Plastic machinery, ceramics machinery,electrical machinery,light industrial machinery, pharmaceutical machinery,packaging and printing machinery,paper-making production line,chemical fiber production lines,escalators,wire and cable machinery,printing machinery,processing machinery ,machine tools, textile printing and dyeing and equipment bag,cold rolling,low-frequency roll,centrifuges,a direct substitule for the exchange of the exchange of torque motor for the general constant tension open-book collection or volume control.