Post on 19-Nov-2020
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.
Page 1
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.
Page 2
Sitra Norms For Spin.
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.
Page 3
Sitra Norms For Spin.
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 4
Sitra Norms For Spin.
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 5
Sitra Norms For Spin.
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 6
Sitra Norms For Spin.
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 7
Sitra Norms For Spin.
PAGE No - 4
TABLE - 4 ( Contd.)
Fibre Properties of Some Indian Cottons
( Measured by Conventional Testing Instruments )
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 8
Sitra Norms For Spin.
PAGE No - 5 TABLE - 4 ( Contd.)
Fibre Properties of Some Indian Cottons
( Measured by Conventional Testing Instruments )
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 9
Sitra Norms For Spin.
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 10
Sitra Norms For Spin.
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
NORMS FOR FIBRE PROPERTIES TO SPIN YARNS
WITH 3 DIFFERENT LEVELS OF csp
UNDER GOOD WORKING CONDITION
( Fibre properties measured by HVI Test System)
(Finer 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 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 11
Sitra Norms For Spin.
PAGE No - 8
TABLE - 6 ( Contd.)
NORMS FOR FIBRE PROPERTIES TO SPIN YARNS
WITH 3 DIFFERENT LEVELS OF csp
UNDER GOOD WORKING CONDITION
( Fibre properties measured by HVI Test System)
(Finer 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)
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 12
Sitra Norms For Spin.
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 13
Sitra Norms For Spin.
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
Page 14
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
Page 15
Sitra Norms For Spin. 11.5 15.7 0.90 4.4
PAGE No - 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 )
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 16
Sitra Norms For Spin.
PAGE No - 13
TABLE - 12
Norms for Fibre Properties to Spin Yarns With 3 Different
Levels of U % Under Good Working Conditions
( Fibre Properties Measured by HVI Test System )
( Finer Fibres )
Count Yarn 50 % Span Maturity Micronaire Values
( Ne ) U % Length (mm ) Ratio ( ug / inch )
( 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 17
Sitra Norms For Spin.
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
Page 18
Sitra Norms For Spin.
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 .
Page 19
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 20
Sitra Norms For Spin.
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
Page 21
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 22
Sitra Norms For Spin.
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
Page 23
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
Page 24
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 licker- in 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 25
Sitra Norms For Spin.
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
Page 26
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 ( % )
Page 27
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
Page 28
Sitra Norms For Spin.
High Speed 20 10
PAGE No - 25 TABLE - 43
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 29
Sitra Norms For Spin.
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
Page 30
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
Page 31
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
Page 32
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
Page 33
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
Page 34
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. )
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 )
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
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 )
( Finer 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 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
Page 35
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 . )
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 )
( Finer Fibres )
Count RKM Value 50 % Span Fibre Micronaire
of Yarn Length Strength Value
( g / tex ) ( mm ) ( g / tex ) ( g / inch )
( 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
Page 36
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
Page 37
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 38
Sitra Norms For Spin.
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
Page 39
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
Page 40
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
Page 41
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
Page 42
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 (%)**
Page 43
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
Page 44
Sitra Norms For Spin.
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 .
PAGE No - 41 TABLE - 86
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
Page 45
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
Page 46
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
Page 47
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.
PAGE No - 44 TABLE - 98
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
Page 48
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 %
PAGE No - 45 TABLE - 102
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
Page 49
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
Page 50
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
Page 51
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
Page 52
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.
PAGE No - 49 TABLE - 112
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 %
Page 53
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
PAGE No - 50 TABLE - 117
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
Page 54
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
Page 55
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
Page 56
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
Page 57
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
Page 58
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.
Page 59
Sitra Norms For Spin. TABLE - 7
Production Rates,Sliver hank.Front Rollar Speed & Machine Efficiency
Super High-speed Draw Frames - carded counts
(Single Delivery Machine with Auto-Leveller)
Front Production per
Count Roller Sliver Machine Delivery per
Group Speed Hank Effiency 8 hours
(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
1. Footnotes to table 5 hold good for this table also
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
Production Rates,Sliver hank.Front Rollar Speed & Machine Efficiency
Super High Speed Draw frames - Combed counts
(Single Delivery Machine with Auto-Leveller)
Front Production per
Count Roller Sliver Machine Delivery per
Group Speed Hank Effiency 8 hours
(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
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
Page 60
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
Page 61
Sitra Norms For Spin. TABLE - 10
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-
Page 62
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.)
Production per Spindle,Spindle Speeds,Twist Multiplier,
TPI and Machine Efficiency
Ring Frame - Carded Counts.
Spindle Twist* TPI Machine Production * *
Count Speed Multiplier Efficiency per Spindle
(rpm) (%) per 8 Hours
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
Page 63
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
Production per Spindle,Spindle Speeds,Twist Multiplier,
TPI and Machine Efficiency
Ring Frame - Combed Counts. And Polyester Blends
Spindle Twist* TPI Machine Production * *
Count Speed Multiplier Efficiency per Spindle
(rpm) (%) per 8 Hours
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
Page 64
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
** Production per spindle = 7.2 * Spindle Speed * Machine Efficiency
per 8 Hours (g.) Tpi * Count 100
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.
Page 65
Sitra Norms For Spin. TABLE - 15
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
** Production per spindle = 7.2 * Spindle Speed * Machine Efficiency
per 8 Hours (g.) Tpi * Count 100
PAGE - 63 TABLE - 16
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%
Page 66
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.
PAGE - 64 TABLE - 17
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
Page 67
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
Page 68
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
Page 69
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)
PAGE - 67 TABLE - 21
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
Page 70
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.
Page 71
Sitra Norms For Spin.
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
Page 72
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
Page 73
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
Page 74
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.
Page 75
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
TABLE - 28 ( Contd.)
Pnemafil Waste % Expected for Various
Various End Breakage Rates and Creel Exhaust.
Number of spindle Alloted per tenter : 1000
Cleaning Time : 15 minutes per 400 spindles per 8 hours.
End Breaks Per 100 Spindle
Creel Running Work Running Hours
Time(minutes) Load(%) 12 15 18 21
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
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 76
Sitra Norms For Spin.
TABLE - 28 ( Contd.)
Pnemafil Waste % Expected for Various
Various End Breakage Rates and Creel Exhaust.
Number of spindle Alloted per tenter : 1200
Cleaning Time : 15 minutes per 400 spindles per 8 hours.
End Breaks Per 100 Spindle
Creel Running Work Running Hours
Time(minutes) Load(%) 9 12 15 18
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
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 - 74
TABLE - 28 ( Contd.)
Pnemafil Waste % Expected for Various
Various End Breakage Rates and Creel Exhaust.
Number of spindle Alloted per tenter : 1400
Cleaning Time : 15 minutes per 400 spindles per 8 hours.
End Breaks Per 100 Spindle
Creel Running Work Running Hours
Time(minutes) Load(%) 6 9 12 15
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
Page 77
Sitra Norms For Spin. 20000 85 0.80 1.08 1.59 2.73
75 0.88 1.29 2.20 5.18
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.
TABLE - 28 ( Contd.)
Pnemafil Waste % Expected for Various
Various End Breakage Rates and Creel Exhaust.
Number of spindle Alloted per tenter : 1600
Cleaning Time : 15 minutes per 400 spindles per 8 hours.
End Breaks Per 100 Spindle
Creel Running Work Running Hours
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
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 - 75
TABLE - 28 ( Contd.)
Pnemafil Waste % Expected for Various
Various End Breakage Rates and Creel Exhaust.
Number of spindle Alloted per tenter : 2000
Cleaning Time : 15 minutes per 400 spindles per 8 hours.
End Breaks Per 100 Spindle
Creel Running Work Running Hours
Time(minutes) Load(%) 6 9 12
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
Page 78
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
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.
TABLE - 28 ( Contd.)
Pnemafil Waste % Expected for Various
Various End Breakage Rates and Creel Exhaust.
Number of spindle Alloted per tenter : 2200
Cleaning Time : 15 minutes per 400 spindles per 8 hours.
End Breaks Per 100 Spindle
Creel Running Work Running Hours
Time(minutes) Load(%) 6 9 12
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
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 - 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.
Page 79
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.
Page 80