Industrial fiber spinning equipment

Another difference found in these lines is the size of the packs. The spinneret capillaries are larger. The quench units are also much longer, and often include delayed quenching. The spinning speed is traditionally lower, with a range from 1000 to 2000 m per min. These three differences are required to allow the fibers to cool and be extended over the longer residence time 

The fibers are interlaced and generally wound on packages at speeds from 2500 to 3500 m per min. Because of the high tex of these yarns, doffing or removal of the packages from the winder occurs frequently. Little has changed in this process or the equipment used during the past few years (Nakajima, 2000). 

---

Could a similar phenomenon occur in the melt Were thermotropic polymers possible They were possible, and indeed the number reported to date by academic and industrial researchers is nearly beyond count. In addition, as it later turned out, aromatic thermotropic polymers were found to offer a great many more useful properties than just their now well-known tensile capabilities. These polymers are injection moldable, albeit at temperatures in the vicinity of 400° C, a temperature not compatible with common melt-spinning equipment. The rate of thermal degradation of such a polyester at 400° C makes stable fiber production particularly difficult. Moreover, most conventional injection-molding equipment requires modification to operate at the high temperatures needed to ensure reasonable processing of this polymer. 

For continuity in a yam the fibers must be twisted. This is the process we call spinning - producing yarn fi-om fibers, for example on a spinning wheel - but industrial equipment has been developed for spinning on a larger scale. More than 50% of the world s yarn production is based on fibers. Cotton is still fiber material number one, being used in pure cotton yams but also in blends with synthetic fibers. 

---