Methods and standards for inspecting appearance defects of precision stamped parts

Precision stamping parts are widely used in the automotive, electronics, and medical industries. Even a small part can significantly impact the overall quality of a product, thus requiring high quality control. Defects in appearance are unacceptable and must be eliminated to avoid affecting the product's aesthetics and usability. So, how are appearance defects in precision stamping parts inspected? Inspection methods and standards for appearance defects in precision stamping parts:

1. Material Defect Inspection Method: Visual inspection. This includes checking for material strength not meeting requirements, marks on the left side of the rolled plate, overlaps, orange peel texture, streaks, loose galvanized surfaces, and peeling of the galvanized layer.

2. Rounded Corner Inspection Method: Visual inspection. This involves checking for uneven, unclear, or uneven rounded corner radii. These defects are not allowed on outer covers, and on the assembly surfaces of some inner covers. Overlapping rounded corners not only affect the appearance of the precision stamping part but also severely impact welding and assembly.

3. Pitting Inspection Method: Visual inspection. The presence of pits severely affects the appearance of the coating, a defect unacceptable to customers. Large areas of pitting can also affect the strength of the precision stamping part, leading to fatigue and irreparable damage.

4. Wrinkle Inspection Method: Visual inspection is required. No wrinkles should be easily detectable by the customer on the outer cover. Severe wrinkles leading to material accumulation are not permitted.

5. Hairline, Indentation, and Scratch Inspection Method: Hairline scratches and indentations are not permitted on the outer surface of the outer cover. Scratches and indentations affecting the outer surface are not permitted on the inner surface of the outer cover. Severe scratches and dents that could cause product breakage are not permitted on the inner cover surface.

6. Burr Inspection Method: Visual inspection is required. Burr length must be less than 10% of the sheet thickness. Any burr affecting fit is unacceptable. Any burr that could cause personal injury is unacceptable. Any stamping burrs affecting part positioning and assembly are unacceptable.

7. Crack Inspection Method: Visual inspection. Any fragmentation on the outer cover is unacceptable. For the inner cover, only minor chip repair welding is permitted, but the repair must not be easily found on-site and must meet the repair standards for precision stamped parts.

8. Necking Inspection Method: Visual inspection, anatomical inspection. Necking is a potentially dangerous fracture point during the forming process of precision stamping parts, significantly impacting their function, strength, and fatigue resistance. The degree of necking determines whether a precision stamping part needs rework or scrapping.

9. Corrosion Inspection Methods: Visual inspection and dissection. Corrosion is caused by prolonged storage or improper storage of stamping parts, leading to rust. It has a crucial impact on the function, strength, and fatigue resistance of the stamping parts.

The above content outlines the methods and standards for inspecting appearance defects in precision stamping parts. It is important to understand these. Precision stamping parts may develop appearance defects during production, requiring inspection and rework by personnel to ensure they meet usage standards and factory requirements.