Blow room is the initial stage in spinning process. The name blow room is given because of the "air flow" And all process is done in blow room because of air flow. Blow room is consisting of different machines to carry out the objectives of blow room. In blow room the tuft size of cotton becomes smaller and smaller. In a word we can say a section in which the supplied compressed bales are opened, cleaned & blending or mixing to form uniform lap of specific length is called Blow room section. During the opening, cleaning, blending or mixing different faults or defects occur in blow room. Now I will discuss about faults/defects, causes and way to remedies in blow room section.
Problems/Faults/Defects in Blow Room:
1. Low cleaning efficiency
2. High nep generation and fibre rupture
3. High variability in the delivered hank
4. Formation of cat's tail
5. Conical lap
6. Lap licking
7. Patchy lap
8. Holes in lap
9. Soft laps
10. Ragged lap selvedge
Causes and Remedies are discussed below:
Low cleaning efficiency:
Lower extraction of wastes than required for that mixing considering the trash content is one of the main reasons for low cleaning efficiency. Increase the wastes if the lint in the wastes is normal or nil. If the beater speeds are lesser than required, we get lower cleaning. Check the beater settings and correct them if needed. Increase the space between the grid bars. Close slightly the air-inlets under the grid bars towards the cotton entry side, and open those on the delivery side. Reduce the fan speed following the beaters by 100 to 200 RPM. If the grip of the feed roller is less, we shall get low cleaning efficiency. Therefore check for the grip. Also check the sharpness of the beaters. Check the synchronization of the machine working. The blending bale openers should work for 80 to 85% of the time of working of the final machine. If there is a back draught because of not cleaning the wastes under the machines, the cleaning efficiency shall come down.