Explain the importance of blending different varieties of cotton (or) why mixing is done in Blow Room (or) what are the reasons for mixing different cotton in spinning mill. What are the objects of mixing (or) Briefly explain the necessity of mixing (or) What are the advantages of mixing of fibres in Blow Room Mixing is the process of intermingling of various varieties of cotton, to prepare the raw material for the spinning process.
It is not possible or economical to depend upon a single variety of cotton to produce a particular yarn throughout the year. So. different available varieties are selected and mixed in a suitable proportion so as to get uniform Quality product throughout the year. Object of mixing process are
To improve Processing Performance of Spinning:
| Department | Defects | Remedial precautionary steps to be taken in mixing |
| Carding | The level and | Can be controlled by maintaining |
|
| variation of | the mixing compositions as |
|
| neps and waste | Constant as possible. |
| comber |
Fluctuation in noil% | Can be reduced by eliminating High short fibre content In mixing to control variation, in fibre length distribution of blend.
|
| Fly frame | fly
| |
| Fly frame |
Twist variation in roving
| Can be controlled by mixing cotton on the basis of closer fiber length and micronaire fibre length and micronaire reading tolerances cotton on the basis of closer fibre length and micronaire
|
By closely controlling fibre length and micronaire reading of blends, twist variation in yarn is: kept minimum, resulting in better control over yarn strength and end breakage levels.
Uniformity of sliver and roving is dependent mainly^ on fibre properties and machinery adjustments.
Mixing influence the processing performance of spinning through control of yarn count variation, twist variation, end breaks, yarn properties, machinery adjustments.
To achieve uniform quality of Products:
There is wide variation in fibre properties from cotton to cotton. Even the same variety of cotton indicates' variation from fibre to fibre. So, to achieve uniform quality of product, different varieties of cottons are mixed in a suitable proportion in order to (average out the inherent variation exist in each variety of cotton.
To reduce and control the cost of production:
Mixing Influence the price of final product through control of fibre cost, fibre quality, Blend composition.
Availability, inventorying, ware housing, purchasing program & inherent fibre property variations.
To meet functional end use requirement:
Blending influences (I) physical properties such as tensile
& tear strength, elasticity, abrasion resistance (durabi1ity), wrinkle resistance, etc., (ii) Aesthetic properties such as
appearance, cover, surface, colour, luster, drape etc., and (iii) subjective properties such as comfort, hand and touch, softness, loftiness, fullness etc.,
1. Where ultimate strength is required,
cottons of high fibre strength are used to get strong yarn and fabric.
2. where aesthetic properties are required, cottons of low-nep potentials are used in blend.
3. where subjective properties (comfort, softness, fullness, etc., are required:
long and fine fibres are used in blend in combination with spl. fabric finishing treatments.
To regain the moisture content.
cotton is a hygroscopic material. The compressed bale of cotton losses some moisture during compression. So, cotton must be opened and stored sufficiently to regain its moisture content.
