process is used today across the word to produce fine and extra fine quality yarns from special fibers such as wool,cashmere,mohair,angora, merino and so on...The Chengsheng automatic "FN7 Double Drive" model is available with a high degree of automation and a centralized computer that controls all the machine functions, including the carriages movement, the feed carriage speed, the adjustment of yarn feed and drafting percentag- es,the reverse speed,the spooling speed, the cops formation, the alarms operating data recording and the production setting data modification history.