1. TE 550 NEW METHODS OF YARN PRODUCTION FRICTION SPINNING1SUBMITTED TO : PROF.DR.AL KRECC SUBMITTED BY: AYBALA ZCAN DEPARTMENT: TEXTILE TECHN. BY TEXTILE ENG.

2. ABSTRACT Friction SpinningorDref Spinningisatextiletechnologythat suitableforspinningcoarsecountsofyarnsandtechnicalcorewrappedyarns. Drefyarnsarebulky,withlowtensilestrengthmakingthem suitableforblanketsandmopyarns,theycanbespun fromasbestos,carbonfibresandmakefilterswaswater systems. YarnssuchasRayonandKevlarcanbespunusingthismethod. Thetechnologywasdevelopedaround1975byDr.Ernst Fehrer.[1] 2 3. INTRODUCTION Withtheadventofmodernspinningsystems,frictionalpropertiesoffiberassemblieshavegainedtechnicalimportance becauseoftheroleplayedbyinterfiberfriction. Amongstthespinningsystems,DREFprovidesagoodplatform forproductionofcorespunyarnsdueitsspinningprinciple. Itofferslessspinningtensiontothecoreandcorewillbe positionedexactlyatthecenteroftheyarn. Friction(DREF)spinningsystemisalsoknownasanOpen-end or Core sheath type of spinning system. 3 4. FRICTION SPINNING Features Of Friction Spinning Yarnproperties:lowtensilestrength Gooduniformity,highproductionrates Application:yarnsforknitting;terryyarns;weftyarns Advantages:lowmanufacturingcost;possibilityforautomation; nofast-movingparts Features:upnownolimitedapplicationpossibilities;delivery speedisindependentfromyarncount Lowenergyexpensesandlowlabor 4 5. FRICTION SPINNING Accordingtodevelopment,thecommonformofcharacterizingthefrictionalpropertiesofyarnsandfilamentsisthecoefficient offriction. Thecoefficientoffrictiondetermines;-thesurfaceproperties, -theyarn -thefabricstrength, 5 6. FRICTION SPINNING DevelopmentofDREFcore-spunyarnsunveilsapathfornew productsincluding,highperformancetextiles,sewingthreadsandintheapparels duetoitsexceptionalstrength,outstandingabrasion resistance,consistenceperformanceinsewingoperation, adequateelasticityforthestretchrequirements, excellentresistancetoperspiration, idealwashandwearperformanceandpermanentpress.6 7. Principle Of Friction (DREF) Spinning Systems Thefrictionspinningsystemconsistsof; opening&individualizationoffibresfromslivers, reassemblingofindividualizedfibres(collecting), twisting(impartingthestrengthbytwisting), withdrawingnewlyyarnformation, windingofyarn.(across-woundpackage)7 8. SCHEMATIC VIEW OF FRICTION SPINNING SYSTEMFollowing process line8 Fig.1-SchematicView of Friction Spinning 9. Basic Working Principle Of Friction (Dref) Spinning 1-opened fibers2-roller3-rotating drums The figure 2 describesthe DREFspinningprinciple wheretheopenedfibres (1)maderollwithanaid ofamechanicalroller(2) forreassemblingand twisting.Fig.2-Individualizing of fibers on the drums Fibers are delivered onto the drum surface (3), which transports and stacks the fibers to the fiber bundle rotating between two surfaces moving in opposite directionsinfig.1.9 10. BasicWorkingPrincipleofFriction(DREF)Spinning Fig.1-SchematicView of Friction Spinning Collected drums 412 3 Frictionspinningusestwofrictionsurfacestorollupfibresintoayarn. Thefibresflowfreelytotworotatingfrictiondrums(3)(spinning drums,frictionrollers,torquerollers). 10 Thesurfacesatthenipofthetwodrums(4)moveinoppositedirection totwistthefibrescollectedinthenip. 11. BasicWorkingPrincipleofFrictionSpinning Collected drumsFollowing process lineFig.1-SchematicView of Friction SpinningTheyarnisformed frominsideoutwards, bythesuperimposition oftwistingofindividual fibres.4Thereforetwistsby fiberarrangementare generated.Duetoseparateyarn windingandmethodof twistinsertion,ithas capabilitytogoforhigh productionrate. 11 12. Basic Working Principle of Friction Spinning The twisting rate in friction spinning is related to the drum rpm, drum diameter and yarn diameter as indicated below.Because of the very large ratio between the drum and yarn diameters, the rotational speed of the drums need not be high, provided adequate twist efficiency is achieved.The twist efficiency is reduced due to the slippage between the yarn in the nip and the drum surfaces. It is possible to have a twist efficiency as low as 40%. But even allowing for this, friction spinning is still the most efficient way of inserting twist to fibres, because twist is directly applied 12 to yarn end. 13. YARN FORMATON N FRCTON SPNNNG SYSTEM The mechanism of yarn formation is quite complex. It consists of three distinct operations, namely: Feedingof fibers, Fibers integration Twist insertion.13 14. YARN FORMATON N FRCTON SPNNNG SYSTEM 1-FEEDING The individualized fibers are transported by air currents and deposited in the spinning zone. The mode of fiber feed has a definite effect on fiber extent and fiber configuration in yarn and on its properties. There are two methods of fibre feed : a)Direct feed b)Indirect feed.14 15. YARN FORMATON N FRCTON SPNNNG SYSTEM FEEDINGIn case of direct feed, fibers are fed directly (b) or forward guidance onto the rotating fiber mass that outer part of the yarn tail. In indirect feed (c ) or bacward guidance, fibers are first accumulated on the ingoing roll and then transferred to the yarn tail. Figure 3 (b) and (c) are showing the above methods of fiber feed.15Fig.3-Direct and Indirect Fiber Feeding Methods 16. YARN FORMATON N FRCTON SPNNNG SYSTEM 2-FIBERS INTEGRATION:The fiber orientation is highly dependent on the decelerating fibers arriving at the assembly point through the turbulent flow. The fibers in the friction drum have two probable methods for integration of incoming fibres to the sheath. One method, the fiber assembles completely on to perforated drum before their transfer to the rotating sheath. In the other method, fibers are laid directly on to rotating 16 sheath. 17. YARN FORMATON N FRCTON SPNNNG SYSTEM 3-TWIST INSERTION:In friction spinning, the fibers are applied twist with more or less one at a time without cyclic differentials in tension in the twisting zone. Therefore, fiber migration may not take place in friction spun yarns. The mechanism of twist insertion for core type friction spinning and open end friction spinning are different,which are described next slayt.17 18. YARN FORMATON N FRCTON SPNNNG SYSTEM TWIST INSERTION:a-In Core Type Friction Spinning Core is made of a filament or a bundle of staple fibers is false twisted by the spinning drum. The sheath fibers are deposited on the false twisted core surface and are wrapped helically over the core with varying helix angles. It is believed that the false twist in the core gets removed once the yarn is emerged from the spinning drums, so that this yarn has virtually twist less core. 18 19. YARN FORMATON N FRCTON SPNNNG SYSTEM TWIST INSERTION:b-In Open End Type Friction Spinning The fibers in the yarn are integrated as stacked cone. The fibers in the surface of the yarn found more compact and good packing density than the axial fibres in the yarn. The Figure 4 shown the arrangement of fibers in the DREF-3 yarn as stacked cone shape .19 20. COMPARE WITH RING SPINNING AND ROTOR SPINNING.. Unlike ring spinning and rotor spinning, friction spinning imposes very little tension to the yarn. So the ends-down rate in friction spinning is very low and the yarn can be withdrawn from the nip of the drums at a very high speed, say 300 m/min. This makes friction spinning more productive than ring and rotor spinning. Similar to rotor spinning, friction spinning uses sliver feed and tooth drafting. 20 21. DEVELOPMENT CATEGORES OF FRCTON SPNNNG DREF-1 DREF-2 DREF-3 DREF-5 DREF-2000 DREF-300021 22. TECHNOLOGCAL DEVELOPMENTS OF DREF SYSTEM Dref is the trade name given to the machine based on friction spinning system, which was developed by Dr E Fehrer of Austria. This process is primarily suited to spin coarser and recycled yarns but most suitable to spin technical yarn. Today, Dref is only spinning machine, which got commercial success.The different versions of the machine are DREF-1, DREF-2, DREF-3, DREF5, DREF-2000 and DREF-3000. DREF-1 friction spinning system has single friction drum (fig.5), where as DREF-2 has two friction drums (fig.6).22 Fig.5-Dref-1Schematic Fig. (Single Drum)Fig.6-Dref-2 Schematic Fig. (Double Drum) 23. TECHNOLOGCAL DEVELOPMENTS OF DREF SYSTEM Dref-2 is one of the earliest friction spinning machines introduced in the market somewhere around 1977 primarily for long staple fibers to produce coarser yarns was exhibited in the year 1975 at ITMA exhibition.Dr Ernst Fehrer began work on the development of the DREF 3 friction spinning system, which was first presented to the public at the 1979 international textile machinery exhibition (ITMA'79) in Hanover.Dref-3 is a development over of Dref-2 system for improving the quality of yarn,productivity and count range came to the market in the year 1981,and this is a core-sheath type spinning arrangement and produce component yarns which can not be produce by other spinning machines(Fig.7-Dref 3 ).Fig.7-Dref-3 Process Schema 23 24. Technological Developments Of Dref System Dref -2 End-Uses Areas Blanketsfor the homes, hotels, hospitals, camping, military uses, plaids etc. Cleaning rags and mops from cotton waster and various waste-blends Deco- and upholstery fabrics (fig.8) Outerwear and leisure-wear Filter cartridges for liquid filtration Secondary carpet backing for tufting carpets Canvas and tarpaulins for the military and civil sectors Fif.8-upholstery fabrics High-tenacity core yarn for ropes, transport and conveyor belts Asbestos substitutes for heavy protective clothing (protective gloves, aprons etc) packing, gaskets, clutch and brake-linings, flame retardant fabrics etc. Filter yarns for the cable, shoe and carpet industries Carpet Yarns (Berber carpets, hand-woven and hand-knotted carpets) and filler weft yarns for carpets. 24 25. TECHNOLOGCAL DEVELOPMENTS OF DREF SYSTEM Dref 5 was developed by Schalafhorst, Suessen and Fehrer after Dref 3,but this spinning system was not commercialized due to to various technical difficulties. In 1999 ,Dref 2000 was demonstrated at ITMA exhibition (fig.9). It has S and Z direction is possible without mechanical alterations to the machine.And this machine also has dust extraction for secondary fibers and low energy costs due to the use of only Fig.9-Dref 2000 25 26. TECHNOLOGCAL DEVELOPMENTS OF DREF SYSTEM Dref-3 spinning system has advantages over Dref-2 which are; oThe sheath fibers are attached to the core fibers by the false twist generated by the rotating action of drums.[fig.10] oTwo drafting units are used in this system, one for the core fibers and other for the sheath fibers 26 Fig.10-Dref-3 Schematic Figure 27. TECHNOLOGCAL DEVELOPMENTS OF DREF SYSTEM Dref 2000 End-Uses Areas Blanketsfor the homes, hotels, hospitals, camping, military uses, plaids etc. Deco- and upholstery fabrics Outerwear and leisure-wear Filter cartridges for liquid filtration Secondary carpet backing for tufting carpets (fig.11) Canvas and tarpaulins for the military and civil sectors High-tenacity core yarn for ropes, transport and conveyor belts Asbestos substitutes for heavy protective clothing (protective gloves, aprons etc) packing, gaskets, clutch and brake-linings, flame retardant fabrics etc. Filter Yarns for the cable, shoe and carpet industries Carpet Yarns (Berber carpets, hand-woven and handknotted carpets) and filler weft yarns for carpets. (fig.9)Fig.11-Dref 2000 end uses,Gloves and secondary carpet backing yarns,TBA Textiles27 28. TECHNOLOGCAL DEVELOPMENTS OF DREF SYSTEM Fig.12- Dref 3000The latest innovation of spinning system is exhibited in the ITMA 2003, the first public appearance of the DREF 3000 was made. Higher bobbin weights through 200 mm winding traverse was used (fig.12). Apart from other dref types,in Dref 3000,the drafting unit can handle all types of synthetic fibres. 28 29. TECHNOLOGCAL DEVELOPMENTS OF DREF SYSTEM Dref 3000 End UsesArea Backingfabrics for printing, electrical insulation, hoses, filter fabrics Hot air filtration and wet filtration in food and sugar industries. Clutch lining and brake lining for automotive industries.(fig.13) Fire resistant protecting clothing,aircraft and contract carpeting, Conveyor and transport belts. Composites for aviaton and automotive industries.Fig.13-Brake linings for auotomotive industry produced by Dref 3000 method. 29 30. TECHNOLOGCAL DEVELOPMENTS OF DREF SYSTEM Dref 3000 spinning system has a drafting unit can handle all types of synthetic fibres such as; aramid, FR and pre-oxidized fibres, polyamides, glass fibers in blends phenol resin fibres (e.g. Kynol), melamine fibres (e.g. Basofil), melt fibres (e.g. PA, PES, PP), natural fibres (wool, cotton, jute, linen, flax, etc.), Dref 3000 has some advantages over other friction systems ; Production of both S and Z yarns at any time without mechanical alterations to the machine. Reduced yarn preparation costs due to high sliver weights (card slivers) Higher Bobbin weights through 200mm winding traverse. DREF 3000 core yarns offer high output, breakage-free spinning and weaving mill operation and thus up to 95% efficiency can be achieved. 30 31. SPINNING TENSION FOR DREF YARNS Friction spun yarns have less spinning tension during the yarn formation.(Fig.14) Due to less tension during the spinning the core component can be placed exactly at the centre of the yarn.Fig.14-Spinning Tension for DREF Ring and Rotor Yarns31 32. PROPERTIES OF FRICTION SPUN YARNS Friction spun yarns (DREF) yarns have bulky appearance (100-140% bulkier than the ring spun yarns).The twist is not uniform and found with loopy yarn surface.Usually weak as compared to other yarns.The yarns possess only 60% of the tenacity of ring-spun yarns and about 90% of rotor spun-yarns.The breaking elongation of ring, rotor and friction spun yarns is equal. 32 33. PROPERTES OF FRCTON SPUN YARNS Depending on the type of fiber, the differences in strength of these yarns differ in magnitude. 100% polyester yarns-strength deficiency is 32% 100% viscose yarns-it ranges from 0-25% In polyester-cotton blend, DREF yarns perform better than their ringspun counterparts. 70/30% blend yarn-superior in strength by 25% DREF yarns are inferior in terms of unevenness, imperfections, strength variability and hairiness. The friction spun yarns are more hairy than the ring spun yarns DREF yarns are most irregular in terms of twist and linear density while ring spun yarns are most even. 33 34. PROPERTIES OF HYBRID YARNS/DREF CORE YARNS If one yarn creates out of 2 or more single yarn components is called hybrid yarn. Hybrid yarns are used; For reinforced plastic (fig.15) Yarn Properties Core/Sheath structure with centric position of the reinforcing filament Zero twisted reinforced filament gives best strength result Definable fiber matrix proportion Protection of the reinforcing filament through the sheath fibersFig.15-Reinforced plastics produced by dref method used hybrid yarn34 35. HYBRD YARNS/DREF CORE YARNS For liquid filter cartridges (fig.16) Yarn Properties Huddle fiber arrangement for best filter action High elongation values Long yarn length knotless Uniform yarn with high tensile strength For heat proof woven and knitted fabrics (fig.17) Yarn properties Flame resistance High temperature resistance High tear abrasion resistance Good wearing comfort Good care properties Skin friendly Fig.16-Liquid filter cartridgesFig.17-Fire gloves ,nonflammable woven hybrid fabric produce by friction method.. 35 36. HYBRD YARNS/DREF CORE YARNS For Secondary carpet backings(fig.18)Yarn Properties Steady high tensile strength High uniformity of the yarn Long knotless length of the yarn Good non-rotating properties High chemical resistance Good thermal transfer Dust free product Electric insulation Good dimension stability for carpetsFig.18-Secondary backing fabric of tufted carpet. 36 37. HYBRD YARNS/DREF CORE YARNS For asbestos substitute (fig.19) Yarn properties High yarn volume Good temperature resistance High tensile strength Low elongation Cut proof woven and knitted fabric (fig.20) Yarn properties High cut resistance Good wearing comfort High dimension stability Fig.19-Ropes and Fabrics which are used marine produces by asbestos by frictipn method.Fig.20-Cut roof gloves37 38. ADVANTAGES OF FRICTION SPINNING SYSTEM Greater flexibility of processing a wide range of fibres. Higher production speed (up to 500 mpm). Ability to produce multi component and hollow yarns. Ability to generate huge no of turns per unit length of yarn with one revolution of twisting element. The number of end-breaks in friction spinning is quite low, which results in higher machine efficiency than ring and rotor spinning. Rewinding is eliminated. Bulkier and softer handle than that of ring and rotor spun yarn 38 39. LIMITATIONS OF FRICTION SPINNING SYSTEM Low yarn strength and extremely poor fiber orientation made the friction spun yarns very weak. The extent of disorientation and buckling of fibers are predominant with longer and finer fibers. Friction spun yarns have higher snarling tendency. High air consumption leads to high power consumption. The twist variation from surface to core is quite high; this is another reason for the low yarn strength. It is difficult to hold spinning conditions as constant. The spinning system is limited by drafting and fiber transportation speeds. 39 40. N COMPARSON WTH OTHER SPNNNG SYSTEMS Friction spun yarns are usually weaker than other yarns due its structural weakness. It has been demonstrated that DREF-2 friction spun yarns possess only 60% of the tenacity of ring spun yarns and about 90% of that of rotor spun yarn. It has also shown that friction spun yarn generally has *60 - 70% strength, *60 - 90% unevenness, *100 - 140% bulk and *requires 75 - 100% of the minimum no of fibres in the cross section as compared with the corresponding ring spun yarn. Rotor spun yarns show the highest evenness followed by ring spun and friction spun yarns. The imperfections were also less in friction spun yarns than in rotor spun 40 yarns but higher than those in ring spun yarns. 41. N COMPARSON WTH OTHER SPNNNG SYSTEMS Further friction spun yarns are more hairy than ring or rotor yarns and are more susceptible to stripping back and thus abrading easily. In respect of yarn to metal friction, ring spun yarn exhibits the highest friction, followed by rotor and friction spun yarns for cotton and viscose fibres. With polyester fibre, friction spun yarns show the highest value of friction followed by rotor and ring spun yarns. DREF-3 yarns occupy an intermediate position between ring and rotor spun yarns as far as short hair (up to 3 mm) and total hairiness were concerned. In addition DREF-3 yarns are the most irregular in terms of twist and linear density unevenness, and ring spun yarns are most even. DREF-3 yarns also show a lower resistance to abrasion and repeated extensions than ring and rotor spun yarns. Further the twist level did not have any influence on the rigidity of ring and rotor spun yarns. But the flexural rigidity of DREF-3 yarns decreased41 considerably with increasing twist. 42. REFEFERENCES 1-Wang X, Huang W and Huang XB, 1999, A study on the formation of yarn hairiness, Journal of the Textile Institute, 90 Part 1, No 4, p.555 - 569.2-Grosberg, P. and Iype, C., Yarn production - Theoretical aspects, The Textile Institute, Manchester, 1999. 3-Klein, W., Manual of textile technology Vol 5: New spinning systems, The Textile Institute, Manchester, 1993, p.14. 4-Wulfhorst, B., Evaluation of the new spinning techniques on automation and quality criteria, ITB - Yarn Forming, No. 4, 1990, p. 5 - 13. 5-http://textlnfo.wordpress.com/2011/11/12/dref-spinning/ 6- http://textile2technology.com/2009/10/dref-3-yarn-frictional-behaviour.html 7-Friction Spinning-A Critical View ,N.Balasubramanian,The Bombay Research Textile Association,L.B.S Marg,Ghatkopar (West),Bombay 400 088,13 April 1992. 8-Experimental Study of the Frictional Properties of Friction Spun Yarns, S. S. Ramkumar,* L. Shastri, R. W. Tock, D. C. Shelly, M. L. Smith, S. 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