Inspection method: visual inspection, whetstone polishing, touch, oiling
Class A defects: Users who have not been trained in stamping parts Ⅰ and Ⅱ can also notice this type of wave, but the user cannot accept them, and the stamping parts must be frozen immediately after discovery.
Type B defects: This type of wave is an unpleasant defect. The tangible and visible waves in the stamping parts I and II need to be repaired.
Type C defects: defects that need to be corrected. Most of these waves are ambiguous and can only be seen after the oilstone is polished. Such wave stamping parts are acceptable.