What are the inspection standards for automotive metal stamping parts?

2023-10-17 08:38:03

Parts drawings/inspection guidance (standard) book: Some simple hardware automotive stamping parts can be inspected by comparing the various dimensions marked in the drawings, followed by the use of various measuring instruments, basic tape measures, calipers, micrometers, tables, Stop rules and so on. Also pay attention to some important tolerances marked on the drawings and whether the tolerance range is consistent with the drawings. For some high-precision products, tolerance requirements must be strict.

Special inspection tool: This is relatively simple. It depends on the actual condition of the parts and needs to be used skillfully.

Sample parts: For some parts that do not have inspection tools, but whose shape is relatively complex and cannot be expressed in two-dimensional drawings. You can use the quadratic circle test. The signature plate is an intuitive reference object, which can be used to see whether the structure is OK, the surface treatment, and the front edges.

The defective materials have already been mentioned. You can check online for details. The above are the inspection standards. After knowing these, it is basically enough for a beginner inspection. Other aspects cannot be expressed on the drawings. It requires your familiarity and experience with the stamping process. For example, just get one. For auto parts, a master craftsman can immediately know where to focus, where problems are likely to occur, what are the possible causes of the problem, what impact it will have on subsequent processes and the entire part, what impact it will have on the mold, and how to adjust it. What should production line personnel pay attention to, what will be done in subsequent packaging, and even what impact it will have on the overall product. For example, for some cosmetic items, corrosion on the surface of the product is absolutely not allowed. The corrosion not only affects the appearance, but also poses a threat to human safety, etc.

These cannot be explained clearly in one or two sentences and require the accumulation of a lot of experience. Defects of metal stamping parts: poor materials, pits, pits, scratches, bruises, necking, cracking, rolling, roughening, uneven drawn side walls, wrinkles, large burrs, missing edges, hole deformation, Missing holes, hole deviation, flanging warping, flanging/bending not in place, trimming line/flanging/bending line offset, flanging height discrepancy, forming (drawing)/shaping not in place, poor stiffness, etc. There may also be many problems with the surface treatment of stamped parts: such as poor plating (skin peeling, color difference, etc.); poor sandblasting (uneven sand points, too thick or too fine sand points); poor oxidation (color difference, watermark points); and Other issues such as silk screen, high gloss, polishing. These will affect the appearance of the product.