Yarn spinning is the process of manufacturing yarn from different types of fibres into a continuous length from one or more type of fibres, writes Pradeep Kulshrestha.
Spinning is the most important and the initial step in fabric manufacturing. The major task of spinning is to produce a variety yarn from raw material, then remove the process faults followed by winding the short length bobbins on cones. There are different types of spinning; the most common forms are: ring, rotor, air jet, friction, etc.
Construction of textile yarns
Yarn count, yarn ply and yarn construction interrelate to form the characteristics of yarn. Yarn construction is classified as:
Conventional yarn: These are two or more simple single yarns plied or twisted together. They are referred to as two, three, four, five or six ply yarn. Size and number of plies may be changed for different weaves or fabric structures.
Complex/novelty yarns: These are single or plied yarn structures characterised by internationally introduced irregularities in size and twist effects. The irregularities of novelty yarns may be uniform or random.
Metallic yarns: A monofilament flat yarn produced by lacquering aluminium pigment or by laminating aluminium foil between layers of plastic. After this webs are cut into wide coils and the rolls are slit into fine ribbon-like yarn. After slitting, the yarn is wound onto spools or coils depending on type of ribbon. Since metallic yarns are flat rather than round most as most of other man-made fibre yarns, the size of the yarn is specified in inches.
Textured yarns: Textured yarns are the end result of physical, chemical or thermal manipulation of fibres and yarns so that they are no longer straight or uniform. The manipulation process of textured yarn results in the modification and altering of the arrangement of the fibres and yarn. Texturising produces a permanent change in the physical structure of the yarn. The fibres no longer lie parallel to the other.
Bulked/high bulked/lofted yarns: High bulk yarns are created and processed by nonlinearity or loop formation in individual filaments. The process introduces crimps, loops, curls and crinkles into the yarn. Bulk yarn may also be shrunk and stretched introducing shrink differentials. The resulting yarns of these processes are bulked, fluffed, puffed and twisted yarns.
Stretch yarns: Almost all man-made and natural fibres can be treated to produce yarns with some degree of stretch and recovery. Stretch properties may be applied to yarns by chemical or mechanical methods. Not all methods or fibres will achieve equally effective stretch properties.