What are the uses of polyester yarns? Polyester yarns are generally divided into the following three categories of uses in production and processing: 1. Weaving yarn: Weaving yarn refers to the yarn used for processing woven fabrics, which is divided into two types: warp yarn and weft yarn. The warp yarn is used as the longitudinal yarn of the fabric, which has the characteristics of large twist, high strength and good wear resistance; the weft yarn is used as the transverse yarn of the fabric, which has the characteristics of small twist, low strength, but softness. 2. Knitting yarn: Knitting yarn is the yarn used in knitted fabrics. The yarn quality requirements are high, the twist is small, and the strength is moderate. 3. Other yarns: including sewing threads, embroidery threads, knitting threads, miscellaneous threads, etc. According to different uses, the requirements for polyester yarn are different.