Defects in Blow room and causes.

Causes for Nep formation in Blow room;

*Cotton with too high or low moisture.

*Extremely fine cottons with high trash content.

*Reprocessing of laps and mixing of soft waste.

*Rough or blunt blades and bent pins on beaters.

*Narrow settings between the feed roller or pedal and beater.

*Long curved and U-bends in conveyor pipe lines.

inappropriate ratio of fan to beater speed.

*Wider setting between stripping rail and beater blade.

3. Causes for curly cotton:

*Grid bars setting too close to beater.
*Hooked or bent pins on kirschner beater.

*Too wide a setting of stripping rail.

*Long and bent conveyor ducts with low fan speed.

4. Causes for lap licking :

*Use of too much soft waste in mixing

*Too high fan speed, excessive beating.

*Weigher cotton is damp or departmental humidity is high.

* Sticky nature of material

Remedies: use of roving ends within the lap to act as a layer Separation.

Incorporation of lap felter's.

Use of antistatic spray while processing synthetic.

5. Causes for conical lap:

*Improper functioning of pedals on one side due to pedals being choked with dirt.

*Air entering at one side frcm under the grid bar of beater.

*Defective beater blade at one side.

*Uneven suction at the cages leaving to deposition of more material on one side than another.

*Lap roller racks, calander roller not exerting even pressure across the lap width. *Cages may not be properly levelled.

6. Causes for Soft lap

*Calender pressure inadequate due to wear and tear of weighting mechanism.