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| No. | Section | Defect | Root causes | Action (remedies) |
|
| 1 | Ring spinning | Thick and thin place | Immature fibers | Use mature fiber |
| High fiber length variation | Properly mix |
| Eccentric top and bottom rollers | Change eccentric top roller |
| Insufficient pressure on top rollers | Apply required pressure on top roller |
| Unevenness yarn | Uneven roving | Control short term autoleveller |
| Bottom roller eccentric | Change eccentric bottom roller |
| Long roving piecing | Give training to operators |
| Broken or damaged roving guide | Change damage roving guide |
| Slubs | Excessive short fibers in the mixing | Properly mix |
| Improper piecing in roving | Give training to operators |
| Bad piecing | Give training to operators |
| Improper cradle holders | Change cardle holders |
| 2 | Roving | Roller lap | Improper ambient conditions in the department | Use required RH% and temperature |
| Damaged surface in the top roller cots | Change top rollers |
| Improper use of spacers | Change spacers |
| Slubs on roving | Excessive end breaks. | Use adequate top roller pressure |
| Waste accumulation at creels | Clean the creel periodically |
| Damage on roller cloth | Change top roller clothing |
| Improper handling in transport | Properly transport the roving |
| 3 | Draw frame | Roller lap in drafting zone | Improper humidity | Use required RH% and temperature |
| Excessive top roller pressure | Use required RH% and temperature |
| Inadequate suction in the pneumatic duct | Use required amount of suction air |
| Excessive trash in the feed material | Use clean raw material |
| High breakage rate | Improper pressure on top rollers | Apply required pressure on top roller |
| Variation in top roller coating | Change top roller or grinding top roller coats |
| Worn top roller end bushes | Change or grinding top roller coats |
| 4 | Carding | High waste generation | High short fiber in the raw material | Properly mix |
| High trash content in the raw material | Use clean raw material |
| Nep formation | High licker in speeds | Adjust licker in speed |
| Uneven flat setting | Adjust flat to cylinder setting |
| Rough surface in front and back plate. | Grind the wire |
| Lunt licker in wire or dull flats | Grind or change licker in wire |
| Card sliver variation | Bent/damaged back and front plate | Change front plate wire |
| Feed roller weighting not acting properly. | Control short and long term autoleveller |
| 5 | Blow room | High waste generation | Use of excessive soft waste in the mixing | Reduce soft waste use in blow room |
| Uneven mixing of soft waste | Properly mix |
| Extreme variation in the ambient condition in the department | Use required RH% and temperature |
| Nep formation in blow room | Cottons with too low moisture | Use required RH% and temperature |
| Extremely fine cottons with high trash content | Completely rejects fine cotton with high trash content |
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