Yarn Spinning, Blow Room Functions
Blow room is the starting of the spinning operation where the fiber is opened, cleaned, mixed, micro dust removed and evened thus passed to carding machine without increasing fiber rupture, fiber neps, broken seed particles and without removing more good fibers. The basic functions of blow room are opening, cleaning, dust removal, blending and evenly feeding the material on the card.
Functions of Blow Room
- The opening is the first operation within the blow room in which the goal is always a high degree of openness of material with gentle treatment and a fiber loss as less as possible.
- The opening is the first operation it means, tearing apart the compressed and matted cotton until it is very much loosened and separated into small tufts with a gentle treatment, and a fiber loss as small as possible.
- The opening is also related to cleaning as where is opening there is also cleaning.
- Cotton contains up to 18% trash in most cases. To clean the material it is unavoidable to remove as much fiber as much waste.
- Therefore it is necessary to measure the amount of the waste removed and its composition. As it is of high importance also called cleaning efficiency.
- The cleaning efficiency always has to be optimized and not maximized, since the fiber quality (short fibers, neps), as well as fiber loss, is always negatively affected by maximum trash removal.
- Dust removal
To extract the contamination in the cotton such as leaf, stone, iron particles, jute, poly
propylene, colored fibers, feather and other foreign material from cotton by opening and
- An often underestimated task of the blow room line is the removal of dust. However, it is as important as the removal of impurities.
- Dedusting in the blow room happens by air suctioning only, either between the machines, e.g. by dust cages, dust extractors, etc. or within the machine by normal air separation.
- Every blow room machine must be capable of extracting dust, so that special dedusting machines should be needed.
- The efficiency depends not only on the devices but also on the size of the flocks. The smaller the flocks, the higher is the efficiency.
Mixing: It is generally meant as the intermingling of different classes of fibers of the same grade e.g. USA Pima grade2, CIS
Blending: IT is meant as the intermingling of different kinds of fibers or different grade of same fibers e.g. polyester & cotton, Viscose & cotton.
- The blending of fiber material is an essential preliminary in the production of a yarn.
- Fibers can be blended at various stages of the process. These possibilities should always be fully exploited, for example, by transverse doubling.
- However, the starting process is one of the most important stages for blending, since the components are still separate and therefore can be metered exactly and without dependence upon random effects.
- A well-assembled bale layout and even (and as far as possible, simultaneous) extraction of fibers from all bales is therefore of paramount importance.
Objectives of mixing or blending
- Processing performance
- Functional properties
- Even feed of material to card
To uniform feeding to the next stage such as carding machine.
- Recycling the waste material
Blow room is the starting of the spinning operation where the fiber is opened, cleaned, mixed and evened.
The whole machine is subject to suction and the dust is collected in special filters; the material, on the other hand, undergoing contemporaneously, the rotary action of the cylinder and suction along the operating width, effects a helical movement around the drum and exits from the side opposite to that on which it entered. It is then transferred by the delivery hopper into the transportation conduit.