.50

Poor 1.25 1.80

TABLE - 116

Characterstics of Good Export Yarns

Characterstics 20s 30s 30s C 40s C 60s C 80s C

Count CV ( % ) 1.2 1.2 1.2 1.3 1.4 1.5

Rkm ( g / tex ) 15.0 16.0 16.5 17.0 17.0 18.0

Rkm CV ( % ) 9.0 9.0 8.5 8.5 9.0 9.5

Unevenness (U%) 95.0 10.0 9.0 10.0 11.0 12.0

Total

Imperfections / km 80.0 110.0 40.0 75.0 150.0 200.0


Process Parameters in Speed Frames in Exporting Mills

Yarn Roving TM Break Roller Setting

Count Hank Draft Back zone

( Ne ) ( Ne ) ( mm )

20s 0.9 1.3 1.1 50

30s 1.1 1.2 1.1 50

30s C 1.2 1.3 1.2 50

40s C 1.4 1.3 1.1 52

60s C 2.1 1.3 1.3 53

80s C 2.5 1.1 1.3 55

TABLE - 118

Process Parameters in Ring Frames in Exporting Mills

Count TPI Break Roller Setting

( Ne ) Draft Back zone

( mm )

20s H 17.0 1.14 60

30s H 21.0 1.14 60

30s CH 19.7 1.14 60

40s CH 22.8 1.14 60

60s C 31.0 1.14 65

80s C 35.6 1.16 65

TABLE - 119

Process Parameters in Autowinders in Exporting Mills

Count Winding Setting Clearer Setting

Speed Parameters Short Long Long

( mpm ) Thick Thick Thin

Faults Faults Faults

20s KH 1400 Dia ( % ) 250 140 -30

30s KH Len ( cm ) 2.0 30 20

30s CH 1200 Dia ( % ) 200 150 -30

Len ( cm ) 2.0 40 30

40s CH 1100 Dia ( % ) 150 140 -35

Len ( cm ) 1.5 70 60

60s C 1000 Dia ( % ) 200 150 -40

Len ( cm ) 2.0 50 40

80s C 1000 Dia ( % ) 200 160 -40

Sitra Norms For Spin. Len ( cm ) 2.0 12 25

TABLE - 120

Composition of Wax for Optimum Performance

Composition Percentage ( % )

- Paraffin Wax 90

- Coconut Oil 8 to 9

- Vegetable Tallow 1 to 2

Note : Wax pickup during winding may be maintained at 0.15 % so that the coefficient of dynamic friction

( ) of waxed yarn is maintained around 0.15 to 0.17 .

PAGE No - 51 NORMS FOR PRODUCTIVITY IN SPINNINGEXPANDED CONTENT

I MIXING AND BLOW ROOM

Production per Scutcher and Weight per Meter of lap 54

Work Assignments for Mixing Attendants, Scutcher Attendants, 132

Back Attendants and Jobers .

No. of Scutcher unit Required to Balance 1000 spindles in Ring Spinning 154.156

HOK and OHS Norms for Mixing and Blow Room ( 40s count ) 166

HOK and Work Assignments for Mixing Attendants and 169

Blow Room Tenters in EOU / High Tech mills

II CARDS

Production Rates, Sliver Hank And Doffer speeds :

- For High Production Cards 54

- For Super high Production Chute Feed Cards with Autolevellers . 55

Work Assignments for High Production Cards 132

Ancillary Labour Complement (other) for High Production Cards 132

Sliver Content Per Can 153

No. of Cards Required to balance 1000 Spindle in Ring Spinning 154.156

HOK and OHS Norms for Cards ( 40s count ) 166

HOK and Work Assignments for Cards 169

Tenters in EOU / High Tech mills

III COMBERS

Production Rates in High - Speed Combers 102

Work Assignments for High - Speed Combers Tenters 132

No. of High - Speed Combers Required to balance 1000 Spindle in Ring Spinning 157

HOK Norms for Combers ( 40s count ) 166

IV DRAW FRAMES

Production Rates, Sliver Hank , Front Roller Speeds and Machinery Efficiency :

- For High Speed Draw Frames 103

- For Super High Speed Draw Frames with Autolevellers . 105

Work Assignments for Darw Frame Tenters . 132

Sliver Content Per Can 153

No. of Finisher Deliveries Required to balance 1000 Spindle in Ring Spinning 154

HOK and OHS Norms for Drawing ( 40s count ) 166

HOK and Work Assignments for Draw Frame Tenters in EOU / High Tech mills 169

V FLY FRAMES

Production Rates, Spindle Speeds, Roving Hank, 108-109

Twist Multiplier and Machine Efficiency

Sitra Norms For Spin. Draft Used on Fly Frames 128

Work Assignment for Tenters 133

Work Assignment for Doffers 133

Ancillary Labour Complement (other) 133

Roving Content Per Bobbin 152

No. of Spindle Required to balance 1000 Spindle in Ring Spinning 154

HOK and OHS Norms for Fly Frames 166

HOK and Work Assignments for Fly Frame Tenters 169

And Doffer in EOU / High Tech mills

VI RING FRAMES

Production Rates, Spindle Speeds,

Twist Multiplier, TPI and Machine Efficiency

- For Carded Counts 111

- For Combed Counts 113

Break - up of Loss in Machine Efficiency 115

Percentage Contraction in Cotton Yarns Due to twist 116

for Various Twist Multiplier

Drafts Used on Ring Frames 129

Traveller Number to be used 130

PAGE No - 52

Work Assignment for Tenters Doffers and 133

Ancillary Labour Complement (other)

Ends Breaks Allowable for Different Work , Assignment to tenters 138

Pneumafil Waste % Expected for Various End 141

Breakage Rates And Creel Exhaust

Creel Running Time for Different Creel Bobbin Contents 148

Yarn Content Per Cop 151

Yarns to be Reccorded on Hank Indicators for Standard 158

Spindle Speed and TPI

Factors for converting Production Per Spindle to 40s Count 165

HOK and OHS Norms for Ring Frames ( 40s Count ) 166

HOK and Work Assignments for Ring Frame Tenters 170

And Doffer in EOU / High Tech mills

VII DOUBLING

Production Rates, Spindle Speeds, TPI and Machine Efficiency

- For Ring Doubling 117

- For Two - for - One Twister 118

Traveller Number to be used 131

VIII REELING

Productions and No. of Doffs per Reeler for Single Hank Plain 120

Reeling (SHPR ) , Double Hank Plain Reeling (DHPR) and

Double Hank Cross Reeling (DHCR)

No. of Reels Required to balance 1000 Spindlesin in Ring Spinning 154

IX CONE WINDING

Production Per Tenter, Work Assignments and Machine Efficiency

- For Conventional Cone Winding 122

- For Automatic Cone Winding 125

Achievable Production per Tenter in Conventional Cone 150

Winding for Different Conditions

No. of Drums Required to balance 1000 Spindlesin in Ring Spinning 154

X ROTOR SPINNING

Production Per Rotor, Rotor speed, Twist Multipliers and Machine Efficiency 127

HOK Norms for Rotor Spinning 168

XI BOUNDLING , BALING AND CONE PACKING

Work Assignment for Different Categories of Operatives 134

XII MISCELLANEOUS

Supplementary Perticulers for Tables 1 to 20 124

Sitra Norms For Spin. Total Numbers of Worker to be Engaged for 1000 Spindles for 159

Reeled and Cone Yarns

Defination And Explanatory Notes About the Various Productivity 160

Measures Developed by SITRA

Total HOK , Production Per Spindle and OHS 167

Norms for Some Major Counts

Total Complement of overlookers and Maintenance 170

Operatives Upto Spinning in EOU/High-Tech Mills of 30,000 Spindle Size

PAGE No - 54

TABLE - 1

Production Per Scutcher and Weight per Metre of Lap

Lap Length : 40 metres

Calender Roller Speed : 8.5 metres per minute

Count Group Lap Weight Hank of Production Per

(Grams per Lap Scutcher per 8

metre ) Hours (kg) at 85%

Machine Efficiency

6s - 15s 450 0.0013 1561

16s - 25s 425 0.0014 1474

26s - 35s 400 0.0015 1387

36s - 49s 400 0.0015 1387

50s - 71s 375 0.0016 1301

72s - 89s 350 0.0017 1214

90s - 109s 350 0.0017 1214

110s - 120s 350 0.0017 1214

Viscose Staple

Fibre ( VSF ) 400 0.0015 1387

100 % Polyester 350 0.0017 1214

* Without Automatic lap doffing device.

Note : Throughout this publication , the English system and notation is used for describing yarn count

and twist .

TABLE - 2

Production Rates , Sliver Hank and Doffer Speeds

High Production Cards

Count Group Sliver Doffer Production Per Cards

Hank Speed per 8 Hours (kg) at 85%

(rpm) Machine Efficiency

10s - 15s 0.13 28 157

16s - 25s 0.14 27 140

26s - 35s 0.15 26 126

36s - 49s 0.16 25 114

50s - 71s 0.18 23 93

72s - 89s 0.20 22 80

90s - 109s 0.22 21 69

110s - 120s 0.24 20 61

Sitra Norms For Spin. Note : Tension Draft : 1.40

1 It is assumed that 61cm x 107cm ( 24" x 42" )cans are used .

2 Correct humidity conditions must be ensured if high production cards are to perform trouble free.

The generally accepted humidity levels lie in the range of 50 to 55 %.

TABLE - 3

Production Rates , Sliver Hank and Doffer Speeds

Super High Production cards with Autolevellers Chute Feed

Count Group Sliver Doffer Production Per Cards

Hank Speed per 8 Hours (kg) at 85%

(rpm) Machine Efficiency

10s - 15s 0.11 42 294

16s - 25s 0.12 41 263

26s - 35s 0.13 39 231

36s - 49s 0.14 38 209

50s - 71s 0.15 34 174

72s - 89s 0.16 33 159

90s - 109s 0.17 31 140

110s - 120s 0.18 30 128

PAGE No - 55

Note : Tension Draft : 1.40

1 It is assumed that 91cm x 107cm ( 36" x 42" )cans are used .

2 Correct humidity conditions must be ensured if super high production chute feed cards are to

perform trouble free.The generally accepted humidity levels lie in the range of 50 to 55 %.

3 In case of lap - feed the machine efficiency can be expected to be lower by 2 to 4 % .

TABLE - 4

Production Rates , Feed Per Nip,Lap Weight,

Noil % and Machine Efficiency.

High Speed Combers

Speed : 220 nips per minute

Feed Per Nip : 5 mm

No. Of Heads : 8

Lap Wt. Per meter : 60 g for count upto 50s

55 g for count above 50s

Noil Extracted : 18%

Machine Efficiency : 85%

Production per Comber : 177 Kg for count upto 50s

per 8 Hours 162 Kg for counts above 50s

1. For combers equipped with aquto can changers, the above production rates con be more by 3 to 5%

2. Some of the more modern combers are capable of running at higher speeds of the order of 300 nips

per minute or more, in combination with longer feeds of 6 mm per nip, neavier lap weight of 65 to 68 g.

meter and better machine efficiency of 90%, all of which would mean almost double the production rates

compared to the above norms.

TABLE - 5

Production Rates , Sliver Hank, Front Roller Speeds

and Machine Efficiency.

High Speed Draw Frames - Carded Counts.

Count Front Roller Sliver Machine Production per Delivery

Group Speed (mpm) Hank Efficiency* per 8 Hours

Sitra Norms For Spin. (%) Kg Hank

10s - 23s 250 0.13 72 393 113

24s - 27s 250 0.14 73 370 114

28s - 31s 250 0.15 73 345 114

32s - 37s 250 0.17 75 313 117

38s - 47s 250 0.18 75 295 117

48s - 53s 250 0.19 77 287 120

54s - 63s 225 0.20 80 255 113

64s - 79s 225 0.21 80 243 113

80s - 85s 225 0.22 82 238 115

86s - 95s 225 0.23 82 227 115

96s - 100s 225 0.24 85 226 120

* achievable for a sliver breakage rate of 2 [er delivery running hour and an work assignment

of 10 deliveries per tenter

Production per

delivry per = 0.625 * Front roller speed in mpm * Machine Efficiency

8 Hours (Hank) 100

PAGE No - 56

1. The sliver hanks given above are based on mill practice, althogh it is desirable from quality point of

view to maintain hank as would contain 26,000 fibres in sliver cross-section.The sliver hank number

based on this criterion can be obtained from the expression :

1500 Where ug is fibre fineness in micrograms/inch

ug * 26000

2. It is assumed that 46 cm * 107 cm. ( 18" * 42" ) cans are used.

TABLE - 6

Production Rates,Sliver hank.Front Rollar Speed & Machine Efficiency

High Speed Draw frames - Combed counts

Front Production per

Count Roller Sliver Machine Delivery per

Group Speed Hank Effiency 8 hours

(mpm) (%) Kg. Hank

12s - 23s 250 0.13 72 393 113

24s - 27s 250 0.13 73 398 114

28s - 31s 250 0.14 73 370 114

32s - 37s 250 0.16 75 332 117

38s - 47s 250 0.17 75 313 117

48s - 53s 250 0.18 77 303 120

54s - 79s 225 0.19 80 269 113

80s - 95s 225 0.20 82 261 115

96s -109s 225 0.21 85 258 120

110s-120s 225 0.22 85 246 120

* achiveable for a sliver breakage rate of 2 per delivary running hour & an work assingement of 10 deliver

per tenter

Production per

deliver per = 0.625 * Front roller speed in mpm * Machine efficiency

8 hour(Hank) 100

1. Footnotes to table 5 hold good for this table also

2. The same machine efficiency as those for carded stock have been assumed. It is true that the over-parall

-elisation of fibres in the case of combed stock is likely to cause relatively more breaks. But balancing

against this is the elimination of break originating from card such as sliver piecing,stripping,etc. and overall

the stoppages can be taken to be the about same for both combed & carded mixings,of course ignoring the

effect of coarser sliver hank on doff stoppages.



Super High-speed Draw Frames - carded counts

(Single Delivery Machine with Auto-Leveller)




(mpm) (%) Kg. Hank

10s - 23s 500 0.13 74 806 231

24s - 27s 500 0.14 75 759 234

28s - 31s 500 0.15 75 708 234

32s - 37s 500 0.17 77 642 241

38s - 47s 450 0.18 77 545 217

48s - 53s 450 0.19 79 530 222

54s - 63s 450 0.20 82 523 231

64s - 79s 450 0.21 82 498 231

80s - 85s 350 0.22 84 379 184

86s - 95s 350 0.23 84 362 184

96s -100s 350 0.24 84 347 184

PAGE No - 57

Production per

delivry per = 0.625 * Front roller speed in mpm * Machine Efficiency

8 Hours (Hank) 100


2. The machine efficiency assumed are achievable for a sliver breakage rate of not more than 2 per delivery

running hour & work assignment of 5 deliveries per tenter.

3. It is assumed that 46 cm. * 107 cm. (18" * 42" ) cans are used.

TABLE - 8


Super High Speed Draw frames - Combed counts

(Single Delivery Machine with Auto-Leveller)




(mpm) (%) Kg. Hank

12s - 23s 350 0.13 74 565 162

24s - 27s 350 0.13 75 572 164

28s - 31s 350 0.14 75 532 164

32s - 37s 300 0.16 77 409 144

38s - 47s 300 0.17 77 385 144

48s - 53s 300 0.18 79 373 148

54s - 79s 300 0.19 82 367 154

80s - 95s 300 0.20 84 357 158

96s -109s 300 0.21 85 344 159

110s-120s 300 0.22 85 329 159

Production per

deliver per = 0.625 * Front roller speed in mpm * Machine efficiency

8 hour(Hank) 100


2. The same machine efficiency as those for carded stock have been assumed. It is true that the over-parall

-elisation of fibres in the case of combed stock is likely to cause relatively more breaks. But balancing

against this is the elimination of break originating from card such as sliver piecing,stripping,etc. and overall

Sitra Norms For Spin. the stoppages can be taken to be the about same for both combed & carded mixings,of course ignoring the

effect of coarser sliver hank on doff stoppages.

NOTES TO TABLES 9 & 10

Fly Frames

1. The indicated machine efficiencies can be achived for the following breakage rates: 5 or less per 100 spdl

hours in count less than 16s (with roving hank less than or equal to 1.0) where 2 fly frames are assigned

per tenter. In all other counts where 3 fly frames are assigned per tenter,the breakage rate should be 3 or

less per 100 spindle hours.

2. If tenter helps doffing boys when the frame is stopped for doffing,the machine efficiency would be higher by

2 to 3% dependind on the hank & number of doffing boys engaged.

3. It is assumed that 46 cm. * 107 cm. (18" * 42" ) cans are used.

4. On more modern frames,20 to 25% higher spdl speed than those indicated in the table can be maintained

5. Production per 7.2 * spindle speed Machine efficiency

spindle per = *

8 hours(g.) TPI * count 100000

spindle speed Machine efficiency

-do-(Hanks) = *

TPI 6300

PAGE No - 58

TABLE - 9

Production Rates,Spindle Speeds,Roving hank,Twist Multipliers

& Machine Efficiency

Fly Frames - Carded counts

Count Spindle Roving Twist Machine Proudction per

Group speed Hank Multi- Effici- spindle per

(rpm) plier ency 8 Hours

(%) Kg. Hanks

6s - 11s 800 0.90 1.90 83.0 2.95 5.9

12s - 17s 875 1.00 1.75 83.0 2.99 6.6

18s - 23s 1100 1.05 1.55 81.5 3.87 8.9

24s - 27s 1100 1.15 1.50 82.0 3.51 8.9

28s - 31s 1100 1.30 1.45 85.0 3.13 9.0

32s - 37s 1100 1.45 1.40 86.0 2.79 8.9

38s - 43s 1100 1.55 1.35 86.0 2.61 8.9

44s - 47s 1100 1.80 1.25 86.5 2.27 9.0

48s - 53s 1100 1.90 1.25 87.0 2.10 8.8

54s - 57s 1100 2.05 1.25 87.0 1.88 8.5

58s - 63s 1100 2.15 1.20 87.0 1.83 8.7

64s - 69s 1100 2.35 1.20 87.0 1.60 8.3

70s - 79s 1100 2.50 1.15 88.0 1.53 8.4

80s - 85s 1100 2.80 1.10 88.0 1.35 8.4

86s - 95s 1100 3.00 1.10 88.0 1.22 8.0

96s-100s 1100 3.15 1.10 88.0 1.13 7.9

20s - 25s VSF 800 0.95 0.80 78.0 6.07 12.7

26s - 31s VSF 800 1.15 0.80 80.5 4.70 11.9

40s VSF 800 1.35 0.80 84.0 3.86 11.5

VSF : Viscose staple fibre

TPI = Twist multiplier * Roving hank


Production Rates,Spindle Speeds,Roving hank,Twist Multipliers

& Machine Efficiency

Fly Frames - Combed Count & polyester Blends

Count Spindle Roving Twist Machine Proudction per

Group speed Hank Multi- Effici- spindle per

(rpm) plier ency 8 Hours

(%) Kg. Hanks

12s - 17s 875 1.00 1.55 82.5 3.35 7.4

18s - 23s 1100 1.05 1.40 81.0 4.26 9.9

24s - 27s 1100 1.10 1.40 81.5 4.00 9.7

28s - 31s 1100 1.25 1.35 85.0 3.57 9.8

32s - 37s 1100 1.35 1.30 85.0 3.30 9.8

38s - 43s 1100 1.60 1.30 86.0 2.59 9.2

44s - 47s 1100 1.70 1.20 86.0 2.56 9.6

48s - 53s 1100 1.80 1.20 86.5 2.36 9.4

54s - 57s 1100 1.95 1.20 87.0 2.11 9.0

58s - 63s 1100 2.05 1.20 87.0 1.96 8.8

64s - 69s 1100 2.15 1.15 87.0 1.90 9.0

70s - 79s 1100 2.35 1.10 87.5 1.75 9.0

PAGE NO = 59

80s - 85s 1100 2.60 1.15 88.0 1.45 8.3

86s - 95s 1100 2.80 1.10 88.0 1.35 8.4

96s-100s 1100 2.95 1.10 88.0 1.25 8.1

110s-120s 1100 3.15 1.05 88.0 1.19 8.3

20s P/C 700 1.05 0.80 80.0 4.68 10.8

32s P/C 700 1.35 0.80 85.0 3.41 10.2

44s P/C 700 1.70 0.80 86.5 2.46 9.2

50s P/C 700 1.80 0.80 86.5 2.26 9.0

60s P/C 700 2.05 0.80 87.0 1.87 8.4

80s P/C 700 2.60 0.80 88.0 1.32 7.6

20s P/V 700 1.10 0.80 80.5 4.40 10.6

30s P/V 700 1.30 0.80 84.5 3.59 10.3

40s P/V 700 1.50 0.80 85.5 2.93 9.7

45s P/V 700 1.70 0.80 86.5 2.46 9.2

50s P/V 700 1.90 0.80 87.0 2.09 8.8

TPI = Twist multiplier * Roving hank

P/C : Polyester cotton Blends P/V : Polyester Viscose Blends

NOTES TO TABLES 11 & 12

The norms for production per spindle given in table 11 & 12 are achievable under the following condition :

1. The spindle lifts & ring diameters assumed for different count ranges are as follows.

Count Spindle lift * Ring diameter Cop Content

Below 20s 8" * 1 3/4" (203 mm. * 44 mm.) 80 g

20s & above 7" * 1 5/8" (178 mm. * 41 mm.) 60 g

2. The interrelationships between end breakage rates & tenter work assingnments are given in table 27 for some of

the major counts.

3. Higher spindle speeds(than those given as norms),say, of the order of 18000 rpm or above are possible on ring

frames with 152 mm spindle lift & 38 mm ring diameter,other factor permitting.

4. Relative humidity should be controlled within 50 to 60%

5. In the case of blended yarns,it may be necessary to use special type of travellers,e.g.spiv,in order to control

hairness within acceptable limits.

6. For majar count the production per spindle figures given in these two tables are also recast in term of the corres-

Sitra Norms For Spin. -ponding hanks (table 36) to allow direct comparison with hank indicator readings

7. The norms for losses in ring frame machine efficiency due to machine maintenance,pneumafil waste,idle spindle

& doffing are given in table 13. The losses which can arise from yarn contraction are shown in table 14.

TABLE - 11

Production per Spindle,Spindle Speeds,Twist Multiplier,

TPI and Machine Efficiency

Ring Frames - Carded Counts

Spindle Twist* TPI Machine Production * *

Count Speed Multiplier Efficiency per Spindle

(rpm) (%) per 8 Hours

6s 8000 4.5 11.02 83 723

8s 9500 4.5 12.73 85 570.9

10s 11000 4.5 14.23 86 478.7

12s 12000 4.5 15.59 87.5 404.1

14s 12000 4.5 16.84 88.5 324.3

16s 12500 4.4 17.6 89 284.4

18s 13000 4.4 18.67 89.5 249.3

20s 14000 4.4 19.68 90 230.5

20s H 13000 3.8 16.99 90.5 249.3

20s HT 14000 7.5 33.54 76.5 115

PAGE No - 60

TABLE - 11 ( Contd.)



Ring Frame - Carded Counts.




20s VSF 12500 3.5 14.53 91.5 283.4

22s 14000 4.4 20.64 90 199.8

24s 14400 4.4 21.56 91 181.3

25s 14400 4.4 22.00 91 170.6

26s 14400 4.4 22.44 91 161.7

28s 14400 4.4 23.28 91 144.7

30s 15500 4.4 24.1 91 140.5

30s H 14500 3.7 20.27 92 157.9

31s VSF 13000 3.25 18.10 93 155.1

32s 15500 4.2 24.32 91.5 131.2

34s 15500 4.3 25.07 91.5 119.8

34s H 14700 3.6 20.99 92.5 137.2

36s 15500 4.3 25.8 91.5 109.9

38s 15500 4.3 26.51 92 101.9

40s 15600 4.3 27.2 92 95

40s H 14700 3.6 22.77 92.5 107.5

40s VSF 14000 3.35 21.19 93.5 111.2

42s 16000 4.2 27.22 92 92.7

44s 16000 4.2 27.86 92.5 86.9

46s 16000 4.2 28.49 92.5 81.3

47s 16000 4.2 28.79 92.5 78.8

48s 16000 4.2 29.1 92.5 76.3

50s 16000 4.1 28.99 92.5 73.5

60s 16500 4.1 31.76 93 58

Sitra Norms For Spin. 60s HT 16500 5.5 42.6 86 40

60s VSF 14000 3.35 25.95 94 60.9

62s 16500 4.1 32.28 93 55.2

64s 16500 4.1 32.8 93 52.6

70s 16500 4.1 34.3 93 46

80s 16500 4.0 35.78 93 38.6

84s 16500 4.0 36.66 93.5 36.1

100s 16500 4.0 40 93.5 27.8

H : Hosiery HT : High Twist VSF : Viscose Staple Fibre

* The values shown are largely based on spinning mill's practice.

composite mills are, in general,about 0.1 to 0.2 higher, particularly in coarser and medium counts.

composite mills may,therefore, corrospondingly reduce the production per spindle norms indicated

here

** Production per spindle = 7.2 * Spindle Speed * Machine Efficiency

per 8 Hours (g.) Tpi * Count 100

PAGE - 61

TABLE - 12



Ring Frame - Combed Counts. And Polyester Blends




12s 12500 4.3 14.90 87.5 440.4

14s 12500 4.3 16.09 88.5 353.6

16s 13000 4.1 16.40 89.5 319.3

18s 13500 4.1 17.39 90.0 279.5

20s 14500 4.0 17.89 90.0 262.6

20s H 13500 3.5 15.65 90.5 281.0

22s 14500 4.0 18.76 90.5 228.9

24s 15000 4.0 19.60 91.0 208.9

25s 15000 4.0 20.00 91.0 196.6

26s 15000 4.0 20.40 91.0 185.3

28s 15000 4.0 21.17 91.5 166.7

30s 15000 4.0 21.91 91.5 160.4

30s H 15000 3.5 19.17 92.0 172.8

32s 16000 4.0 22.63 91.5 145.6

34s 16000 4.0 23.32 92.0 133.7

34s H 15000 3.5 20.41 92.5 144.0

36s 16000 3.9 23.40 92.0 125.8

38s 16000 3.9 24.04 92.0 116.0

40s 16000 3.9 24.67 92.5 108.0

40s H 15500 3.4 21.50 92.5 120.0

55s HT 16500 5.5 40.79 85.5 45.3

60s 17000 3.9 30.21 93.0 62.8

62s 17000 3.9 30.71 93.0 59.8

Sitra Norms For Spin. 64s 17000 3.9 31.20 93.0 57.0

70s 17000 3.9 32.63 93.0 49.8

80s 17000 3.8 33.99 93.5 42.1

90s 17000 3.8 36.05 93.5 35.3

100s 17000 3.9 39.00 93.5 29.3

120s 17000 3.9 42.72 93.5 22.3

30s P/C 13500 3.6 19.72 92.0 151.2

50s P/C 15500 3.6 25.46 93.0 81.5

60s P/C 15500 3.6 27.89 93.5 62.4

60s P/CHT 15500 5 38.73 87.0 41.8

80s P/C 16000 3.6 32.20 93.5 41.8

90s P/C 17000 3.8 36.05 93.5 35.3

32s P/V 13000 3 16.97 92.5 159.4

40s P/V 15000 3 18.97 92.5 131.7

60s P/V 16000 3 23.24 93.5 77.2

80s P/V 16000 3 26.83 94.0 50.5

H: Hosiery HT: High Twist

P/C :Polyester / Cotton P/V : Polester / Viscose

* The values shown are largely based on spinning mill's practice.

composite mills are, in general,about 0.1 to 0.2 higher, particularly in coarser and medium counts.

composite mills may,therefore, corrospondingly reduce the production per spindle norms indicated

here



PAGE - 62 TABLE - 13

BREAK-UP OF LOSS * IN MACHINE EFFICIENCY IN RING FRAMES

Maintenance ** 1.0% Idle spindles 0.1%

Pneumafil waste+ Loss due to doffing

3.5% for counts 10s & below 0.8% per doff per shift

3.0% for counts 11s to 19s Yarn contraction % due to twist

2.5% for counts 20s & above see table 14

* All the losses are not cumulative

**Includes stoppages for routine cleaning & traveller change.All other stopages are taken as loss in machine utilisation

* Includes lapping (bonda) waste.

TABLE - 14

Percentage contraction in cotton yarns

Due to Twist in Ring spinning

Twist Yarn Twist Yarn

multiplier contraction multiplier contraction

(%) (%)

3.00 1.84 4.10 2.74

3.10 1.87 4.20 2.90

3.20 1.90 4.25 2.98

3.30 1.94 4.30 3.07

3.40 2.00 4.40 3.28

3.50 2.08 4.50 3.54

3.60 2.16 4.60 3.96

3.70 2.26 4.70 4.55

3.75 2.31 4.75 4.90

3.80 2.37 4.80 5.41

3.90 2.49 4.90 6.70

4.00 2.61 5.00 8.71

1. As regard viscose staple fibre yarns,deduct 0.5 from the contraction values for the corresponding twist multiplier

2. The yarn contraction percentage for twist multiplier outside the range covered in the above table may be the

determined by actual mesurment of a new spindles,of the reduction in the length of strand between the front roller

& the bobbin.An average based on about 20 spindles can be trusted to give a reliable estimate.


Proudction per Spindle,spindle Speeds,TPI & Machine Efficiency

Ring Doubling Frames

Spindle Machine Production **

Count speed TPI Efficiency per spindle

(rpm) (%) per 8 Hours (g)

2/20s 9600 13.78 92.5 464.0

2/24s 9600 15.09 94.0 358.8

2/26s 9600 15.71 94.5 319.8

2/30s 9600 16.87 95.0 259.5

2/36S 9600 17.64 95.5 207.9

2/40s 9600 18.59 96.0 178.5

2/60s 10000 22.23 97.0 104.7

2/60s C 10000 21.15 97.0 110.1

2/80s 10500 25.05 97.0 73.2

2/80s C 10500 23.79 97.0 77.1

2/100s 10500 28 97.5 52.7

2/100s C 10500 26.6 97.5 55.4

2/120s C 10500 29.14 97.5 42.2

2/20s VSF 9600 9.39 90.0 662.5

2/31s VSF 9600 11.69 94.0 358.6

2/40s VSF 9600 14.17 95.0 231.7

* 0.7 * the corresponding single yarn tpi given in table 11 & 12. C: Combed VSF: Viscose Staple Fibre

1. Spindle lift 203mm (8")& ring diameter 51mm (2")

2. The machine efficiency figures are applicable only to doubling from cone or cheeses.

3. Doubling twist : s- direction




Proudction per Spindle,spindle Speeds,TPI , Machine Efficiency

& Spindles per Tenter

Two-for-one-Twister

Spindle Machine Spindles Production **

Count speed TPI Efficiency per per spindle

(rpm) (%) tenter per 8 Hours

(g.)

2/20s 10000 13.78 93.0 288 972

2/30s 10500 16.87 95.5 576 571

2/32s 10500 17.02 95.5 576 530

2/36s 10500 18.59 95.5 576 432

2/40s 10500 22.23 96.5 576 328

2/40s C 11000 17.27 96.5 576 443

The above figure are roughly double the production rate norms for the corresponding count in ring doubling.

** Production per spindle = 7.2 * Spindle Speed * 2 * Machine Efficiency

per 8 Hours (g.) Tpi * Resultant Count * 100

NOTES TO TABLE 17

The production per reeler figures have been arrived at on the following assumption :

Reel speed : 411.5 metres per minute

(450 yards per minute)

Pegs per Reel : 40

Creel Package weight : count single Double

yarns yarns

Cotton Yarn

Beloe 20s 80 60

20s & above 100 100

VSF Yarn 8% 5%

Sitra Norms For Spin. Higher * Higher *

* than that for the corresponding cotton yarn

End Break : One per 40 hanks of 840 yards each

Tie : Single count for all range of counts

Work Load : 85% wherever work opportunity exists

Production per 18.144 * 10.of doffs

Reeler per for SHPR

8 hours (kg.) Count

for 840 yards

hank For DHCR 18.144 * No.of doff * 2

(40 pege per reel) or DHPR

Count

In the case of 1000 metre hank,multiply the figure obtained fom the above formula by 1.3.


Production & No. of Doffs per Reeler

- Single Hank Plain,Double Hank Cross & Double Hank Plain Reeling

Single Hank Double Hank Double Hank

Plain Reels Cross Reels Plain Reels

Proudction No. of Proudction No.of Proudction No.of

Count per Reeler Doffs per Reeler Doffs per Reeler Doffs

per 8 Hours per 8 Hours per 8 Hours

(Kg.) (Kg.) (Kg.)

10s 68.9 38 98.0 27 98.0 27

14s 57.0 44 80.4 31 77.8 30

16s 51.0 45 72.6 32 70.3 31

18s 46.4 46 66.5 33 64.5 32

20s 39.9 44 56.2 31 54.4 30

24s 34.8 46 49.9 33 48.4 32

26s 32.8 47 46.1 33 44.7 32

30s 29.0 48 41.1 34 39.9 33

32s 27.2 48 39.7 35 38.6 34

36s 24.7 49 36.3 36 35.3 35

40s 21.3 47 32.7 36 30.8 34

44s 19.4 47 30.5 37 28.0 34

60s 14.8 49 23.6 39 21.8 36

80s 11.3 50 18.1 40 16.8 37

100s 9.3 51 14.9 41 13.8 38

120s 7.7 51 12.7 42 11.5 38

2/20s 74.4 41 108.9 30 105.2 29

2/30s 55.6 46 79.8 33 77.4 32

2/40s 40.8 45 63.5 35 59.9 33

2/60s 29.0 48 46.0 38 43.5 36

2/80s 22.7 50 36.3 40 33.6 37

2/100s 18.1 50 29.8 41 26.9 37

2/120s 15.4 51 24.8 41 23.0 38

Sitra Norms For Spin. 20s VSF 66.0 28 **

31s VSF 47.2 31 **

40s VSF 37.7 32 **

2/40s vsf 70.8 30 **

VSF : Viscose Staple Fibre

* 80 hanks doffs

** A hank equals 1000 metres compared with 840 yardss in all other cases.

NOTES TO TABLE 18 & 19

Conventional Cone Winding

Prouction per tenter is based on the following assumption :

1. Winding-on speed : 550 mpm

2. Full cone weight : 1 Kg.

3. Creel package weight (g) : Count Single Double

Yarns Yarns

Below 20s 80 100

20s & above 60 100

4. Type of clearer : Mechanical Yarn clearer (MYC)

Electronic Yarn clearer (EYC)

5. End breaks per 1 lakh metre :

Single Yarn Double Yarn

Count with with Count with with

MYC EYC MYC EYC

10s To 19s 20 40 2/10s To 2/18s 12 24

20s To 39s 12 24 2/19s To 2/36s 10 20

40s To 59s 10 20 2/37s To 2/70s 6 12

60s To 79s 8 16 2/71s To 2/90s 5 10

80s To 99s 7 14 2/91s To 2/120s 4 8

100s To 120s 6 12

6. Work load : 85% wherever work opprtunity exists

PAGE - 65 Table 18

Production per Tenter, Work Assignment & Machine Efficiency

Coneventional Cone Winding - Single Yarns

Count Drums MYC EYC EYC with splicer

Assigned Machine prod./ Machine prod./ Machine prod./

per efficiency Tenter/ efficiency Tenter/ efficiency Tenter/

Tenter (%) 8 Hours (%) 8 Hours (%) 8 Hours

(Kg.) (Kg.) (Kg.)

10s 12 77.0 144 68.5 128 57.5 108

14s 15 79.0 132 67.5 113 57.0 95

16s 15 81.5 119 73.5 107 61.5 90

18s 20 73.0 126 57.0 99 48.0 83

20s 24 59.5 111 51.0 95 43.0 80

24s 24 69.0 108 57.5 90 48.5 76

26s 24 73.5 106 60.5 87 51.0 73

30s 24 81.0 101 66.5 83 56.0 70

32s 24 82.0 96 69.0 81 58.5 68

34s 24 83.0 91 71.5 79 60.5 67

36s 24 83.5 87 74.0 77 62.5 65

39s 30 77.5 93 59.5 71 50.5 61

40s 30 83.0 97 67.0 78 56.5 66

44s 30 84.0 89 70.5 75 59.5 63

60s 40 83.5 87 65.0 68 55.5 58

70s 40 85.0 76 70.5 63 59.5 53

80s 60 66.0 77 47.5 56 40.5 47

90s 60 70.5 73 49.5 51 42.5 44

100s 60 80.0 75 57.0 53 49.0 46

120s 60 82.5 64 61.0 48 52.5 41

Table 19

Sitra Norms For Spin. Production per Tenter, Work Assignment & Machine Efficiency

Coneventional Cone Winding - Double Yarns

Count Drums MYC EYC

AssignedMachine prod./ Machine prod./

per efficiency Tenter/ efficiency Tenter/

Tenter (%) 8 Hours (%) 8 Hours

(Kg.) (Kg.)

2/10s 8 75.0 187 73.0 182

2/14s 12 73.0 195 67.0 179

2/16s 12 78.5 184 75.0 175

2/18s 15 72.5 188 65.0 169

2/20s 15 79.5 186 73.5 172

2/24s 15 83.0 162 80.0 156

2/26s 20 75.5 181 66.0 158

2/30s 20 81.5 169 73.0 152

2/32s 24 73.5 172 62.5 146

2/34s 24 77.5 171 65.0 143

2/36s 24 81.0 168 68.0 141

2/39s 24 84.0 161 82.0 157

2/40s 30 75.0 175 65.5 153

2/44s 30 81.5 173 70.5 150

2/60s 30 85.5 133 82.5 129

2/70s 40 82.0 146 68.0 121

2/80s 40 86.0 134 81.5 127

2/90s 40 87.0 121 84.0 116

2/100s 40 88.0 110 86.0 107

2/120s 40 88.5 92 87.0 90

PAGE - 66 NOTES TO TABLE 20

Automatic Cone Winding

1. Type of Machine : Autowinder fittd with individual 'drum' splicer,auto doffer & round magazine cop feed

2. Winding on speed : 1200 mpm

3. Creel package weight(g) : Below 20s - 80

: 20s & above - 60

4. Full cone weight : 2 Kg.

5. End break per 1lakh metres : upto 19s - 50

20s to 29s - 45

30s to 39s - 40

40s to 69s - 35

70s to above - 30

6. Repeaters : 10 %

7. Cop regection : 10 %

8. Work load : 85 %

TABLE - 20

Production per Tenter, Work Assignment & Machine Efficiency

Automatic Cone Winding

No. of Machine Production / No. of Machine Production /

Count Drums/ Efficiency Tenter / Count Drums/ Efficiency Tenter /

Tenter (%) 8 Hours (kg.) Tenter (%) 8 Hours (kg.)

10s 15 77.0 393 38s 50 74.0 331

12s 20 78.0 442 40s 50 78.0 332

14s 24 76.0 443 46s 60 75.0 333

16s 30 69.0 440 50s 60 81.0 331

18s 30 78.0 442 56s 60 87.5 319

20s 30 65.0 332 60s 60 88.5 301

24s 30 78.0 332 70s 90 76.0 332

26s 30 82.0 322 80s 90 86.5 331

30s 40 73.0 331 90s 90 90.5 308

Sitra Norms For Spin. 31s 40 73.0 320 100s 120 81.5 333

34s 40 83.0 332 120s 120 90.5 308

36s 40 84.5 319

Supplementary Particular for Table 1 To 20

Production Formulae

SCUTCHER 8.9 s * d S - Speed of lap roller (rpm)

1000 * H kg. d - Dia of lap roller (cm.)

H - Hank of lap

S - Speed of 69 cm.

S (27')dia. Doffer (rpm)

CARD 0.855 * H kg. H - Hank of lap

Tension Draft - 1.4

L - Lap weight in g. per metre

0.0384 S - Speed in nips per min.

COMBER 1000 * LSF(100-W)kg. F - Feed in mm. Per nip

W -Noil extracted in %

DRAW FRAME 0.069 * S Hanks S - Speed of lap roller (rpm)

FLY FRAME 0.053 * S Hanks 35 mm.roller dia.

RING FRAME 0.050 * S Hanks 27 mm.roller dia.

25.4 mm.roller dia.

0.2835 * S S - Winding on speed in mpm

CONE WINDING DRUM C C - Count

Conversion Formulae Hanks * 0.4536 per delivery/spindle

DRAW FRAME & FLY FRAME Hanks to kilograms = Sliver/roving Hank

GENERAL Length of yarn in metres = 1.693 * Count * Package Weight (g)


Production per Rotor,Rotor Speeds,Twist Multiplier,TPI & M/C Efficiency

Rotor Spinning

Count Rotor T.M. TPI Machine Production *per

speed Efficiency Rotor per 8 hours

rpm (%) (kg)

6s 70000 5 12.25 93 9.38

7s 70000 5 13.23 93 5.06

8s 70000 5 14.14 95 4.23

10s 70000 5 15.81 95 3.03

12s 70000 5 17.32 95 2.3

14s 80000 5 18.71 95 2.09

16s 80000 5 20.00 95 1.71

20s 80000 5 22.36 95 1.22

Number of Rotors per machine = 160

Production per 7.2 * Rotor speed Machine Efficiency

rotor per = *

8 hours (kg) TPI * Count 100

The above figure should be taken as only a broad guide to the best production rate obtained in the mills.

The actual speed as well as machine efficiencies that can be maintained in a given machine would very much depend

on the techonological sophistication of the machine as well as type of raw material used.

TABLE - 22 TABLE - 23

Draft Used on Fly-Frames Draft Used on Ring-Frames

Count Draft Count Draft

10s 8.0 10s 14

16s 8.5 16s 18

Sitra Norms For Spin. 20s 9.0 20s 20

26s 9.0 26s 23

30s 10.0 30s 25

40s 10.0 40s 27

44s 11.0 44s 30

50s 11.0 50s 30

60s 12.0 60s 31

64s 12.5 64s 31

70s 13.5 70s 32

80s 14.5 80s 32

90s 15.0 90s 32

100s 15.0 100s 33

The following relationship will approximately give the above values. For count 10s to 44s : 4.5 count ; for

count 50s to 70s : 4.0 count ; & for count 80s to 100s : 3.3 count .

TABLE - 24

Traveller Number's to be Used in Ring spining

Count Traveller No Count Traveller No Count Traveller No

10s 7 to 9 40s 6/0 to 8/0 20s VSF 4 to 6

12s 8 to 10 44s 6/0 to 8/0 30s VSF 2 to 1/0

14s 5 to 7 50s 10/0 to 12/0 40s VSF 3/0 to 5/0

16s 4 to 6 60s 11/0 to 13/0 20s P/C 5 to 7

18s 3 to 5 64s 12/0 to 14/0 32s P/C 1 to 3

20s 1/0 to 2 70s 13/0 to 15/0 44s P/C 1/0 to 3/0

24s 1 to 2/0 80s 17/0 to 19/0 50s P/C 3/0 to 5/0

26s 2/0 to 4/0 90s 18/0 to 20/0 60s P/C 4/0 to 6/0

30s 2/0 to 4/0 100s 20/0 to 22/0 64s P/C 5/0 to 7/0

36s 4/0 to 6/0 120s 22/0 to 24/0 80s P/C 7/0 to 9/0

VSF : Viscose Staple Fibre P/C : Polyester Cotton Blend

PAGE - 68

1. The traveller number for different counts may be taken to corrospond to the spindle speeds Shown in Tables 11 & 12

2. The traveller size depend also on ring dimenssions,rig condition,yarn lea strength and so on. In consequence,the

the correct traveller size to suit particualr conditions can be determined by actual trial alone, and the details provided

above should prove useful in this context.

3. No less imperative is to ensure that the traveller and ring are matched in shape. Also a suitable wire section should .

be chosen

TABLE - 25

Traveller Number's to be Used in Ring Doubling

Count Traveller No.

2/20s 9 to 12

2/24s 8 to 11

2/30s 8 to 11

2/40s 4 to 7

2/60s 1/0 to 3

2/80s 3/0 to 1

2/100s 2/0 to 5/0

The correct traveller size to suit given conditions can be determined only by actual trials. The details shown

above would provide useful starting point.

TABLE - 26

Work Assignments/Operatives * for Attaining

19 HOK Upto Spinning in SITRA Productivity Surveys

Mixing & BlowroomMixing Attenant Cotton One man for 20,000 kg. Oflap

( stack mixing) for 26 shifts of 8 hours each.


Man - Made One man for 24,000 kg. Oflap

fibres for 26 shifts of 8 hours each.

Scutter attendant One man for 2 or 3 scutters fitted with

automaticlap doffing device,upto a maximum

of 3650 kg. Oflap

Back attendant One man for upto 3650 kg oflap

Jobber One during day shift only.

CardsCan tenter, High Production One man for 7 cards, subject to

Fly carrier, etc. a maximum of 600 kg. Of sliver

( team work ) production; can size: 24'' * 42''

Others 0.08 operative per card shift.

CombersTenter High Speed 6 comber per tenter

Draw FramesTenters High speed 10 deliveries per tenter

Super High speed

with Auto - leveller

(1-delivery machine)

PAGE - 69 Table 26 ( Contd. )

FlyframeTenter Three machines per tenter : can size : 16'' * 42''. For hank 1.00 and coarser,

two machine per tenter..Spindle per flyframe = 120

Doffers 1100 spindle doffs

Others Approximately 0.30 operative per fly frame shift. The categories include

(Common to cleaning gang, fitters, fitter helpers and bobbin carriers

drawing & fly

frames)

Ring FrameTenters :

Cotton Counts Man - Made Fibre & Blends

Count sides spindles Count sides spindles

6s to 9s 2 440 upto 29s 8 1760

10sto 15s 3 660 30s to 44s 9 1980

16s to 19s 4 880 45s & Finer 10 220

20s to 26s 5 1100

27s to 35s 6 1320

36s to 44s 7 1540

45s to 60s 8 1760

61s to 80s 9 1980

81s & Finer 10 2200

One side = 220 Spindles

Reserve Tenters 10% of the tenter

Reliver for 24 10% of the tenters and reserve tenters

hours working

Doffers 4200 spindle doffs

Sitra Norms For Spin. (duties include sweeping also)

All others Upto 19s - 0.50

(Operative per 20s to 35s - 0.40

1000 spindle) 36s to 60s - 0.35

61s & above - 0.30

ReelingRefer to Table 17

Cone WindingRefer to Table 18,19 & 20

Ring Doubling(Cheese or cone -fed)

The work assignment is the same as for the corosponding single yarn component

(e.g. for 2/20s, 5 sides are assigned per tenter).

Bundling And BalingBUNDLING

Counts Bundles/Operatives/Shift

upto 22s & 60s - 79s 10023s - 29s & 80s - 90s 80

30s - 90s & 100s and above 70

40s - 59 s 60

Bundle weight is taken as 2.27 kg. For 60s and above. In counts less than 60s, one bundle weight 4.54 kg.

The employment of knotters, weighters and pressers is in the ratio 3:1:1:5.

BALING 16 bales per baler per 8 hours.

CONE PACKING 20 Bags of 50 kg each per packer per 8 hours.

PAGE - 70

NOTES TO TABLE - 27

If, because of spindle interference, it is not possible to ensure lower and end breakege ratea at higher

assignments as indicated in the table, the pneumafil waste will increase, resulting in proportionate reduction in production

per spindle. Inter relationships between spindle efficiency and amount of pneumafil waste are given Table - 28.

The following simplified expression may also be used to give an indication of the allowable and breaks for

different tenter assignments in ring frames.

b = 125 - 30 ………………………………… ( 1 )

n c

Where

b = end breaks per 100 spindle hours

c = count

n = number od sides assigned for a tenter

( one side = 220 spindles )

Breakage rates obtained by applying the above expressions may not be exactly equal to that given in Table-27,

as the end breakage figures for various counts and tenter assignments given in the table have been arrived at from more

elaborate equations using count specific assumptions.

Altenatively, to quickly work out the number of sides corresponding to different levels of end breaks, the

following expression may be applied.

n = 125 …………………………………. ( 2 )

b + 30 / c

Application of the above formulae would show that a unit increase in end breaks is equivalent to reducing

the assignments by 0.2 to 0.3 sides per tenter . Also , influence of count on work assignments depends upon the level

of end breaks.

For a given roving bobbin weight and production per spindle in ring spinning. The allowable end breaks are given by

Sitra Norms For Spin. b + s(r-p)/40 ……………………………………….. (3)

Where b = breaks per 100 spindle hours estimated from formula (1)

s = standard production per spindle as given in table 11 & 12

r = roving bobbin weight in the mill as a ratio of 1.3 kg.

p = production rate in the mill as a ratio of 's'

If interference loss alone is considered, then an increase in work assignment would be more paying in many

situations. However, viewed from the overall profitability, a mill should first examine the scope for increasing spindle

speed to the maximum possible level by ensuring high standards of maintenance, good house-keeping, and so on. Once

the maximum possible spindle speed is reached, then the scope for increasing the work assignment could be explored.

The following general expression gives the realationship between economics of higher work assignments

that of higher production per spindle.

S = 3.3 W (1 - g)(P-E)

n Per

Where S = Saving in wages per spindle per year by increasing work assignment from E to P sides

per tenter

W = Existing wages per tenter per year (Rs) including all the benefits

gx = % increasing in wages for higher assignment

r = saving from 1% higher production per spindle per year in Rs.

X = % increase in work assignment = 100 (P-E)

E

PAGE - 71

TABLE - 27

End Break allowable for 100 Spindle Hours in

Ring Frames For Different Work Assignment to Tenter

Count Sides per End Breaks per Count Sides per End Breaks per

Tenter 100 Spdl/Hours Tenter 100 Spdl/Hours

6s 2 43 100s 6 16

3 23 8 12

10s 2 47 10 9

3 28 12 7

16s 2 49 120s 6 16

3 30 8 12

4 20 10 9

20s 4 21 12 7

6 12 20s VSF 4 17

8 8 6 10

30s 4 23 8 6

6 14 31s VSF 6 11

8 9 8 8

40a 4 24 10 5

6 15 12 4

8 11 40s VSF 6 13

10 8 8 9

60s 6 16 10 6

8 11 12 5

10 9 14 4

12 7 60s VSF 6 13

Sitra Norms For Spin. 80s 6 16 8 9

8 12 10 7

10 9 12 6

12 7 14 5

30s P/C 6 11 32s P/V 10 5

8 8 12 4

10 5 42s P/V 6 12

12 4 8 8

60s P/C 6 13 10 6

8 9 12 5

10 7 60s P/V 6 13

12 6 8 9

14 4 10 7

80s P/C 6 14 12 5

8 10 14 4

10 7 80s P/V 6 13

12 6 8 10

14 5 10 7

30s P/V 6 11 12 6

8 7 14 5

* One side = 220 spindle VSF : Viscose Staple Fibre

P/C : Polyester Cotton P/V : Polyester Viscose

1. Spindle speed & machine efficiencies corrospond to those given in Table 11 & 12.

2. Work load is taken as 85%

3. Pnemafil waste is as shown in Table 13

4. Cleaning time per 400 spindles per shift of 8 hours : 25 minutes for 16s & below. 15 minutes for 16S & 39s

and 10 minutes for counts 40s & above. For man - made fibre & blends : 10 minutes.

5. Creel bobbin content : 1.3 kg.

6. Tenter's duties include creel changing.

PAGE - 72

NOTES TO TABLE 28

The question of opimum spindle assignment to the ring frame tenter is essentially an economic problem.

The decision with regard to the number of spindles to be assigned per tenter has to be taken, after comparing the

the loss which would arise from lower spindle efficiency against the gains to be derived from reducd labpur cost.

The amount of pnemafil waste,which is defined to include lapping (bonda) waste also,is markedly sensetive

to the changes in spindle efficiency, and hence furnishes a reliable and practical measure in this context. Any

increase in pnemafil waste can be taken to represent a proportionate in production.

The table would enable a mill :

1. To know the amount of pnamafil waste to be expected for a given level of end breaks and creel running time for

for a given work assignment. If the actual waste is higher,it may reflect one of the two things: either the tenter do not

promptly attend to end breaks or they are devoting more time ( than 15 minutes per 400 spindles per shift of 8 hours

as taken arriving at the figures) to clening.

2. To decide the levels at which end breakages should be mentioned for various work assignments.

Example

What should be the breakage rate in 60s which would enable six side to be assigned per tenter at 85% work load

and an acceptablepnemafil of 2.0%?,.The creel bobbin content is 1.0 kg., which means a creel running time of 8100

minutes (Tsble 29). Refering to the part of Table 28 dealing with 1200 spindle assignment, the break rate is found to be

15 per 100 spindle running hours ( the value corrosponding to 8000 minutes of creel running time, 85% work load and

1.94% pnemafil waste).

TABLE - 28

Pnemafil Waste % Expected for Various

Various End Breakage Rates and Creel Exhaust.

Sitra Norms For Spin. Number of spindle Alloted per tenter : 800

Cleaning Time : 15 minutes per 400 spindles per 8 hours.

End Breaks Per 100 Spindle

Creel Running Work Running Hours

Time(minutes) Load(%) 18 21 24 27

3500 85 1.33 1.68 2.24 3.21

75 1.69 2.36 3.66 6.40

5000 85 1.26 1.57 2.05 2.85

75 1.56 2.12 3.16 5.29

6500 85 1.23 1.52 1.97 2.69

75 1.50 2.02 2.94 4.81

8000 85 1.21 1.49 1.91 2.60

75 1.47 1.96 2.82 4.54

9500 85 1.19 1.47 1.88 2.54

75 1.44 1.92 2.74 4.37

11000 85 1.18 1.46 1.86 2.50

75 1.43 1.89 2.69 4.25

12500 85 1.18 1.44 1.84 2.47

75 1.42 1.87 2.65 4.16

1 The above figures include 0.5 % allowance to cover fly and fluff waste sucked by pneumafil.

2 For creel running time corresponding to various fly frame bobbin contents refer to table 29.

PAGE - 73




Number of spindle Alloted per tenter : 1000





3500 85 1.14 1.49 2.12 3.39

75 1.38 2.02 3.48 7.34

5000 85 1.07 1.38 1.90 2.90

75 1.27 1.80 2.89 5.68

6500 85 1.04 1.33 1.80 2.69

75 1.20 1.70 2.65 4.99

8000 85 1.02 1.30 1.75 2.57

75 1.19 1.64 2.52 4.62

9500 85 1.01 1.28 1.71 2.49

75 1.17 1.60 2.44 4.39

11000 85 1.00 1.26 1.69 2.44

75 1.15 1.58 2.38 4.23

12500 85 0.99 1.25 1.67 2.40

75 1.14 1.56 2.34 4.12












5000 85 1.04 1.43 2.17 3.92

75 1.23 1.90 3.58 8.77

6500 85 1.01 1.36 2.02 3.50

75 1.17 1.76 3.17 7.44

8000 85 0.99 1.32 1.94 3.27

75 1.14 1.69 2.95 6.72

9500 85 0.97 1.30 1.88 3.14

75 1.12 1.64 2.82 6.28

11000 85 0.96 1.28 1.85 3.04

75 1.10 1.61 2.73 5.98

12500 85 0.96 1.27 1.82 2.97

75 1.09 1.58 2.66 5.76



PAGE - 74









5000 85 0.90 1.27 2.02 4.11

75 1.02 1.62 3.30 9.73

6500 85 0.87 1.20 1.86 3.57

75 0.97 1.50 2.86 8.00

8000 85 0.85 1.16 1.77 3.29

75 0.94 1.43 2.64 7.06

9500 85 0.84 1.14 1.72 3.12

75 0.93 1.39 2.51 6.49

11000 85 0.83 1.12 1.68 3.01

75 0.91 1.36 2.42 6.11

12500 85 0.82 1.11 1.66 2.93

75 0.90 1.34 2.36 5.84

15000 85 0.81 1.10 1.62 2.84

75 0.89 1.32 2.28 5.53

17500 85 0.81 1.09 1.60 2.77

75 0.89 1.30 2.24 5.32

Sitra Norms For Spin. 20000 85 0.80 1.08 1.59 2.73

75 0.88 1.29 2.20 5.18










Time(minutes) Load(%) 6 9 12

6500 85 0.99 1.55 3.03

75 1.16 2.17 6.41

8000 85 0.96 1.48 2.79

75 1.12 2.02 5.55

9500 85 0.95 1.44 2.64

75 1.09 1.92 5.05

11000 85 0.93 1.41 2.55

75 1.07 1.86 4.73

12500 85 0.92 1.38 2.48

75 1.05 1.82 4.51

15000 85 0.91 1.36 2.40

75 1.03 1.70 4.26

17500 85 0.90 1.34 2.35

75 1.02 1.73 4.09

20000 85 0.90 1.33 2.31

75 1.01 1.71 3.97



PAGE - 75









6500 85 1.37 3.27 12.77

75 1.85 7.69 22.19

8000 85 1.30 2.91 11.15

75 1.70 6.31 20.53

9500 85 1.25 2.71 10.09

75 1.61 5.54 19.36

11000 85 1.22 2.58 9.37

75 1.56 5.06 18.50

12500 85 1.20 2.48 8.85

75 1.51 4.73 17.84

15000 85 1.18 2.38 8.24

75 1.47 4.38 17.03

17500 85 1.16 2.31 7.82

75 1.43 4.15 16.44

20000 85 1.15 2.26 7.53

75 1.41 4.00 16.01

22500 85 1.14 2.23 7.31

Sitra Norms For Spin. 75 1.39 3.88 15.67

25000 85 1.13 2.20 7.13

75 1.38 3.79 15.40

27500 85 1.12 2.17 7.00

75 1.37 3.72 15.18











8000 85 1.56 4.99 18.34

75 2.29 12.82 26.46

9500 85 1.49 4.44 17.14

75 2.11 11.33 25.45

11000 85 1.44 4.10 16.27

75 2.00 10.29 24.69

12500 85 1.41 3.87 15.60

75 1.92 9.55 24.10

15000 85 1.37 3.62 14.79

75 1.84 8.69 23.37

17500 85 1.34 3.45 14.21

75 1.78 8.11 22.84

20000 85 1.32 3.34 13.78

75 1.74 7.70 22.44

22500 85 1.30 3.26 13.45

75 1.71 7.40 22.12

25000 85 1.29 3.19 13.18

75 1.69 7.17 21.87

27500 85 1.28 3.14 12.97

75 1.67 6.98 21.66



PAGE - 76

TABLE - 29

Creel Running Time ( Minutes ) * in Ring Spining

For Different Creel Bobbin Contents

Count Creel Bobbin Content ( Kg )

1.5 1.3 1 0.75

20s 3000 2600 2000 1500

30s 5000 4300 3300 2500

40s 7400 6400 4900 3700

60s 12100 10500 8100 6100

80s 18200 15800 12100 9100

100s 25300 21900 16900 12600

* rounded off to nearest 100.

1 The above creel running durations correspond to the production rates given in Table 11.

2 For optimium weights of rove which can be maintained on different sizes of fly frames bobbins, refer to

Table 32.

NOTES TO TABLE 30

This table gives achievable production in conventional cone winding machines with mechanical as well as

elctronics yarn clearers for six counts (20s,30s,40s,60s,80s and 100s), three cop contents (55g.,60 g.,and 65 g), two

winding-on-speeds ( 550 mpm and 650 mpm ), two different drum assignments and two breakage rates for each count

and for random servicing.

The production estimated are on the following assumptions.

1 The tenter takes the 5 % of the shift time for personal needs,and during this time the drums assigned to him

are considered to be idle.

Sitra Norms For Spin. 2 In a shift of 8 hours,each drum is cleaned by the tenter for a duration of one minute in counts upto 40s, and for

three-fiurths of a minute in 60s and finer counts. During such cleaning, the drums alloted to the tenter are

considered to be idle.

3 A work load of 85% is considered whereever work opporunity exists. In other cases,the work load will be

lower than 85 %.

TABLE - 30

Achievable Production per Tenter in Conventional Cone

Winding for Different Conditions ( per 8 Hours in Kg. )

Drums End Breaks Winding on speed(mpm)

Count Alloted per One 550 650

per Lakh Meters Cop Content(g) Cop Content(g)

tenter 55 60 65 55 60 65

20 12 106 114 120 107 112 120

24 92 97 103 92 98 101

20s 24 12 105 111 118 104 111 117

24 90 95 99 91 95 99

20 12 86 87 88 97 99 101

24 81 83 84 81 85 88

30s 24 12 96 101 102 97 103 108

24 79 83 86 80 83 87

24 10 80 81 81 92 93 94

20 76 77 78 77 81 84

40s 30 10 94 97 98 94 99 104

20 75 78 82 75 79 81

30 8 68 69 69 78 79 80

16 65 65 66 69 72 75

60s 40 8 85 87 87 85 90 93

16 65 68 71 65 68 70

40 7 67 68 68 77 78 78

14 60 62 64 60 63 64

80s 60 7 74 77 81 73 77 80

14 53 55 57 54 55 57

40 6 55 55 55 63 64 64

12 53 53 54 58 60 61

100s 60 6 71 75 77 72 75 78

12 51 53 55 52 53 55

Light type Face : For Mechanical yarn Clearers ; Bold Type Face : For Electronic yarn Clearers

PAGE - 77

TABLE - 31

Yarn Content per Cop in Ring Spinning

Spindle Lift (L) Yarn Content Per Cop

x Ring Diameter(D) Cotton Man Made Fibre &

( inches ) (g) Blended Yarns (g)

6 x 1 1/2 44 47

6 x 1 5/8 51 55

6 x 1 3/4 60 65

7 x 1 1/2 51 55

7 x 1 5/8 60 65

7 x 1 3/4 70 75

7 x 1 7/8 80 86

8 x 1 5/8 69 75

8 x 1 3/4 80 86

8 x 1 7/8 91 99

8 x 2 104 112

8 x 2 1/4 132 142

8 x 2 1/2 162 175

1 The cotton yarn content per cop for a given spindle lift and ring diameter is nearly equal to :

3.25 x L x D2 grams.

2 The yarn content for man made fibre and blended yarns are roughly 8% more than those for cotton yarns

for comparable spindle lifts and ring diameters.

sitra norms for spinning mills sitra norms for spin.€¦ · sitra norms for spin. page no - 4...

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