Yarn Classification
There is no limit of the range of yarns that can be produced by various types of spinning processes. So it is difficult to classify various types of yarns on a single basis. Yarns can be classified on various grounds.
Filament yarn:
· Consists of filament fibres (very long continuous fibres) either twisted together or only grouped together. (Silk man-made fibres)
· A monofilament yarn: consists of only a single continuous filament from a man-made source.
· Multifilament yarn: is a filament yarn made from multiple filaments, assembled with or without twist
Spinning:
· Spinning may be defined as the process of converting fibres and/or filament(s) into a yarn.
· In the production of man-made fibres, the extrusion of the fibre forming liquid through the spinnerets followed by hardening of these liquid gets into solid filaments is called the process of spinning.
· The meaning of the term spinning, in this case, may be completely different from that used for natural fibres.
· Generally, we can define spinning as a process that produces a yarn as its final product. The spinning of man-made fibres can be carried out by three different methods:
(i)Wet Spinning. (ii) Dry Spinning. (iii) Melt Spinning.
- These different types of spinning methods are used based on the properties of the fibre-forming substance.
- For example, in order to spin Viscose Rayon, wet spinning is used and for Nylon we use the melt spinning.
- Some fibre-forming substances can be spun by using more than one type of the above-mentioned spinning techniques.
Carded Yarns-
Short Staple, less regular in size and appearance, medium to low twist, more protruding ends, bulkier, softer, fuzzier, more sensitive to abrasion, more fibres present, may become baggy in areas of stress, fabrics vary from soft to firm.
Combed Yarn-
Long staple, regular in size and appearance, medium to high twist, fewer protruding ends, finer count, longer wearing/ stronger, fewer fibres present, smoother surface, lighter weight, do not sag, take and hold a press.
Folded Yarns-
Folded or plied yarns are spun from two or more single yarns by twisting them together. To fold or two-ply yarn, for example, is composed of two single yarns and three-ply or threefold yarn is composed of three single yarns. Depending upon twist direction two methods are used to make a plied yarn:
I. All the individual single yarns are twisted in one direction and are then combined and twisted in the opposite direction to form a uniform and soft folded or plied yarn.
II. All the individual single yarns are twisted in one direction and are again combined and twisted in the same direction to form a hard and less flexible folded or plied yarn.
Uses of Folded Yarns-
I. Folded yarns are used for heavy industrial fabrics where extra strength is needed.
II. By the process of folding, a very coarse yarn that is impossible to make on ordinary spinning machines can be made.
III. Folded yarns made from very fine fibres are used in delicate looking sheer fabrics.
Cabled Yarns-
Cabled or Corded yarns are produced by twisting two or more plied or folded yarns together. Cabled or Corded yarns can be produced by different combinations of twist directions:
I. Usually cabled yarns are made with the final twist usually applied in the opposite direction of the ply twist.
II. Cables or cords may follow an SZS form, with S-twisted singles made into Z-twisted plies that are then combined with an S-twist, or may follow a ZSZ form.
III. The cabled or corded yarn may also follow an SSZ or a ZZS pattern.
Uses of Cabled or Corded Yarns-
I. Corded yarns may be used as rope or twine.
II. They may also be made into very heavy industrial fabrics
III. Cables made from extremely fine fibres are used to make sheer dress fabrics.
Bulky Yarn:
Bulky yarn is a yarn that has been processed to have covered power or apparent volume than that of a conventional yarn of equal linear density and of the same basic material with a normal twist (ASTM standard) often these bulk yarns are referred to as bulk continuous filament yarns. (BCF)
Bulky Yarns:
Bulky Yarn formed from inherently bulky fibres such as manufacturing fibres that are hollow along part or all of their length, or yarns from fibres that cannot be closely packed because of their cross-sectional shape, fibre alignment, stiffness, resilience or natural crimp (ASTM Standard). Bulky yarns are used in a wide array of products from carpeting to lingerie and sweaters to shoelaces.
Stretch yarns:
Stretch yarns are a thermoplastic filament or spun yarns with a high degree of potential elastic stretch (300-500%), rapid recovery and a high degree of yarn curl (ASTM Standard). Stretch yarn has moderate bulk. Stretch yarns (nylon) used extensively in men’s and women’s hosiery, pantyhose, leotards, swimwear, jerseys. Stretch yarns are not the same as elastomeric fibres.
Textured yarns:
Textured is a general term for any continuous filament yarn whose smooth, straight fibres have been displaced from their closely packed, parallel position by the introduction of some form of a crimp, curl, loop or coil.
Fancy yarns:
The fancy yarns are also called as Novelty Yarns. Fancy yarns may be single, plied, or cord yarns. They may be spun, filament, or textured yarns or any combination of yarn types.
Blended Yarn:
A blend is an intimate mixture of fibers of different composition, length, diameter or color spun together into one yarn. Mixture refers to yarn of different generic types within a fabric. In a mixture, yarns of one fiber type are used in the warp and yarn of another type used in the filling.
· Yarns are selected for different textiles based on the characteristics of the yarn fibers, e.g. Warmth (wool), lightweight (cotton or bamboo), durability (nylon), softness (cashmere, alpaca).
· The most widely used blends:
1. Cotton-polyester (comfort and absorbency of cotton with the strength and wrinkle resistance of polyester.)
2. Wool-acrylic fiber
Blends of different natural fibers are common too, especially with more expensive fibers such as alpaca, angora and cashmere.
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