(1) thread cutter accelerated wear or excessive wear ① Cause: cutting speed and feed rate choice is incorrect. Solution: Make sure to select the correct cutting speed machining parameters from the table and feed. ② causes: too much pressure on the tool. Solution: Reduce the amount of feed per tooth; shorten tool change time interval; excessive wear checks CNC tool - at the start of the thread will wear fastest. ③ causes: incorrect choice of coating, resulting in BUE. Solution: To study the applicability of other coatings; increased coolant flow rate and flow. ④ Reason: Spindle speed is too high. Solution: Reduce the spindle speed. (2) cutting edge chipping ① Cause: cutting speed and feed rate choice is incorrect. Solution: Make sure to select the correct cutting speed machining parameters from the table and feed. ② Reason: thread mills from moving or slipping on their holding device. Solution: use hydraulic chuck. ③ causes: lack of machine tool rigidity. Solution: Make sure the workpiece clamping reliable;, if necessary, re-clamp the workpiece clamping or improve stability. ④ causes: insufficient coolant pressure or flow. Solution: Increase the coolant flow rate and flow. Appears on the stairs (3) thread type ① Cause: Feed rate is too high. Solution: Reduce the amount of feed per tooth. ② Reason: ramping processing program using axial movement. Solution: Make sure the thread cutter on the large diameter of the thread milling teeth-shaped curve, and not to move radially. ③ Cause: Thread milling excessive wear. Solution: Shorten the tool change time interval. ④ Cause: tooling parts and clamping parts too far away. Solution: the shortest possible tool overhang on the clamping device. (4) test results there is a difference between the workpiece and the workpiece ① Cause: tooling parts and clamping parts too far away. Solution: the shortest possible tool overhang on the clamping device. ② causes: incorrect choice of coating, resulting in BUE. Solution: To study the applicability of other coatings; increased coolant flow rate and flow. ③ Cause: Thread milling excessive wear. Solution: Shorten the tool change time interval. ④ causes: the work shift on the fixture. Solution: Make sure the workpiece clamping reliable;, if necessary, re-clamp the workpiece clamping or improve stability.