Twisted yarn is referred to by several specific names depending on the direction of the twist, the number of individual strands, and how they are combined. Broadly, twisted yarns can be categorized as single yarns, S-twist yarns, Z-twist yarns, or plied yarns.
Understanding Twisted Yarn Types
Yarn twisting is a fundamental process that imparts strength, durability, and texture to textile fibers. The direction and amount of twist significantly influence the final properties and applications of the yarn.
Single Yarns
Single yarns are the most basic form of twisted yarn. These are created when fibers are twisted together in a single direction. This initial twist holds the fibers together, forming a continuous strand suitable for various uses.
Twist Direction: S-Twist and Z-Twist
The direction of the twist in a yarn is crucial for its characteristics and how it behaves when combined with other yarns or during fabric formation.
- S-Twist Yarn: This type of yarn is characterized by a twist that goes to the right. When held vertically, the spirals in an S-twist yarn appear to follow the direction of the central part of the letter "S."
- Z-Twist Yarn: Conversely, Z-twist yarn has a twist that goes to the left. If held vertically, the spirals in a Z-twist yarn resemble the central part of the letter "Z."
The choice between S-twist and Z-twist yarns often depends on the desired fabric structure, feel, and the subsequent processes the yarn will undergo.
Plied Yarns
Plied yarns, also known as balanced yarns, are created by twisting two or more single yarns together. This additional twisting process enhances the yarn's strength, uniformity, and resistance to abrasion. By combining multiple single yarns, plied yarns achieve greater bulk and can reduce yarn bias, leading to more stable fabrics.
The specific type of twisted yarn — whether single or plied, S-twist or Z-twist — is chosen strategically based on its intended purpose and the performance requirements of the final textile product. Different applications require different yarn properties, making the various twisting methods essential in textile manufacturing.
Summary of Twisted Yarn Nomenclature
| Type of Twisted Yarn | Description |
|---|---|
| Single Yarn | Yarns that have been twisted in one direction. |
| S-Twist Yarn | Yarns twisted specifically to the right. |
| Z-Twist Yarn | Yarns twisted specifically to the left. |
| Plied Yarn | Formed by twisting several single yarns together; also known as balanced yarns. |
