Fault analysis using symmetrical componentsFull description
Faltas apc200
"Spark on YARN"Full description
Spinning Intoduction What is Textile Spinning? Yarn Manufacturing Introduction
1/24 By: Abu Bakkar Marwat NTU Faisalabad 0313-6660505 [email protected] Textile Testing-II (TS-333) 2/24 Table of contents: Introduction Types of irregularity Causes of irregularity Denotin...
Yarn quality parameters are discussed....
CASE fault codeDescripción completa
folds faults and joints
BGAS
Faltas apc200Full description
Laporan Akhir Praktek Drawn Texture Yarn (DTY).
faults and alarms
Yarn fau fault ltss Types Causes remedies
Staple
yarn defects
arise from raw materials, machinery settings, improper maintenance RAW MATERIAL: For cotton : immature fibres neps trash, etc For wool : grease suint veg matters, etc
Filament
yarns
Defects arise from differences in the morphology of the polymer rather than from differences in linear density For man made fibers concentrations of finish oligomers undrawn or improperly drawn segments of fiber
slub(long thick place) Abnormally thick place of length 1-4 cm and about 5-8 times larger than average yarn dia showing less twist at that place of the yarn Eff ects
More end breaks in the ensuring process Damaged fabric appearance Shade variation in dyed fabrics
Causes
Poor individualization of fibers at the card Lack of adequate fibre control in the drafting region Accumulation of fly and fluff on machine parts Improperly clothed top roller clearers Defective RF drafting and bad piecing Too close roller setting
Remedies
Better opening and cleaning in BR and carding Replace defective aprons Optimum top roller pressure and back zone setting at RF to be maintained Excessive roving twist Broken teeth in gear wheel to be avoided and proper meshing to be
oily slub Slub in the yarn stained with oil Eff ects
More end breaks in the subsequent processes Damaged fabric appearance Shade variation in dyed fabrics
Causes
Remedies
Accumulation of oily Yarn contact surfaces to fluff on machine parts be kept clean Improper lubrication Proper lubrication and Negligence in segregation segregating the oily waste from process waste
Kitty yarn( bakar ) Presence of black specs of broken seeds, leaf bits and trash in yarn. Eff ect
Damaged fabric appearance Production of specks during dyeing Needle breaks during knitting Poor performance during winding
cause
Improper ginning i.e. Seeds broken during ginning Ineffective cleaning in blow room and cards Use of cotton with high trash and too many seed coat fragments
remedy
Good ginning practices Cleaning efficiency of BR and cards should be improved. Optimum humidity in the departments should be ensured
Foreign
matters
Metallic parts, jute flannel and other similar foreign matter spun along with yarn Eff ects
Breaks during winding Formation of holes and stains in the cloth Damaged fabric appearance
Causes
Improper handling of travellers Improper preparation of mixing
Remedies
Removal of foreign matters should be ensured during preparation of mixing Installation of permanent magnets at proper places in BR lines
Cork
screw yarn
Double yarn in which one yarn is straight and the other is coiled over it. Eff ects
Breaks during winding causes streaks in the fabric
Causes
Feeding of two ends in the RF Lashing in of ends in RF
Remedies
Tenters are to be trained in piecing practice Pneumafill ducts to be kept clean and properly set
Snarl/over
twisted yarn
Yarn with kinks(twisted onto itself) due to insufficient tension after twisting Eff ects
Entanglement with adjacent ends causing a break Damaged fabric appearance Shade variation in dyed fabrics
Causes
Wrong selection of twist wheel Wrong selection of spindle driving pulley Presence of too many long thin places in the yarn
Remedies
Optimum twist to be used for the type of cotton processed Drafting parameters to minimize thin places in yarn to be adopted Yarn should be conditioned Correct tension weights and slub catcher settings should be employed at winding
Soft
yarn
Yarn which is weak indicating lesser twist Eff ects
More end breaks in subsequent processes Shade variation in dyed fabrics
Causes
Cord slippage on spindle wharves Improper bobbin feed on the spindles Less twist in the yarn Bad clearing at the traveller
Remedies
Vibration of bobbin on the spindle should be avoided Proper yarn clearing should be ensured Periodic replacement of worn rings and travellers
Oil
stained yarn(daghi)
Oil or stain marks present on the yarn Eff ects
Damaged fabric appearance Occurrence of black spots in the fabric
Causes
Over flowing of oil from spindle bolster Excessive oil on ring with intention of running the traveller smoothly Improper material storage and handling Piecing made with oily or dirty fingers
Remedies
Proper oiling and greasing Proper material storage and handling
Spun in
fly
Fly or fluff either spun along with the yarn or loosely embedded on the yarn Eff ects
Causes
More breaks in winding
Accumulation of fluff over m/c parts(captured b/w front drafting rolls and pigtail guide) Fanning by workers Failure of over head cleaners Malfunctioning if humidification plant
Remedies
Machinery surfaces to be kept clean by use of roller pickers Fanning by workers avoided Performance of overhead cleaners and humidification plants should be closely monitored
Bad
piecing(moree)
Unduly thick piecing in the yarn caused by over end piecing
Eff ects
More end breakages in subsequent processes Increase in hard waste
Causes
Wrong method of piecing and over end piecing Twisting the ends instead of knotting Too close roller setting
Remedies
Proper piecing Separators should be provided Excessive end breakages in spg should be avoided
crackers Very small snarl like places in yarn which disappear when pulled with enough tension or yarn with spring like shape Eff ects
More breaks in winding More noticeable in P/C blended yarns
Causes
Mixing of cotton of widely differing staple lengths Closer roller settings Eccentric top and bottom rollers Over spinning of cottons Non optimum temp and RH in the spg shed Long fibers(bridge the nip line in drafting system and disrupt the process)
Remedies
Optimum top roller pressure Optimum roller setting Use of properly buffed rollers free from eccentricity to be ensured Mixing of cottons varying widely in fine length to be avoided
THICK AND THIN Eff ects
More end breaks in winding Damaged fabric appearance Poor knitting performance
PLACES
Causes
Eccentric top and bottom rollers Insufficient pressure on top rollers Worn and old aprons and a improper spacing Improper meshing of gear wheels Mixing of varying length cotton and use of immature cotton
Remedies
Eccentric top and bottom rollers to be avoided Top arm pressure checking schedules to maintained strictly Correct spacers to be utilized
NEPS Very short fault of more than 200% of the yarn dia Eff ects
Damaged fabric appearance End breaks in subsequent process
Causes
ginning Improper opening in BR Poor carding due to improper settings Use of low micronaire cottons
Remedies
Correct settings and speeds in BR and cards to be maintained Grinding schedules to be maintained strictly Avoid immature cotton Use of long cotton
Neps level
Raw material (bale) : 100 -900 neps/g BR : slightly less than bale Card : 25 -300 neps /g Combing : 7-80 neps /g
Measurement : vary with count ring spg ± 200% yarn dia rotor spg ± 300% yarn dia
BALL
Eff ects
end breakage in subsequent process
Causes
Accumulation of lint (short fibres debris from drafting)on the traveler
Remedies
Use of over head cleaners
FISHES
Eff ects
affect fabric appearance
Causes
Drafting under too dry conditions can cause static electricity to be generated by the sliding fibres
Remedies
optimum RH should be maintained
HAIRINESS Protrusion of fibre ends from the main yarn structure Eff ects
More end breaks in winding Uneven fabric surface Beads formation in the fabric in the case of P/C blends
Causes
Use of cottons differing widely in the properties in the same mixing Worn rings and lighter traveler Low RH Close roller settings Very high spindle speeds
Remedies
Traveler of correct size and shape Use of rings in good conditions Periodic replacement of traveler Correct roller settings Maintaining Optimum RH Wide cotton mixing should be avoided
