Abstract: When the stem cutter SQ3X cut high pressure steam processed stems,sticky matter tends to adhere to the grinding wheel and results in blunt knives and unqualified cut stem thickness. Therefore, a device for cleaning the grinding wheel was designed. The said device adopted vortex tube as a heater,the hot air came out of the vortex tube dried the sticky matter and forced it to flake off the grinding wheel,proper grinder dressing was ensured. A function block of temperature control program was established in the PLC of the stem cutter to control and adjust the temperature at grinding area automatically and real-timely. The results showed that after improvement,the amount of stems adhered to the grinding wheel reduced effectively,the knife blades were well sharpened. When the temperature at grinding area was set at 80℃,the electric current of knife drum motor decreased from 76.2 A to 43.2 A,the qualified rate of cut stem thickness increased from 70% to 90%. The performance of stem cutter is promoted effectively.