Abstract: The brush type plasticizer system in KDF₂ filter rod maker tends to result in wide variation in triacetin addition and material waste.In order to improve the quality of filter rod,an automatic triacetin spraying system based on atomizing technology was designed,wherein PLC and touch screen acted as main controllers.Heated triacetin was pumped into a manifold under high-pressure then evenly sprayed on the running tow by nozzle.By means of the build-in positioning function of PLC and servo positioning module,the tow speed was tracked,the plasticizer valve was accurately controlled to adjust the flow rate of triacetin.By detecting the triacetin temperature and level in the plasticizer booth,triacetin temperature and volume were automatically maintained.The practical testing results showed that the filter rod hardness reached 88%±1.8%,and the process capability index for rod hardness was above 1.4.Triacetin was sprayed evenly and the system ran smoothly and reliably.The average amount of rod break-out and rejection reduced from 38 g to 5.8 g and from 1282 g to 32 g,respectively.