Polyester staple fiber, also known as PET fiber, is made of polyester monomer through polymerization, stretching, curling and other processes. Polyester fiber has many excellent characteristics, such as high strength, wear resistance, wrinkle resistance, easy drying and so on. The strength of polyester yarn produced by this polyester fiber is higher than that of natural fibers such as cotton yarn and hemp yarn, and it can bear greater tension and wear, and it is not easy to deform and shrink, so it is widely used in textilipar.