Combing Behaviors at Different Parameters

Combing behaviors at different parameters 2013

Produced By Mr. Sunil Kumar Sharma, Published in Spinning Textiles Magazine, Vol.7, Issue-5, Sept.-Oct. 2013 Edition. Page 1

Abstract : - Combing is a very important process for a spinning mill. The object of

combing is removal of short fibres, Neps, impurities and to improve the fibre length

uniformity followed with improvement in mean length. The removal of immature

cotton, foreign matter and improvement in fibre fineness and fibre bundle strength are

the additional advantages of combing process. In totality combing process

significantly improves the cotton characteristics by removing the useless fibres (i.e.

Fibres which are not suitable for a particular end use) from the process. These fibres

are extracted as comber Noil waste. This Complete combing process carried out by

action of different combing elements. During combing process along with useless

fibres good quality fibres are also removed especially in modern high speed combers

which are huge raw material & financial losses for the industry. We have studied in

detail the combing action of these different combing elements w.r.t. removal of Neps,

SFC % & other impurities with mean length improvement. The object of this article is

to present the effect of different combing elements on cotton processed and how we

can perfectly set these combing elements to get the better combing process with

respect to desire Quality, so we can achieve maximum removal of useless fibres with

minimum losses of good fibres. Keywords : Comber, Combing elements, Top Comb, Top comb penetration, Top comb penetration

depth, Feed/Nips, Nips/Minutes, Lap batt, Sliver, Noil, Unicomb, Afis Pro, Imperfection,

classimat faults.

Abbreviations : - SCN = Seed coat Neps, um = Microns, MR = Maturity Ratio, IFC=Immature

Fibre Content, SFC = Short fibre Content, IPI – Imperfection, CMT=Classimat, TC = Top comb,

UQL=Upper Quartile Length, L(w) = Length by weight, L (n) = Length by number, FD = Foreign

Dark.

Methodology : - To study the combing action of different combing elements, we have

selected unique set of back process with constant process parameters. Following

process flow & machineries have been used for study purpose : - Table : - 1.0 : Process Flow & Machinery set up being used for Studies. Sr. No. Process Flow & Machinery Set up

1. Modern Blow Room line with automatic feeding. 2. Very High production Card’s with autoleveller.



3. Moder high speed Br. Draw Frames 4. Moder high production Lap Former 5. Moder High speed Combers. 6. Fin. Draw Frames 7. Roving Frames 8. Ring frames with pneumatic drafting. 9. Modern Autoconer with optical EYC clearer.

For each study we produced total 32 No. of laps with same back stuff and tested all

laps for fibre length distribution & neps at AFIS – Pro2. There after we have

conducted four no. of trials with each set of laps (i.e. creel on 8 No. of comber

Head’s) at same comber keeping all other parameters constant.

Following combing parameters have been selected for study and four no. of trials has

been conducted for each combing parameter. Comber Lap, Sliver & Noil waste

analyzed for fibre length distribution & Neps analysis for each trial. All studies &

trials conducted at same set of combing process & process parameters.

1. Study -1 : Different Top Comb Penetration by keeping same parameters.

2. Study – 2 : Different Top comb Penetration at same comber noil %.

3. Study – 3 : Different amount of feed per cycle i.e. 4.3, 4.7, 5.2, & 5.9 mm

4. Study – 4 : Different lap batt weight Gms / Mtrs.

5. Study – 5 : Different Combing Speed i.e. Nips / Minutes.

6. Study – 6 : Type of Feed i.e. Forward vs Backward Feed.

Study – 1 : - Top Comb Penetration depth : The aim of setting the top comb penetration depth is to

extract the husk, seed coats, neps and other impurities from combing fleece.

Study -1 conducted with different top comb penetration in sequence of – 0.5 mm to +

1.0 mm with an increment of 0.5 mm by keeping all others parameters unchanged. Table : - 1.1 : Combing Process & Process Parameters.

Lap Parameters Gms / Mtrs. 74.0 No. of Doubling at Unilap 20 Total Unilap Draft 1.59 Comber Parameters Feed Forward Feed



Feed / Nips 5.2 Nips / Minutes 500 Waste Index 8.0 Changeable Parameter Top Comb Penetration.

Table – 1.2 : Neps Analysis for Lap, Combed Sliver & Comber Noil Waste at different Top comb penetration.

Unilap Total Neps 139

Total Neps Size 643

Fibre Neps 134.5

Fibre Neps size 643

SCN 7.5

SCN Size 946.5

Neps size distribution

Neps size 450 - 750 um 85.8

Neps size 751 - 1050 um 11.65

Neps size above 1051 um 2.25 Comber

Top Comb Penetration depth (in mm) -0.5 0.0 +0.5 +1.0

Noil % 13.87 15.81 17.83 19.33

Total Neps 71 52 55 44

Total Neps Size 623 629 628 627 Fibre Neps 69.0 50.0 54.0 42.0 Fibre Neps size 615.0 617.0 622 618 SCN 2.0 2.0 1.0 1.0 SCN Size Neps Removal efficiency %

891 48.9

941 62.6

935 60.4

920 68.3

Neps size distribution in Combed Sliver

Neps size 450 - 750 um 89.8 88.4 87.7 88.1

Neps size 750 - 1050 um 9.6 10.8 12.3 11.0 Neps size 1050 - 1500 um 0.3 0.4 0.4 0.4

Analysis of Noil Waste Total Neps 694 739 568 638 Total Neps Size 679 668 669 675 Fibre Neps 639 697 527 600 Fibre Neps size 650 650 648 653 SCN 56 42 41 38 SCN Size 1024 949 940 1003

Neps size distribution in Noil Waste

Neps size 450 - 750 um 79.4 81.0 81.4 81.1 Neps size 750 - 1050 um 15.3 15.5 14.4 14.4 Neps size 1050 - 1500 um 4.1 3.0 3.9 4.0

Combing behaviors at different parameters

Produced By Mr. Sunil Kumar Sharma, Published in Spinning Textiles Magazine, Vol.7, Issue

Fig. – 1.1 : Graphical representation of

Fig. – 1.2 : Graphical representation of Neps size d

Observations : -

13.9

71

48.9

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

-0.5

Noil %

-0.5 0.0

89.8

9.6

0.3

Neps size 1050 - 1500 um


Vol.7, Issue-5, Sept.-Oct. 2013 Edition.

Graphical representation of Noil % & Combed Sliver Neps at different Top Comb Penetration

Graphical representation of Neps size distribution in Combed Sliver at different TC penetration

15.817.8 19.3

5255

62.6 60.4

0.0 +0.5

Total Neps/ Gms Neps Removal Eff. %

0.0 +0.5 +1.0

88.4 87.7 88.1

10.8 12.3 11.0

0.4 0.4 0.4

1500 um Neps size 750 - 1050 um Neps Size 450


Page 4

Sliver Neps at different Top Comb Penetration.

at different TC penetration.

19.3

44

68.3

+1.0

Neps Removal Eff. %

Neps Size 450 - 750 um



1. Noil % increases with increase in top comb penetration depth i.e. – 0.5mm to +

1.0mm, subsequently Neps removal efficiency increases significantly. Ref. fig.

1.1

2. There is no significant change observed in neps size of combed sliver with

different TC settings, similarly there is no trend observe in fibre characteristics

of noil extracted at different TC settings. Ref. fig. 1.2

3. It is quite surprise that neps size is not much affected by top comb penetration.

Even bigger neps sizes i.e. above 1000 um were also not affected by increasing

the top com penetration. Ref. fig. 1.2

Table – 1.3 : Fibre Length Distribution for Lap, Combed Sliver & Noil Waste at different Top Comb Penetration.

Unilap UQL (W) mm 31.7

L (w) CV % 36.5

SFC (W) % 8.6

SFC (n) % 25.3

5 % Spun Length (n) mm 36.6

Micronaire

Maturity Ratio

Immature Fibre Content

3.90

0.88

7.75

Fibre Length distribution in %

less than 12.0 mm 24.4

13.0 to 20.0 mm 23.6

21.0 to 30.0 mm 32.9

Above 31.0 mm 17.6 Combed Sliver

Top Comb Penetration depth (in mm) -0.5 0.0 + 0.5 + 1.0

Noil % 13.87 15.81 17.83 19.33

UQL (W) mm 32.3 31.9 32.1 32.0

L (w) CV % 35.0 35.6 34.4 35.4

SFC (W) % 5.5 5.7 5.0 5.2

SFC (n) % 15.3 15.6 13.5 13.9

5 % Spun Length (n) mm Micronaire

Maturity Ratio


37.7 4.06

0.92

5.8

37.4 4.06

0.91

5.7

37.6 4.09

0.92

5.3

37.7 4.09

0.93

5.3


less than 12.0 mm 15.4 15.6 13.5 15.0



13.0 to 20.0 mm 27.0 28.4 27.8 30.0

21.0 to 30.0 mm 36.1 35.9 37.4 34.9

Above 31.0 mm 19.6 17.9 19.3 13.4

Analysis of Noil Waste UQL (W) mm 16.0 15.3 15.4 16.3

SFC (W) % 57.6 59.8 59.4 55.8

SFC (n) % 79.5 80.8 80.1 78.0

5 % Spun Length (n) mm Micronaire

Maturity Ratio


19.7 3.40 0.68 20.3

18.9 3.43 0.67 20.8

19.2 3.40 0.68 20.1

20.3 3.43 0.68 19.2


less than 12.0 mm 79.5 80.9 80.2 77.9

13.0 to 20.0 mm 15.8 15.3 15.4 16.9

21.0 to 30.0 mm 0.3 3.5 3.6 4.4

Above 31.0 mm 0.5 0.6 0.6 0.8

Fig. 1.3 : Graphical representation of Noil Waste, UQL (mm), SFC % & Length CV % at different top

comb penetration.

Fig. 1.4 : Graphical representation of Fibre length distribution in Combed sliver.

13.8715.81

17.8319.33

32.3 31.9 32.1 32.0

15.3 15.6

13.513.9

35.0 35.634.4 35.4

10

15

20

25

30

35

40

-0.5 0.0 + 0.5 + 1.0

Noil %

UQL (mm)

SFC (n) %

L (w) CV %



Fig. 1.5 : Graphical Representation of Fibre Length distribution in Comber Noil Waste.

Observations : -

-0.5

15.4

27.0

36.1

19.6

Fibre Length above 31 mm

Fibre Length 13 to 20 mm.

-0.5

79.5 80.9

15.8

0.3 0.5

Fibre Length below 12 mm.

Fibre Length 21 to 30 mm



5 : Graphical Representation of Fibre Length distribution in Comber Noil Waste.

0.0 + 0.5 + 1.0

15.6 13.5 15.0

28.4 27.8 30.0

35.9 37.434.9

17.9 19.3 13.4

Fibre Length above 31 mm Fibre Length 21 to 30 mm

Fibre Length 13 to 20 mm. Less than 12 mm i.e. SFC %

0.0+ 0.5

+ 1.0

80.980.2

77.9

15.315.4

16.93.53.6

4.4

0.60.6

0.8

Fibre Length below 12 mm. Fibre Length 13 to 20 mm.

Fibre Length 21 to 30 mm Fibre Length above 31 mm


Page 7

5 : Graphical Representation of Fibre Length distribution in Comber Noil Waste.

Fibre Length 21 to 30 mm

Less than 12 mm i.e. SFC %

0.8

Fibre Length 13 to 20 mm.




1. There are no significant difference observed in fibre length UQL, length CV %,

SFC % & 5 % spun length at different top comb penetration even with significant

increase in comber Noil %. Refer Fig. 1.3

2. Fibre length above 21.0 mm significantly reduces in combed sliver with + 1.0 mm

top comb penetration as compared with lower TC penetration depth. Same thing

confirmed through comber Noil analysis, where fibre length more than 21.0 mm

observed high with + 1.0 mm TC penetration as compare to lower TC penetration.

This might be due to significant difference in Noil %. Refer Fig. 1.4 & 1.5

3. It has been observed that lower micronaire & immature fibres significantly

removed after combing and goes with comber noil waste. However there is no

trend observed with respect to change in top comb penetration. Table – 1.4 : Yarn Results at different Top comb penetration with different Noil %. Comber T.C. Penetration (in mm) -0.5 0.0 +0.5 +1.0

Comber Noil % 13.9 15.8 17.8 19.3

Finisher Draw Frame U % 1.85 1.81 1.75 1.68

Ring Yarn Results

U % 9.31 9.07 8.76 8.65

Thin (-50%) 0.3 0.1 0.0 0.0

Thick (+50%) 25.9 22.3 15.6 9.6

Neps (+200%) 110.5 85.3 56.7 41.9

Total 137 108 72 52

Hairiness 5.25 5.20 5.09 5.55

Sh 1.05 1.00 1.01 1.04

FD /KM 1.90 1.75 1.75 1.00

Veg/Km 1.05 1.20 1.20 0.45

RKM 17.2 17.9 17.7 17.9

RKM CV% 6.80 6.50 6.70 6.50

Elong. 4.06 3.79 4.00 3.95

Elong CV% 10.10 9.60 11.10 8.70

Classimat - Cop /100 KM Objectionable Faults - Short Class

(A4+B4+B3+C4+C3+C2+D4+D3+D2+D1) 23.0 16.0 12.0 15.0 Long faults - ( E+F+G) 8.0 12.0 7.0 7.0 Long thin faults ( I1+I2) 0.0 0.0 0.0 0.0 Thin faults ( H1+H2) 0.0 0.0 0.0 0.0 Remaining short faults (A3+B2+C1) 14.0 10.0 8.0 12.0 Raw material faults (A1+A2+B1) 68.9 72.0 77.0 94.0



Total faults all classes 114 110 104 128

Clearer Cuts / 100 KM

Total Cuts 52 36 57 47

Neps Cuts 0 0 0 0

Short Cuts 16 18 31 19

Long Cuts 8 8 11 12

Thin Cuts 4 3 1 2

Foreign fibre Cuts 16 9 10 12

Off Count Cuts 1 0 0 0

Fig. 1.6 : Graphical Representation of Total Yarn imperfection, U % & Noil % at different top comb

penetration.

Fig. 1.7 : Graphical Representation of Total CMT Faults, clearer cuts & RKM at different top comb

penetration.

137

108

72

52

13.9 15.8 17.8 19.39.31 9.07 8.76 8.65

1.85 1.81 1.75 1.68

-0.5 0.0 +0.5 +1.0

Tot. Imp. Noil % U % FDF U %



Observations : -

1. Yarn U % & imperfection reduces significantly with increase in top comb

penetration with increase in comber

2. There is no trend observed for

deferent TC penetration. Ref. fig. 1.

Study – 2 : - Different Top comb penetration at same comber Noil %

Study -2 conducted with different top comb penetration in sequence of

1.0 mm with an increment of 0.5 mm

all others parameters unchanged. Table : - 2.1 : Combing Process & Process Parameters.

Lap Parameters Gms / Mtrs. No. of Doubling at Unilap Total Unilap Draft Comber Parameters Feed Feed / Nips Nips / Minutes Waste Index Changeable Parameter

-0.5

114 110

52

17.2

Total CMT Faults / 100 Km.



Yarn U % & imperfection reduces significantly with increase in top comb

penetration with increase in comber noil %. Ref. fig. 1.6

There is no trend observed for classimat faults, clearer cuts & yarn RKM with

Ref. fig. 1.7

Different Top comb penetration at same comber Noil %

2 conducted with different top comb penetration in sequence of

1.0 mm with an increment of 0.5 mm by maintaining the same Noil % with

all others parameters unchanged. 1 : Combing Process & Process Parameters.

74.0 20 1.59 Forward Feed 5.2 500 Adjustable to set the 19.5 % Noil. Top Comb Penetration.

0.0 +0.5 +1.0

110104

128

36

57

17.9 17.7

Total CMT Faults / 100 Km. Clearer Cuts / 100 Km. RKM


Page 10

Yarn U % & imperfection reduces significantly with increase in top comb

classimat faults, clearer cuts & yarn RKM with

Different Top comb penetration at same comber Noil %

2 conducted with different top comb penetration in sequence of – 0.5 mm to +

by maintaining the same Noil % with keeping

+1.0

47

17.9

RKM



Table – 2.2 : Fibre Length Distribution for Lap, Combed Sliver & Noil Waste at different Top Comb Penetration. Top Comb Penetration (mm) - 0.5 0.0 + 0.5 + 1.0

Noil% 19.5 19.5 19.3 19.4

Unilap

Total Neps 161

Total Neps Size 653.5

Fibre Neps 151.5

Fibre Neps size 632

SCN 9

SCN size 1040

Neps Size Distribution Neps Size 450 - 750 um 83.4

Neps Size 751 - 1050 um 13.0

Neps Size above 1051 um 3.2

Length Analysis UQL(W) 31.55

SFC(W)% 8.9

SFC(n)% 26.05

5%L(n) 36.5

Length Distribution in %

Less than 12.0 mm. 26.0

13.0 to 20.0 mm. 24.0

21.0 to 30.0 mm 32.5

Above 31.0 mm 16.0

Micronaire 3.82

MR 0.86

IFC% 8.5

Comber Sliver


Neps Removal Efficiency % 45.3 43.5 62.7 70.2

Total Neps Size 628 625 642 640

Fibre Neps 86.0 89.0 57.0 47.0

Fibre Neps size 619.0 613.0 628 627

SCN 2.0 2.0 2.0 1.0

SCN size 946 1124 989 1119

Neps Size Distribution Neps Size 450 - 750 um 87.9 90.8 86.3 87.1

Neps Size 751 - 1050 um 10.6 8.0 11.6 10.1

Neps Size above 1051 um 1.1 1.0 1.8 2.0

Length Analysis



UQL(W) 31.7 31.9 32.0 31.9

SFC(W)% 5.2 5.4 4.6 4.9

SFC(n)% 14.4 14.8 12.7 13.5

5%L(n) 37.7 37.8 37.6 37.7


Less than 12.0 mm. 14.4 14.6 12.7 13.5

13.0 to 20.0 mm. 29.7 29.5 28.8 28.8

21.0 to 30.0 mm 36.9 36.2 37.9 37.5

Above 31.0 mm 16.7 17.0 18.3 18.0

Micronaire 4.04 4.04 4.04 4.06

MR 0.91 0.91 0.92 0.92

IFC% 6.0 6.3 5.7 5.6

Noil Waste

Total Neps 825 732 722 750


Fibre Neps 779 685 684 709

Fibre Neps size 653 653 649 654

SCN 46 46 38 41

SCN size 1032 1012 988 1061


Neps Size 751 - 1050 um 15.2 15.9 15.2 13.9


Length Analysis UQL(W) 16.5 16.4 16.4 15.8

SFC(W)% 53 53.2 54.3 56.9

SFC(n)% 75.5 75.6 76.6 78.6

5%L(n) 20.3 20.5 20.3 19.4


Less than 12.0 mm. 75.6 75.7 76.5 78.6

13.0 to 20.0 mm. 19.3 18.9 18.1 17.0

Above 21.0 mm 5.3 5.4 5.3 4.3

Micronaire 3.43 3.40 3.38 3.45

MR 0.68 0.68 0.68 0.66

IFC% 20.1 19.3 19.9 21.7

Fig. 2.1 : Graphical representation of Combed Sliver Neps/Gm, UQL (mm), SFC (n) % & NRE % at different top

comb penetration.



Observations : -

1. Neps removal efficiency increases significantly with increase in top comb

penetration even by maintaining the same Noil level. SFC % not much affected

with top comb penetration however there also slight reduction observed with

higher TC penetration depth. Ref. Fig. 3.1

2. Upper Quartile mean length observed almost same in all studies. Ref. Fig. 3.1

3. There is no remarkable trend observed with any other Quality parameters.

Table – 2.2 : Yarn Results at different Top comb penetration with different Noil %.

Top Comb Penetration (mm) - 0.5 0.0 + 0.5 + 1.0

Noil% 19.5 19.5 19.3 19.4


U% 8.74 8.78 8.69 8.59

Thin (-50%) 0.0 0.0 0.0 0.0

Thick (+50%) 13.7 12.7 10.9 8.9

Neps (+200%) 80.0 68.5 53.0 34.3

Total 93.7 81.2 63.9 43.2

Hairiness 5.15 5.04 5.11 5.23

Sh 0.99 0.98 1.00 1.02

FD /KM 3.35 2.15 2.40 0.90

Veg/Km 1.95 0.80 1.30 0.45

8891

60

48

31.7 31.9 32.031.9

14.4 14.8 12.713.5

45.343.5

62.7

70.2

0

10

20

30

40

50

60

70

80

90

100

- 0.5 0.0 + 0.5 + 1.0

Neps / Gms

UQL (mm)

SFC (n) %

NRE %

Top Comb Penetration (mm)



RKM

RKM CV%

Elong.

Elong CV%

Classimat - Cops (/100 KM) Objectionable Faults - Short Class

(A4+B4+B3+C4+C3+C2+D4+D3+D2+D1) Long faults - ( E+F+G)

Long thin faults ( I1+I2)

Thin faults ( H1+H2)

Remaining short faults (A3+B2+C1)

Raw material faults (A1+A2+B1)

Total faults

Clearer Cuts/100Km

Total Cuts

Neps Cuts

Short Cuts

Long Cuts

Thin Cuts

Foreign fibre Cuts

Off Count Cuts

Fig. 2.2 : Graphical Representation of Yarn imperfection, Total CMT Faults,

93.7

81.2

95

105

47

18.2

0.0

20.0

40.0

60.0

80.0

100.0

120.0

140.0

- 0.5



18.2 19.0 19.2

6.20 6.80 6.70

4.20 4.60 4.65

10.40 10.20 7.60

14.0 17.0 16.0

2.0 9.0 20.0

0.0 0.0 0.0

0.0 0.0 0.0

4.0 9.0 8.0

75.2 39.5 43.0

95 105 87

47 40 41

0 1 3

25 21 25

6 4 6

2 1 1

15 7 1

0 1 0

Graphical Representation of Yarn imperfection, Total CMT Faults, Clearer Cuts & Yarn RKM.

81.2

63.9

43.2

105

87

126

40 41

56

19.0 19.1 19.2

0.0 + 0.5 + 1.0

Yarn Imperfection

Total CMT Faults

Total Clearer Cuts / 100 km.

Yarn RKM


Page 14

19.2

5.70

4.84

5.80

22.0

18.0

0.0

0.0

17.0

69.0

126

56

0

26

12

1

4

0

Cuts & Yarn RKM.

Yarn Imperfection

Total CMT Faults

Total Clearer Cuts / 100 km.

Yarn RKM



Observations : -

1. Yarn U % & imperfection reduces significantly with increase in top comb depth.

Yarn RKM & elongation % also improves marginally with increase in TC depth.

However yarn hairiness observed slightly high at + 1.0 mm top comb

penetration. Ref. fig. 2.2

2. Total classimat faults and clearer cuts observed high at + 1.0 mm TC

penetration, while it’s observed comfortable level at + 0.5 mm TC penetration. Ref. fig. 2.2

Study – 3 : - Feed amount moved per cycle (i.e. Feed per Nips) considerably change

the production rate & quality of combing output.

Study conducted by changing the comber Feed per nips in order of 4.3, 4.7, 5.2 & 5.9

mm with all others parameters unchanged. Table : - 3.1 : Combing Process & Process Parameters.

Lap Parameters Gms / Mtrs. 74.0 No. of Doubling at Unilap 20 Total Unilap Draft 1.59 Comber Parameters Feed Forward Feed Nips / Minutes 500 Top Comb Penetration. + 1.0 mm Waste Index 8.0 Changeable Parameter Feed / Nips in order to 4.3 / 4.7 / 5.2 / 5.9 mm per Nips

Table – 3.2 : Detail Fibre Analysis of Lap, Combed Sliver & Comber Noil Waste at different Feed / Nip. Comber Feed/Nip 4.3 4.7 5.2 5.9

Noil% 19.8 19.3 19.5 18.6

Unilap

Total Neps 139 Total Neps Size 648 Fibre Neps 131 Fibre Neps size 632 SCN 8 SCN size 911

Neps Size Distribution Neps Size 450 - 750 um 84.3 Neps Size 751 - 1050 um 12.9 Neps Size above 1051 um 2.7

Length Analysis



UQL(W) 26.00 SFC(W)% 7.7 SFC(n)% 23.05 5%L(n) 37.0


Less than 12.0 mm. 23.1 13.0 to 20.0 mm. 23.2 21.0 to 30.0 mm 33.8 Above 31.0 mm 18.3

Micronaire 3.92 MR 0.89 IFC% 7.2

Comber Sliver

Total Neps 53 58 48 61 Total Neps Size 634 621 605 622 Fibre Neps 51 57 48 60 Fibre Neps size 625 612 604 613 SCN 2 1 0 1 SCN size 926 1029 800 984

Neps Size Distribution Neps Size 450 - 750 um 87.6 90.4 84.9 81.7 Neps Size 751 - 1050 um 10.3 7.4 13.8 14.0 Neps Size above 1051 um 2.0 1.8 1.1 3.6

Length Analysis UQL(W) 31.9 31.7 32.0 31.8 SFC(W)% 5.4 5.8 4.4 6.0 SFC(n)% 14.4 15.3 12.0 16.0 5%L(n) 37.7 37.7 37.4 37.5


Less than 12.0 mm. 14.4 15.3 12.0 15.9 13.0 to 20.0 mm. 30.0 30.2 27.7 29.5 21.0 to 30.0 mm 36.0 35.6 38.9 35.3 Above 31.0 mm 17.1 16.7 19.6 17.2

Micronaire 4.09 4.09 4.06 4.09 MR 0.91 0.91 0.92 0.91 IFC% 5.8 5.8 5.5 6.0

Noil Waste

Total Neps 583 778 662 811 Total Neps Size 675 665 672 669 Fibre Neps 541 736 617 763 Fibre Neps size 647 644 652 645 SCN 41 42 46 48 SCN size 1041 1026 947 1039

Neps Size Distribution Neps Size 450 - 750 um 81.3 82.2 80.8 81.7 Neps Size 751 - 1050 um 13.9 11.4 15.4 14.0 Neps Size above 1051 um 3.8 2.4 3.3 3.6




SFC(W)% 60.3 60.0 57.8 57.8 SFC(n)% 80.7 80.8 79.1 79.5 5%L(n) 18.7 18.9 19.6 19.4


Less than 12.0 mm. 80.7 80.9 79.1 79.5 13.0 to 20.0 mm. 15.5 15.0 16.3 16.1 Above 21.0 mm 0.8 4.1 4.6 4.3

Micronaire 3.50 3.48 3.43 3.48 MR 0.66 0.66 0.68 0.66 IFC% 21.7 21.2 19.7 21.0

Fig. 3.1 : Graphical Representation of Noil %, Neps/Gms, SFC (n) % & UQL of Combed Sliver at different Feed /

Nip.

19.8 19.3 19.5 18.6

5358

48

61

14.4 15.312.0

16.0

31.9 31.7 32.0 31.8

4.3 4.7 5.2 5.9

Noil % Neps/Gms SFC (n) % UQL (mm)

Feed / Nip



Fig. 3.2 : Graphical Representation of


Observations : -

1. There is no trend observed for Noil %, Combed Sliver Neps & SFC % and in

length improvement with increase in comber feed / Nip.

4.3

87.6

10.3

2.0

Neps Size above 1051 um

4.3

80.7

15.5

0.8

Fibre Length < 12.0 mm (SFC)



: Graphical Representation of Neps size distribution of Combed Sliver at different Feed / Nip.

: Graphical Representation of Fibre Length distribution of Noil Waste at different Feed / Nip.

is no trend observed for Noil %, Combed Sliver Neps & SFC % and in

length improvement with increase in comber feed / Nip. Ref. Fig.

4.7 5.2 5.9

90.4 84.9 81.7

7.4 13.8 14.0

1.8 1.1

Neps Size above 1051 um Neps size 751 - 1050 um Neps size 450

Feed / Nip

4.7 5.2

80.9 79.1 79.5

15.0 16.3

4.1 4.6

Fibre Length < 12.0 mm (SFC) Fibre Length 13 - 20 mm Fibre Length above 21 mm

Feed/Nip


Page 18

of Combed Sliver at different Feed / Nip.

at different Feed / Nip.

is no trend observed for Noil %, Combed Sliver Neps & SFC % and in

Ref. Fig.-3.1

81.7

14.0

3.6

Neps size 450 - 750 um

5.9

79.5

16.1

4.3




2. Noil waste reduces at significant increase in feed amount per nip (i.e. 5.9), while

higher noil extracted at lower feed/nip. Ref. Fig.-3.1

3. Neps size above 751 um removed more at lower Feed/Nip (i.e. 4.3 & 4.7) as

compared to higher Feed/Nip (i.e. 5.2 & 5.9). Ref. Fig.-3.2

4. Similarly better short fibre removal & less rich fibre extraction observed at

lower Feed/Nip as compared to higher Feed/Nip. Ref. Fig.-3.3

Table – 3.3 : Yarn Results at different amount of feed per nips. Comber Feed/Nip 4.3 4.7 5.2 5.9

Noil % 19.8 19.3 19.5 18.6


U% 8.85 8.73 8.89 9.00 Thin (-50%) 0.4 0.0 0.1 0.0

Thick (+50%) 8.2 10.6 13.1 16.1

Neps (+200%) 31.4 37.8 43.7 57.3

Total 40.0 48.4 56.9 73.4 Hairiness 5.02 4.98 5.03 5.01 Sh 0.96 0.96 0.98 0.98

FD /KM 1.10 1.40 1.05 1.45

Veg/Km 0.50 0.85 0.65 1.00

RKM 17.64 18.78 17.64 18.17

RKM CV% 7.10 6.50 6.80 7.50

Elong. 4.05 4.40 4.06 4.32 Elong CV% 8.60 9.70 9.70 9.20

Clearer Cuts / 100 Km

Total Cuts 27 69 43 53 Neps Cuts 0 0 1 0


Long Cuts 3 5 6 6

Thin Cuts 1 2 5 6

Foreign matters Cuts 10 18 11 11




Fig. 3.4 : Graphical Representation of Noil %, Yarn IPI, U % & Clearer Cuts at different Feed / Nip.

Observations : -

Yarn Unevenness % & Imperfection incr

nip, while there is no any

clearer cuts / 100 Km. Ref. Fig. 3.4

Study – 4 : - Lap batt weight plan of combing process as well as change in No. of fibres in cross section area of lap batt.

fibres in batt cross section area should be in the range of 400000 to 550000

comber preparation.

Study conducted with changing the lap weight per meter by keeping all others

parameters unchanged. Table : - 4.1 : Combing Process & Process Parameters.

Lap Parameters Changeable Parameter No. of Doubling at Unilap Total Unilap Draft Comber Parameters Feed Feed / Nip Top Comb Penetration. Waste Index Combing Speed (NPM)

4.3

19.8 19.3

40.0

27

8.85

Noil % Yarn IPI



.4 : Graphical Representation of Noil %, Yarn IPI, U % & Clearer Cuts at different Feed / Nip.

Yarn Unevenness % & Imperfection increases with increase in

, while there is no any trend observed in yarn RKM, Hairiness Index or

Ref. Fig. 3.4

weight : The alteration in comber lap batt weight require

plan of combing process as well as change in No. of fibres in cross section area of lap batt.

fibres in batt cross section area should be in the range of 400000 to 550000 for modern high production

ed with changing the lap weight per meter by keeping all others

1 : Combing Process & Process Parameters.

Lap weight Gms/ Mtrs. 20 Changeable according to Lap weight. Forward Feed 5.2 + 1.0 mm 8.0 500

4.7 5.2 5.9

19.3 19.5 18.6

48.4

56.9

73.469

43

8.73 8.89

Yarn IPI Cuts/100 Km Yarn U %


Page 20

.4 : Graphical Representation of Noil %, Yarn IPI, U % & Clearer Cuts at different Feed / Nip.

eases with increase in feed amount per

trend observed in yarn RKM, Hairiness Index or

The alteration in comber lap batt weight requires change in draft

plan of combing process as well as change in No. of fibres in cross section area of lap batt. The number of

for modern high production

ed with changing the lap weight per meter by keeping all others

53

9.00

Yarn U %



Table – 4.2 : Detail Fibre Analysis of Lap, Combed Sliver & Comber Noil Waste at different Lap Weight.

Lap Weight / Gms. 70 72 74 76

No. of Fibres in Area of cross section in Lap

463485 476698 489937 503178

Noil% 20.1 20.0 19.9 20.0

Unilap

Total Neps 196

Total Neps Size 650

Fibre Neps 182

Fibre Neps size 622

SCN 13

SCN size 1019


Neps Size 751 - 1050 um 12.8



SFC(W)% 9.9

SFC(n)% 28.3

5%L(n) 36.4



13.0 to 20.0 mm. 24.5

21.0 to 30.0 mm 30.7

Above 31.0 mm 14.7

Micronaire 3.84

MR 0.86

IFC% 8.5

Comber Sliver


Neps Removal Efficiency % 75.5 68.4 71.4 71.4


Fibre Neps 47.0 61.0 55 55

Fibre Neps size 611.0 610.0 622 620

SCN 1.0 1.0 1.0 1.0

SCN size 985 1018 867 1019


Neps Size 751 - 1050 um 8.8 9.5 11.9 10.9





SFC(W)% 4.6 5.5 5.3 5.5

SFC(n)% 12.5 14.6 14.0 14.5

5%L(n) 37.9 37.7 37.6 37.5


Less than 12.0 mm. 12.4 14.6 14.1 14.5

13.0 to 20.0 mm. 28.8 30.6 30.0 30.6

21.0 to 30.0 mm 37.9 36.1 36.9 36.6

Above 31.0 mm 18.5 13.8 16.8 15.9

Micronaire 3.99 3.94 3.96 4.01

MR 0.91 0.9 0.9 0.91

IFC% 5.8 6.2 6.2 5.7

Noil Waste

Total Neps 766 938 905 926


Fibre Neps 716 880 858 873


SCN 50 58 47 53

SCN size 1029 1042 1059 1026


Neps Size 751 - 1050 um 13.7 14.4 13.9 14.5



SFC(W)% 55.7 57.4 58.2 58

SFC(n)% 77.5 78.8 79.5 79.5

5%L(n) 19.9 19.5 19.2 19.3


Less than 12.0 mm. 77.5 78.8 79.6 79.6

13.0 to 20.0 mm. 17.6 16.7 16.1 16.1

Above 21.0 mm 4.9 4.4 4.3 4.2

Micronaire 3.35 3.43 3.43 3.43

MR 0.67 0.66 0.66 0.65

IFC% 19.9 21.3 21.7 22.6



Fig. 4.1 : Graphical Representation of Combed Sliver Neps / Gms, NRE %, UQL (mm) & SFC % with different

lap weight & No. of fibres in Lap cross section area.

Observations : - Combing fibre properties obtained best at 70 Gms / Mtrs, while there

is no any significant difference observed in any parameters with 72, 74 & 76

Gms/Mtrs. Table 4.3 : Yarn results with different Lap batt weight Gms / Mtrs. Lap batt Weight / Gms. 70 72 74 76

Noil% 20.1 20.0 19.9 20.0


U% 8.43 8.42 8.67 8.63

Thin (-50%) 0.0 0.0 0.1 0.0

Thick (+50%) 5.9 6.4 7.8 8.8

Neps (+200%) 26.6 23.9 30.6 31.0

Total 32.5 30.3 38.5 39.8

Hairiness 5.11 4.98 5.07 5.50

Sh 0.99 0.95 0.99 1.06

FD /KM 1.60 1.75 1.70 0.95

Veg/Km 0.85 1.10 0.90 0.35

RKM 18.7 18.3 18.1 18.7

RKM CV% 5.70 4.70 6.30 6.70

Elong. 4.37 4.53 4.37 4.16

Elong CV% 7.80 5.70 9.40 8.40

48

62

56 56

75.5

68.471.4 71.4

32.0 31.6 31.731.5

12.514.6 14.0 14.5

0

10

20

30

40

50

60

70

80

463485 476698 489937 503178

70 72 74 76

Neps / Gms

NRE %

UQL (mm)

SFC %

No. of Fibres in Cross Section

Lap Gms/ Mtrs.



Classimat - Cop (/100 KM) Objectionable Faults - Short Class

(A4+B4+B3+C4+C3+C2+D4+D3+D2+D1) 6.0 17.0 22.0 12.0 Long faults - ( E+F+G) 5.0 13.0 12.0 22.0 Long thin faults ( I1+I2) 0.0 0.0 0.0 0.0 Thin faults ( H1+H2) 0.0 0.0 0.0 0.0 Remaining short faults (A3+B2+C1) 14.0 10.0 18.0 8.0 Raw material faults (A1+A2+B1) 72.0 38.0 82.0 57.0

Total faults 97.0 78.0 133.9 99.9

Clearer Cuts/100Km


Neps Cuts 1 0 0 0


Long Cuts 13 16 9 11

Thin Cuts 1 0 3 3

Foreign fibre Cuts 7 10 13 11


Fig. 4.2 : Graphical Representation of Yarn Results with different lap weight.

Observations : -

1. Yarn imperfection observed nearly same at 70 & 72 Gms / Mtrs and 74 & 76

Gms / Mtrs. However there is significant increase in yarn imperfection with 74

& 76 Gms as compared to 70 & 72 Gms/Mtrs.

2. Hairiness index observed considerably high at 76 Gms /Mtrs.

32.5 30.3 38.5 39.8

18.7 18.3 18.1 18.7

97.078.0

133.9

99.9

6878

65 56

0.0

20.0

40.0

60.0

80.0

100.0

120.0

140.0

160.0

70 72 74 76

Yarn Imperfection

Yarn RKM

Total Classimat Faults

Clearer Cuts / 100 Km.

Lap Weight Gms / Mtrs.



3. There is no any trend observed for Yarn RKM, Classimat faults & clearer cuts

or any other Quality parameters.

Study – 5 : - Combing Speed : The combing speed determined by the Nipping rate per minutes

corresponds to the number of revolution of the circular comb carrier per minutes. The higher the nipping

rate per minute, the higher the production speed of the comber.

Study conducted with changing the combing speeds i.e. NPM / Minutes by keeping all

others parameters unchanged. Table : - 5.1 : Combing Process & Process Parameters.

Lap Parameters Gms / Mtrs. 74.0 No. of Doubling at Unilap 20 Total Unilap Draft 1.59 Comber Parameters Feed Forward Feed Feed / Nip 5.2 Top Comb Penetration. + 1.0 mm Waste Index 8.0 Changeable Parameter Combing Speed Nips / Minutes i.e. 400/440/480/500

Table – 5.2 : Detail Fibre Analysis of Lap, Combed Sliver & Comber Noil Waste at different Combing Speed.

Combing Speed (Feed/Nip) 400 440 480 500

Noil% 18.8 18.9 18.8 18.8

Unilap

Total Neps 150

Total Neps Size 652

Fibre Neps 141

Fibre Neps size 630

SCN 8.5

SCN size 1006


Neps Size 751 - 1050 um 11.8



SFC(W)% 7.4

SFC(n)% 22.6

5% SL (n) 37.0





13.0 to 20.0 mm. 22.6

21.0 to 30.0 mm 34.5

Above 31.0 mm 18.8

Micronaire 3.91

MR 0.89

IFC% 7.5

Comber Sliver



Fibre Neps 45 53 40 52


SCN 1 1 1 1

SCN size 1033 881 875 883


Neps Size 751 - 1050 um 7.0 10.4 11.7 10.1



SFC(W)% 4.1 4.3 4.4 4.6

SFC(n)% 11.3 11.7 12.3 12.7

5%L(n) 37.9 38.0 37.8 38.1


Less than 12.0 mm. 11.4 11.7 12.3 12.7

13.0 to 20.0 mm. 27.6 27.1 27.2 27.3

21.0 to 30.0 mm 38.6 38.8 38.3 37.9

Above 31.0 mm 19.9 20.3 20.1 19.8

Micronaire 4.11 4.09 4.09 4.00

MR 0.93 0.92 0.93 0.92

IFC% 5.4 5.4 5.3 5.7

Noil Waste

Total Neps 640 626 586 594


Fibre Neps 602 589 544 556


SCN 38 37 42 39

SCN size 1025 1067 1000 995


Neps Size 751 - 1050 um 14.1 14.1 15.7 15.6





SFC(W)% 55.6 57.2 56.7 55.1

SFC(n)% 77.6 78.8 78.3 77.3

5%L(n) 20.2 19.7 20.0 20.3


Less than 12.0 mm. 77.6 78.8 78.2 77.2

13.0 to 20.0 mm. 17.3 16.6 16.6 17.4

Above 21.0 mm 5.0 4.5 5.1 5.3

Micronaire 3.45 3.45 3.45 3.48

MR 0.68 0.68 0.69 0.68

IFC% 19.6 20.0 19.3 19.8

Fig. 5.1 : Graphical Representation of Noil %, Combed Sliver Neps/Gm., SFC % & UQL (mm) at different

combing speed.

Observations : -

There is no any trend observed at different combing speed for Noil %,

Neps/Gms, UQL (mm). However SFC % increases with increase in combing

speed. Ref. Fig. 5.1

Similarly there is no any trend observed for neps size & length distribution at

different combing speed.

18.8 18.9 18.8 18.8

46

54

41

53

11.3 11.7 12.3 12.7

32.3 32.4 32.3 32.5

400 440 480 500

Noil % Neps / Gms SFC (n) % UQL (mm)



Table 5.3 : Yarn Results at different combing speeds. Combing Speed (Nips/Minutes) 400 440 480 500

Noil% 18.8 18.9 18.8 18.8

Fin. Draw Frame U % 1.79 1.73 1.62 1.72

Ring Yarn Results

U% 8.65 8.72 8.80 8.91

Thin (-50%) 0.1 0.0 0.1 0.0

Thick (+50%) 6.3 8.4 10.4 11.6

Neps (+200%) 26.0 31.5 41.0 49.7

Total 32.4 39.9 51.5 61.3

Hairiness 5.02 4.98 5.03 5.01

Sh 0.96 0.96 0.98 0.98

FD /KM 1.10 1.40 1.05 1.45

Veg/Km 0.50 0.85 0.65 1.00

RKM 17.70 18.51 18.22 17.19

RKM CV% 7.40 5.40 6.30 6.20

Elong. 3.69 4.07 4.21 4.14

Elong CV% 9.30 11.00 9.00 10.70

Classimat - Cop (/100 KM)

Objectionable Faults - Short Class (A4+B4+B3+C4+C3+C2+D4+D3+D2+D1) 13.0 11.0 15.0 33.8

Long faults - ( E+F+G) 5.0 29.0 17.0 27.5 Long thin faults ( I1+I2) 0.0 0.0 0.0 0.0 Thin faults ( H1+H2) 0.0 0.0 0.0 0.0 Remaining short faults (A3+B2+C1) 4.0 7.0 16.0 27.5 Raw material faults (A1+A2+B1) 35.0 53.0 55.0 120.5

Total faults all classes 57.0 99.9 103.0 209.3

Clearer Cuts / 100Km


Neps Cuts 0 0 1 0


Long Cuts 3 5 6 6

Thin Cuts 1 2 5 6

Foreign Fibre Cuts 10 18 11 11




Fig. 5.2 : Graphical Representation of Different Classimat faults with different combing speed.

Fig. 5.3 : Graphical Representation of Different Yarn IPI, U % & RKM at different combing speed.

Observations : -

1. Classimat faults significantly increases with increase in combing speed.

Similarly yarn imperfection increases with increase in combing speed. Ref. Fig.

5.2 & 5.3

57.0

99.9 103.0

209.3

35.0

53.0 55.0

120.5

5.0

29.017.0

27.5

0.0

50.0

100.0

150.0

200.0

250.0

400 440 480 500

Total CMT Faults

Raw Material Faults

Remaning Short faults

Long Faults

32.4

39.9

51.5

61.3

8.7 8.7 8.8 8.9

17.7 18.5 18.2 17.2

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

400 440 480 500

Yarn IPI Yarn U % RKM



2. There is no significant difference or any trend observed for any others quality

parameters by changing the combing speed.

Study – 6 : - Type of Feed : The kind of feed shows whether feed occurred while the combing

nipper was swinging forward or backward.

Usually backward feed being used for high degree of combing operation mostly

suitable for very fine count’s range i.e. above 60sNE where high mean length

improvement requires to spun the fine count yarn. However we have conducted this

study just for quality comparison. In this study too we observe 22.5 % comber Noil at

minimum workable waste index by keeping all others parameters same as previous

studies, therefore to conduct the study at same noil % (i.e. 22.5 %) we had increased

comber waste index in forward feed too. Table : - 6.1 : Combing Process & Process Parameters.

Lap Parameters Gms / Mtrs. 74.0 No. of Doubling at Unilap 20 Total Unilap Draft 1.59 Comber Parameters Combing Speed 500 NPM Feed / Nip 5.2 Top Comb Penetration. + 1.0 mm Waste Index Adjusted according to comber Noil % Changeable Parameter Type of Feed Forward & Backward Feed

Table : - 6.2 : Detail Fibre Analysis of Lap, Combed Sliver & Comber Noil Waste at different Feed.

Type of Feed Forward Feed Backward Feed

Noil% 22.4 22.5

Unilap

Total Neps 146

Total Neps Size 653

Fibre Neps 136

Fibre Neps size 627

SCN 10

SCN size 1011

Neps Size Distribution Neps Size 450 - 750 um 85

Neps Size 751 - 1050 um 12.2





SFC(W)% 9.6

SFC(n)% 27.9

5%L(n) 36.6



13.0 to 20.0 mm. 24.9

21.0 to 30.0 mm 30.6

Above 31.0 mm 15.0

Micronaire 3.76

MR 0.84

IFC% 9.1

Comber Sliver

Total Neps 51 41

Neps Removal Efficiency % 65.1 71.9

Total Neps Size 611 606

Fibre Neps 50 41

Fibre Neps size 608 599

SCN 1 1

SCN size 813 963

Neps Size Distribution Neps Size 450 - 750 um 91.5 91.3

Neps Size 751 - 1050 um 8.3 6.8

Neps Size above 1051 um 0.3 0.9

Length Analysis UQL(W) 31.6 31.9

SFC(W)% 4.8 4.0

SFC(n)% 13.0 11.1

5%L(n) 37.6 37.8


Less than 12.0 mm. 13.0 11.1

13.0 to 20.0 mm. 29.5 29.0

21.0 to 30.0 mm 38.3 39.2

Above 31.0 mm 16.8 18.2

Micronaire 3.99 3.96

MR 0.90 0.91

IFC% 5.8 5.7

Noil Waste

Total Neps 618 624



Total Neps Size 665 673

Fibre Neps 578 574

Fibre Neps size 639 644

SCN 40 50

SCN size 1031 994

Neps Size Distribution Neps Size 450 - 750 um 82.8 81.8

Neps Size 751 - 1050 um 12.9 13.5

Neps Size above 1051 um 3.6 4.2

Length Analysis UQL(W) 16.2 16.0

SFC(W)% 54.6 55

SFC(n)% 76.7 76.9

5%L(n) 19.9 19.9


Less than 12.0 mm. 76.8 76.8

13.0 to 20.0 mm. 18.3 18.2

Above 21.0 mm 0.8 0.9

Micronaire 136 132

MR 0.67 0.67

IFC% 20.9 20.5

Fig. 6.1 : Graphical Representation of Noil %, Combed Sliver Neps/Gm., SFC % & UQL (mm) at different

feed.

65.1

71.9

51

41

13.0 11.1

Farward Feed Backward Feed

Neps Removal Efficiency % Neps / Gms SFC (n) %




Observations : - Short fibre removal & Neps removal observed better with backward

feed as compared with forward feed.

with backward feed. Ref. Fig. 6.1 & 6.2.

Table 6.3 : Yarn Results at different Type of Feed

Noil%

Finisher Draw Frame U %

U%

Thin (-50%)

Thick (+50%)

Neps (+200%)

Total

Hairiness

Sh

FD /KM

Veg/Km

RKM

RKM CV%

Elong.

Elong CV%

Classimat - Cop (/100 KM)

Neps Size 450 - 750 um

91.5 91.3

Forward Feed



: Graphical Representation of Neps size distribution of Combed Sliver at different feed.

Short fibre removal & Neps removal observed better with backward

feed as compared with forward feed. Neps size above 750 um is also

Ref. Fig. 6.1 & 6.2.

Table 6.3 : Yarn Results at different kind of feed. Forward Feed Backward Feed

22.4 22.5

1.89 2.29

8.44 8.55

0.0 0.0

7.7 6.1

29.2 16.9

36.9 23.0

4.95 5.03

0.96 1.00

1.95 0.90

0.65 0.25

19.32 19.26

6.30 6.90

4.82 4.52

7.50 6.20

Neps Size 751 - 1050 um Neps Size above 1051 um

8.30.3

6.80.9

Forward Feed Backward Feed


Page 33

Combed Sliver at different feed.

Short fibre removal & Neps removal observed better with backward

above 750 um is also removed better

Backward Feed

22.5

2.29

8.55

0.0

6.1

16.9

23.0

5.03

1.00

0.90

0.25

19.26

6.90

4.52

6.20

Neps Size above 1051 um

0.9



Objectionable Faults - Short Class

(A4+B4+B3+C4+C3+C2+D4+D3+D2+D1) 12.0 18.0 Long faults - ( E+F+G) 4.0 7.0 Long thin faults ( I1+I2) 0.0 0.0 Thin faults ( H1+H2) 0.0 0.0 Remaining short faults (A3+B2+C1) 15.0 4.0 Raw material faults (A1+A2+B1) 50.0 38.0

Total faults all classes 81.0 67.0

Clearer Cuts/100Km

Total Cuts 56 91

Neps Cuts 2 0

Short Cuts 30 38

Long Cuts 12 32

Thin Cuts 0 1

Foreign Fibres Cuts 11 9

Off Count Cuts 1 4

Fig. 6.3 : Graphical Representation of Different Yarn IPI, CMT Faults, Clearer cuts & RKM at different

kind of feed.

36.9

23.0

81.0

67.0

56

91

19.3 19.3

Farward Feed Backward Feed

Yarn Imperfection Total CMT Faults / 100 Km. Total Clearer Cuts / 100 Km. Yarn RKM



Fig. 6.4 : Graphical Representation of Different CMT classes at different kind of feed.

Observations : -

1. Comber sliver U % observed high at backward feed and same trend remains in

Fin. DF sliver & yarn U %.

2. Yarn imperfection & Total classimat faults significantly reduced with backward

feed as compared to forward feed, however yarn RKM remains unchanged. Ref.

Fig. 6.3 3. Yarn clearer cuts observed high with backward feed, mainly due to long & off

count cuts. Same trend was also observed in classimat test results, there also

long & short thick places defects (i.e. process added defects) observed high with

backward feed while neps class defects removed significantly. Ref. Fig. 6.4

Conclusion : -The overall outcome of these studies are as follows : -

1. Top Comb Penetration depth at constant Waste index : - Comber Noil % increases

with increase in top comb penetration depth, subsequently neps removal efficiency

also increases. Fibre length & SFC % of combed sliver not much affected with

change in top comb penetration depth.

2. Top Comb Penetration depth at same Noil % by adjusting Waste index : - Even at

same noil %, Neps removal efficiency increases significantly with increase in top

comb penetration depth subsequently yarn imperfection & Foreign matters

12.04.0

15.0

50.0

81.0

18.0

7.0 4.0

38.0

67.0

Short (Obj. Fault) Long faults Remaining short faults

Raw material faults Total faults

Forward Feed Backward Feed



significantly reduced, however fibre length, SFC % & other fibre properties are not

much affected. Classimat faults & clearer cuts doesn’t show any relation with TC

penetration, however yarn hairiness increases with increase in TC penetration

depth.

3. Feed amount per cycle : - Fibre characteristics, Neps removal efficiency etc. & noil

extraction % is not much affected with small change in feed per cycle. It has been

observed that better combing took place at lower feed amount (i.e. 4.3 & 4.7) as

compared to higher feed amount (i.e. 5.2 & 5.9). Yarn imperfections having

increasing trend with increase in feed amount while others quality parameter

doesn’t show any trend.

4. Lap batt weight : - Fibre characteristics doesn’t much affected with change in lap

batt weight, however better combing operation took place at lower batt weight.

Yarn quality not much affected with minor change in lap batt weight. Yarn

imperfection & Hairiness Index increased with higher lap batt weight. While others

quality parameters not much affected.

5. Combing Speed : - Again fibre characteristics & comber noil % not much affected

by change in combing speed, however yarn imperfection and classimat faults

increases with increase in combing speed, means uniform combing perform at

lower rate of combing speed.

6. Kind of Feed : - Higher noil extracted at backward feed with superb combing

performance compare to forward feed. Yarn Quality improves significantly with

backward feed combing.

In totality it can be concluded that yarn imperfection reduced when we reduce comber

production with respect to lap batt weight, feed amount per cycle and by combing

speed. Higher top comb penetration depth by maintaining same noil % produces the

better quality without affecting production rate. Backward feed also provide better

yarn quality without affecting production rate but high amount of noil extracted at this

kind of feed, hence this can be only utilized for fine count qualities. For better



classimat results along with lower yarn imperfection lower combing speed &

backward feed may be tried.

Recommendation : It is very clear from above studies that according to yarn count

pattern following combination may apply for best results : -

For Coarse Count Range : - Forward feed, high amount of feed with optimum

lap batt weight and with require combing speed & Noil % as per Quality &

Productivity requirement.

For Medium Count Range : - Forward feed, medium amount of feed with

optimum lap batt weight, medium combing speed & with adequate Noil % set

with maximum top comb penetration depths require as per Quality &

Productivity requirement.

For Fine Count Range : - Backward feed, low amount of feed with lower batt

weight & lower combing speed, maximum top comb penetration depth with

adequate Noil % require as per Quality requirement.

Disclaimer : - These studies conducted at state of art modern high speed spinning plant by utilizing maximum

production capacity with medium long staple cotton fibres. Different results may obtain with different spinning set

up, production rate and much depends upon cotton fibres quality. Hence users are advised to refer these studies as

a guideline and should reconfirm with their own process set up’s.

Produced By : -

Mr. Sunil Kumar Sharma – Dy. General Manager

&

Mr. Mahesh Upadhyay – Dy. Manager QAD,

Loknayak Jayprakash Narayan Shetkari Sahakari Soot Girni Ltd.

Shahada, Dist. : - Nandurbar (MS)

: Mr. Sunil Kumar Sharma, Manager – QAD,

Mobile No. : – 09552596742, 09921417107

E_mail : - [email protected]

Technology

Combing Behaviors at Different Parameters