1. Touch check

Wipe the surface of the outer panel with clean gauze. The inspector needs to wear touch gloves to touch the surface of the stamping parts along the longitudinal direction of the stamping parts. This inspection method depends on the experience of the inspector. If necessary, the suspected area can be polished by oilstone and verified, but this method is an effective and rapid inspection method.

2. Oilstone grinding

2.1. First, clean the surface of the outer panel with clean gauze, and then polish it with oilstone (20 × 20 × 100 mm or larger), and polish the places with arc and hard to reach with relatively small oilstone (such as 8 × 100 mm semicircular oilstone)

2.2. The choice of particle size depends on the surface condition (such as roughness, galvanizing, etc.). Fine grained oilstone is recommended. The direction of oilstone grinding is basically along the longitudinal direction, and fits the surface of stamping parts well. In some special places, horizontal grinding can be supplemented.

3. Polishing of flexible gauze

Wipe the surface of the outer panel with clean gauze. With the flexible sand net close to the stamping surface, along the longitudinal grinding to the whole surface, any pitting, indentation will be easily found.

4. Oiling inspection

Wipe the surface of the outer panel with clean gauze. Then apply oil evenly along the same direction with a clean brush to the whole outer surface of the stamping part. Place the oiled stamping parts under strong light for inspection. It is suggested that the stamping parts should be erected on the body. It is easy to find tiny pits, hollows and corrugations on stamping parts by this method.

5. Visual inspection

Visual inspection is mainly used to find the appearance abnormality and macro defects of stamping parts

6. Inspection of inspection tools

Put the stamping parts into the inspection tool, and test the stamping parts according to the operation requirements of the inspection tool manual.