Indian Journal of Textile ResearchVol. 4, December 1979, pp. 140-144

Improvements in Yarn Quality and Ringframe Performance in Fine Counts byHigher Licker-in and Cylinder Speeds in Carding

R S SHAHNew China Mills, Bombay

andN BALASUBRAMANIAN

Bombay Textile Research Association, Bombay 400086

Received 17 November 1978; accepted 19 October 1979

An attempt has been made to assess the improvement in carding quality in semi-high production cards resulting fromincrease in licker-in up to 800 rpm and cylinder speeds up to 300 rpm, the study beingrestricted Ito fine counts. The material wasexamined up to ring spinning to assess the effecton end breakage rate also. Increase in licker-in speed was found to improve thecleaning efficiency significantly in all the four mixings studied. There was no evidence of fibre rupture, nor any increase in nepgeneration at the higher speed. On the other hand, there was clear evidence to show that increase in licker-in speed helped toremove the immature fibre clusters and fuzzy fibres more elTectively.Although the physical properties of the yarn were nearlyunalTected, a significant reduction in ringframe end breakage rate could be obtained at higher licker-in speed. Increase incylinder speed was associated with reduced cylinder load, but without change in transfer efficiency. There was a consistentimprovement in card cleaning efficiency with increase in speed for all the mixings. Although yarn strength and evenness werenot much alTected,the yarn imperfections showed consistent reduction at higher cylinder speed with three out offour mixings.Ringframe end breaks also showed a significant reduction at the higher cylinder speed with all the mixings, except 70s.

Majority of the cards in the industry at present are ofsemi-high production type and it would be useful toexamine if the quality of carding, if not the productionrate, on these machines could be improved byincreasing the speeds of licker-in and cylinder to thelevels found on high production cards. In most cases,this is possible without much investment, provided themachines are in sound mechanical condition. Even inmills equipped with high production card, speeds oflicker-in and cylinder are in many instances kept low,especially while processing fine mixings, mainlybecause of the absence of precise information about thebenefits that accrue from higher speeds. A detailedinvestigation was, therefore, carried out to assess theimprovements resulting from higher licker-in andcylinder speeds in fine mixings. The results obtainedare presented in this paper.

Earlier work 1- 5 on licker-in speed had shown thathigher speeds are generally beneficial in givingimproved cleaning and better quality, providedtransfer from licker-in to cylinder is not affected.Higher cylinder speed was also found beneficial inreducing cylinder load and improving carding qualityin metallic card" - II. But the effect of employing higherspeeds for licker-in and cylinder on ring frameperformance has not been investigated in detail so far.In the present study, this aspect has been covered ingreater detail. The type of fibres which get removed inthe licker-in region at higher licker-in speed was also

140

examined critically. The effect of cylinder speed oncylinder load and transfer efficiency was alsoinvestigated.

Experimental ProcedureAll the studies were carried out on Platts semi-high

production card at a doffer speed of 9-11 rpm. Thelicker-in speed was varied from 490 to 810 rpm,keeping other speeds constant. Exhaustive studies weremade on four fine mixings to get a critical insight intothe maturity and Micronaire value of fibres which getremoved at higher licker-in speeds and to assess theeffect of licker-in speed on card waste, cleaningefficiency and nep level and fibre length characteristicsin card sliver. The studies were then extended ontwo mixings to examine the effect on ringframe endbreakages and yarn quality. The effect of cylinder speedwas assessed by raising the speed from 190 to 300 rpm,keeping other parameters constant. The study wasmade on three fine mixings and on a polyester materialused in blend spinning.

For each trial, 20 blow room laps were collected; 10laps were carded at the lower speed and the other 10 atthe higher speed. Card waste was assessed by runningthree full laps under each experimental condition onthe chosen card. Card cleaning efficiency, nep level andthe fibre length parameters in the card sliver were alsoexamined. The card sliver was then processedseparately up to ring spinning under identical

SHAH & BALASUBRAMANIAN: IMPROVEMENT IN YARN QUALITY & RINGFRAME PERFORMANCE IN FINE COUNTS

processing conditions to examine the effect on yarnquality and ringframe performance. As fine mixingswere covered, the spinnings incorporated combing.For assessing ringframe performance, simultaneousend breakage study was carried out by creeling one sidewith material carded at the slower speed and the otherside with material made at the higher speed. The effectof side (of ringframe) was eliminated by interchangingthe creel material halfway through the study.

Licker-in SpeedMicronaire values of licker-in lint-T.o find out the

type of fibres which get removed by the licker-in atdifferent speeds, Micronaire tests were done on the lintretrieved from the droppings by passing the samethrough the Shirley analyser. The study was carried outon four mixings.

The data presented in Table 1 show that theMicronaire value of the licker-in lint drops withincrease in licker-in speed, with all the mixings studied,indicating preferential removal of clusters of immaturefibres at the higher Ticker-in speed. Causticaire test 12

on the lint confirmed the lower maturity ofthe fibres inthe droppings at the higher speed. The differentialdyeing test13 was also used to get further confirmation

of the differences in maturity. This consists in dyeingthe material in a bath containing diphenyl red SLNand chlorantine fast green BLL. The mature fibres arestained red and the immature fibres green by thisdyeing. The differential dyeing test results also confirmthat the lint in the droppings is of relatively lowermaturity at higher licker-in speed.

These results clearly indicate preferential removal ofimmature fibre clusters from the lap at the higherlicker-in speed. Another explanation for this finding isthat the immature fuzzy-like short fibres in the cottonmay be getting removed more effectively at the higherlicker-in speed.

Since the higher licker-in speed was found moreeffective in removing immature fibres, a detailed studywas carried out to assess the overall benefits in cardingobtained from the same.

Card waste and cleaning efficiency-Detailed studieson card waste and cleaning efficiency at the two licker-in speeds were made on four fine mixings. Further, thenep level and fibre length parameters were tested in thecard sliver to find out if there is fibre damage at thehigher licker-in speed. The results of these studies aregiven in Tables 2 and 3.

The data presented in Table 2 show that the quantity

Table I-Micronaire Value and Maturity of Licker-in Lint at Different Licker-in Speeds

Mixing 50s 70s a 70Sb l00s

Licker-in speed, rpm 490 810 490 810 490 810 490 810Micronaire value 4.2 3.9 4.0 3.5 3.5 2.9 3.6 3.1Causticaire maturity, % 76.9 72.0 76.7 72.1 72.1 67.2 72.9 66.7DitTerential dyeing shade Reddish Greenish Reddish Greenish Reddish Greenish

Table 2-Effect of Licker-in Speed on Card Waste and Cleaning Efficiency

Mixing 70s a 70sb 60s 50s

Licker-in speed, rpm 490 810 490 810 490 810 490 810Card Waste

Licker-in waste 1.20 1.41 0.96 1.15 1.46 1.61 1.77 2.14Flat strip 2.79 2.75 2.17 1.93 3.30 3.11 2.98 2.91Cylinder/doffer fly 0.04 0.03 0.06 0.07 0.09 0.10 0.08 0.06Scavenger 0.03 0.05 0.03 0.05 0.03 0.04 0.05 0.09Total waste, % 4.06 4.24 3.22 3.20 4.88 4.86 4.88 5.20

Card- cleaning efficiency, % 87.2 90.5 82.8 87.1 87.5 92.3 85.3 94.1

Mixing

Table 3-Nep Content and Fibre Length Parameters in Card Sliver at Different Licker-in Speeds70s a 70s b 60s 50s

Licker-in speed, rpm 490 810 490 810 490 810 490 810

Nep content in card sliver, neps/g 212 171 101 92 132 143 130 132Fibre length by Baer sorter

Mean, mm 27.6 27.5 26.2 26.8 26.1 25.9Effective, mm 40.9 40.0 39.5 39.5 36.0 36.0Short fibres, % 14.9 13.3 37.9 34.4 11.5 12.0

141

INDIAN J. TEXT. RES., VOL. 4, DECEMBER 1979

of licker-in waste increases with increase in licker-inspeed, which is to be expected because of the intensivetreatment arising from the passage of a larger numberof wire points per unit length of material fed, highercentrifugal force generated at the higher speed, and thehigher forces of penetration.

Flat waste, however, tends to come down withincrease in licker-in speed, particularly in the case of70s b and 60s mixing, which may be because ofreduction in the proportion of trash in the materialtransferred to the cylinder, and the reduced size of thefibre tufts presented to the cylinder. The total cardwaste remains almost the same at the two licker-inspeeds in these two mixings, while in 70s a and 50smixings, a marginal increase in card waste results at thehigher licker-in speed.

It is further seen from Table 2 that there is asignificant improvement in card cleaning efficiency atthe higher licker-in speed in all the mixings. Theimprovement arises partly from the higher licker-inwaste and partly from the better opening of the tufts.Trash content in licker-in dropping (not given) is,however, found to be nearly the same at the two speeds.

Table 4-EfTect of Licker-in Speed on RingframePerformance and Yarn Quality

70s1()()S

MixingCount, Ne

Licker-in speed, rpm 490 810 490 810Ringframe performance

End beaks per 100 spindle hr 11.61 8.04 5.86 4.38Spindle hr observed 2460 2460 4180 4180

Physical properties of yarnActual count, Ne 95.S 97.4 62.9 62.3Corrected lea, CSP 2293 2294 2026 2016Single thread strength, g 100 99 146 ISOElongation. '?~ 5.6 5.7 5.3 5.4Uster, U'Y,. 14.3 14.2 14.9 14.8

Imperfections per kmThin-50% 112 128 239 187Thick+3 366 398 603 498Neps+3 398 408 586 521Total imperfections 876 934 1428 1206

The nep content in the card sliver is also comparableat the two licker-in speeds in all the mixings (Table 3).Fibre lengths are also comparable. These resultsclearly discount fibre damage at the higher speed.

Ringframe performance and yarn quality- Thestudies were extended in 70s b and 60s mixings to assessthe benefits of higher licker-in speed on ringframeperformance and yarn quality. Since both werecombed mixings, the material was channelised throughthe comber, keeping all other conditions identical.Comber noil tests made on the materials processed atthe two licker-in speeds showed no significantdifference, which again discounts fibre rupture at thehigher licker-in speed.

The performance at ringframe was assessed bystudying the end breakage rate by creeling the twomaterials on two sides of a frame with due interchangeof creel material.

The data presented in Table 4 show that there is asignificant reduction in ringframe end breakage rate atthe higher licker-in speed in both the mixings. Theimproved ringframe performance at the higher licker-in speed should be attributed to the higher cleaningefficiency, more intensive opening of fibre tufts andmore effective removal of immature fuzzy fibres. Yarntest results at the two speeds do not show anysignificant differences (Table 4). This confirms that thehigher licker-in speed has, at least, no harmful effect onthe fibres.

The data presented in Table 5 show that with all themixings, including polyester, card waste increasesslightly with increase in cylinder speed, primarilybecause of higher flat strip waste. The highercentrifugal force generated at the higher cylinder speedseems to be responsible for increased flat loading andflat waste. Cylinder fly also increases with increase incylinder speed. A significant improvement in cardcleaning efficiency (3-5%) is observed at the highercylinder speed with all the cotton mixings. Theimprovement is partly due to the higher flat strip wasteand partly due to the relatively more effective cardingaction between flats and cylinder.

Mixing

Table 5-Card Waste and Card Cleaning Efficiency at Two Cylinder Speeds

70s 100s Giza 100s Sudan Polyester

Cylinder speed, rpm 190 300 190 300 190 300Card waste, %

Flat strip 2.55 3.18 3.13 3.52 2.28 2.86Licker-in droppings 1.91 2.00 1.33 1.23 1.02 1.03Cylinder doffer fly 0.05 0.07 0.05 0.15 0.06 0.Q9Scavenger rod 0.03 0.03 0.Q2 0.03 0.02 0.Q2Others 0.14 0.16 0.10 0.15 0.08 0.10Total waste 4.68 5.44 4.63 5.08 3.46 4.10

Card cleaning efficiency, % 84.5 88.4 88.5 90.0 92.4 95.5

142

190 300

0.55 0.760.11 0.16

0.66 0.92

SHAH & BALASUBRAMANIAN: IMPROVEMENT IN YARN QUALITY & RING FRAME PERFORMANCE IN FINE COUNTS

Cylinder load and transfer efficiency-The cylinderload and the transfer efficiency were estimated byKryJov method". At steady state condition, the dofTerwas stopped and the drive to the flat and feed wasdisconnected. The doffer was then restarted and thematerial issuing from the doffer beyond the cylinder-doffer junction point (indicated by a clear demarcationline) was collected and weighed (which gives the load).The weight per unit length of sliver was alsodetermined by weighing a known length of sliver priorto the start of the study and from the cylinder load andhank of sliver, the transfer efficiency was estimated. T!1etest was repeated live times and the results averaged toget an estimate of the cylinder load and transferefficiency for each experimental condition. The resultsare given in Table 6.

The cylinder load is found to fall, as expected, withincrease in cylinder speed with all the mixings, but thetransfer efficiency is not improved at the highercylinder speed and remains more or less the same. Thisis because the reduction in cylinder load with increasein cylinder speed is nearly proportional to the speed.However, some of the earlier investigators found thatthe transfer efficiency improves with increase incylinder speed. Therefore, further work is required to

explain the different results obtained in the presentstudy. One of the areas in which further studies havebeen taken up in this connection is to find out whethercylinder speed will start exercising a more criticalinfluence on the transfer efficiency only after thecylinder load exceeds a certain level.

Ringframe performance-As in the case of licker-inspeed, ringframe performance was assessed bymeasurements of end breakage rate, the study beingconfined to three cotton mixings.

There is 20-30% reduction in the end breakage rateat ringframe with increase in cylinder speed in two outof three mixings (l00S mixing from Giza as well asSudan) (Table 7). But 70S mixing shows no significantreduction in end breaks at the higher cylinder speed.The improved ringframe performance at the highercylinder speed should be attributed to the better cardcleaning efficiency and improved carding quality. Aclue to the different results obtained with 70S mixingcan be had by referring to Table 6. The reduction incylinder load with increase of cylinder speed is found tobe more prominent in the two 100S mixings than in the70S mixing. This explains why the improvement inringframe performance at the higher cylinder speed ismore marked in the two 100' mixings.

Table 6-EfTect of Cylinder Speed on Cylinder Load and Transfer Efficiency

Mixing 70s lOOs Giza lOOs Sudan PolyesterDotTerspeed,rpm 9.0 10.5 9.0 11.0

Cylinderspeed,rpm 190 300 190 300 190 300 215 295Cylinderload, g 8.85 6.58 11.37 7.77 7.85 5.20 10.58 6.46Transferefficiency,% 3.48 2.88 3.15 2.91 4.49 4.32 3.25 3.82

Table 7-EfTect of Cylinder Speed on Ringframe Performance and Yarn Quality

Mixing 70s lOOS Giza l00s Sudan Polyester!.~ cotton blend

Cylinderspeed,rpm 190 300 190 300 190 300 215 295Nominal count 100' 100' 130' 130' 110' 110' 50sRingframeperformance

End breaks per 100spindlehr 6.22 5.96 12.31 9.91 6.92 4.52Spindlehr observed 2970 2970 4420 4420 3914 3914

Physicalpropertiesof yarnActualcount, Ne 102.5 102.6 128.7 131.2 109.4 110.0 49.6 49.9Correctedlea,CSP 2158 2065 1833 1896 2395 2338 2346 2489Singlethread strength,g 96 97 72 76 93 92 214 214Elongation,% 5.8 5.8 5.2 5.7 5.5 5.5 8.9 8.9Uster, U% 15.0 15.0 15.5 14.9 14.4 14.0 15.4 15.0

Imperfections/krnThin-50% 143 158 355 184 70 66 264 133

-v

Thick+3 458 455 512 446 65 58 416 352Neps+3 361 350 315 239 203 166 272 256Total imperfections 962 963 1183 869 338 290 952 741

143

INDIAN J. TEXT. RES., VOL. 4, DECEMBER 1979

Yarn characteristics-The physical characteristicsof the yarn are given in Table 7. While the yarn strengthand evenness are nearly unaffected, there is asignificant reduction in the Uster imperfections withthe two 1005 mixings and the polyester/cotton blendcount at the higher cylinder speed, The reduction inimperfections goes hand in hand with the improvedringframe performance noticed earlier with the 1005

mixings.An interesting feature of the present study is that

more than the yarn quality, ringframe end breakagesare more sensitive to carding conditions and higherlicker-in and cylinder speeds help to reduce endbreakages. It is further interesting to note that theeffects of carding conditions are seen even in combedcounts.

ConclusionsThe results of the present study indicate that the

licker-in speed could be advantageously increasedup to 800 rpm even in fine mixings without causingrupture of fibres or ncp generation, provided thesettings and licker-in wire points are satisfactory.Besides improving the cleaning efficiency, higher speedis found to be more effective in removing the immatureclusters and fuzzy short fibres from the cotton. Thoughthe yarn properties are not much affected, the higherlicker-in speed is advantageous in bringing down theend breaks at the ringframe.

With increase in cylinder speed. the cylinder loadfalls, but the transfer efficiency remains nearlyunaffected. Card waste increases slightly with increase

144

in the cylinder speed, while the card cleaning efficiencyimproves significantly. Although yarn strength andevenness are 110t much affected, there is a significantreduction in imperfections in the yarn at the highercylinder speed. There is also a significant reduction inringframe end breaks at the higher cylinder speed intwo out of the three mixings studied. ,

I

AcknowledgementOne of the authors (R.S.S.) is grateful to the

management of the New China Mills for the offer of afellowship which enabled the studies to be carried out.The authors' thanks are also due to the Director,BTRA, for permission to publish this work.

ReferencesI Spibey H,J rea t-«. 23 (1932) T183.2 Bentley E A, Text lnds, 116 (1952) 100.3 Martin F H & Hunter J R, re« Bull, 91 (1965) 36.4 Mutter W & Grinshaw K, TeXI Rec, 80 (1962) 76.5 Nozaki C et al., J Text Mach Soc Japan, 9 (1963) 167.6 Krylov V V, Technology T<'xI Ind, USSR, (2) (1962) 46; (3) 52..7 Spibey H. J Text lnst, 27 (1936) T88.8 Ghosh G C & Bhaduri S N, Proceedings, 7thloim Technological

Conference, 1965, 130. .9 Simpson J & Fiori L A, Text Res], 41 (1971) 69l.

10 Simpson J & Fiori L A, Text Res J, 42 (1972) 661.11 Bhaduri S N,Investigation of means to minimise fibre hooked ends

in cotton card and drawing slivers to develop processingorganizations oj optimum efficiency, and thus to promoteincreased utilisation of cotton. Final Report on Project FG-In-171, ATIRA, Ahmedabad, 1968.

12 Lord E,l Text Inst, 47 (1956) T635.13 Booth J E, Principles of textile testing (Butter-worth, London)

1974,194.

. ".